Aerosols - Scholars

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Gonzaga Debate Institute 2008 Scholars

1 Aerosols

Aerosols Aerosols..........................................................................................................................................................................1 ***SO2/DIMMING DA.................................................................................................................................................3 1NC SO2/Dimming DA [1/2].........................................................................................................................................4 1NC SO2/Dimming DA [2/2].........................................................................................................................................5 Dimming-Uniqueness-Block Extension/A2: CAA.........................................................................................................6 Dimming-Uniqueness-Fossil Fuel Use High Now [1/2]................................................................................................7 Dimming-Fossil fuels=Aerosols.....................................................................................................................................8 Dimming-Aerosols k2 Dimming....................................................................................................................................9 Dimming-Warming pollutants = Dimming...................................................................................................................10 Dimming ⇓ solvency.....................................................................................................................................................11 Dimming Good-Solves Warming [1/3].........................................................................................................................12 Dimming Good-Solves Warming [2/3].........................................................................................................................13 Dimming Good-Solves Warming [3/3].........................................................................................................................14 Dimming = Negative Feedback....................................................................................................................................15 Dimming-Reducing aerosols=More warming..............................................................................................................16 Aerosols Solve Warming – IPCC Concurs...................................................................................................................17 Dimming Good-Solves Warming-Solves Rice [1/2]....................................................................................................18 Dimming Good-Solves Warming-Solves Rice [2/2]....................................................................................................19 Dimming Good-Solves Drought-Solves Rice...............................................................................................................20 Dimming Good-Solves Warming-Solves Corn [1/2]....................................................................................................21 Dimming Good-Solves Warming-Solves Corn [2/2]....................................................................................................22 Dimming Good - Soil Moisture....................................................................................................................................23 Soil Moisture Impact - Drought....................................................................................................................................24 Soil Moisture Impact - Biodiversity.............................................................................................................................25 Dimming Good-solves Forest Growth..........................................................................................................................26 Dimming Good- ⇓ Sea Temps......................................................................................................................................27 Dimming Good-Solves Fish-Cold Waters Good..........................................................................................................28 Dimming Good-Solves Coral Bleaching......................................................................................................................29 Dimming Good-Dimming Solves Plankton [1/2].........................................................................................................30 Dimming Good-Dimming Solves Plankton [2/2].........................................................................................................31 Dimming Good-Solves Sea Levels...............................................................................................................................32 Dimming Good-Solves Wheat/Grain-Colder Temps....................................................................................................33 Dimming Good-Solves Wheat-Warming Kills Wheat..................................................................................................34 Dimming Good-Solving warming=More Warming [1/3].............................................................................................35 Dimming Good-Solving warming=More Warming [2/3].............................................................................................36 Dimming Good-Solving warming=More Warming [3/3].............................................................................................37 Dimming Good-Solves Disease....................................................................................................................................38 Warming=Dimming in South & East U.S. [1/2]...........................................................................................................39 Warming=Dry Heat in Western U.S..............................................................................................................................40 Warming=Dimming in South & East Asia....................................................................................................................41 Fast Warming Worse.....................................................................................................................................................42 *** WETLANDS METHANE.....................................................................................................................................43 Methane Wetlands Turn................................................................................................................................................44 Methane Wetlands Turn................................................................................................................................................45 Methane Wetlands - Unique Link.................................................................................................................................46 Methane Wetlands Turn – Must Read...........................................................................................................................47 Methane Wetlands Turn – Must Read...........................................................................................................................48 Wetlands Methane - Aerosols Decrease Methane.........................................................................................................49 Wetlands Methane - Aerosols Decrease Methane.........................................................................................................50 Wetlands Methane - Research Proves...........................................................................................................................51 Wetlands Methane - Time Frame / Studies..................................................................................................................52 Wetlands Methane - Time Frame.................................................................................................................................53 Wetlands Methane - Impact + Neg Studies Indite.......................................................................................................54 Wetlands Methane - Positive Feedback.......................................................................................................................55 Wetlands Methane - AT: We Overestimate..................................................................................................................56

Gonzaga Debate Institute 2008 Scholars

2 Aerosols

Wetlands Methane - AT: Volcanoes..............................................................................................................................57 ***ANSWERS TO ANSWERS...................................................................................................................................58 Dimming-AT: “Most Aerosols are natural”..................................................................................................................59 Dimming-AT: Previous studies.....................................................................................................................................60 Dimming-AT: “Dimming doesn’t assume all pollution”..............................................................................................61 Dimming-AT: Asian SO2 Solves..................................................................................................................................62 AT: Air Pollution = Disease..........................................................................................................................................63 AT: Aerosols = Famine.................................................................................................................................................64 AT: Aerosols Not Check Warming / Aerosols Studies..................................................................................................65 AT: Methodology Problems..........................................................................................................................................66 AT: Only Delay Impacts...............................................................................................................................................67 ***DIMMING / SO2 BAD..........................................................................................................................................68 SO2/Dimming Low Now [1/2].....................................................................................................................................69 SO2/Dimming Low Now [2/3].....................................................................................................................................70 SO2/Dimming Low Now [3/3].....................................................................................................................................71 Aerosols/FF’s = Acid Rain............................................................................................................................................72 SO2=Acidic Oceans......................................................................................................................................................73 Acid Rain hurts oceans [1/2].........................................................................................................................................74 Acid Rain hurts oceans [2/2].........................................................................................................................................75 Acid Rain - Ocean destruction=Extinction...................................................................................................................76 Acid Rain-Kills Coral [1/2]..........................................................................................................................................77 Acid Rain-Kills Coral [2/2]..........................................................................................................................................78 Acid Rain-Coral k2 Bio-D............................................................................................................................................79 Acid Rain-Destroys Forest ...........................................................................................................................................80 Dimming Bad-Dimming=Famine.................................................................................................................................82 Aerosols = Famine........................................................................................................................................................83 Aerosols = Famine, Drought.........................................................................................................................................84 Aerosols Bad - SLR, Drought, Famine.........................................................................................................................85 Dimming=Drought [1/2]...............................................................................................................................................86 Dimming=Drought Impact - War[2/2]..........................................................................................................................87 .......................................................................................................................................................................................87 Dimming Bad-SO2 Kills thousands..............................................................................................................................88 ***OTHER AFF ANSWERS.......................................................................................................................................89 AT: Dimming Solves Plankton ....................................................................................................................................90 AT: Dimming solves marine ecosystems......................................................................................................................92 AT: Dimming Solves Disease.......................................................................................................................................93 AT: Dimming solves drought........................................................................................................................................94 AT: Dimming-Not a developing problem.....................................................................................................................95 AT: Dimming-Not conclusive.......................................................................................................................................96 AT: Dimming-Aerosols=More warming-Black Carbon...............................................................................................97 AT: Dimming-Aerosols 90% natural............................................................................................................................98 AT: Dimming-Asia SO2 solves [1/2]............................................................................................................................99 AT: Dimming-Asia SO2 Solves [2/2].........................................................................................................................100 AT: “Cool waters mean we solve sea level”...............................................................................................................101 Coal Aerosols Not Offset Warming............................................................................................................................102 Aerosols = Disease......................................................................................................................................................103 Black Soot Counterbalancing.....................................................................................................................................104

Gonzaga Debate Institute 2008 Scholars

***SO2/DIMMING DA

3 Aerosols

Gonzaga Debate Institute 2008 Scholars

4 Aerosols

1NC SO2/Dimming DA [1/2] A) Aerosols are holding off global warming now Warren`8 (Matthew, Enviromental Writer for the Australian, Temperatures tipped to pause for a decade, May 2, 2008 Friday, Lexis)

RISING global temperatures may stall for the next decade, with some scientists now believing the natural response of ocean currents will temporarily offset the effects of climate change. German climate scientists say the temperature pause is the result of the slowing of the global currents that transport heat around the planet. Their research, in the latest edition of the journal Nature, is an attempt to more accurately forecast global temperature changes and variations on a shorter time scale. Climate modellers from the Leibniz Institute for Marine Sciences and the Max Planck Institute for Meteorology have stressed they do not directly contradict the projections of the Intergovernmental Panel on Climate Change, which last year estimated temperature increases of about 0.2C a decade over the next 20 years. The research suggests a cooling diversion for the next 15 to 20

years after which there is likely to be accelerated temperature increases as global warming overrides the cooling effect. ``In the short term, you can see changes in the global mean temperature that you might not expect given the reports of the Intergovernmental Panel on Climate Change,'' Noel Keenlyside from the Leibniz Institute of Marine Sciences told the BBC. ``In the long term, radiative forcing dominates. But it's important for policymakers to realise the pattern.'' The latest research illustrates the complexity and uncertainty in trying to model the specific behaviour of the oceans. Research released by the CSIRO in January predicted an acceleration, rather than a slowing, of the earth's currents caused by increased pollution in the northern hemisphere. CSIRO's Wenju Cai and Tim Cowan found that these pollutants or aerosols cool the ocean surface in the northern hemisphere, causing an imbalance that is redressed by an acceleration of these global currents. This effect is called global dimming. Dr Cai said his theory was not completely at odds with the latest German research, as both would result in relative cooling across the northern hemisphere. ``Aerosols are mitigating the warming -without them we could have warmed more, and there is a net cooling effect from aerosols and that is going to intensify the gulf stream,'' he said. Other scientists have questioned the research, saying the slowing of the currents may be caused by changes in the saltiness of ocean waters.

B) Reducing greenhouse gases cuts SO2 and other cooling aerosols EDIE`99Environmental Data Interactive Exchange 6/99 http://www.edie.net/news/news_story.asp?id=1404 "In the atmosphere, sulphur dioxide gas emitted by burning coal and oil is converted into sulphate aerosols that enhance the reflection of solar radiation, thereby tending to cool Earth's surface," said Michael Schlesinger, an atmospheric scientist at the University of Illinois. "In recent studies, we found that decreasing the sulphur dioxide emissions led to significant regional warming in North America, Europe and Asia." The studies were based on provisional greenhouse-gas and sulphur dioxide emissions developed by the Intergovernmental Panel on Climate Change. The IPCC is producing a Special Report on Emissions Scenarios, in part as background for the IPCC Third Assessment Report scheduled to be completed in 2001. In the special report there are four scenario families for the future emissions of greenhouse gases and sulphur dioxide. To explore the potential effects, Schlesinger and colleagues first used a simple climate/ocean model to calculate the change in global-mean surface temperature for the sulphur dioxide emissions of the four Special Report scenarios, as well as for the non-interventionist IS92a scenario of the IPCC Second Assessment Report. "These global-mean temperatures were then used to scale the geographical distributions of temperature change simulated by our atmospheric general circulation/mixed-layer-ocean model for a tenfold increase in present-day sulphur dioxide emissions, both individually and jointly from six geographical regions," Schlesinger said. The increasing sulphur dioxide emissions of the IS92a scenario result in a cooling contribution that helps to offset some of the greenhouse gas-induced warming, Schlesinger said, but the decreasing sulphur dioxide emissions of the four SRES scenarios result in the opposite:

a significant warming of portions of North America, Europe and the North Atlantic, and Siberia. "Thus it appears that mitigation of the acid-rain problem by future reductions in sulphur dioxide emissions exacerbates the greenhouse-warming problem by enhancing the warming in and near the regions where the sulphur dioxide emissions are reduced," Schlesinger said.

Gonzaga Debate Institute 2008

5 Aerosols

Scholars

1NC SO2/Dimming DA [2/2] C) Reducing aerosols causes rapid and catastrophic global warming BBC`6 (Brittish Broadcasting Corporation, Transcript of the documentary

“Global Dimming”

http://www.informationclearinghouse.info/article15809.htm)

NARRATOR: If so much could happen in such a short time, removing just one form of pollution, then it suggests that the overall effect of Global Dimming on world temperatures could be huge. DR DAVID TRAVIS: The nine eleven study showed that if you remove a contributor to Global Dimming, jet contrails, just for a three day period, we see an immediate response of the surface of temperature. Do the same thing globally we might see a large scale increase in global warming. NARRATOR: This is the real sting in the tail. Solve the problem of Global Dimming and the world could get considerably hotter. And this is not just theory, it may already be happening. In Western Europe the steps we have taken to cut air pollution have started to bear fruit in a noticeable improvement in air quality and even a slight reduction in Global Dimming over the last few years. Yet at the same time, after decades in which they held steady, European temperatures have started rapidly to rise culminating in the savage summer of 2003. Forest fires devastated Portugal. Glaciers melted in the Alps. And in France people died by the thousand. Could this be the penalty of reducing Global Dimming without tackling the root cause of global warming? DR BEATE LIEPERT: We thought we live in a global warming world, um but this is actually er not right. We lived in a global warming plus a Global Dimming world, and now we are taking out Global Dimming. So we end up with the global warming world, which will be much worse than we thought it will be, much hotter. NARRATOR: This is the crux of the problem. While the greenhouse effect has been warming the planet, it now seems Global Dimming has been cooling it down. So the warming caused by carbon dioxide has been hidden from us by the cooling from air pollution. But that situation is now starting to change. DR PETER COX (Hadley Centre, Met Office): We're gonna be in a situation unless we act where the cooling pollutant is dropping off while the warming pollutant is going up, CO2 will be going up and particles will be dropping off and that means we'll get an accelerated warming. We'll get a double whammy, we'll get, we'll get reducing cooling and increased heating at the same time and that's, that's a problem for us.

Gonzaga Debate Institute 2008 Scholars

6 Aerosols

Dimming-Uniqueness-Block Extension/A2: CAA Everyone violates the clean air act-Emissions are up a) Pfizer Wall Street Journal`8 (Kathy Swiff, Pfizer Will Pay $975,000 to Settle Claim of Clean Air Act Violation, June 23, 2008, http://online.wsj.com/article/SB121424294109297171.html?mod=googlenews_wsj)

Pfizer Inc. will pay $975,000 to settle alleged violations of the Clean Air Act at a former manufacturing plant in Groton, Conn. The federal government said the civil settlement is the first in federal court under regulations designed to control the emissions of hazardous air pollutants from pharmaceutical-manufacturing operations. Pfizer spokesman Chris Loder said the world's largest drug maker agreed to settle even though it does not believe the penalty was "commensurate with the nature of the alleged violations."

b) Mercedes-Chrysler Consumer Affairs`6 (Consumer Affairs.com, Consumer information website, Mercedes-Benz Fined for Clean Air Act Violation December 21, 2006 http://www.consumeraffairs.com/news04/2006/12/epa_mercedes.html)

Mercedes-Benz USA and its parent corporation, DaimlerChrysler AG, have agreed to pay $1.2 million in civil penalties to resolve allegations that they violated the Clean Air Act. The companies failed to promptly notify the Environmental Protection Agency (EPA) about defects in the air pollution controls installed on numerous 1998 to 2006 Mercedes model vehicles, according to the Justice Department and the EPA.[Paragraphs down] "Mercedes' failure to alert EPA to a number of defects in emission-related components over a multi-year period is a serious violation because it deprived EPA of the opportunity to promptly determine whether emission standards would be exceeded and whether to order a recall of any of these vehicles," Wooldridge added. "These defect reporting requirements are a critical part of EPA's program to ensure that vehicles on the road comply with the Clean Air Act's emissions standards," said Catherine R. McCabe, Principal Deputy Assistant Administrator for the EPA's Office of Enforcement and Compliance Assurance.

c) CITGO Environmental News Service`7 (Environment News Service is the original daily newswire of the environment, since 1990. CITGO Guilty of Criminal Clean Air Act ViolationsEnvironment News Service, June, 2007 http://findarticles.com/p/articles/mi_kmens/is_200706/ai_n19332983)

A federal jury in Corpus Christi has found CITGO Petroleum Corp., and its subsidiary, CITGO Refining and Chemicals Co., guilty of two felony criminal violations of the Clean Air Act. CITGO was convicted on two counts of operating two huge open top tanks, 116 and 117, without installing the proper emission controls required by state and federal regulations at its Corpus Christi East Plant Refinery. Virtually no oil should have been found in the two tanks that were part of the refinery wastewater treatment system if the tanks were being operated as designed. CITGO learned after the two tanks were built, that large volumes of oil were accumulating in the two tanks in violation of state and federal regulations. Modifications to the up-stream operations were not successful at keeping oil out of the two tanks.

d) DuPont Environmental Leader`7 (Environmental Leader, July 24, 2007Clean Air Act Violations Cost DuPont $70 Million http://www.environmentalleader.com/2007/07/24/clean-air-act-violations-cost-dupont-70-million/)

The Department of Justice and EPA have reached a settlement with DuPont that is expected to reduce more than 13,000 tons of emissions annually from four sulfuric acid production plants in Louisiana, Virginia, Ohio and Kentucky. DuPont will spend at least $66 million on air pollution controls at the plants and pay a civil penalty of $4.125 million under the Clean Air Act settlement. When fully implemented, the settlement with DuPont will reduce sulfur dioxide emissions from the four plants by approximately 90 percent. The government’s complaint (PDF), filed today with the consent decree (PDF), alleges that DuPont made modifications to its plants which increased emissions of sulfur dioxide without first obtaining pre-construction permits and installing required pollution control equipment.

Gonzaga Debate Institute 2008 Scholars

7 Aerosols

Dimming-Uniqueness-Fossil Fuel Use High Now [1/2] Fossil Fuel use high now-It’s a trend AP`8 (Associated Press, Joseph Herbert, Report sees big jump in energy, fossil fuel use June 25, 2008, http://ap.google.com/article/ALeqM5gUMV8UJoaN5q_kTW2qE60EkyYQZQD91H660O1)

Despite persistently high oil prices, global energy demand will grow by 50 percent over the next two decades with continued heavy reliance on environmentally troublesome fossil fuels, especially coal and oil, the government predicted Wednesday. The report forecast the steepest increases in China and other emerging economies where energy demand is expected to be 85 percent greater in 2030 than it is today. "What jumps out is the very strong growth in the emerging economies," said Guy Caruso, head of the federal Energy Information Administration, which conducted the long-term energy outlook. The projections said that without mandatory actions to address global warming, the amount of heat-trapping carbon dioxide flowing into the atmosphere each year from energy use will be 51 percent greater in 2030 than it was three years ago. "Fossil fuels ... are expected to continue supplying much of the energy used worldwide," the report predicts, in spite of the growth of renewable energy sources, especial wind and biofuels. "Global energy demand grows despite the sustained high world oil prices that are projected to persist over the long term," said the report. Oil could cost as little as $113 a barrel or as much as $186 a barrel in 2030, the analysis assumed in making the demand forecast. Adjusted for inflation, the $113 price would be about $70 in 2006 dollars, the report said. "We're not going back to the historically low prices we saw in the '80s and '90s," said Caruso. He said the EIA price estimates are not firm predictions, but assumptions of what costs are likely to be in the long term. The report provided both high and low price scenarios because of the uncertainties of projecting future long-term energy prices. Given current oil prices, the report says world oil prices appear on a path that more closely resembles the higher price scenario of $183 a barrel oil in 22 years. Caruso said the analysis shows the importance of oil prices over the long term. He said while oil consumption will increase, the forecast

projects demand to be about 10 million barrels a day less at the higher price assumption. Still, the report predicted continued growth of petroleum use in transportation and heavy coal use to produce electricity. The report assumes in its analysis no additional measures to curtail carbon dioxide emissions to address climate change. The expected growth in energy demand is especially dramatic in developing countries, led by China, that are expected to have continued strong economic growth over the next two decades. For example, the use of coal worldwide is expected to increase at a rate of 2 percent a year. China alone will account for nearly three-fourths of that increase, the report said. Despite coal burning's significant impact on climate change "it's the fuel of choice for electricity production in the emerging economies, especially China," Caruso said at a meeting held by the Center for Strategic and International Studies. The world's demand for liquid fuels — mostly oil — will continue to grow to 113 million barrels a day by 2030, nearly a third more than is consumed today. Unconventional oil such as oil shale and biofuels such as ethanol should grow to nearly 10 percent of total liquid fuels. Still, with continued demand for conventional crude oil, the OPEC cartel is expected to increase production at a pace that will keep its 40 percent market share, the report predicts.

Fossil Fuel emissions will grow by 50% IPS`8 (International Press Service, Abid Aslam, ENERGY: U.S. Sees World Use Soaring Despite Rising Costs, June 25, 2008, http://www.ipsnews.net/news.asp?idnews=42968)

World energy demand and carbon dioxide emissions will grow by about 50 percent over the next two decades despite soaring oil prices as developing countries outpace rich ones in consumption, the U.S. government predicts. "World marketed energy consumption is projected to increase by 57 percent from 2004 to 2030," the Energy Information Administration (EIA) says in its International Energy Outlook 2008 report, released Wednesday. Referring to the wealthy nations' Organisation for Economic Cooperation and Development (OECD), it adds that during the same period, "total energy demand in the non-OECD countries increases by 95 percent, compared with an increase of 24 percent in the OECD countries." The report sees non-OECD countries' share of world energy consumption rising from 47.9 percent in 2005 to 58.8 percent in 2030. Oil and coal -- both regarded as major culprits in global warming because of the carbon dioxide they spew into the atmosphere when burned -- will continue to dominate global energy supply, says the U.S. Energy Department's statistical wing. As a consequence, and assuming no new measures are enacted to curb climate change, the annual amount of heat-trapping carbon dioxide flowing from energy use will have ballooned by 51 percent between 2005 and 2030. "Global energy demand grows despite the sustained high world oil prices that are projected to persist over the long term," says the report. It sees the price of oil standing at somewhere between 113 dollars a barrel and 186 dollars a barrel. While long-term prices are difficult to predict, it adds, current trends favour the higher projection of 183 dollars a barrel. Today's price hovers around 137 dollars. Regardless of the rising cost involved, the EIA says, growth in petroleum use will be driven by the transportation sector and electricity producers will rely heavily on coal.

Gonzaga Debate Institute 2008 Scholars

8 Aerosols

Dimming-Fossil fuels=Aerosols Burning fossil fuels increases aerosol concentration, and produces cooling Science Daily`4 (Science Daily, syndicated science magazine, Burning Fossil Fuels Has A Measurable Cooling Effect On The Climate, Jan. 19, 2004, http://www.sciencedaily.com/releases/2004/01/040119082910.htm)

Atmospheric researchers have provided observational evidence that burning fossil fuels has a direct impact on the solar radiation reflectivity of clouds, thereby contributing to global climate change. Joyce Penner, professor in the University of Michigan Department of Atmospheric, Oceanic and Space Sciences, U-M graduate student Yang Chen, and assistant professor Xiquan Dong from the University of North Dakota Department of Atmospheric Science, reported their findings in the Jan. 15 issue of the journal Nature. Most evidence that increased levels of fossil fuel particles (aerosols) affects the reflectivity of clouds, thereby producing a cooling effect on the climate, has been indirect. "This made it difficult to determine the impact this phenomena, known as the indirect aerosol effect, has on the global climate," Penner said. "Our data makes the direct connection and opens new areas of study." Solar radiation, which adds to global warming, is reflected back into space by clouds. Cloud droplets are increased with higher levels of aerosols, allowing for less radiation, or heat, to reach the lower atmosphere. The end result is a measurable cooling effect on the climate. Using atmospheric data gathered from a site in Oklahoma, a typical continental site with a high concentration of aerosols, and a typical Arctic site in Barrow Alaska with low aerosol concentration, the researchers were able to show that the difference in cloud reflectivity at the two sites was caused by the difference in aerosol levels. The researchers also provided important evidence that the computer simulation model used in the study was capable of estimating cloud optical properties determined over a broad range of aerosol concentrations. "This study is important for two reasons," Penner said. "First, it provides evidence that there is some cooling of the climate due to anthropogenic aerosols. Second, the simulation model we used has been shown to be a valuable tool in determining more directly the impact of aerosols on the climate."

Gonzaga Debate Institute 2008 Scholars

9 Aerosols

Dimming-Aerosols k2 Dimming Aerosols key to global dimming Appell`4(David, Ph.D. Plant Pathology, The Darkening Earth Less sun at the Earth's surface complicates climate models, The Scientific American, August, 2004 http://www.sciam.com/article.cfm?id=the-darkening-earth)

Sometimes called global dimming, the reduction in solar radiation varies from region to region, and no measurements have yet been made over the world's oceans. It has also been deduced from evaporation rates around the world-the amount of water that evaporates from specially calibrated pans has been dropping for at least five decades in the Northern Hemisphere. At the May American Geophysical Union meeting in Montreal, Michael Roderick and Graham Farquhar of the Australian National University presented results that extend the finding across the Southern Hemisphere as well. A key culprit appears to be aerosols-micron-size particles (or smaller) consisting of sulfates, black and organic carbon, dust, and even sea salt. Aerosols have already been implicated in cooling tendencies, such as the slight decrease in global temperatures seen from about 1945 to 1975. Besides keeping temperatures from rising even higher than they already have, the aerosols complicate the modeling of global warming. The particulates act as the nuclei points for cloud condensation. They can lead to more cloudiness--a phenomenon called the indirect aerosol effect--which reflects sunlight away.

Gonzaga Debate Institute 2008 Scholars

10 Aerosols

Dimming-Warming pollutants = Dimming The fuels that cause global warming cause global dimming Schueneman`7(Thomas D., Global Dimming , Turning Down The Sun, May 7 2007, http://climatechange.suite101.com/article.cfm/global_dimming)

Global dimming is the ironic counterpoint to global warming, both caused from burning fossil fuels, and both a serious potential threat to our future climate. The sun shines down on the Earth, providing two of the essential elements of life: light and heat. But we live in a world of “quanta”; of measurable matter and energy. Thus, the sunlight radiating upon the earth is a matter of specific measurement. These specific measurements of the quantity of sunlight reaching the Earth’s surface did not begin in any scientifically viable way until the 1950’s. Since then, the ongoing measurement shows a steady decline of solar irradiance. A "Global Dimming" of the sun of an average of 4% between 1960 and 1990. Global dimming was first discovered by English Scientist Gerry Stanhill. Working in Israel, Stanhill compared records from the 1950’s with recent measurements and found, to his astonishment, a 22% decrease in sunlight . This led to further investigations and just about everywhere he looked he found the same phenomenon: a 10% decrease over the United States, nearly 30% over the former Soviet Union, 16% over portions of the British Isles. Despite the wide regional variation of decreased sunlight, the decline has been averaged to 1-2% per decade from the 1950’s to the 1990’s. The cause of the dimming is believed to be from the increased presence in the atmosphere of particulate matter and aerosols from burning fossil fuels and other human activity. This particulate matter absorbs and reflects sunlight. The effect of solar “dimming” by virtue of dirty air is somewhat expected. More unexpected and surprising to scientists is how these particles alter the reflective properties of clouds. The reflectivity of a cloud depends on the surface area of the droplets within it. The aerosols and other particles in polluted clouds create smaller water droplets than in unpolluted clouds; up to six times as many droplets. The actual amount of water vapor does not change, but the increased number of droplets makes the clouds more reflective, thus radiating more sunlight back into space before reaching the Earth’s surface.

Fossil fuel use =Global Dimming Sington`5(David, BBC Horizon Producer, Why the Sun seems to be 'dimming', 13 January 2005http://news.bbc.co.uk/1/hi/sci/tech/4171591.stm)

Comparing Israeli sunlight records from the 1950s with current ones, Dr Stanhill was astonished to find a large fall in solar radiation. "There was a staggering 22% drop in the sunlight, and that really amazed me." Intrigued, he searched records from all around the world, and found the same story almost everywhere he looked. Sunlight was falling by 10% over the USA, nearly 30% in parts of the former Soviet Union, and even by 16% in parts of the British Isles. Although the effect varied greatly from place to place, overall the decline amounted to one to two per cent globally every decade between the 1950s and the 1990s. Dr Stanhill called it "global dimming", but his research, published in 2001, met a sceptical response from other scientists. It was only recently, when his conclusions were confirmed by Australian scientists using a completely different method to estimate solar radiation, that climate scientists at last woke up to the reality of global dimming. Dimming appears to be caused by air pollution. Burning coal, oil and wood, whether in cars, power stations or cooking fires, produces not only invisible carbon dioxide - the principal greenhouse gas responsible for global warming - but also tiny airborne particles of soot, ash, sulphur compounds and other pollutants. This visible air pollution reflects sunlight back into space, preventing it reaching the surface. But the pollution also changes the optical properties of clouds. Because the particles seed the formation of water droplets, polluted clouds contain a larger number of droplets than unpolluted clouds. Recent research shows that this makes them more reflective than they would otherwise be, again reflecting the Sun's rays back into space.

Gonzaga Debate Institute 2008 Scholars

11 Aerosols

Dimming ⇓ solvency Ignoring the dimming of aerosols guts solvency by making climate models unpredictable Tay`7 (Sheralyn, Writer for Wild Singapore environmentalist website, Shedding some light on global dimming, April 6, 2007, http://www.wildsingapore.com/news/20070304/070406-2.htm)

GLOBAL warming is only half the story, there's another phenomenon we're in the dark about — literally. Too many pollutants in the air causes a reduction of sunlight getting through the atmosphere, an effect known as global dimming. And Singaporeans are already feeling its effect — when the haze comes blowing. "When Indonesia burns, the haze causes the effect of global dimming and blocks out the sunlight," said Dr John Yong, Assistant Professor of Natural Sciences and Science Education at the Nanyang Technological University's National Institute of Education. This dimming effect reduces the amount of sunlight that reaches the earth, making it seem cooler, but also masking the full effect of global warming. One area where the impact of global dimming on climate change can easily be seen: Air travel. According to Dr Yong, the "911 effect" was discovered in the days just after the terrorist attacks on the World Trade Center in the United States on Sept 11, 2001. "All air travel stopped, and what happened? The temperature went up!" Dr Yong said. Climate scientists, who had previously theorised that aircraft vapour trails were related to global dimming, noted that the absence of these trails correlated to an increase of about 1°C in the daily temperature in parts of the United States. "So, in a way, we have pollutants to thank for protecting us from global warming," said Dr Yong with a laugh. Between the '50s and the '90s, British scientist Gerry Stanhill found that the amount of sunlight reaching the earth fell by between 10 and 30 per cent in different parts of the world. The rate of dimming varied but scientists believe it to drop by an average of around 2 to 3 per cent each decade. While there are no estimates for Singapore, statistics from around Asia put the dimming effect to be about 10 to 37 per cent, with Hong Kong facing the worst effects. Global dimming also has serious repercussions on agriculture. "With less sunlight, there will be less photosynthesis (the manner in which plants make food) and this will affect the food chain," said Dr Yong.In addition, the particulate matters (PM), those nano-sized particles that cause the dimming effect, have a significant impact on health. PM10 and PM2.5 — particulate matter that is smaller than 10 or 2.5 microns, respectively — are associated with respiratory illness and even cancer. All this creates a dilemma for scientists trying to deal with global dimming. "If we clean up the air, you'll have a big heat problem," Dr Yong said, citing heat waves in Europe that may be linked to the continent's efforts to cut down on emissions of particulate matters. "There must be a concerted effort to clean the air and be carbon-neutral. If not, when you just clear the nano-particulates it will be very hot, but if you reduce carbon emissions only, crops will still fail, so both of these must be done in tandem. There's the headache," he said.

Gonzaga Debate Institute 2008 Scholars

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Dimming Good-Solves Warming [1/3] Dimming key to solve runaway warming Pelow`4 (Mark, Macmillan Magazines Energy Bulletin, Look forward to a darker world, 'Global dimming' may stop the Earth overheating. May 18 2004 http://energybulletin.net/node/339)

Michael Roderick and Graham Farquhar from the Australian National University in Canberra found that evaporation rates across Australia, measured using continually replenished pans of water, have fallen significantly over the last 30 years, a sure sign that less direct sunlight is reaching the surface. The decline matches the effect seen in the northern hemisphere. "This proves that it is a global phenomenon," says Roderick. But he is not dismayed by the result. He has recently advised the Australian government that global dimming may not necessarily be a bad thing. "The standard dogma is that Australia will dry out [with global warming], but that's just not right. The world is actually getting less arid," he insists. In fact, Roderick sees global dimming as part of a possible negative feedback loop working against global warming. Burning fossil fuels not only increases carbon dioxide levels in the atmosphere; it also pumps tiny particles into the air. Meanwhile higher temperatures increase the amount of cloud cover. The clouds and particles help to block the Sun's rays, and the scattered light they allow through actually boosts plants' absorption of carbon dioxide, the principle greenhouse gas. This would help to keep carbon dioxide levels stable, argues Roderick, protecting the planet from runaway global warming

Dimming is the last barrier to climate collapse The Age`8( The Age, European Based World news network, Flannery proposes 'global dimming' to save planet, May 19 2008, http://www.theage.com.au/news/global-warming/radical-plan-to-save-planet/2008/05/19/1211182701986.html)

Scientist Tim Flannery has proposed a radical solution to climate change which may change the colour of the sky. But he says it may be necessary, as the "last barrier to climate collapse." Professor Flannery says climate change is happening so quickly that mankind may need to pump sulphur into the atmosphere to survive. Australia's best-known expert on global warming has updated his climate forecast for the world - and it's much worse than he thought just three years ago. He has called for a radical suite of emergency measures to be put in place. The gas sulphur could be inserted into the earth's stratosphere to keep out the sun's rays and slow global warming, a process called global dimming. "It would change the colour of the sky," Professor Flannery told AAP. "It's the last resort that we have, it's the last barrier to a climate collapse." "We need to be ready to start doing it in perhaps five years time if we fail to achieve what we're trying to achieve." Professor Flannery, the 2007 Australian of the Year, said the sulphur could be dispersed above the earth's surface by adding it to jet fuel.

Dimming solves warming-Proves predictions wrong BBC`5(British Broadcasting Station, Global Dimming, 21/03/2005http://www.abc.net.au/4corners/content/2005/s1325819.htm)

Essentially, the phenomenon called "global dimming" may mean that even the direst predictions about the rate of global warming have been seriously underestimated. Until recently many scientists had never heard of global dimming. Among those who had, a lot remained sceptical. Now, thanks in part to the work of Australian researchers, the debate is set to edge into public consciousness. This special report from the BBC’s Horizon program reveals how global dimming was gradually unmasked by isolated groups of scientists across the world ... in Israel, Germany, the US and Australia. Global dimming is a product of the fossil fuels that cause global warming. It is the result of tiny airborne pieces of soot, ash and sulphur compounds reflecting back the heat of the sun. By allowing less sunlight to reach the Earth, global dimming is cushioning us from the full impact of global warming, climatologists say. They fear that as we burn coal and oil more cleanly, and dimming is reduced, the full effects of global warming will be unleashed. The worst-case scenario has temperatures rising by up to 10 degrees by the end of the century – twice more than previously thought.

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Dimming Good-Solves Warming [2/3] Dimming solves warming-Without it all their warming analysis is wrong Macintosh`7 (Craig, Writer for Celcias-Climate awareness organization, Veiling Our True Predicament: Part I - Global Dimming, May 2007 http://www.celsias.com/article/veiling-our-true-predicament-part-i-global-dimming/)

That is exactly what makes this discovery so alarming.... Global dimming has slowed the impact of global warming. Global warming and global dimming, like two deadly arch-villains from a fantasy comic, have been fighting each other for supremacy over the earth - each bringing its own kind of destruction to us, but with the promise of a far more focused effort against humanity when that supremacy has been made final. At least, that was the case until the late 1980s. After this point, global efforts to minimise aerosols, as well as other factors (like, potentially, the major economic crash in the former USSR and its captive eastern-bloc states) have slowed aerosol releases - pulling back the veil on the sun's rays, and allowing global warming to gain the upper hand, and momentum. The result of global dimming discoveries is a gradual awakening to a few sobering realities: Global dimming may well have softened the full impact of global warming - i.e. the currently observable impacts of Global Warming could be a lot greater if it wasn't for our smoggy skylines. As we clean up our skies through improved filtering systems and cleaner technologies, we are removing a 'check' on more rapid temperature increases - potentially unleashing a far fuller/faster fury of global warming. Many scientific temperature models for global warming have failed to take global dimming into the equation. Thus, even the inadequate reduction targets set by certain nations are now being seen as even more inadequate.

Dimming is shielding us from the worst impacts of warming now AC`7 (Associated Content.com, Stephanie Dray, Global Dimming: Why Pollution is Good, Up is Down and China is Our Best Friend, September 13, 2007, http://www.associatedcontent.com/article/371363/global_dimming_why_pollution_is_good.html?cat=9)

The idea of global dimming is simple-human beings are throwing so much filth into the air that we're blocking out the sunlight that would otherwise reach us and accelerate the already run-away process of global warming. Because we're trashing our planet and blotting out the sun, scientists calculate that we may actually be preventing about two degrees of planetary heat. Those two degrees may be the difference between our glib dismissal of an unprecedented number of category five storms as part of "the natural climate cycle" and our having to suffer the cataclysmic effects of global warming that a certain former Vice President has been warning about. In the first week of September, NOVA aired an investigative program entitled "The Dimming of the Sun." In it, scientists discussed their findings that only a few days of suspended air travel in the aftermath of September 11th resulted in a marked temperature change in the atmosphere, indicating that the effects of American atmospheric pollution have been vastly underestimated to date.

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Dimming Good-Solves Warming [3/3] Surface cooling aerosols cut the impact of global warming in half Ramanathan`7(V, Scripps Institution of Oceanography University of California at San Diego 5/07) The global build up of greenhouse gases (GHGs), is the most vexing global environmental issue facing the planet. GHGs warm the surface and the atmosphere with significant implications for, rainfall, retreat of glaciers and sea ice, sea level, among other factors. What is less recognized, however, is a comparably major global problem dealing with air pollution. Until about ten years ago, air pollution was thought to be just an urban or a local problem. But new data have revealed that, due to fast long range transport, air pollution is transported across continents and ocean basins, resulting in trans-oceanic and trans-continental plumes of atmospheric brown clouds (ABCs) containing sub micron size particles, i.e, aerosols. ABCs intercept sunlight by absorbing as well as reflecting it, both of which, lead to a large surface dimming. The dimming effect is enhanced further because aerosols nucleate more cloud drops which makes the clouds reflect more solar radiation. The surface cooling from this dimming effect has masked the warming due to GHGs. ABCs are concentrated in regional and mega-city hot spots. Long range transport from these hot spots gives rise to wide spread plumes over the adjacent oceans. Such a pattern of regionally concentrated surface dimming and atmospheric solar heating, accompanied by wide spread dimming over the oceans, gives rise to large regional effects. Only during the last decade, we have begun to comprehend the surprisingly large regional impacts. The large north-south gradient in the ABC dimming has altered the north-south gradients in sea surface temperatures, which in turn has been shown by models to decrease rainfall over the continents. In addition to their climate effects, ABCs lead to acidification of rain and also result in over few million fatalities worldwide. The surface cooling effect of ABCs may have masked as much 50% of the global warming. This presents a dilemma since efforts to curb air pollution may unmask the ABC cooling effect and enhance the surface warming. Thus efforts to curb GHGs and air pollution should be done under one framework.. The uncertainties in our understanding of the ABC effects are large, but we are discovering new ways in which human activities are changing the climate and the environment.

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Dimming = Negative Feedback Warming burns itself out-It produces dimming Western Daily Press`3 (Western Daily Press, Is Plunging The World Into Darkness December 19, 2003, Lexis) The dimmer switch has been flicked on Earth as global warming blocks sunlight, experts warned yesterday. In recent years, the level of rays breaking through to the surface of the planet has fallen by one fifth, and the effect is growing year on year. Scientists at Nasa claim pollution is not only heating up the atmosphere, it is making the Earth darker. Global warming is said to produce more and longer-lasting cloud cover, creating a barrier to brightness. Climate experts believe it could impact on the growth of trees and plants and the effectiveness of solar power. Dr Jim Hansen, from Nasa's Goddard Institute for Space Science in New York, said: "Over the past couple of years it has become clear that the solar irradiance at the Earth's surface has decreased." Light intensity has been recorded all over the world with reports showing a marked loss of illumination. One study indicated the level of natural light in Japan - land of the rising sun - was falling. Another reported that Ireland had experienced a decline in sunshine. The effect was strongest in the former USSR where solar radiation has fallen 20 per cent in 27 years. Light deterioration has been partly blamed on black carbon, microscopic particles of soot or chemical compounds produced from pollution. Trapped in the atmosphere, they act to reflect sunlight. "Data from a hundred stations around the world show that the amount of black carbon in the atmosphere is twice as big as we assumed," said Dr Hansen. Black carbon is released from inefficient diesel engines, unfiltered power plants or burning forest. People may be oblivious to so-called global dimming, which tends to occur during cloudy periods. Shabtai Cohen, who works at the Vocani Centre in Israel, said: "The cloudy times are getting darker. If it's cloudy then it's darker, but when it's sunny things have not changed much." Experts say the impact of reduced solar radiance may be greater in overcast areas of the northern hemisphere, such as Britain and Europe. Dr Cohen said: "In greenhouses in Holland, the rule of thumb is that a one per cent decrease in solar radiation equals a one per cent drop in productivity. "Because they are light limited they're always very busy cleaning the tops of their greenhouses."

Warming can cause dimming The Guardian`3 (The Guardian.com, David Adam, Goodbye sunshine, December 18, 2003, http://www.guardian.co.uk/science/2003/dec/18/science.research1)

It's also possible that global dimming is not entirely down to air pollution. "I don't think that aerosols by themselves would be able to produce this amount of global dimming," says Farquhar. Global warming itself might also be playing a role, he suggests, by perhaps forcing more water to be evaporated from the oceans and then blown onshore (although the evidence on land suggests otherwise). "If the greenhouse effect causes global dimming then that really changes the perspective," he says. In other words, while it keeps getting warmer it might keep getting darker. "I'm not saying it definitely is that, I'm just raising the question."

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Dimming-Reducing aerosols=More warming Reducing current aerosols=More warming Real Climate`5 (Real Climate.com, 18 January 2005 Global Dimming?, http://www.realclimate.org/index.php?p=105) Aerosols are however much more clearly responsible for serious respiratory problems in big cities (London prior to 1950s, Beijing today), and their health impacts are well known. This was one of the big pushes behind initiatives like the Clean Air acts in many countries which reduced aerosol emissions from power stations. While in the developed world (US, Europe, the ex-USSR) emissions have been falling, the global burden is increasing because of development in India and China. Since, on average, aerosols have a cooling effect (although some absorbing aerosols like black carbon (soot) are actually adding to global warming), reducing current aerosol levels (particularly sulphates) is equivalent to an extra warming effect.

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Aerosols Solve Warming – IPCC Concurs Fossil fuel consumption produces aerosols that counteract greenhouse gases, even the IPCC concedes that aerosols provide cooling to counteract warming Miller and Koch 2006 (Ron Miller and Dorothy Koch, NASA GISS Atmospheric Study Group, “An Aerosol Tour de Forcing”, February 8, 2006, http://www.realclimate.org/index.php/archives/2006/02/an-aerosol-tour-de-forcing/) Aerosols are solid particles or liquid droplets that are temporarily suspended within the atmosphere. Naturally occurring examples are sea spray or sulfate droplets, along with soil particles (dust) eroded by the wind. During the twentieth century, natural sources of sulfate aerosols were overwhelmed by the contribution from pollution, in particular from the burning of fossil fuels. The number of soot particles in the atmosphere was increased by industry and the burning of forests to clear land for agriculture. Sulfate aerosols are reflective and act to cool the planet. Soot particles are also reflective, but can absorb sunlight and cause warming. Soot production is greater if combustion occurs at low temperatures, as with cooking fires or inefficient power generation. Aerosols also scatter longwave radiation, although this is significant only for larger aerosols like soil dust, and is neglected by all three of the studies discussed here. In addition to their ability to scatter radiation and change the net energy gain at the top of the atmosphere (the 'direct' effect), aerosols modify the reflectance and lifetime of clouds (the 'indirect' radiative effects). Aerosols act as nuclei for the condensation of water vapor, resulting in the distribution of water over a larger number of cloud droplets compared to condensation in clean air. This increases the cloud's ability to reflect sunlight, while increasing the number of droplet collisions required to form a raindrop large enough to fall out of the cloud, effectively increasing the cloud lifetime. Observations and models provide a weaker constraint upon the size of the indirect effects, so the studies discussed here confine themselves to calculating only the direct radiative effect of anthropogenic aerosols. According to the latest (2001) IPCC report, direct radiative forcing by anthropogenic aerosols cools the planet, but the forcing magnitude is highly uncertain, with a global, annual average between -0.35 and -1.35 W/m2 at the top of the atmosphere (TOA). The uncertainty of the total indirect effect is even larger. Aerosols eventually fall out of the atmosphere or are washed out by rainfall. The smaller particles having the largest radiative effect typically reside in the atmosphere for only a few days to a few weeks. This time is too short for them to be mixed uniformly throughout the globe (unlike CO2), so there are large regional variations in aerosol radiative forcing, with the largest effects predictably downwind of industrial centers like the east coast of North America, Europe, and East Asia. Consequently, aerosol effects upon climate are larger in particular regions, where they are key to understanding twentieth century climate change.

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Dimming Good-Solves Warming-Solves Rice [1/2] Warming kills rice production Economic Times`7 (Prabha Jagannathan, Global warming cooks rice’s prospects, 13 Feb, 2007, http://economictimes.indiatimes.com/Markets/Commodities/Global_warming_cooks_rices_prospects/RssArticleShow/arti cleshow/1601432.cms)

There’s a silent killer stalking your bowl of rice: heat. Global warming is not just changing the climate drastically the world over, it is actively threatening to lower the production of India’s — and Asia’s — key staple by at least 7% (over pre-determined levels) by 2020 and to a maximum of 60% by the end of the century. In fact, the scientific world views the threat of increasingly high temperatures to rice — now the principal crop for the country’s food security with 44.6 million ha area and 89 million tonnes in production — as a mammoth problem. Temperature is a major determinant of crop development and growth. Studies show that rice yields would dip 10% for every 1º C increase in minimum temperature during the growing season. Climatologists expect global mean air temperatures to go up 1.4-5.8º C by the end of the century depending on changes in greenhouse gas concentrations. In the worst case scenario, that could mean at least 60% reduction in yield per ha by the end of the century. At the current rate of population growth, the country’s rice production has to be enhanced to 122 million tonnes by 2020 to meet the increasing demand. Almost 90% of the world’s rice is produced and consumed in tropical Asia, and this factor alone is likely to force agri-research into rice varieties that are highly temperature tolerant, through cultivar screening and identifying higher tolerance. Extensive scientific studies presented at the International Rice Research Conference in October 2006 have contended that the results of climate change impact assessment show general rice yields being seriously adversely affected not just in north-west India, the food bowl, but countrywide. Results of a study on the simulated impact of climate change on rice production — conducted by Anima Biswal, PK Aggarwal and others of the Indian Agricultural Research Institute — indicated conclusively that while in the short term rice production may not be affected significantly, in the long term, climate change will have significant adverse impact on the country’s rice production. Another study, Recent trends in climate and impact of climate change on rice yields in north-west India, by Indian Agricultural Research Institute (IARI) scientists and researchers pegged the range of yield reduction from the technological determined level from 7% in 2020 to a significant 25% in 2080. The study used models with future climatic anomalies as inputs into the crop sensitivity model for five stations, based on district-level historical rice yield and monthly rainfall as well as the maximum temperatures (Tmax) and minimum temperatures (Tmin) for the past 30 years. It maintains, “Both Tmax and Tmin showed increasing trends at annual, kharif (summer) and rabi (winter) time scales with different rates. The rate of increase is significantly higher during kharif (the key rice production season in the country)than during rabi for Tmax and vice versa for Tmin.”

Warming kills rice CBS`4 (Global Warming Hurts Rice Yield Studies Show Increasing Temperatures Reduced Crop Yield For Rice WASHINGTON, June 28, 2004 http://www.cbsnews.com/stories/2004/06/28/tech/main626471.shtml)

Global warming could mean bad news for one of the world's most important crops, rice. Increased nighttime temperatures were associated with significant declines in crop yield at the International Rice Research Institute Farm in the Philippines, according to a report in Monday's issue of Proceedings of the National Academy of Sciences. Indeed, an average daily temperature increase of 1 degree Celsius resulted in a 10 percent reduction in the rice crop, according to the researchers. One degree Celsius equals about 1.8 degree Fahrenheit. Increasing temperatures, thought to be a result of heat trapped by industrial and other chemicals in the atmosphere, have caused mounting concern in recent years. Scientists have argued over the potential effects of climate change on crops, largely basing their contentions on laboratory tests and computer models of climate and crop yield. This new study was a direct measurement of yields under field conditions using practices that good farmers would employ, said lead researcher Kenneth G. Cassman of the University of Nebraska. Cassman and colleagues studied 12 years of rice yields at the farm, along with weather data, to reach their conclusions. The results are generally similar to findings reported last year following a 17-year study of U.S. crop yields. That study indicated that increases in temperature resulted in reductions in corn and soybean yields. Cassman said researchers are working to determine the cause of the reduction, but they speculate that it is because the hotter nights make the plants work harder just to maintain themselves, diverting energy from growth. "If you think about it, world records for

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Dimming Good-Solves Warming-Solves Rice [2/2] the marathon occur at cooler temperatures because it takes much more energy to maintain yourself when running at high temperatures. A similar phenomenon occurs with plants," he said. Tim L. Setter, a professor of soil, crop and atmospheric science at Cornell University, commented that higher nighttime temperatures "could consume carbohydrates in a nonproductive way, and by reducing the reserves of carbohydrates, particularly at time of flowering and early grain filling, would decrease the number of kernels that would be set." Setter, who was not a part of the rice research team, said a recent study in corn had shown that the number of kernels was decreased when researchers experimentally increased the night temperatures. Cassman commented that rice production has stagnated in recent years in some key producing regions of Asia. "That's something that hasn't been on the radar screen and needs to get more attention," he said. The new study was funded by the International Rice Research Institute and the Agricultural Research Division of the University of Nebraska.

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Dimming Good-Solves Drought-Solves Rice Drought kills rice production New York Times`8 (The New York Times, nationally syndicated magazine, Drought Connects Australian Crop Failure to Food Riots in Haiti A Drought in Australia, a Global Shortage of Rice, April 17, 2008 http://www.heatisonline.org/contentserver/objecthandlers/index.cfm?ID=6890&Method=Full)

Lindsay Renwick, the mayor of this dusty southern Australian town, remembers the constant whir of the rice mill. "It was our little heartbeat out there, tickety-tick-tickety," he said, imitating the giant fans that dried the rice, "and now it has stopped." The Deniliquin mill, the largest rice mill in the Southern Hemisphere, once processed enough grain to meet the needs of 20 million people around the world. But six long years of drought have taken a toll, reducing Australia's rice crop by 98 percent and leading to the mothballing of the mill last December. Ten thousand miles separate the mill's hushed rows of oversized silos and sheds -- beige, gray and now empty -from the riotous streets of Port-au-Prince, Haiti, but a widening global crisis unites them. The collapse of Australia's rice production is one of several factors contributing to a doubling of rice prices in the last three months µ increases that have led the worlds largest exporters to restrict exports severely, spurred panicked hoarding in Hong Kong and the Philippines, and set off violent protests in countries including Cameroon, Egypt, Ethiopia, Haiti, Indonesia, Italy, Ivory Coast, Mauritania, the Philippines, Thailand, Uzbekistan and Yemen. Drought affects every agricultural industry based here, not just rice µ from sheepherding, the other mainstay in this dusty land, to the cultivation of wine grapes, the fastest-growing crop here, with that expansion often coming at the expense of rice. The droughts effect on rice has produced the greatest impact on the rest of the world, so far. It is one factor contributing to skyrocketing prices, and many scientists believe it is among the earliest signs that a warming planet is starting to affect food production. It is difficult to definitely link short-term changes in weather to long-term climate change, but the unusually severe drought is consistent with what climatologists predict will be a problem of increasing frequency. Indeed, the chief executive of the National Farmers Federation in Australia, Ben Fargher, says, Climate change is potentially the biggest risk to Australian agriculture. Drought has already spurred significant changes in Australias agricultural heartland. Some farmers are abandoning rice, which requires large amounts of water, to plant less water-intensive crops like wheat or, especially here in southeastern Australia, wine grapes. Other rice farmers have sold fields or water rights, usually to grape growers.

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Dimming Good-Solves Warming-Solves Corn [1/2] Rising temperatures hurt corn yields Storm wire`8 (Stom wire, news agency dedicated to climates impact on business Monday, June 16, 2008 Global Warming Could Impact U.S. Crop Production, http://stormwire.stormexchange.com/2008/06/global-warming-could-impact-us-crop.html)

The U.S. Department of Agriculture reports that global warming will have both a positive and negative effect on crop yields across the country. Warmer temperatures in the coming decades would reportedly have an adverse impact on corn yields, but increase yields for crops like soybeans. As we’ve seen this spring, corn yield fluctuates from year-to-year, but has likely fared better in the last eight years because of new seeds and fertilizers aimed at maximizing growth. Warmer temperatures brought on by greenhouse gas emissions may cause drought-like conditions and weaken plants like corn. U.S.D.A. scientists report that the output of corn crops grown today could fall as much as 5 percent in coming decades. The report synthesized peer-reviewed studies on how climate change would affect agriculture, most of which assumed U.S. temperatures would rise about 1.2 degrees Celsius (2.2 degrees Fahrenheit) over the next 30 to 50 years, as indicated by the U.N.'s Intergovernmental Panel on Climate Change report last year, according to Reuters. "We're running into a situation in which we have the greater likelihood of occurrences of extreme temperature events during critical growth stages of that crop," Jerry Hatfield, the lead author of the agriculture section of the report, said about corn in a teleconference. Corn is the top U.S. crop and is the main feedstock for the country's ethanol industry. Soybeans rank second, with soyoil used to make biodiesel. Hatfield said many crops like corn are already grown near the highest temperatures they can stand, which makes them vulnerable to warmer weather. Other crops, like soybeans, can withstand higher temperatures, which means higher temperatures may increase their yield, he said. The report did not project how yields would change should growers switch to corn varieties that could be more drought or temperature resistant.

Hot dry weather hurts US corn crops Planet ark`5 (Planet Ark, website dedicated to saving environment, Hot, Dry Weather Wilts US Corn Crop – US Department of Agriculture, July 13, 2005 http://www.planetark.com/dailynewsstory.cfm/newsid/31631/story.htm)

Hot, dry weather in Illinois, Indiana and Ohio will cut the US corn harvest by at least 1 billion bushels -- a massive 8.6 percent -- from last year's record, the government said Tuesday. However, the nation's wheat and cotton crops were flourishing for the most part, the Agriculture Department said in an update of US and global farm production. Soybeans were under pressure but not suffering as much as corn. The USDA projected a US corn crop of 10.785 billion bushels, down 200 million bushels, or 1.8 percent, from last month despite the largest plantings since 1985. That would be far below the record 11.807 billion bushels of 2004. Wheat growers were forecast to reap a larger-than-expected 2.208 billion bushels this year, up 89 million bushels from the USDA's June estimate. The government projected a US cotton crop of 19.80 million bales, up 300,000 bales from June. Soybeans were down slightly at 2.89 billion bushels. Half of the corn in Illinois, usually the nation's No. 2 corn state, was in poor or very poor condition as of Sunday. In Indiana, 27 percent of corn was in those two categories and in Ohio, 16 percent was poor or very poor. "The crop is crying for rain," said private consultant John Schnittker. Some rainfall was expected this week, blown into the eastern Corn Belt by Hurricane Dennis. Corn is the most widely grown US crop, planted on 81.6 million acres (33 million hectares). It is a base ingredient in livestock rations and increasingly used in making motor fuel, aside from food and other industrial uses. Deputy Agriculture Secretary Chuck Conner said soybeans in the eastern Corn Belt during a recent trip were "much smaller than usual." But he added, "I didn't see anything that good rain from Dennis wouldn't benefit." The storms may also carry spores of yield-cutting soybean rust fungus already found in Florida, Georgia and Alabama. That threat was "something to keep your eyes on the next couple of days," Conner told reporters. CORN FUTURES CHOPPY ON WEATHER UNCERTAINTY At the trendsetting Chicago Board of Trade, futures prices for corn were up slightly at the end of the day, supported by concerns that remnants of Hurricane Dennis would bring less rain than initially thought to the parched eastern Midwest. Corn for July delivery was up 1/4 cent, to $2.27 a bushel. December corn was also up 1/4 cent at $2.47. November soybeans were up 11 cents, to $7.12-1/2 a bushel on prospects of smaller South American

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Dimming Good-Solves Warming-Solves Corn [2/2] crops and a drop from last year's record US crop. July wheat was down 3-1/4 cents, to $3.23-3/4 a bushel. In assessing the corn crop, USDA said yields would average 145 bushels an acre this year, compared with 160.4 bushels an acre for the 2004 crop, which enjoyed nearly ideal weather. Across the Mississippi River, corn was in dramatically better shape. Three-fourths of the crop in Iowa, Minnesota and Nebraska was rated as good or excellent. Globally, the USDA cut its monthly estimate of corn stocks for 2005/06 by nearly 7 million tonnes to reflect smaller crops in the United States and elsewhere. The worldwide stockpile of corn at the end of 2005/06 is now seen at 114 million tonnes, down from nearly 126 million tonnes in 2004/05. Soybean fields west of the Mississippi River were in better condition than those to the east, USDA ratings showed. Overall, soybeans are in better shape than corn, now in a critical reproductive stage. Soybeans mature in August and tolerate drought better. The USDA raised its US wheat forecast because of record-high winter wheat yields in South Dakota and Montana and "much better than previously expected" yields for soft red winter wheat. It also said durum and spring wheat crops would be 4 percent larger than last year. However, lower yields are now forecast for part of the Great Plains because dry spring conditions had more of an impact than previously thought, it said. Colorado, Kansas, Oklahoma and Texas were down by a total 46.5 million bushels , it said.

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Dimming Good - Soil Moisture Solar dimming key to soil moisture Robock & Li`6 (A. Robock and H. Li Department of Environmental Sciences, Rutgers University, New Brunswick, New Jersey, USA, Effects of solar dimming on soil moisture trends, 2006, http://209.85.141.104/search?q=cache:LX2dQUtKgOoJ:www.cosis.net/abstracts/EGU06/08331/EGU06-J-08331.pdf)

Soil moisture variations depend principally on variations of the two main surface forcings, precipitation and solar radiation. While much attention in the past has been paid to precipitation variations, only recently have solar radiation data sets allowed analysis of their effects. Using the longest soil moisture data set in the world, 47 yr of April-October in situ observations for the Ukraine, 1958-2004, we previously noted that an upward trend in summer soil moisture for the first half of the period cannot be explained simply by precipitation trends for the region. Recent observations of solar insolation in the region have discovered a phenomenon labeled “solar dimming,” a downward trend in incoming solar radiation due to the effects of tropospheric aerosol pollution on direct solar radiation and indirectly on cloud properties. The observed time series of solar radiation is a mirror image of the soil moisture curve, and also matches an observed downward trend in pan evaporation. To investigate how strong this effect may be on soil moisture, we conducted off-line simulations with the Noah land surface model over the domain, 22-40E, 46-52N. A control run using a standard forcing data set, which did not explicitly include solar dimming effects due to aerosols, did not produce the observed trends. We then modified the standard forcing by imposing downward trends on the incoming solar radiation for the first half of the period to simulate solar dimming. The results produce an improved simulation of the observed soil moisture trends and serve to quantify the effects of solar radiation trends on land surface hydrology.

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Soil Moisture Impact - Drought Dimming solves drought-Increasing soil moisture World Climate Report`6 (World Climate Report, Dimming Fights Drought?, November 27, 2006, http://www.worldclimatereport.com/index.php/2006/11/27/dimming-fights-drought/)

A recent article in Geophysical Research Letters by Rutgers’ scientists Alan Robock and Haibin Li addresses the issue of global warming and reduced soil moisture levels in important agricultural areas. Every popular global warming presentation lays out the case that higher temperatures in the future will cause higher levels of evaporation that will overwhelm any changes in precipitation and force soil moisture levels to drop. Of course, crops will fail, we will have more frequent and severe droughts of longer duration, and it will have all been caused by elevated carbon dioxide (CO2) levels. You’ve heard the story a 1,000 times by now. Robock and Li note “Potential soil moisture changes from global warming, especially desiccation in growing seasons, are a grave threat to food security on which human society relies. Numerical models have been utilized to explore how water storage will change with global warming. Many models predict a decline of soil moisture over the midlatitudes of the Northern Hemisphere.” But it was the first sentence of their abstract that grabbed our attention at World Climate Report as they drop the bomb “Summer soil moisture increased significantly from 1958 to the mid 1990s in Ukraine and Russia. This trend cannot be explained by changes in precipitation and temperature alone.” Oh no, just where the soil moisture should be drying up due to global warming, we find that soil moisture levels are going up. They write “The reported upward summer soil moisture trends for many Former Soviet Union stations are consistent with the decrease of pan evaporation around the same period for the same region, as pan evaporation can be thought as a direct measurement of the atmospheric evaporative demand.” (This work is a follow-on to an earlier examination of soil moisture trends in the Ukraine conducted by Robock and colleagues a few year ago, see here for our take on that one). So what is causing soil moisture to increase? How about solar dimming and upward CO2 concentrations? Robock and Li note “Both ground-based observations and satellite measurements reveal a widespread reduction of solar irradiance from 1950s to 1990s and a gradual recovery afterwards, known as the ‘global dimming’ phenomenon. Increasing atmospheric aerosol loading from rapid industrialization is believed to be the culprit.” The argument is that global dimming has reduced solar radiation and “In the context of the hydrological cycle, the reported decline of shortwave radiation over such a long period may potentially increase water storage over land by damping evaporative demand from the atmosphere.” There’s even more, and it just gets better and better! Robock and Li recall that “Many plant species tend to reduce stomatal openings with increasing atmospheric CO2. The concurrent higher canopy resistance reduces water loss through plant transpiration and thus may have profound impacts on the hydrological cycle” and that “A recent study suggests such CO2 effects are to a large extent responsible for continental runoff increases for the 20th century.” To investigate the role of dimming and CO2 fertilization on soil moisture trends, Robock and Li “conducted experiments with a sophisticated land surface model.” The figure below shows the simulated and observed soil moisture in summer. The team wrote “The observed soil moisture for Ukraine exhibits an increase from 1958 to the early 1980s and then starts to level off afterwards. So does the soil moisture in the control but with much smaller magnitude. Imposed dimming brings additional soil moisture increase compared to the control. The stronger the dimming, the higher the increase in soil moisture” (Figure 1). And in terms of the effect of CO2, they found “The elevated CO2 caused very small soil moisture increases in contrast with the constant CO2 scenario. This is no surprise since in the elevated CO2 cases, evapotranspiration decreased by only about 0.1%.”

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Soil Moisture Impact - Biodiversity Soil Moisture key to sustainability of ecosystems and plants IPCC`1(Intergovernmental Panel on Climate Change, The IPCC is a scientific intergovernmental body set up by the World Meteorological Organization (WMO) and by the United Nations Environment Programme (UNEP)., Precipitation, Soil Moisture, and River Flow: Elements of the Hydrological Cycle, http://www.grida.no/climate/ipcc_tar/wg1/512.htm)

Changes in precipitation could have significant impacts on society. Precipitation is an essential element in determining the availability of drinking water and the level of soil moisture. Improved treatment of precipitation (see Chapter 7, Section 7.2.3) is an essential step. Soil moisture is a key component in the land surface schemes in climate models, since it is closely related to evapotranspiration and thus to the apportioning of sensible and latent heat fluxes. It is primary in the formation of runoff and hence river-flow. Further, soil moisture is an important determinant of ecosystem structure and therein a primary means by which climate regulates (and is partially regulated by) ecosystem distribution. Soil moisture is an important regulator of plant productivity and sustainability of natural ecosystems. In turn terrestrial ecosystems recycle water vapour at the landsurface/atmosphere boundary, exchange numerous important trace gases with the atmosphere, and transfer water and biogeochemical compounds to river systems (see also the discussion in Chapter 7, Section 7.4.3 and Capter 8, Section 8.5.4). New efforts are needed in the development of models, which successfully represent the space-time dynamics interaction between soil, climate and vegetation. If water is a central controlling aspect, then the interaction necessarily passes all the way through the space-time dynamics of soil moisture. Finally, adequate soil moisture is an essential resource for human activity. Consequently, accurate prediction of soil moisture is crucial for simulation of the hydrological cycle, of soil and vegetation biochemistry, including the cycling of carbon and nutrients, and of ecosystem structure and distribution as well as climate. River systems are linked to regional and continental-scale hydrology through interactions among precipitation, evapotranspiration, soil water, and runoff in terrestrial ecosystems. River systems, and more generally the entire global water cycle, control the movement of constituents over vast distances, from the continental landmasses to the world’s oceans and to the atmosphere. Rivers are also central features of human settlement and development.

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Dimming Good-solves Forest Growth Dimming increases forest growth-The short decrease in total solar radiation increases diffuse radiation Lewis, Mahli, & Phillips`4 (Simon L. Lewis, Yadvinder Malhi, Oliver L. Phillips, Fingerprinting the Impacts of Global Change on Tropical Forest, The Royal Society, March 29, 2004, Jstor)

If satellite data showing an increase in incoming solar radiation are correct, then increases in forest growth are predicted, as shown in experiments (Graham et al. 2003). However, theory predicts two opposite outcomes for tropical forests in response to global dimming, if it is occurring (Stanhill & Cohen 2001). Firstly, a long-term reduction in solar radiation would decrease photosynthesis, and hence growth and stand biomass, if trees are light limited. Alternatively, the reduction in total solar radiation is likely to be accompanied by an increase in diffuse solar radiation (Stanhill & Cohen 2001). Theoretically, this is expected to increase total canopy photosynthesis, as diffuse light can penetrate deeper into a canopy by reducing the self-shading of leaves in the canopy (Roderick et al. 2001). This effect that plant canopies can use diffuse radiation more efficiently than direct radiation-has been demonstrated in a North American hardwood forest using measurements before and after the 1991 Mt Pinatubo volcanic eruption, which in 1992 decreased global direct solar irradiance by ca. 3% but increased diffuse irradiance by ca. 9% (Gu et al. 2003). Midday photosynthesis of the forest rose by 23% under cloudy conditions in 1992 compared with a control year. Thus, increasing the diffuse fraction of incoming solar radiation may cause large increases in forest growth.

Aerosols cause scatter radiation Ramanathan et al 2005 (V. Ramanathan, C. Chung, D. Kim, T. Bettge, L. Buja, J. T. Kiehl, W. M. Washington, Q. Fu, D. R. Sikka, M. Wild, Atmospheric Brown Clouds: Impacts on South Asian Climate and Hydrological Cycle, National Academy of Sciences, Apr. 12, 2005, Jstor)

Atmospheric brown clouds (ABCs) are basically layers of air pollution consisting of aerosols such as black carbon (BC), organic carbon, and dust that absorb and scatter solar radiation (1). ABCs also contain other anthropogenic aerosols such as sulfates, nitrates, and fly ash, which primarily scatter solar radiation. The absorption of solar radiation by ABCs contributes to atmospheric solar heating. The absorption together with the scattering leads to a large reduction of UV and visible wave- length solar radiation at the surface (2), alternately referred to as dimming (3). In addition, aerosols nucleate more cloud drops that enhance scattering of solar radiation and contribute to additional dimming (4). The nucleation of clouds by aerosols also reduces the precipitation efficiency of clouds (5). The ABC radiative forcing can reduce rainfall through several mechanisms as described below.

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Dimming Good- ⇓ Sea Temps Aerosols decrease surface sea temperatures, and solve climatic stability Ramanathan et al 2005 (V. Ramanathan, C. Chung, D. Kim, T. Bettge, L. Buja, J. T. Kiehl, W. M. Washington, Q. Fu, D. R. Sikka, M. Wild, Atmospheric Brown Clouds: Impacts on South Asian Climate and Hydrological Cycle, National Academy of Sciences, Apr. 12, 2005, Jstor)

South Asian emissions of fossil fuel S02 and black carbon increased -6-fold since 1930, resulting in large atmospheric concentrations of black carbon and other aerosols. This period also witnessed strong negative trends of surface solar radiation, surface evaporation, and summer monsoon rainfall. These changes over India were accompanied by an increase in atmospheric stability and a decrease in sea surface temperature gradients in the Northern Indian Ocean. We conducted an ensemble of coupled ocean- atmosphere simulations from 1930 to 2000 to understand the role of atmospheric brown clouds in the observed trends. The simulations adopt the aerosol radiative forcing from the Indian Ocean experiment observations and also account for global increases in greenhouse gases and sulfate aerosols. The simulated decreases in surface solar radiation, changes in surface and atmospheric temperatures over land and sea, and decreases in monsoon rainfall are similar to the observed trends. We also show that greenhouse gases and sulfates, by themselves, do not account for the magnitude or even the sign in many instances, of the observed trends. Thus, our simulations suggest that absorbing aerosols in atmospheric brown clouds may have played a major role in the observed regional climate and hydrological cycle changes and have masked as much as 50% of the surface warming due to the global increase in greenhouse gases. The simulations also raise the possibility that, if current trends in emissions continue, the subcontinent may experience a doubling of the drought frequency in the coming decades.

Global dimming cools oceans Ramanthan`7 ( V.,

Scripps Institution of Oceanography, University of California at San Diego, CA, USA, Nucleation and Atmospheric Aerosols, SpringerLink DateThursday, November 15, 2007, http://www.springerlink.com/content/r12q211506213824/)

The global build up of greenhouse gases (GHGs), is the most vexing global environmental issue facing the planet. GHGs warm the surface and the atmosphere with significant implications for, rainfall, retreat of glaciers and sea ice, sea level, among other factors. What is less recognized, however, is a comparably major global problem dealing with air pollution. Until about 10 years ago, air pollution was thought to be just an urban or a local problem. But new data have revealed that, due to fast long-range transport, air pollution is transported across continents and ocean basins, resulting in transoceanic and transcontinental plumes of atmospheric brown clouds (ABCs) containing submicronsize particles, i.e., aerosols. ABCs intercept sunlight by absorbing as well as reflecting it, both of which lead to a large surface dimming. The dimming effect is enhanced further because aerosols nucleate more cloud drops which makes the clouds reflect more solar radiation. The surface cooling from this dimming effect has masked the warming due to GHGs. ABCs are concentrated in regional and megacity hot spots. Long-range transport from these hot spots gives rise to widespread plumes over the adjacent oceans. Such a pattern of regionally concentrated surface dimming and atmospheric solar heating, accompanied by widespread dimming over the oceans, gives rise to large regional effects. Only during the last decade, we have begun to comprehend the surprisingly large regional impacts. The large north–south gradient in the ABC dimming has altered the north–south gradients in sea surface temperatures, which in turn has been shown by models to decrease rainfall over the continents. In addition to their climate effects, ABCs lead to acidification of rain and also result in over few million fatalities worldwide. The surface cooling effect of ABCs may have masked as much 50% of the global warming. This presents a dilemma since efforts to curb air pollution may unmask the ABC cooling effect and enhance the surface warming. Thus efforts to curb GHGs and air pollution should be done under one framework. The uncertainties in our understanding of the ABC effects are large, but we are discovering new ways in which human activities are changing the climate and the environment. Keywords Global dimming, global warming

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Dimming Good-Solves Fish-Cold Waters Good Cooler waters are more conducive for fish-Migrations prove Sample`5 (Ian, The Guardian-Scientific specialist, North Sea fish on the move to cooler waters Shift due to climate change, say researchers, Friday May 13, 2005, http://www.guardian.co.uk/science/2005/may/13/environment)

Global warming has forced fish stocks in the North Sea scores of miles north to cooler waters, according to a study by climate change scientists. Major fish species, including cod and haddock, have sought out cooler waters in response to a 1C rise in the temperature of the North Sea over the past 25 years. In the same period, more exotic southern species have encroached on North Sea waters and established themselves. The shift in fish populations has profound implications for fisheries which have already driven stocks to record lows, the researchers say. Scientists at the University of East Anglia and researchers at the Centre for Environment Fisheries and Aquaculture Science in Lowestoft pored over fisheries data from 1977 to 2001 and looked at the relative abundance of catches. They also examined records of sea temperatures, general climatic patterns and the effects of the Gulf Stream. The researchers found that 21 species had shifted their distributions in line with the rise in sea temperature, and 18 species had moved much further north. According to the study, published today in the journal Science, the North Sea cod population has moved 73 miles towards the Arctic while haddock have moved 65 miles north. The study raises concerns that some already overexploited fish stocks are under further threat from climate change. Allison Perry, who co-authored the study, said: "We know these ecosystems are already under heavy pressure and this is an added stress. If we want to rebuild stocks we need to be more cautious because the conditions now aren't as suitable as they were 25 years ago." Professor John Reynolds, who led the study, said: "The fact that species such as haddock and cod have moved over 100km [63 miles] northward suggests that management programmes will need to be particularly precautionary if southerly populations are to recover from overfishing." Many of the species studied also moved to deeper waters as they shifted north, which may also have been driven by a search for cooler seas. Populations of six species, including plaice and cuckoo rays, moved to deeper waters without changing latitude. The findings demonstrate how sensitive fish stocks are to climate change. In 2003, scientists at the University of Texas reported that 99 species of birds, butterflies and alpine herbs had shifted 600 metres north each year because of global warming. In the latest study, fish populations headed north nearly four times as quickly, at an average of nearly 1.4 miles a year. The shifting populations of fish have implications beyond fisheries management. The study found that smaller fish with shorter lifecycles were more likely to move north in response to climate change, with larger, slower-growing fish lagging behind. Scientists now fear that differing abili ties to respond to warming waters will fragment ecosystems by separating predators from their usual prey. Ms Perry said scientists were not sure whether those species that are not moving north are simply more resilient to climate change. "It might be that they aren't able to move further north because they have certain habitat requirements we're unaware of that are limited further to the north," she said.

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Dimming Good-Solves Coral Bleaching Cooling key to save coral AGU`8 (AGU, Science and Society, Peter Weiss, Natural ocean thermostat may protect some coral reefs, 7 February 2008 http://www.agu.org/sci_soc/prrl/2008-05.html)

Coral reefs face a multitude of threats, including overfishing, coastal development, pollution, and changes to ocean chemistry caused by rising levels of carbon dioxide in the atmosphere. But global warming presents a particularly grave threat because unusually warm ocean temperatures can lead to episodes of coral bleaching, in which corals turn white after expelling the colorful microscopic algae that provide them with nutrition. Unless cooler temperatures return in a few days or weeks, allowing algae to grow again, bleached corals often collapse and die. Bleaching can occur naturally, but it has become increasingly widespread in recent decades. This is largely because sea-surface temperatures in tropical waters where corals live have increased about 0.50.7 degrees Fahrenheit (0.3-0.4 degrees Celsius) over the last two to three decades, with temperatures occasionally spiking higher. However, between 1980 and 2005, only four episodes of bleaching have been reported for reefs in the Western Pacific Warm Pool. This is a lower rate than any other reef region, even though the western Pacific reefs appear to be especially sensitive to temperature changes. Sea-surface temperatures in the warm pool naturally average about 85 degrees Fahrenheit (29 degrees Celsius), which is close to the proposed thermostat limit. They have warmed up by about half as much as in cooler areas of the oceans.

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Dimming Good-Dimming Solves Plankton [1/2] SO2 increases plankton growth ScienceDaily`5 http://www.sciencedaily.com/releases/2005/02/050213130304.htm, 02/05 surprising link may exist between ocean fertility and air pollution over land, according to Georgia Institute of Technology research reported in the Feb. 16 issue of the Journal of Geophysical Research — Atmospheres. The work provides new insight into the role that ocean fertility plays in the complex cycle involving carbon dioxide and other greenhouse gases in global warming. When dust storms pass over industrialized areas, they can pick up sulfur dioxide, an acidic trace gas emitted from industrial facilities and power plants. As the dust storms move out over the ocean, the sulfur dioxide they carry lowers the pH (a measure of acidity and alkalinity) level of dust and transforms iron into a soluble form, said Nicholas Meskhidze, a postdoctoral fellow in Professor Athanasios Nenes' group at Georgia Tech's School of Earth and Atmospheric Sciences and lead author of the paper "Dust and Pollution: A Recipe for Enhanced Ocean Fertilization." This conversion is important because dissolved iron is a necessary micronutrient for phytoplankton — tiny aquatic plants that serve as food for fish and other marine organisms, and also reduce carbon dioxide levels in Earth's atmosphere via photosynthesis. Phytoplankton carry out almost half of Earth's photosynthesis even though they represent less than 1 percent of the planet's biomass. In research funded by the National Science Foundation, Meskhidze began studying dust storms three years ago under the guidance of William Chameides, Regents' Professor and Smithgall Chair at Georgia Tech's School of Earth and Atmospheric Sciences and co-author of the paper. "I knew that large storms from the Gobi deserts in northern China and Mongolia could carry iron from the soil to remote regions of the northern Pacific Ocean, facilitating photosynthesis and carbon-dioxide uptake," Meskhidze said. "But I was puzzled because the iron in desert dust is primarily hematite, a mineral that is insoluble in high-pH solutions such as seawater. So it's not readily available to the plankton." Using data obtained in a flight over the study area, Meskhidze analyzed the chemistry of a dust storm that originated in the Gobi desert and passed over Shanghai before moving onto the northern Pacific Ocean. His discovery: When a high-concentration of sulfur dioxide mixed with the desert dust, it acidified the dust to a pH below 2 — the level needed for mineral iron to convert into a dissolved form that would be available to phytoplankton. Expanding on this discovery, Meskhidze studied how variations in air pollution and mineral dust affect iron mobilization. Obtaining in-flight data from two different Gobi-desert storms — one occurring on March 12, 2001, and the other on April 6, 2001 -Meskhidze analyzed the pollution content and then modeled the storms' trajectory and chemical transformation over the North Pacific Ocean. Using satellite measurements, he determined whether there had been increased growth of phytoplankton in the ocean area where the storms passed. The results were surprising, he said. Although the April storm was a large one, with three sources of dust colliding and traveling as far as the continental United States, there was no increased phytoplankton activity. Yet the March storm, albeit smaller, significantly boosted the production of phytoplankton. The differing results can be attributed to the concentration of sulfur dioxide existing in dust storms, Meskhidze said. Large storms are highly alkaline because they contain a higher proportion of calcium carbonate. Thus, the amount of sulfur dioxide picked up from pollution is not enough to bring down the pH below 2. "Although large storms can export vast amounts of mineral dust to the open ocean, the amount of sulfur dioxide required to acidify these large plumes and generate bioavailable iron is about five to 10 times higher than the average springtime concentrations of this pollutant found in industrialized areas of China," Meskhidze explained. "Yet the percentage of soluble iron in small dust storms can be many orders of magnitude higher than large dust storms." So even though small storms are limited in the amount of dust they transport to the ocean and may not cause large plankton blooms, small storms still produce enough soluble iron to consistently feed phytoplankton and fertilize the ocean. This may be especially important for high-nitrate, low-chlorophyll waters, where phytoplankton production is limited because of a lack of iron. Natural sources of sulfur dioxide, such as volcanic emissions and ocean production, may also cause iron mobilization and stimulate phytoplankton growth. Yet emissions from human-made sources normally represent a larger portion of the trace gas. Also, human-made emission sites may be closer to the storm's course and have a stronger influence on it than natural sulfur dioxide, Meskhidze said. This research deepens scientists' understanding of the carbon cycle and climate change, he added. "It appears that the recipe of adding pollution to mineral dust from East Asia may actually enhance ocean productivity and, in so doing, draw down atmospheric carbon dioxide and reduce global warming," Chameides said. "Thus, China's current plans to reduce sulfur dioxide emissions, which will have far-reaching benefits for the environment and health of the people of China, may have the unintended consequence of exacerbating global warming," he added. "This is perhaps one more reason why we all need to get serious about reducing our emissions of carbon dioxide and other greenhouse gases."

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Dimming Good-Dimming Solves Plankton [2/2] Cool water is better for plankton-They produce a sulfur compound themselves that cause dimming and water cooling Monastersky`87 (Richard, The Plankton-Climate Connection, Society for Science and the public, Dec. 5, 1987, Jstor) The chemical link between plankton and clouds is a sulfur compound called dimethylsulfide (DMS). Inside the plankton cells, DMS protects against the high salt concentrations of the outside seawater. The cells excrete DMS as a normal metabolic product, but the compound also enters seawater when plankton are eaten or die. DMS then diffuses from the seawater into the atmosphere. For decades, says Gaia author Love lock, this was the extent of the scientific knowledge about DMS. Nobody really questioned the subsequent fate of the compound. "They thought it was just a biochemical curiosity," he says. But in the 1970s, research into the Gaia hypothesis prompted Lovelock to examine the world's sulfur budget in detail, which meant keeping close track of all the important forms of sulfur. And this continued interest in DMS helped reveal its climatic role. While Lovelock was musing on the fate of DMS, Robert Charlson of the University of Washington in Seattle was working independently at the other end of the problem. As an atmospheric scientist, Charlson had been wondering how marine clouds grow. Clouds are actually composed of particles of water. But before they can develop, there must be some sort of nuclei onto which water can condense. Says Lovelock, "It was a speculation by Bob Charlson: Where did the cloudcondensation nuclei come from? We talked about DMS, and it seemed natural that it could be the source." Earlier this year, in the April 16 NATURE, Lovelock, Charlson and their colleagues proposed that once DMS reaches the atmosphere, it oxidizes to form sulfate particles, which then serve as condensation nuclei for developing cloud particles. Scientists widely believed- though they had not proved it at the time of the paper - that the number of cloud particles determines the reflective properties of clouds. An increase in the number of condensation nuclei was thought to make marine stratus clouds reflect more sunlight. These types of clouds cover 30 percent of the world at any time, says Charlson, so an increase in their reflectivity would cut off much of the radiation that reaches the ocean surface, thereby lowering the water's surface temperature. According to the theory, if plankton produced more DMS, the surface of the earth would get cooler. Within the last several months, new evidence has confirmed the major links in this plankton- climate chain. Charlson, with Timothy S. Bates and Richard H. Gammon of the Pacific Marine Environmental Laboratory in Seattle, reported in the Sept. 24 NATURE that they found a direct correlation between DMS levels and the numbers of cloud nuclei in portions of the Pacific. These researchers found that the number of nuclei in the area they studied varies with both season and latitude, and that a markedly similar relationship ap- plies to the DMS concentrations in the seawater. This supports the theoretical prediction that DMS is providing the particles that serve as the condensation nuclei for marine stratus clouds. The next step in the planktonclimate theory linked the number of con- densation nuclei to the reflectivity of clouds. Scientists have understood this theoretical relationship for years. If a cloud has a certain amount of water and the number of available nuclei increases, explains Bates, "it means that the given water vapor is spread out more, and you have more surface area to reflect incoming solar radiation." But that relationship had gone un- tested until this year, when James A. Coakley and his colleagues noticed that the exhaust from ships left long, highly reflective trails in marine clouds - an |CLOUDS TEMR CLOUD CONDENSATION NUCLEI ? DMS| PLANKTON| |

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Dimming Good-Solves Sea Levels Empirically dimming holds down sea levels Property Investing`6 (Property Investing.net, Global warming - analysis, insights and property 11-252006http://www.propertyinvesting.net/cgi-script/csNews/csNews.cgi?database=specialreports.db104&command=viewonex#)

What Happened 1981 to 2006: The collapse of the Soviet Empire culminating in the Berlin Wall falling and the end of the Cold War – this lead to a massive reduction in dirty brown coal usage in Russia and the old Eastern European states. Brown coal power stations were closed and steel works and heavy industry died. This resulted in a sudden and massive drop in dimming. More overall global energy usage led to increases in carbon dioxide which compounded with the cleaner air to cause a sudden increase in global temperatures from 1981 onwards. The increased use of airlines helped reduce this effect by putting more ice trails into the sky, but this was not enough to stop warming. As smog levels and particulate pollution reduced, this exacerbated the problem and lead to a rapidly rising temperatures on most parts of the world. This was particularly noticeable in Siberia, eastern Europe (less particulate pollution) and South America and Africa (deforestation). Increase usage of fossil fuels in India and China from 1990 onwards was not enough to counteract the cleaner air (less particulate pollution) in the global environment. The effects of the Mount Saint Helens eruption of 1980 wore off by 1982 and the sky’s became less dim. This accelerated by 1986 as the Berlin Wall came down and heavy industry was close. By the late 1990s, India also started to clean a lot of its power stations and environmental legislation in the USA and Europe in the 1990s lead to further cleaning and less dimming – exacerbating and increasing the global warming problem. Sea levels started to rise. Increasing airline usage (ice trails) was not nearly enough to dim the atmosphere are prevent further warming. 2001 Event: In the two days after 9/11 2001 when all US airplanes were grounded, the average temperature in the USA rose an unprecedented 0.5 degrees centigrade. The cause of this was lack of ice trails from the airline industry. This demonstrated beyond reasonable doubt that dimming caused by man-made mist in the earths atmosphere contributes to cooling and conversely, the lack of this causes warming.

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Dimming Good-Solves Wheat/Grain-Colder Temps Colder temperatures increase wheat production Singh`8 (Bajinder Pal, The Live mint.com associate fo the Wallstreet Journal, Lower temperatures help crop germination, besides extending the time the crop takes to mature, May 25, 2008, http://www.livemint.com/2008/05/25232333/Colder-andlonger-winter-boost.html?d=1)

In India, longer and colder winters usually mean nothing more than lazy mornings and respite from the impending heat. But there was more to it this time for wheat farmers in the country’s north-western region, with the production of wheat—the crop is normally harvested in April—showing a good rise compared with previous years. The bulk of this higher yield, which came from Punjab’s Malwa region, is due to a drop in temperatures in mid-December 2007 to mid-February and extended mild weather, experts say. Officials at the meteorological unit at the Punjab Agricultural University have confirmed this fall in temperature and continuation of mild weather till early April. First official estimates suggest the yield per hectare of wheat in the state this season was 4,450kg, almost 200kg more than what it was a year earlier. According to scientists at the wheat section of the Ludhiana-based Punjab Agricultural University, lower temperatures help crop germination, besides extending the time the crop takes to mature. Unlike in western Europe, where wheat takes around eight-nine months to ripen, in north-western India, it is ready for harvest in four-five months. Punjab’s deputy director of agriculture Gurdial Singh also confirmed that the colder and longer winter played a role in better wheat yields. Prolonged winter meant that the grain development was better and the grains were larger.

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Dimming Good-Solves Wheat-Warming Kills Wheat Hotter and drier temperatures are devastating wheat crops Time Magazine`7(Bryan Walsh, Global Warming's Next Victim: Wheat, Aug. 27, 2007, Time Magazine http://www.time.com/time/world/article/0,8599,1656570,00.html)

"The net result is that you'd have plants that develop faster and aren't able to accumulate mass," says David Lobell of the Lawrence Livermore National Laboratory. Lobell says global warming has already begun to take food off the world's table. According to a recent study he and his colleagues conducted, the temperature increase that occurred between 1981 and 2002 reduced major cereal crop yields by an annual average of 40 million metric tons — losses worth $5 billion a year. Those losses are sobering, but nothing compared to what might be in store: A recent study sponsored by the Consultative Group on International Agricultural Research forecast a 51% decline in India's wheat-growing land, potentially leaving hundreds of millions hungry. And, last week, China's top meteorological official warned that global warming could cut the nation's grain harvest by 5 to 10% by 2030. And all this will be happening while both countries add more mouths to feed. Even more important than temperature will the the impact of global warming on rainfall, both too much and too little. It's hard to predict how climate will change rainfall patterns, but the rule of thumb is that dry areas will get drier, wet areas will get wetter, and droughts and flooding will both become more common. The effects of prolonged drought can already be seen in Australia, where consistently dry weather ravaged last year's wheat crop, and threatens to do the same this year. Flooding can destroy entire fields in a single day, and over time can lead to soil erosion and loss, permanently crippling once fertile land. "Water shortages are going to be a major issue for food companies," says Bob Goldin, executive vice-president at the food-industry research firm Technomic. "It will have an impact on agriculture in terms of higher coasts and lower yield." The silver lining is that warming will make once-frigid northern latitudes more suitable for agriculture. But the new farmland won't make up for the loss of the old, because soils further north in territories such as Siberia or Labrador are thin in nutrients compared to the rich loam of tropical India. The best hope may instead lie in breeding drought and heat-resistant crop strains — which groups such as CIMMYT are already working on — and in tweaking agronomy techniques to conserve water and soil. But while that might be enough to preserve farming in a rich country like the U.S., very little is being done to prepare developing nations for the agricultural challenges of climate change. "It's the poor counties that will suffer the most," says Reynolds. That much, at least, won't change

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Dimming Good-Solving warming=More Warming [1/3] Solving global warming results in a net increase earth’s temperature Phil for humanity` No date (Phil B., posted on his website “Phil for humanity.org, Solving Global Warming Will Temporarily Cause Higher Temperatures, No date http://www.philforhumanity.com/Global_Dimming_Effects_on_Global_Warming.html)

Global warming is believed to be cause by other pollutions (mostly carbon dioxide and carbon monoxide) being released into the atmosphere. Therefore, all the pollution being released into the atmosphere is both increasing and decreasing the world’s average temperatures. Unfortunately, the effects of global warming and global dimming are NOT completely counteracting each other. The net effect is a continuous increase of the world’s average temperatures, thus global warming is increasing much faster than global dimming is cooling. This problem is even more complicated than it first appears. Since global warming is now starting to be seriously addressed, alternative sources of energy (that do not create pollution that causes global warming or global dimming) are being introduced throughout the world. When these pollutants start decreasing in the atmosphere, the pollutants that cause global dimming will decrease at a much faster rate than the pollutants that cause global warming, because global dimming pollutants are larger molecules that will most likely settle first and be more easily absorbed by plants and animals. In summary, when air pollution starts to decrease, the effects of global dimming will disappear more quickly. Thus, global cooling from global dimming will decrease first. Therefore, global warming will have less counter-acting global cooling from global dimming, so the planet’s temperatures will increase even more in the short term. How short, no one knows.

Reducing particles will increase global temperature within days BBC`6 (Brittish Broadcasting Corporation, Transcript of the documentary “Global Dimming” http://www.informationclearinghouse.info/article15809.htm)

NARRATOR: If so much could happen in such a short time, removing just one form of pollution, then it suggests that the overall effect of Global Dimming on world temperatures could be huge. DR DAVID TRAVIS: The nine eleven study showed that if you remove a contributor to Global Dimming, jet contrails, just for a three day period, we see an immediate response of the surface of temperature. Do the same thing globally we might see a large scale increase in global warming. NARRATOR: This is the real sting in the tail. Solve the problem of Global Dimming and the world could get considerably hotter. And this is not just theory, it may already be happening. In Western Europe the steps we have taken to cut air pollution have started to bear fruit in a noticeable improvement in air quality and even a slight reduction in Global Dimming over the last few years. Yet at the same time, after decades in which they held steady, European temperatures have started rapidly to rise culminating in the savage summer of 2003. Forest fires devastated Portugal. Glaciers melted in the Alps. And in France people died by the thousand. Could this be the penalty of reducing Global Dimming without tackling the root cause of global warming? DR BEATE LIEPERT: We thought we live in a global warming world, um but this is actually er not right. We lived in a global warming plus a Global Dimming world, and now we are taking out Global Dimming. So we end up with the global warming world, which will be much worse than we thought it will be, much hotter. NARRATOR: This is the crux of the problem. While the greenhouse effect has been warming the planet, it now seems Global Dimming has been cooling it down. So the warming caused by carbon dioxide has been hidden from us by the cooling from air pollution. But that situation is now starting to change. DR PETER COX (Hadley Centre, Met Office): We're gonna be in a situation unless we act where the cooling pollutant is dropping off while the warming pollutant is going up, CO2 will be going up and particles will be dropping off and that means we'll get an accelerated warming. We'll get a double whammy, we'll get, we'll get reducing cooling and increased heating at the same time and that's, that's a problem for us.

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Dimming Good-Solving warming=More Warming [2/3] Cutting the burning of fossil fuels speeds up global warming and makes it worst ABC News`5 (America’s Broadcasting Corporation, Fossil fuel cuts may warm up Earth, January 13, 2005. http://www.abc.net.au/news/newsitems/200501/s1281460.htm)

Cutting down on fossil fuel pollution could accelerate global warming and help turn parts of Europe into desert by 2100, according to research to be aired on British television. A BBC Horizon documentary, Global Dimming, will describe research suggesting fossil fuel by-products like sulphur dioxide particles reflect the sun's rays, "dimming" temperatures and almost cancelling out the greenhouse effect. The researchers say cutting down on the burning of coal and oil, one of the main goals of international environmental agreements, will drastically heat rather than cool the climate. "When the cooling affect goes away - and it must do because particles like sulphur dioxide are damaging to humans - global warming will be much stronger," climate change scientist Dr Peter Cox said. The researchers say that temperatures could increase in the worst case by up to 10 degrees by the end of the century - much more than current estimates. Scientists differ as to whether global warming is caused by manmade emissions of carbon dioxide and other "greenhouse" gases, by natural climate cycles or if it exists at all. Dr Cox says take away fossil fuel by-products like sulphur dioxide without tackling greenhouse gas emissions, and the extra heat will speed warming. That will irreversibly melt ice sheets and rendering rainforests unsustainable within decades. "The climate will warm more in the future but the ability of the land to store carbon dioxide will be compromised," Dr Cox said. He says warmer soil is less able to hold the greenhouse gas.

An end in fossil fuel use substantially increases global temperature-It should be enough to set off their impacts Earth & Sky` No date (Earth

& Sky, environmental radio station, transcript of “What if we stopped burning fossil fuels today, http://www.earthsky.org/radioshows/45075/what-if-we-stopped-burning-fossil-fuels-today)

DB: This is Earth and Sky. When we burn fossil fuels, we release greenhouse gases. Most climate scientists agree that these gases are helping make our planet warmer. JB: Now imagine we could stop burning fossil fuels, today. What would happen to Earth’s climate? Tom Wigley is a senior scientist at the National Center for Atmospheric Research in Boulder. He uses a computer model that factors in many of the byproducts of fossil fuel burning – including sulfur dioxide, carbon dioxide, nitrous oxide, aerosols, ozone and methane. DB: If we stopped burning fossil fuels today, he said global warming would speed up, at first. That’s because sulfur dioxide cools Earth. Wigley’s model shows a temporary warming of as much as one degree Fahrenheit – or half a degree Celsius. But sulfur dioxide breaks down quickly. After it disappeared, about 20 years from now, Earth would gradually start cooling back down. It would return to current temperatures in about 200 years, by about the year 2200. Here’s Tom Wigley.

Less pollution risk exacerbating global warming Pincock`7 (Stephen, The Finnancial Times of London, Fluffy thinking The role of clouds in global warming is not fully understood. Sometimes they can trap heat; at other times they have a cooling effect is reflecting radiation back into space, February 3, 2007 Saturday, Lexis)

The difficulty with clouds is that they can interact with the sun's rays in different ways, depending on their composition. In some situations, clouds can act like a blanket to trap heat from the Earth; in others, they can have a cooling effect by reflecting radiation from the sun back into space. Researchers have been investigating the way clouds are involved in the greenhouse effect for a couple of decades or so, developing ever more sophisticated explanations for how they are formed and how they behave. They have gone far beyond cirrus, cumulus and nimbus, but it would be fair to say that there are still difficult questions to answer. In models of climate change, for example, the behaviour of clouds and aerosols in the atmosphere are responsible for much uncertainty. In June last year, climate researcher Daniel Rosenfeld from the Hebrew University of Jerusalem

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Dimming Good-Solving warming=More Warming [3/3] pointed out one of those question marks in an article in Science magazine. Rosenfeld explained that some pollution aerosols can act as "cloud condensation nuclei", acting as seeds around which clouds form. Those clouds tend to contain a greater number of small water drops, which are slower to merge and fall as rain. The result is that those clouds are thicker, bigger and hang around longer, thus reflecting more sunlight back into space and partially mitigating global warming. "These aerosol effects are poorly quantified and represent the greatest uncertainty in our understanding of the climate system," Rosenfeld wrote. One risk is that the effect of these aerosols might have had a temporary damping effect on global warming that will evaporate as we pollute less.

Cleaning up pollution causes more warming Harvey`7 (Fiona, London Finnancial Times, The world on the edge Scientists are certain that our climate is changing. The challenge now is to tell us what could tip us into catastrophe - and when, April 28, 2007, Lexis)

Global dimming Although we are on course to double the amount of carbon dioxide that was present in the atmosphere in preindustrial times, another form of pollution may be saving us from the worst effects. Particles in the atmosphere come from natural sources such as volcanoes, desert dust and forest fires, but also from fossil fuel combustion. Burning coal, for instance, produces sulphur as well as carbon particles. These particles may be reflecting some of the sun's radiance back into space. The effect of this is to counteract global warming, earning the phenomenon the name "global dimming". It is difficult to tell how much this effect, caused by industrialisation and changing land use, which creates dust, is diminishing the heating effect of greenhouse gases. Estimates suggest it could account for as much as a 4 per cent reduction in the sun's heat reaching the earth since the 1950s, although moves to clear up pollution in the past two decades could have lessened this. Paradoxically, then, cleaning up air pollution could leave us open to more global warming. This has led some experts to suggest we spray particles, such as sulphur, into the air as a way of cooling the earth.

Policies designed to reduce warming reduce aerosols increasing temperatures Cox`6 (Tayler, Deputy editor of the Stanford Review, Global Dimming: A New Perspective on Climate Change May 12, 2006 http://www.stanfordreview.org/Archive/Volume_XXXVI/Issue_8/Opinions/opinions1.shtml)

While global temperatures show an upward trend since 1860, dimming and cooling started to outweigh the effects of global warming in the late 1940’s. Then starting in 1970 with the Clean Air Act in the United States and similar policies in Europe, atmospheric sulfate aerosols declined significantly. The EPA reports that in the U.S. alone from 1970 to 2005, total emissions of the six principal air pollutants, including PM’s, dropped by 53 percent. In 1975, the masked effects of trapped greenhouse gases finally started to emerge and have dominated ever since. While a few dissenters hold on to alternate theories of natural variance or solar influence on climate change, the official report by the Intergovernmental Panel for Climate Control (IPCC) in 2001 attributed global warming to human greenhouse gas emission, and predicted rises up to 5.8° C in temperature by 2100. Similarly, according to data collected by the National Oceanic and Atmospheric Administration (NOAA) Paleoclimatology Program from Antarctic ice cores in 2004, global temperature over the last 740,000 years correlate significantly with greenhouse gas levels in the atmosphere. The continued success of global aerosol clean-up since the 90’s may have contributed to a rise in sunlight reaching the earth over the last decade, and hint that global warming may now increase faster and at even greater magnitudes than we previously thought. Some scientists recently revised their predictions of climate change to an increase in 10° C by the year 2100. This could transform large tracts of continents to inhospitable deserts.

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Dimming Good-Solves Disease Mosquitoes need a warm and wet climate to breed and transmit disease CDC`4 (Center for Disease Control, Federal Disease headquarters, Malaria, April 30, 2004, http://www.cdc.gov/malaria/distribution_epi/epidemiology.htm)

Climate can influence all three components of the life cycle. It is thus a key determinant in the geographic distribution and the seasonality of malaria. Rainfall can create collections of water ("breeding sites") where Anopheles eggs are deposited, and larvae and pupae develop into adulthood, a process that takes approximately 9-12 days in tropical areas. Such breeding sites may dry up prematurely in the absence of further rainfall, or conversely they can be flushed and destroyed by excessive rains. Once adult mosquitoes have emerged, the ambient temperature, humidity, and rains will determine their chances of survival. To transmit malaria successfully, female Anopheles must survive long enough after they have become infected (through a blood meal on an infected human) to allow the parasites they now harbor to complete their growth cycle ("extrinsic" cycle). That cycle takes 9-21 days at 25°C or 77°F. Warmer ambient temperatures shorten the duration of the extrinsic cycle, thus increasing the chances of transmission. Conversely, below a minimum ambient temperature (15°C or 59°F for Plasmodium vivax, 20°C or 68°F for P. falciparum), the extrinsic cycle cannot be completed and malaria cannot be transmitted. This explains in part why malaria transmission is greater in warmer areas of the globe (tropical and semitropical areas and lower altitudes), particularly for P. falciparum. It has been speculated that current trends of global warming may increase the geographic range of malaria and may be responsible for malaria epidemics. Climate also determines human behaviors that may increase contact with Anopheles mosquitoes between dusk and dawn, when the Anopheles are most active. Hot weather may encourage people to sleep outdoors or discourage them from using bed nets. During harvest seasons, agricultural workers might sleep in the fields or nearby locales, without protection against mosquito bites.

B) Dimming makes it drier and cooler-We solve Helmenstine`7 (Anne, Anne Helmenstine, Ph.D., is an author and consultant with a broad scientific and medical background. Global Dimming & Global Brightening Friday December 28, 2007http://chemistry.about.com/b/2007/12/28/globaldimming-global-brightening.htm)

I mentioned the earth's atmosphere plays a major role in how much light reaches the earth's

surface. Aerosols filter out sunlight, particularly soot particles (from volcanoes or from human activities). Water droplets form around these particles, changing the reflectivity of clouds. If you have more aerosol particles, you have many tiny water droplets in clouds as compared with fewer, larger droplets. Multiple tiny droplets have more surface area, or reflective surfaces, than fewer larger droplets, thereby increasing the amount of light bounced back from clouds. Light from the sun is less likely to reach the earth; radiation from a warm earth is better insulated by the same clouds. The Slate article states that the average amount of light reaching the earth's surface decreased about 10% between 1958 and 1988, however since then, there has been a brightening trend. Was the dimming bad? Is the brightening good? What does it mean? Those are big questions with hotly debated answers. Diminished light can result in less evaporation of water from

the earth's surface which in turn leads to less rain. It also results in cooler temperatures.

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Warming=Dimming in South & East U.S. [1/2] Warming increases smog-causing pollutants in the metropolitan areas of the Southern and Eastern U.S. NRDC`7 (National Resources Defense council, New Study: Smog Poses Greater Health Risk Because of Global Warming, More Bad Air Days for Southern, Eastern U.S. Cities, September 13, 2007http://www.nrdc.org/media/2007/070913.asp) People living in ten mid-sized metropolitan areas are expected to experience significantly more 'red alert' air pollution days in coming years due to increasing lung-damaging smog caused by higher temperatures from global warming. The analysis[1] was prepared by researchers at Yale, Johns Hopkins and Columbia universities, in collaboration with researchers at State University of New York at Albany, and the University of Wisconsin-Madison and released today by the Natural Resources Defense Council (NRDC). The study uses data from the 2007 journal Climatic Change, which looks at climate change, ambient ozone, and public health in U.S. cities. It was released today by NRDC and some of the nation's top medical experts. "The air in many of our nation's cities is already unhealthy. Hotter weather means more bad air days for millions of Americans," said NRDC Climate Center’s Science Director Dan Lashof. "People with asthma are especially at risk, but everyone is adversely harmed by breathing unhealthy air. This research provides another compelling reason to establish enforceable limits on pollution." The study, "Heat Advisory: How Global Warming Causes More Bad Air Days," projects that higher temperatures mean more smog for a given level of precursor emissions. Smog is formed when pollutants from cars, factories, and other sources mix with sunlight and heat. On 'red alert' days -- everyone -particularly children and people with asthma and other respiratory illnesses -- is advised to limit prolonged outdoor exertion. For people with asthma, smog pollution can increase sensitivity to allergens. The Environmental Protection Agency's blue ribbon panel of science advisers has concluded that the current ozone standard of 84 parts per billion (ppb) needs to be substantially reduced to between 60 and 70 ppb in order to protect public health. "EPA should reduce the ozone standard to within the range recommended by its science advisers. A standard at the lower end of that range will save more lives. During warmer months high ozone levels already create breathing problems for children, elderly, and those with respiratory diseases," said Physicians for Social Responsibility's Environment and Health Programs Dr. Director Kristen Welker-Hood. "We know that global warming will lead to higher temperatures, especially in urban areas, and as this study shows, we can expect more and more suffering related to unhealthy air the longer we wait to address global warming." In Washington, D.C., for instance, residents would see a 24 percent drop in clean air days per summer. The report looks at the following cities located in the eastern and southern half of the U.S.: Asheville, NC Cleveland, OH Columbus, OH Greenville, SC Memphis, TN Philadelphia, PA Raleigh, NC Virginia Beach, VA Washington, DC Wilmington, NC These cities are highlighted because of their size, population and geographical differences. Federal policy makers representing these areas will be faced with critical decisions about reducing global warming emissions and it is important that they be made aware of the health implications of hotter temperatures.

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Warming=Dry Heat in Western U.S. Warming will cause the western U.S. to get hotter and drier and the east coast will see more smog Daley`7 ( Beth, Boston Globe Staff Writer, A CLIMATE CHANGE WARNING Panel says humans are probably causing shifts around world, The Boston Globe, April 7, 2007, Lexis)

The report's release in Brussels was delayed for several hours in part because officials of several governments, including the United States, Saudi Arabia, and China, debated wording with scientists, including how the report characterized scientists' certainty that global warming is already influencing physical and biological systems. According to IPCC rules, all governments had to sign off on the document; its release was preceded by four days of intense negotiations with officials from more than 100 countries. The wording was ultimately changed to reflect less certainty, over the objections of the panel's scientists. The final report says it is "likely" that manmade warming has had a discernible influence on many physical and biological systems. "That was a really hard discussion," said Patricia Romero Lankao, a lead author of the report who was part of the Brussels negotiations and who works at the National Center for Atmospheric Research. In a press briefing yesterday morning, a White House official said that any alterations the US pushed for were made to reflect what is really known about the impact of climate change. "We took our role very seriously in getting a summary document that accurately reflects the underlying science," said Sharon Hays, the leader of the US delegation at the Brussels meeting and the associate director for science for the White House Office of Science and Technology Policy. Still, the report's message to government officials around the world was that if emissions of greenhouse gases continue to increase at the current rate, the world will experience a changing environment that plants and animals may not be able to adapt to. If emissions are not curbed, North Americans can expect more heat waves in cities, which tend to be hotter than less populated areas, putting at risk many vulnerable people, including the elderly. Forests will have more wildfires and tree pests, the report predicts, and there could be increased flooding and fiercer storms. The Southwest will get drier. Regions such as the Western United States that get drinking water from melting mountain snow will suffer shortages. The warming temperatures are projected to increase smog in the Eastern United States, with as much as a 68 percent increase in the number of days with poor air quality by 2050. Not all of the news was bad: Crop yields could increase by as much as 20 percent in North America, largely because of longer growing seasons. Cold-related deaths could decrease. While yesterday's report did not address changes specific to New England, scientists have said the region is experiencing pronounced warming that is consistent with global warming. Winter temperatures have risen on average 4.4 degrees in the last 30 years, reducing ice and snow and extending the growing season. More specific regional assessments by the IPCC will be released during the next two weeks. The new 23-page report is a summary of a much longer scientific treatise and is the second of four being produced by the IPCC this year to educate policy makers about the science and predictions of global climate change. The IPCC assessments, issued about every five years since 1990, have shown that scientists are becoming progressively more certain that humans are causing much of the warming. The report two months ago said scientists are more than 90 percent certain that warming temperatures in the last 50 years are mostly due to human activities. The growing weight of scientific evidence was a factor in Monday's US Supreme Court ruling that greenhouse gases are pollutants, a decision that some climate change analysts say may push the Bush administration to regulate carbon dioxide emissions from cars and power plants. IPCC scientists said yesterday they are highly confident they are seeing impacts today of climate change. As part of the report they reviewed 75 studies that showed significant changes in everything from ice on lakes to species' migration. Of those changes, more than 89 percent are consistent with a warming world. Natural variability in temperatures, alone, is unlikely to account for so many changes, the scientists said. "People are beginning to experience global warming in a way they have not before. We are all sensing the changes in the Northeast, the warmer winters, the hotter summers," said Peter Frumhoff, director of science and policy for the Union of Concerned Scientists, a national advocacy group based in Cambridge. Scientists acknowledged in the report that they had too little data to link some recent dramatic climate events to global warming, such as European heat waves.

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Warming=Dimming in South & East Asia Warming produces smog and dimming in south and East Asia while making it hotter and drier in western Asia Mallet`2 (VICTOR, Finnancial Times of London, UN report warns of dangers from Asian brown cloud August 12, 2002, Lexis)

Although smog clouds are often seen in south and east Asia, the Unep report, based primarily on the observations of more than 200 international scientists taking part in a study called the Indian Ocean experiment, is the first detailed assessment of its effects. "It's now absolutely clear that we have a very, very dangerous increase of particulates, especially in the Asian region," Klaus Toepfer, Unep executive director, said at the launch of the report in Paris. The release of the report coincides with preparations for the World Summit on Sustainable Development in Johannesburg later this month. "Our scientists are warning us that this is not only a topic for Asia, but the database in Asia is now the best," Mr Toepfer said. "There are global implications because a pollution parcel like this can travel half way around the globe in the week." The report contains photographs showing the brown haze blanketing the Himalayas below Mt Everest, and says that over the Indian Ocean up to 1,000km downwind of the Indian cities producing the pollution - the smog is "comparable to suburban air pollution in North America and Europe". Among the more alarming findings in the report is that the haze can reduce sunlight reaching the ground by 10 per cent, reducing the productivity of the Asian region's vital rice crop by about the same amount. At the same time, the particles in the haze absorb heat, which can double the heating effect of the sun in the lower atmosphere. The combination of surface cooling and lower atmosphere heating seems to be sharply reducing rainfall in drought-stricken parts of western Asia such as Pakistan and Afghanistan and increasing it further east, where there have been frequent floods. Unep emphasised that its conclusions were preliminary and that further research was urgently needed, particularly into the issue of how the haze interacts with the broader problem of global warming caused by greenhouse gases. Paradoxically, the haze can sometimes counteract global warming, raising the disturbing possibility that moves to reduce smog in the interests of public health could "significantly amplify" global warming over Asia. The report, noting that Asia will have a population of 5bn within three decades, recommends further research and international co-operation to stop the growth of the pollution that causes the brown cloud. The Asian Brown Cloud: Climate and Other Environmental Impacts. Unep/Centre for Clouds, Chemistry and Climate. http://www.rrcap .unep.org

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Fast Warming Worse Aerosols guarantee slow warming, but rapid warming will be disastrous, destroying human society and natural ecosystems, positive feedbacks mean that rapid warming is far more destructive than slow warming Freedman 2005 (Andrew, “Keep warming below threshold to avert 'runaway climate change,' report says”, Greenwire, January 25, 2005) Industrialized nations must join developing countries to limit global warming to 2 degrees Celsius -- or 3.6 degrees Farenheit -- above pre-industrial levels, according to a report released yesterday by the International Climate Change Task Force. Temperature increases beyond that level would increase the risk for disruption of human societies and natural systems, and potentially bring about abrupt or "runaway climate change," the report says. The task force, led by former British cabinet Secretary Stephen Byers and Sen. Olympia Snowe (R-Maine), was established under the auspices of the Institute for Public Policy Research in Britain, the Center for American Progress in the United States, and the Australia Institute. Calling itself a "unique international cross-party, cross-sector collaboration," the task force says its goal is to propose ways to bring the United States and Australia, which both rejected the Kyoto Protocol to limit greenhouse gas emissions, back into multilateral negotiations on climate change. It is also meant to inform the next meeting of the group of eight nations, which will be led by Blair and feature climate change as a key topic. The report "provides ambitious but achievable policy solutions that reach across partisan lines and national boundaries to build momentum for a new global energy agenda that can make important progress on this critical problem," said Center for American Progress President and Chief Executive Officer John Podesta in a statement. The 1992 U.N. Framework Convention on Climate Change, which led to the Kyoto agreement, committed signatories to averting "dangerous" human interference with the climate system but left open the question of what would constitute such interference. "Scientific evidence suggests that there is a threshold of temperature increase above which the extent and magnitude of the impacts of climate change increase sharply," the report states. The 2 degrees Celsius threshold has been increasingly discussed in scientific and policy circles during the past few years and has been adopted as official policy by the European Union, which represents the largest bloc of countries participating in the Kyoto Protocol aimed at reducing greenhouse gases. Meanwhile, the United States has steered clear of any such predictions of a threshold level that would constitute dangerous human interference under the UNFCCC. "No one can say with certainty what that threshold is, but it is important that we make an educated judgment at this time based on the best available science," the task force report states. It found that a net warming of about 2 degrees Celsius likely would be associated with carbon dioxide concentrations above 400 parts per million, a level that is likely to be surpassed on a business as usual emissions scenario as early as the next few decades. The emissions picture is a complicated one, in part because some of the warming effects of the CO2 are blunted by atmospheric particles such as sulfate aerosols, which exert a cooling influence on the climate.

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Methane Wetlands Turn Acid rain deposition of sulfates is currently offsetting warming by decreasing methane emissions from wetlands and rice paddies, but methane-producing microorganisms will recover if sulfur emissions decrease Gauci et al 2005 (Vincent, Department of Earth Sciences, The Open University, “Long-term suppression of wetland methane flux following a pulse of simulated acid rain”, Geophysical Research Letters, June 2005, http://cepsar.open.ac.uk/pers/v.gauci/pics/d43291.pdf) [2] Wetland CH4 emissions are thought to have been the driving factor behind the greenhouse climate of one of Earth’s warmest periods – the early Eocene [Beerling and Valdes, 2002, 2003] and today, together with anthropogenic wetlands (rice paddies), these systems contribute _50% of the global CH4 source [Intergovernmental Panel on Climate Change, 2001]. Aside from occasional large CH4 emission events from CH4 hydrates [Nisbet, 2002], natural wetlands have been the largest contributors of atmospheric CH4 throughout much of geologic time. [3] Recent field experiments have shown that deposition of acid rain sulfate (SO42_) can reduce CH4 emissions from natural wetlands by as much as 40% [Dise and Verry, 2001; Granberg et al., 2001; Gauci et al., 2002; Gauci et al., 2004b]. Inputs of SO4 2 _ to wetlands stimulate sulfate reducing microbial populations [Vile et al., 2003] that then out-compete CH4-producing micro-organisms, thus circumventing the degradation pathway of carbon to CH4 and resulting in a reduction in CH4 emission [Gauci et al., 2002]. Sulfate deposition from acid rain significantly reduced global wetland CH4 emission since the middle of the 20th century, off-setting any CH4 increase due to climate warming [Gauci et al., 2004a]. [4] This effect is likely to continue during the first half of the 21st century [Gauci et al., 2004a]. Uncertainty remains, however, over the recovery time for methane emissions following a relief in acid rain. This is relevant to two situations. First, large-scale atmospheric release of SO2 through industrialisation which began some 150 years ago has raised sulfate deposition levels in many areas of central Europe and, more recently (ca 100 years ago) in North America, to levels from 5 to 50 times higher than natural background deposition [Rodhe, 1999]. Since the early 1980s, this pollution has dramatically declined, but its impact on methane emissions may have barely diminished if S-recycling is prolonged.

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Methane Wetlands Turn Air pollution is key to preventing methane and carbon releases from wetlands and peat bogs, solving the acid rain problem would only create a rapidly escalating global warming Gauci 2005 (Vincent, Department of Earth Sciences, The Open University, “Acid interactions”, Planet Earth, Autumn 2005, http://cepsar.open.ac.uk/pers/v.gauci/pics/d50568.pdf) Pollution is a ‘bad thing’ right? If only things were that simple! New research suggests acid rain falling on wetlands could be helping to keep greenhouse gases in check. Earth’s wetlands store vast amounts of carbon. Water-loving plants like sphagnum mosses photosynthesise, turning carbon dioxide into plant material that builds up soggy, carbon-rich soils over thousands of years. In peatlands—just one form of wetland —there’s as much carbon locked away in the soil as is contained in the atmosphere. Carbon dioxide isn’t the only gas that moves between wetlands and the atmosphere. These ecosystems emit vast quantities of methane, a greenhouse gas that, molecule for molecule, is about 20 times more powerful than carbon dioxide. Microbes called methanogens, which thrive in waterlogged and oxygen-free conditions, produce methane. Wetlands are the largest global source of the gas. There are wetlands in Europe and the United States, but most are found in remote areas of the world such as Siberia and northern Canada, and in the tropics, for example Indonesia and the Pantanal in South America. At the Open University, we realised that although most wetlands are far from big industrial centres, some of these important ecosystems could still be susceptible to atmospheric pollution. Could pollution affect the amount of methane wetlands emit? We decided to investigate the sulphur pollution that is found in acid rain. Many countries, particularly in Western Europe and North America, have taken great strides to reduce this problem since the 1980s. But globally, the problem continues to grow, roughly keeping pace with the economic growth of Asia. Volcanoes are also important sources of sulphur, and over the Earth’s history they have been the main ‘polluters’. For example, the Icelandic Laki eruption of 1783-84 emitted as much sulphur as Western Europe’s industry would over ten years. In Moidach More, a peat bog in north-east Scotland, my colleagues (Nancy Dise, now at Manchester Metropolitan University, and David Fowler of the Centre for Ecology & Hydrology, Edinburgh) and I simulated the sulphate deposition that acid rain still brings to polluted parts of the world. The experiment also simulated the amount and timing of acid rain that would have come from the Laki eruption. Our monitoring showed that the pollution actually reduced methane emissions by 30-40%. The reason for this is that the sulphate component of acid rain pollution sparks a battle between different microbial populations that live in the peat. Most peatland organisms get their nutrients from elements dissolved in rain and snow – and normally there’s very little sulphate. Under these conditions, methane production is the last step as plant matter decomposes. But even the very small amounts of sulphate in acid rain can shift the balance of microbial power. A different set of microbes, called sulphate-reducing bacteria, now succeeds in the battle for limited food sources within the peat. They out-compete the methanogens, leaving them without much food, so less methane is produced. It’s one thing to find out that simulated acid rain can reduce emissions from a single peat bog experiment, but quite another to find out whether or not the interaction is important globally. So with colleagues at the NASA Goddard Institute for Space Studies (GISS), we drew together the results of similar experiments in Sweden and North America. With the help of a global wetland methane emission model, and estimates of sulphur deposition from our colleagues’ model of the world’s atmosphere, we were able to make an estimate at the global scale. The results surprised us. Without the effect of sulphur from industrial sources, wetlands would become an increasingly large source of methane as climate warms. This is because more methane is produced as temperatures rise. But when we included acid rain in our model, we found that sulphate pollution offsets the effect of warmer temperatures, bringing global methane emissions from wetlands down to preindustrial levels. Intriguing questions arose from this work: What would happen if you solved the acid rain problem in Asia? Would methanogens in wetlands, suddenly relieved of sulphate input from acid rain, immediately fight back against the competitive sulphate-reducing bacteria?

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Methane Wetlands - Unique Link Sulfate deposition is currently suppressing methane emissions from wetlands and will continue to do so in the status quo as Asian demand for energy increases Gauci 2004 (Vincent Gauci, Department of Earth Sciences, Open University, “Sulfur pollution suppression of the wetland methane source in the 20th and 21st centuries”, Environmental Sciences, http://cepsar.open.ac.uk/pers/v.gauci/pics/d39285.pdf) The distinct pattern that arises on combining both the sulfate reduction data with the acid rain manipulation experiments (Fig. 1) leads us to conclude that not only does the potential exist for suppression of methane emission by sulfate deposition, but this suppression is currently occurring and has occurred in the past. Given that sulfur pollution varies both spatially and temporally across the planet, and that projections of population growth and energy consumption in Asia suggest that the problem of sulfur pollution will continue to increase in the first half of this century (27), it is important to examine how this mechanism may have an impact on the wetland CH4 source in the future. To date, no study has quantitatively examined the extent to which areas experiencing enhanced sulfur deposition (SDEP) spatially coincide with CH4-producing wetlands. Here, we estimate the potential for this mechanism to affect both the northern wetland methane source and global wetlands as a whole and estimate the changing importance of atmospheric SO4 2 pollution on CH4 emission during both the 20th and 21st centuries.

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Methane Wetlands Turn – Must Read Natural wetlands and rice paddies are a potentially huge source of methane, a potent greenhouse gas. Sulfate aerosols prevent methane production by keeping the wetlands cool and encouraging sulfur-reducing bacteria, preventing a massive spike in global warming Gauci 2004 (Vincent Gauci, Department of Earth Sciences, Open University, “Sulfur pollution suppression of the wetland methane source in the 20th and 21st centuries”, Environmental Sciences, http://cepsar.open.ac.uk/pers/v.gauci/pics/d39285.pdf) Natural wetlands form the largest source of methane (CH4) to the atmosphere. Emission of this powerful greenhouse gas from wetlands is known to depend on climate, with increasing temperature and rainfall both expected to increase methane emissions. This study, combining our field and controlled environment manipulation studies in Europe and North America, reveals an additional control: an emergent pattern of increasing suppression of methane (CH4) emission from peatlands with increasing sulfate (SO4 2 -S) deposition, within the range of global acid deposition. We apply a model of this relationship to demonstrate the potential effect of changes in global sulfate deposition from 1960 to 2080 on both northern peatland and global wetland CH4 emissions. We estimate that sulfur pollution may currently counteract climate-induced growth in the wetland source, reducing CH4 emissions by 15 Tg or 8% smaller than it would be in the absence of global acid deposition. Our findings suggest that by 2030 sulfur pollution may be sufficient to reduce CH4 emissions by 26 Tg or 15% of the total wetland source, a proportion as large as other components of the CH4 budget that have until now received far greater attention. We conclude that documented increases in atmospheric CH4 concentration since the late 19th century are likely due to factors other than the global warming of wetlands.

Atmospheric methane (CH4) is a powerful greenhouse gas (GHG) that is responsible for an estimated 22% of the present anthropogenically enhanced greenhouse effect (1). Natural (nonrice agriculture) wetlands are the world’s largest single CH4 source and are estimated to currently contribute between 110 and 260 Tg (Tg 1012 g) to the global methane budget (2), of which one-third is derived from temperate and boreal northernwetlands (3). CH4 emissions from wetlands are climate sensitive, responding positively to increases in temperature and rainfall as microbial activity and anaerobic conditions increase and negatively to cool temperatures and drought (4, 5). Like many other ecosystems, wetlands are also subject to the effects of aerial pollution and increasing CO2 levels. The stimulatory effects of increased atmospheric CO2 concentrations on CH4 emission (by enhancement of net primary productivity) is well reported (6–8), although a similar stimulatory effect of nitrogen pollution on wetland CH4 emission has not always been identified (8–10) because of differing effects nitrogen has on the ecosystem, e.g., plant species composition is an important factor in determining the effect of experimental N additions on CH4 fluxes (10). CH4 is produced by two different groups of methanogenic archaea (MA); one group obtains energy by the fermentation of simple organic compounds, such as acetate to CO2 and CH4, and the other obtains energy by oxidizing molecular hydrogen to H2O by using CO2, which is reduced to CH4. Acetatefermenting MA tend to dominate in more nutrient-rich peatlands and in summer, when the supply of labile organic carbon is relatively high. However, it has been recently demonstrated that climate, depth of the acrotelm, and acetate concentrations add a fair degree of plasticity over controls on acetate-fermenting MA (11). Both groups of microorganisms are strictly anaerobic, and both are suppressed by another group of anaerobic microorganisms, sulfate-reducing bacteria (SRB) (12). SRB have a higher affinity for both hydrogen and acetate than MA, which, under ideal conditions, enables them to maintain the pool of these substrates at concentrations too low for MA to use (13, 14). In wetlands, however, the balance between sulfate reduction and methanogenesis is affected by factors such as the temperature [warmer temperatures favor methanogenesis (15)], the rate of SO4 2 and acetate supply [lower concentrations of sulfate or higher concentrations of acetate reduce the intensity of competition (13)], and the availability of noncompetitive substrates [some low molecular weight hydrocarbons may be preferentially used over acetate by SRB (16, 17) and some substrates such as methanol, methanethiol, and dimethyl sulfide may be used by MA but are poorly used by SRB (18, 19)]. As a consequence, sulfate reduction in wetlands partially, rather than completely, inhibits methane production (19). Stimulation of sulfate reduction has been exploited as a mechanism to reduce GHG emissions from rice paddies; in field trials, CH4 emissions have been reduced by as much as 72% with doses of gypsum (CaSO4) ranging from several hundred to thousands of kilograms of SO4 2 per hectare (ha) (20, 21).

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Methane Wetlands Turn – Must Read Air pollution is key to preventing methane and carbon releases from wetlands and peat bogs, solving the acid rain problem would only create a rapidly escalating global warming Gauci 2005 (Vincent, Department of Earth Sciences, The Open University, “Acid interactions”, Planet Earth, Autumn 2005, http://cepsar.open.ac.uk/pers/v.gauci/pics/d50568.pdf) Pollution is a ‘bad thing’ right? If only things were that simple! New research suggests acid rain falling on wetlands could be helping to keep greenhouse gases in check. Earth’s wetlands store vast amounts of carbon. Water-loving plants like sphagnum mosses photosynthesise, turning carbon dioxide into plant material that builds up soggy, carbon-rich soils over thousands of years. In peatlands—just one form of wetland —there’s as much carbon locked away in the soil as is contained in the atmosphere. Carbon dioxide isn’t the only gas that moves between wetlands and the atmosphere. These ecosystems emit vast quantities of methane, a greenhouse gas that, molecule for molecule, is about 20 times more powerful than carbon dioxide. Microbes called methanogens, which thrive in waterlogged and oxygen-free conditions, produce methane. Wetlands are the largest global source of the gas. There are wetlands in Europe and the United States, but most are found in remote areas of the world such as Siberia and northern Canada, and in the tropics, for example Indonesia and the Pantanal in South America. At the Open University, we realised that although most wetlands are far from big industrial centres, some of these important ecosystems could still be susceptible to atmospheric pollution. Could pollution affect the amount of methane wetlands emit? We decided to investigate the sulphur pollution that is found in acid rain. Many countries, particularly in Western Europe and North America, have taken great strides to reduce this problem since the 1980s. But globally, the problem continues to grow, roughly keeping pace with the economic growth of Asia. Volcanoes are also important sources of sulphur, and over the Earth’s history they have been the main ‘polluters’. For example, the Icelandic Laki eruption of 1783-84 emitted as much sulphur as Western Europe’s industry would over ten years. In Moidach More, a peat bog in north-east Scotland, my colleagues (Nancy Dise, now at Manchester Metropolitan University, and David Fowler of the Centre for Ecology & Hydrology, Edinburgh) and I simulated the sulphate deposition that acid rain still brings to polluted parts of the world. The experiment also simulated the amount and timing of acid rain that would have come from the Laki eruption. Our monitoring showed that the pollution actually reduced methane emissions by 30-40%. The reason for this is that the sulphate component of acid rain pollution sparks a battle between different microbial populations that live in the peat. Most peatland organisms get their nutrients from elements dissolved in rain and snow – and normally there’s very little sulphate. Under these conditions, methane production is the last step as plant matter decomposes. But even the very small amounts of sulphate in acid rain can shift the balance of microbial power. A different set of microbes, called sulphate-reducing bacteria, now succeeds in the battle for limited food sources within the peat. They out-compete the methanogens, leaving them without much food, so less methane is produced. It’s one thing to find out that simulated acid rain can reduce emissions from a single peat bog experiment, but quite another to find out whether or not the interaction is important globally. So with colleagues at the NASA Goddard Institute for Space Studies (GISS), we drew together the results of similar experiments in Sweden and North America. With the help of a global wetland methane emission model, and estimates of sulphur deposition from our colleagues’ model of the world’s atmosphere, we were able to make an estimate at the global scale. The results surprised us. Without the effect of sulphur from industrial sources, wetlands would become an increasingly large source of methane as climate warms. This is because more methane is produced as temperatures rise. But when we included acid rain in our model, we found that sulphate pollution offsets the effect of warmer temperatures, bringing global methane emissions from wetlands down to preindustrial levels. Intriguing questions arose from this work: What would happen if you solved the acid rain problem in Asia? Would methanogens in wetlands, suddenly relieved of sulphate input from acid rain, immediately fight back against the competitive sulphate-reducing bacteria?

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Wetlands Methane - Aerosols Decrease Methane Air pollution suppresses methane emissions from wetlands, offsetting global warming Gauci and Chapman 2006 (Vincent Gauci, Department of Earth Sciences at the Open University, and Stephen Chapman, The Macaulay Institute, “Simultaneous inhibition of CH4 efflux and stimulation of sulphate reduction in peat subject to simulated acid rain”, Soil Biology & Biochemistry, July 5, 2006, http://cepsar.open.ac.uk/pers/v.gauci/pics/d62057.pdf) Sulphur pollution in the form of acid rain is a known suppressant of CH4 emitted from natural wetlands (e.g. Gauci et al., 2002, 2004b). This important biogeochemical interaction is thought to offset global warming induced increases in wetland CH4 emissions (Gauci et al., 2004b) and extend the duration of any atmospheric impact of volcanic eruptions (Gauci et al., 2005). The mechanism responsible has always been assumed to be exclusion of methanogens from electron donors by stimulation of a competitively superior population of SO4 reducing bacteria (SRB). Although rates of dissimilatory sulphate reduction have been found to increase along a global transect of increasing sulphur pollution (Vile et al., 2003b), to our knowledge no study has reported evidence of atmospheric depositionenhanced sulphate reducing activity that also coincides with suppression in CH4 emission in the field. Isolation of SRB in low pH environments such as peat bogs remains elusive (Chapman, 2001) and so peatland populations of SRB have proved difficult to quantify. Despite this limitation, workers have used the radioactive 35 SO4 tracer method to estimate rates of dissimilatory sulphate reduction, which has improved our understanding of the importance of SRB populations in determining carbon flow in peat soils (Wieder et al., 1990; Nedwell and Watson, 1995; Watson and Nedwell, 1998; Vile et al., 2003a). In this study, we estimated sulphate reduction over seasonal intervals for peat samples from a site that had experienced historically low rates of ambient SO4 2 deposition (control) as well as from plots that were experimentally manipulated with enhanced SO4 2 deposition rates (50 kg SO4 2 -S ha 1 yr 1) over a period of 18 months.

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Wetlands Methane - Aerosols Decrease Methane Acid rain suppresses methane emissions from wetlands by increasing microbial diversity and competition, reducing the greenhouse effect Gauci et al 2005 (Vincent, Department of Earth Sciences, The Open University, “Long-term suppression of wetland methane flux following a pulse of simulated acid rain”, Geophysical Research Letters, June 2005, http://cepsar.open.ac.uk/pers/v.gauci/pics/d43291.pdf) [1] Wetlands are a potent source of the radiatively important gas methane (CH4). Recent findings have demonstrated that sulfate (SO4 2 _) deposition via acid rain suppresses CH4 emissions by stimulating competitive exclusion of methanogens by sulfate-reducing microbial populations. Here we report data from a field experiment showing that a finite pulse of simulated acid rain SO4 2 _ deposition, as would be expected from a large Icelandic volcanic eruption, continues to suppress CH4 emissions from wetlands long after the pollution event has ceased. Our analysis of the stoichiometries suggests that 5 years is a minimum CH4 emission recovery period, with 10 years being a reasonable upper limit. Our findings highlight the long-term impact of acid rain on biospheric output of CH4 which, for discrete polluting events such as volcanic eruptions, outlives the relatively short-term SO4 2_ aerosol radiative cooling effect.

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Wetlands Methane - Research Proves Research data proves that acid rain increases Sulfur Reducing Bacteria in wetlands, decreasing methane emissions Gauci and Chapman 2006 (Vincent Gauci, Department of Earth Sciences at the Open University, and Stephen Chapman, The Macaulay Institute, “Simultaneous inhibition of CH4 efflux and stimulation of sulphate reduction in peat subject to simulated acid rain”, Soil Biology & Biochemistry, July 5, 2006, http://cepsar.open.ac.uk/pers/v.gauci/pics/d62057.pdf) To conclude, results from this experiment show that after 18 months of small regular additions of SO4 2 , at inputs equivalent to that experienced in regions affected by acid rain (50 kg-S ha 1 yr 1), the estimated sulphate reduction rate is up to 10 times larger than in control plots where ambient S deposition rate is one-tenth that of treatment plots. This tenfold increase in SO4 2 reduction indicates the presence of a more active population of SRB in plots where CH4 emissions were concomitantly reduced by over 30%.

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Wetlands Methane - Time Frame / Studies Experimental data shows that methane reduction from sulfate deposition occurs for about five years Gauci et al 2005 (Vincent, Department of Earth Sciences, The Open University, “Long-term suppression of wetland methane flux following a pulse of simulated acid rain”, Geophysical Research Letters, June 2005, http://cepsar.open.ac.uk/pers/v.gauci/pics/d43291.pdf) [15] Comparing the total number of moles of CH4 suppressed from 1997–2000 (with 1999 methane emissions estimated as a mean of CH4 emissions in 1998 and 2000) with the total molar amount of SO4 2_ that had been deposited during the experimental manipulation period gives an average of 7, 3, and 2 moles CH4 suppressed for each mole of SO42_ applied in the 25, 50 and 100 kg SO42_ - S ha_1 yr_1 treatments, respectively (Table 1). If the CH4: SO4 2 _ ratio of 7 for the 25 kg SO4 2 _ - S ha_1 yr_1 treatment is a maximum, and CH4 emissions return to control levels two years after the end of the treatment, this would indicate that CH4 flux suppression from the 50 and 100 kg SO42_ -S ha_1yr_1 treatments would continue beyond this 2year post-pollution event period. Indeed, assuming that control CH4 emissions in subsequent years continue at an average of 1998 and 2000 rates, it would indicate that the 50 and 100 kg SO4 2 _ - S ha_1yr_1 treatments would recover between 5 and 6.5 years, respectively, after the end of the experimental pollution episode. The directly measured CH4 emissions in 2003 (Figure 1) are consistent with these results.

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Wetlands Methane - Time Frame Methane emissions from wetlands will resume several years after sulfur deposition reductions Gauci et al 2005 (Vincent, Department of Earth Sciences, The Open University, “Long-term suppression of wetland methane flux following a pulse of simulated acid rain”, Geophysical Research Letters, June 2005, http://cepsar.open.ac.uk/pers/v.gauci/pics/d43291.pdf) [18] For industrial deposition and deposition resulting from longer-term volcanic activity (i.e. associated withLarge Igneous Provinces [Thordarson and Self, 1996; Self et al., 2003]) which has been persistently elevated for decades, this recovery period could well be longer. The rate of recovery under both short and long-term deposition scenarios is critically dependent on the fate of the ‘old’ sulfur deposited in the preceding years or decades. If most of the old sulfur is stored in relatively inert organic compounds [Chapman, 2001], then sulfate reducers may depend upon recently-deposited SO4 2_. In this case, recovery of CH4 emission could occur within several years of a significant reduction in acid deposition.

Methane reductions from sulfate aerosols last for approximately five years Gauci et al 2005 (Vincent, Department of Earth Sciences, The Open University, “Long-term suppression of wetland methane flux following a pulse of simulated acid rain”, Geophysical Research Letters, June 2005, http://cepsar.open.ac.uk/pers/v.gauci/pics/d43291.pdf) [13] Fluxes measured in 2003 (5 years after the end of the simulated pollution event) were exceptionally small in all treatments and controls due to a particularly dry summer. There were no significant differences (at the P = 0.05 level) between treatments and controls (Figure 1c), nor between individual treatments. There are two possible interpretations of the 2003 results. One is that the CH4 fluxes from SO4 2 _ treated plots had completely recovered and were therefore indistinguishable from control emissions (Figure 1c).

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Wetlands Methane - Impact + Neg Studies Indite Sulfates suppress wetlands emission of methane. Methane is a powerful greenhouse gas, equivalent to half of all anthropogenic CO2 emissions, but their models leave it out of their calculations. Gauci 2004 (Vincent Gauci, Department of Earth Sciences, The Open University, “Sulfate deposition and temperature controls on methane emission and sulfur forms in peat”, Biogeochemistry 71, 2004, http://cepsar.open.ac.uk/pers/v.gauci/pics/d39284.pdf) Atmospheric methane (CH4) is a powerful greenhouse gas that has contributed 50% as much enhanced greenhouse forcing as anthropogenically enhanced levels of CO2 since 1850 (Hansen et al. 2000). Wetlands form the largest source of methane to the atmosphere and feedbacks affecting output from this natural source are of considerable interest. One such feedback, the suppressive effect of sulfate (SO2 4 ) deposition through acid rain, has only recently been considered (Watson and Nedwell 1998; Dise and Verry 2001; Granberg et al. 2001; Gauci et al. 2002). As a result, few studies have simultaneously investigated both the effect of low but repeated doses of SO2 4 on CH4 emissions and the effects of increased sulfur (S) deposition on S fluxes and pools in peatlands, a critical store of S in terrestrial ecosystems (Wieder and Lang 1988; Wieder et al. 1990). Some evidence suggests, furthermore, that the extent of suppression may be controlled by temperature (Bodegom and Stams 1999; Granberg et al. 2001; Gauci et al. 2002). With the prospect of changes in atmospheric SO2 4 deposition as well as current and future climate change it is important to begin to quantify these complex interactions. In particular, atmospheric chemical and climate models may need to take into account suppression of CH4 emission by SO2 4 in future climate-change scenarios.

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Wetlands Methane - Positive Feedback Sulfate suppression of wetlands methane decreases with temperature increases, creating a positive feedback Gauci 2004 (Vincent Gauci, Department of Earth Sciences, Open University, “Sulfur pollution suppression of the wetland methane source in the 20th and 21st centuries”, Environmental Sciences, http://cepsar.open.ac.uk/pers/v.gauci/pics/d39285.pdf) Taken together, our experiments reveal an emergent pattern of suppression of methane emission by sulfate (Fig. 1, filled circles). With respect to control sites where no sulfate was added, suppression of CH4 increases from 12% to 30% as the experimental sulfate additions increase from 10 to 20 kg SO4 2-S ha1 yr1. Above this level of experimental sulfate deposition, CH4 suppression increases to 30–45%. All our studies also show that the level of suppression is significantly reduced (CH4 emission began to recover, in some cases approaching control levels) during times when the peatlands are warmer. This reduction in the sulfur effect may be due to enhanced decomposition rates at higher temperatures, allowing more dissolved carbon to become available to the whole microbial community, or to temperature sensitivity in the competition between acetoclastic methanogens and SRB (15).

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Wetlands Methane - AT: We Overestimate If anything, the studies underestimate the impact of sulfates on methane emissions reductions from wetlands Gauci 2004 (Vincent Gauci, Department of Earth Sciences, Open University, “Sulfur pollution suppression of the wetland methane source in the 20th and 21st centuries”, Environmental Sciences, http://cepsar.open.ac.uk/pers/v.gauci/pics/d39285.pdf) Model Assumptions. A number of simplifications and uncertainties are related to our approach. Our major assumption is that the only source of sulfate to these freshwater wetlands is from the atmosphere (the SDEP model includes all sources of sulfate, including natural sources from volcanoes and biogenic sulfur production). Although we eliminate saltwater marshes and mangrove swamps (both in high-sulfate marine environments) from our database, it is certain that some wetlands have significant local sulfate sources from bedrock, sediments, or groundwater throughflow. We have no way of estimating the magnitude of this existing sulfate effect, although globally, sulfide-rich rocks are much rarer than silicate or carbonate rocks. Although this would suggest that our findings should be considered as maximum effects, the trajectory of recovery in CH4 fluxes when SDEP is relieved and the factors governing recovery remain poorly understood. The estimates reported here assume an immediate return to normal, preSO4 2 rates of CH4 emission. However, peatlands are net sinks of sulfur, which undergoes reduction and oxidation over short and long timescales (hours and years), moving between pools of varying biological availability, resulting in a likely extension to the duration of its impact on CH4 emission (24, 36, 37). In this respect, any extrapolation is likely to be underestimating the size and duration of the effect of sulfur on wetland methane fluxes.

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Wetlands Methane - AT: Volcanoes Acid rain allows methane reduction at sustainable levels, but methane producing bacteria recover in a matter of weeks. Large single applications of sulfur, such as from volcanoes, have a very short duration of methane suppression Gauci 2004 (Vincent Gauci, Department of Earth Sciences, The Open University, “Sulfate deposition and temperature controls on methane emission and sulfur forms in peat”, Biogeochemistry 71, 2004, http://cepsar.open.ac.uk/pers/v.gauci/pics/d39284.pdf) Most early work investigating a link between S deposition and suppression of CH4 emissions involved the application of large single applications of SO2 4 (e.g. Fowler et al. 1995; MacDonald 1997). Through manipulation of S inputs to intact peat monoliths with large individual SO2 4 doses amounting to 40 kg SO2 4 -S ha 1 year 1, Fowler et al. (1995) found that emissions decreased over time in treated plots reaching a maximum 40% suppression relative to controls after around 3 weeks. This was followed by a period of recovery, where treated monoliths reach pre-treatment levels after about 4 additional weeks. It has been suggested, however, that the high, but ‘onetimeonly’ applications of SO2 4 in single dose studies may be less efficient at sustained lowering of CH4 fluxes than continuous low-level deposition of SO2 4 (Fowler et al. 1995; Arah and Stephen 1998). The hypothesis is that such large single pulses of SO2 4 may stimulate a ‘boom – bust’ cycle amongst SO2 4 -reducing bacteria (SRB) populations, prompting rapid recovery of methane fluxes several weeks after the treatment application as the labile SO2 4 pool decreases (Arah and Stephen 1998). More recent work has sought to more closely approximate the chronic deposition of SO2 4 in acid rain by the application of numerous small doses of SO2 4 (Dise and Verry 2001; Granberg et al. 2001; Gauci et al. 2002). Dise and Verry (2001) enhanced SO2 4 input to a bog over a 12 week period by applying individual doses of SO2 4 amounting to 2.7 kg of SO2 4 -S per week (giving an annualized deposition rate of 145 kg Sha 1 year 1 – at the extreme high end of deposition experienced in acid rain impacted areas) and found that subsequent CH4 emissions were suppressed by around 30%. More recently, Gauci et al. (2002) applied far smaller pulses of S, amounting to annual deposition rates as low as 25 kg S ha 1 year 1 over 2 years and reflecting S deposition rates in moderately impacted areas of Europe. They found that CH4 fluxes were suppressed by around 40% annually and calculated that SO2 4 would have to have been recycled 5 times to sustain the suppression that was observed. Through the application of regular small pulses of SO2 4 it is likely that the continuous supply of low levels of SO2 4 may maintain SRB at elevated, competitive levels (Dise and Verry 2001; Gauci et al. 2002). Clearly it is important to examine how S is cycled within peatlands as S added as SO2 4 may be ‘lost’ either through gaseous emission from the peat as volatile reduced S compounds or through conversion to biologically recalcitrant forms. The two modes of SO2 4 deposition (a single large application and small regular pulses) have not, thus far been directly compared.

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Dimming-AT: “Most Aerosols are natural” Only 25% of all aerosols are natural, they shift with the seasons, and they contribute to global warming Griffith`5 (VICTORIA, The financial times of London, Natural pollutants take their toll SCIENCE BRIEFING, April 1, 2005 Friday, Lexis)

Fur fibres, dandruff, skin fragments and other biological particles contribute much more to air pollution than previously thought, say scientists, a finding that may complicate efforts to curb global warming. Aerosols suspended particles in the atmosphere - have long been cited as an important trigger of ozone depletion and global warming. Until a study, published today in Science, however, natural contributors were considered an insignificant component of such pollution, as environmentalists focused on man-made pollutants. German researchers found that up to 25 per cent of aerosol particles - depending on location and time of year - consisted of biological compounds. Because such compounds are beyond the reach of most environmental controls, cleaning them up poses a challenge to governments trying to reduce the greenhouse effect. The impact of natural aerosols shifts with the seasons. Levels of pollen, which encourage the formation of clouds, rise in the spring. Decaying vegetation and marine plankton, which trigger rain and snow, prevail in winter months. The composition of atmospheric aerosols also depends on geographic location. Over Ireland, for instance, marine cells were a source of aerosol pollution.

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Dimming-AT: Previous studies All previous brown cloud studies are flawed-They don’t assume seasonal changes Ramanathan et al 2005 (V. Ramanathan, C. Chung, D. Kim, T. Bettge, L. Buja, J. T. Kiehl, W. M. Washington, Q. Fu, D. R. Sikka, M. Wild, Atmospheric Brown Clouds: Impacts on South Asian Climate and Hydrological Cycle, National Academy of Sciences, Apr. 12, 2005, Jstor)

The earlier modeling studies (9, 10) of the South Asian brown clouds provided interesting results about the connections between aerosols and rainfall but made several limiting assumptions. The earlier studies were conducted with prescribed sea surface temperatures (SSTs) and thus did not account for the response of the SSTs to aerosol forcing. They also did not account for the seasonal variation of the forcing, and both of these were major factors in the simulated climate changes. More importantly, the earlier studies were equilibrium simulations with ABC forcing held fixed at current values and, thus, could not examine the impact of the haze on the 20th-century climate trends. It was the comparison of the simulated with the observed trends that provided crucial new insights into the role of ABCs. Thus, the present study revisits the issue with a more comprehensive approach.

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Dimming-AT: “Dimming doesn’t assume all pollution” Recent studies take into account all forms of pollution, and different levels of absorption Liepert`6Beate (Doherty Research Scientist at Lamont-Doherty Earth Observatory of Columbia University.) http://www.realclimate.org/index.php/archives/2006/04/global-dimming-and-climate-models/

Global dimming is the phenomena of an observed reduction (about 1-2% per decade since ~1960) of sunlight reaching the surface of the Earth caused by air pollution (aerosols – small particles) and cloud changes. Some of this solar energy is reflected back out to space and this cooling effect is believed to have counteracted part of the greenhouse gas warming. The original version of the film focused mainly on the observational recognition of global dimming, but one aspect did not receive much attention in the film - namely the oft-claimed lack of global dimming in climate models. This led some to assume that climate modelers were ignoring air pollution other than greenhouse gases emissions from fossil fuel burning. Another implication was that climate models are not capable of adequately simulating the transfer of sunlight through the atmosphere and the role of clouds, sunlight extinction of aerosols and aerosol effects on clouds etc, and therefore model projections should not be trusted. The NOVA version will address this issue more prominently by adding an interview with Jim Hansen from NASA Goddard Institute for Space Studies. Along this line, I’d like to elaborate on aerosols in climate models in more detail. It is indeed true that the first climate change simulations were predominantly concerned with greenhouse gas forced climate change. Albeit very early papers argue that man-made aerosol changes might cause a cooling (Rasool and Schneider, Science 1971 and Bryson, Science 1974). And already in 1990, J. Hansen and A. Lacis (Science 1990) published a paper where they explicitly discuss the importance of anthropogenic aerosol forcing: “Sun and Dust versus Greenhouse Gas Forcing”. The authors list direct effects of increasing concentrations of light scattering sulfate aerosols, light absorbing carbonaceous aerosols like soot and even aerosol effects on cloud properties (indirect aerosol effects). Finally they conclude that “… solar variability will not counteract greenhouse warming and that future observations will need to be made to quantify the role of tropospheric aerosols … ”. The surface dimming effect was not yet considered an important climate factor. Back then, state-of-the-art climate models changed the reflectivity at the top of the atmosphere to account for the climate effect of increases in man-made aerosol emissions. Using cloud properties from independent climate simulations and weather forecast models to provide monthly mean water vapor and temperature fields, Kiehl and Briegleb (Science 1993) estimated a top of the atmosphere global mean human-related sulfate aerosol forcing of -0.3 W/m2 in contrast to the a +2.1 W/m2 greenhouse gas forcing. A year later, Jones, Roberts and Slingo (Nature 1994) added the indirect aerosol effect - the impact of increasing sulfate aerosol concentrations on cloud droplet sizes - which make look cloud darker. They used empirical relations to link the number of aerosol particles and number of cloud droplets to cloud droplet radii for their estimates. Other groups as well, started testing new prognostic cloud schemes for general circulation models that were able to capture the microphysical processes of cloud formation (e.g. MPI in Hamburg - Lohmann and Roeckner, Climate Dynamics 1996). These climate-modeling developments were compared (Wild et al., JC 1995) with the then available observational data of the surface solar radiation (incidentally the same data sets were used by Russak (Tellus 1990), Stanhill and Moreshet (Climatic Change 1992) and myself (Liepert et al., Contr. Atm. Physics 1994) to reconstruct the history of global dimming). One conclusion was that then-current models did not include enough aerosol absorbtion in the atmosphere (and Wild and I (GRL, 1998) wrote a paper on the “Excessive Transmission of Solar Radiation Through the Cloud-free Atmosphere in GCMs”). Note that at the end of 1990s these more complex climate models with a more physically based prognostic cloud scheme were run as equilibrium experiments hence transient 20th Century changes could not be used directly for comparison. But is has always been clear that anthropogenic aerosols are so temporally and spatially variable that long-term means are not adequate in assessing the actual aerosol forcing. Several publications on model validations and improvements based on surface solar radiation records followed and I was involved in two of these studies. We analyzed the simulated multi-decadal changes in the direct tropospheric aerosol forcing in the NASA GISS GCM and utilized global dimming time series of the United States and Germany to assess the temporal change prognosed in the model (Liepert and Tegen, JGR 2002). Ina Tegen’s aerosol model was one of the first that added time variations in carbonaceous aerosol components (including black carbon – an absorbing aerosol). We concluded that increasing absorption might actually play a stronger role than expected.

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Dimming-AT: Asian SO2 Solves China’s cleaning up now-Olympics Reuters 6/19/08 http://www.reuters.com/article/latestCrisis/idUSPEK134123 China's capital has spent 140 billion yuan ($20.34 billion) to combat chronic pollution and create a clean, green Beijing ahead of the Aug. 8-24 Olympics. Here are some of the measures the city, home to 15 million people and 3 million cars, is taking to green up: SWITCHING TO GAS FROM COAL: -- Already the top consumer of natural gas among Chinese cities, Beijing's usage grew to an estimated 4.7 billion cubic metres in 2007 as it tried to cut back on the 26 million tonnes of polluting coal it consumes a year. -- By the end of 2006, 15,200 coal-fired boilers, out of 16,300 in the city, had been converted to natural gas or other clean fuels. CLOSING OR RELOCATING HEAVY POLLUTERS: -- Steel-maker Capital Steel, long Beijing's worst polluter, has relocated most operations out of the city to coastal Hebei province, with the rest to follow by 2010. -- In July 2006, production ceased at another major polluter, the Beijing Coking and Chemical Factory, which had been responsible for 7,300 tonnes of dust and 7,500 tonnes of sulphur dioxide in annual emissions. GREENING THE TRANSPORT SYSTEM: -- To cut pollution from private cars, which pump out 80 percent of the carbon monoxide in Beijing skies, new emission standards implemented in 2005 were tightened in January 2008. -- A new north-south subway line opened in October 2007. Ticket prices were set at two yuan (about 29 cents) to woo commuters off the roads. Spectators with Olympics tickets will travel free on public transport during the Games. -- Beijing retired or refitted 47,000 old taxis, and about 7,000 old diesel buses, out of a fleet of 60,000 taxis and 19,000 buses. A new fleet of 3,795 buses powered by natural gas are already on the road.

China actively cutting back now P-R inside`8 (people’s republic inside)6/08http://www.pr-inside.com/china-desulphurization-industry-report-r649414.htm In the recent years, China has been on the top of the world in terms of sulfur dioxide emission, which has surpassed 20 million tons annually for a few years consecutively. Of which, nearly half of the emissions were from coal-fired power plants. During the Tenth Five-Year Plan period (2001-2005), China not only failed to hit its target to cut the emissions by 20%, but also actually increased the emissions by 27%, making the environment protection target the only national economic assessment indicator that China missed. In 2007, the total capacity of contracted projects of desulphurization companies was 374 million kw, of which 208 million kw was put into operation. Limestone-gypsum wet desulphurization was the most widely used method by desulphurization companies. In addition, flue gas desulphurization-based circulating fluidized bed was also used to a certain extent. As the market has experienced full competition, so the competition pattern has basically formed. In addition, localization rate of desulphurization equipment are constantly increasing. Therefore, we believe that although gross profit margin will fall in tandem with the drop in project quotes in the future, the fall won't be big. We predict that the gross profit margin of the industry will hover at the level ranging 15% to 20%. At the end of March of 2007, the National Development and Reform Commission and Ministry of Environment Protection jointly issued the 11th Five-Year Plan for SO2 Pollution Control of Existing Coalfired Power Plants. According to the plan, existing coal-fired power plants will cut their SO2 emission by 61.4% on 2005 basis. In the light with the plan, China's existing coal-fired power plants are required to install flue gas desulphurization units with a total capacity of 137 million kw, covering 221 projects, which will reduce 4.9 million tons of SO2 emission. Along with other measures, such as elimination of outdated production facilities, use of low sulfur content coal, energy-saving and emission reduction, it is forecast that SO2 emission of existing coal-fired power plants will reduce to 5.02 million tons in 2010 from 13 million tons posted in 2005, representing a fall of 61.4 percent. According to Several Opinions Regarding Acceleration of Shutting Down Small Thermal Power Generating Units, newly-built coal-fired generating units must be simultaneously accompanied with the construction of high-efficiency desulphurization and dust removal facilities. Except small thermal power plants to be shut down, power plants with a capacity of 135,000 kw per unit in service should complete the renovation of their desulphurization facilities as soon as possible. Coal-fired generating units, which have installed desulphurization units but have failed to meet emission standards, will not enjoy the favorable tariff for desulphurized generating units. Thermal power industry is the major sources of SO2 emission. The enforcement of the plan will play a decisive role in achieving the binding targets to cut SO2 emission by 10% and improving the quality of atmospheric environment in China.

Gonzaga Debate Institute 2008 Scholars

63 Aerosols

AT: Air Pollution = Disease Air Pollution doesn’t cause disease mortality, there is no connection between the two CO2 Science Magazine 2001 (“SO2, CO, Smoke or Low Temperature: Which Kills More? Review of Keatinge, W.R. and Donaldson, G.C. 2001. Mortality related to cold and air pollution in London after allowance for effects of associated weather patterns. Environmental Research 86”, http://www.co2science.org/scripts/CO2ScienceB2C/articles/V4/N34/C2.jsp The authors studied the effects of temperature, wind, rain, humidity and sunshine during high pollution days in the greater London area over the period 1976-1995 to determine what weather and/or pollution factors have the biggest influence on human mortality. What was learned Simple plots of mortality rate versus daily air temperature revealed a linear increase as temperatures fell from 15°C to near 0°C. Mortality rates at temperatures above 15°C were, in the words of the authors, "grossly alinear," showing no trend. Days with high SO2, CO or PM10 concentrations were colder than average, but a multiple regression analysis revealed that none of these pollutants was associated with a significant increase in mortality among those 50+ years of age. Indeed, only low temperatures were shown to have a significant effect on both immediate (1 day after the temperature perturbation) and long-term (up to 24 days after the temperature perturbation) mortality rates. The net increase in mortality over a 24-day period following a 1-day fall in temperature was 2.77 daily deaths per million people per degree Celsius. Why are cold temperatures so deadly? The authors say it is because "cold causes mortality mainly from arterial thrombosis and respiratory disease, attributable in turn to cold-induced hemoconcentration and hypertension and respiratory infections." What it means Given the large amount of data examined and the types of analyses conducted, the authors conclude they have "confirmed that the large, delayed increase in mortality after low temperature is specifically associated with cold and is not due to associated patterns of wind, rain, humidity, sunshine, SO2, CO, or smoke." Yes, cold kills. Perhaps we should all pray for a little global warming as an antidote.

Gonzaga Debate Institute 2008 Scholars

64 Aerosols

AT: Aerosols = Famine CO2 completely offsets the negative impacts of SO2 on plants, especially food crops CO2 Science Magazine 2001 (“Elevated CO2 Completely Ameliorates SO2 Damage in Soybean: Review of Deepak, S.S. and Agrawal, M. 2001. Influence of elevated CO2 on the sensitivity of two soybean cultivars to sulphur dioxide. Environmental and Experimental Botany 46”, 2001, http://www.co2science.org/scripts/CO2ScienceB2C/articles/V4/N31/B1.jsp) What was learned Exposure to elevated SO2 significantly reduced every growth parameter studied in the two soybean cultivars. Total plant biomass and grain yield, for example, were both reduced by SO2 by approximately 18%, regardless of cultivar. In contrast, elevated CO2 significantly increased every growth parameter in both soybean cultivars. Elevated CO2, for example, increased total plant biomass and grain yield in both cultivars by averages of 30 and 34%, respectively. Moreover, when the plants were exposed simultaneously to elevated CO2 and SO2, the negative effects of SO2 on these growth parameters were completely ameliorated. In fact, their observed values were not significantly different from those obtained under CO2-enriched conditions alone. What it means As the air's CO2 concentration increases, it will likely allow soybean plants to experience less stress and growth reductions from SO2 pollution. In this particular study, for example, SO2-induced growth and yield reductions were completely offset by atmospheric CO2 enrichment. Thus, agricultural fields near industrial areas that have historically produced low soybean yields due to SO2 pollution will likely exhibit increases in yield in response to the ever-increasing CO2 content of the air.

Gonzaga Debate Institute 2008 Scholars

65 Aerosols

AT: Aerosols Not Check Warming / Aerosols Studies The cooling effect of aerosols is balancing 90% of the warming expected from greenhouse gas emissions, the best data and studies support our aerosols argument World Climate Report 2001 (“Smoking Out UN-Science”, World Climate Report, Feb 19, 2001, http://www.worldclimatereport.com/archive/previous_issues/vol6/v6n11/feature1.htm) The upshot of the addition of Jacobson's findings is that the amount of warming we should currently be observing increases. Using the estimates of NASA climatologist James Hansen, if there were no indirect sulfate cooling, and if the oceans weren't holding back warming, the total rise in temperature of the lower atmosphere (the troposphere) should be around 2.3 to 3.3°C by now, with the majority in recent decades. Yet according to surface, satellite and weather balloon records, the observed warming averaged over the troposphere since the three histories became concurrently available (since January 1979), is only around 0.07°C— or about one-tenth of what should have happened. Something has got to give here. The ocean isn't holding back that much—Hansen says he believes about 60 percent of the ultimate warming for today's atmospheric changes should already have been realized. The only way a person can explain the profound difference between observations and projections is to assume that the sulfate cooling effect is massive.

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66 Aerosols

AT: Methodology Problems The latest climate models and large scientific studies conclude that aerosols from fossil fuel consumption are balancing the warming effects of greenhouse gases Dybas 1995 (Cheryl, National Science Foundation, “NSF Scientists to Study Airborne Particles that May Be Cooling Earth”, October 1995, http://www.findarticles.com/p/articles/mi_pfsf/is_199510/ai_1404523332/print) Scientists now suspect that increasing numbers of small particles of sulfur compounds and other pollutants floating in the atmosphere may affect so-called greenhouse warming in heavily industrialized regions. By reflecting sunlight back to space, these tiny airborne particles, called aerosols, can cool the earth beneath. To learn more about "background" aerosols -- the naturally occurring counterparts to these pollutants - researchers from eight universities and the National Science Foundation (NSF)-supported National Center for Atmospheric Research (NCAR) in Boulder, Colorado are flying to the remote skies of Tasmania, with stops in Alaska, Hawaii, and other sites along the way. Flight operations for detailed studies of "clean" ocean air in the Southern Hemisphere will be based at Hobart, Tasmania, and take place from November 15 to December 14, 1995. More than 100 scientists from 57 institutions representing Australia, France, Germany, Italy, Japan, the Netherlands, New Zealand, Sweden, the United Kingdom, and the United States are participating in this major study of airborne particles. "Existing theories suggest that it should be very hard to create new particles in the lower atmosphere, yet they keep showing up," says researcher Barry Huebert of the University of Hawaii at Honolulu. "We're deploying stateof- the-art instruments to the remote marine atmosphere for the first time to seek the source of these new particles. This is the largest and most comprehensive experiment on natural background aerosols that we have ever done." Among the high- tech instrumentation will be NCAR's dualwavelength airborne lidar, which will map the vertical extent of aerosol layers in the atmosphere. Experiments will be conducted from a fully equipped C-130 research airplane owned by NSF and operated by NCAR. Researchers aboard the C-130 will spend as many flight hours taking measurements during the two-week trip from the north Alaska coast to south of New Zealand as they will during the operations in Tasmania. In Alaska, they will begin their research measurements with a flight toward the North Pole and back. While in Hawaii November 5 and 6, the C-130 will fly through the Kilauea volcano plume to study how its particles form and how much sunlight they reflect. After arrival at Hobart, a flight toward the South Pole will complete the study's nearly pole-to-pole measurements. Called ACE-1, the study is the first of the Aerosol Characterization Experiments, a series of international field programs to help scientists understand the chemical, physical, and optical properties of aerosols; how they form and grow; and their effect on radiation and climate. Like carbon dioxide, sulfate aerosols are produced by human activity, mainly the burning of fossil fuels. They also exist naturally as sulfur emissions from living organisms and volcanoes. By scattering incoming solar energy back to space, both the natural and pollutant aerosols directly affect the amount of radiation entering the earth's atmosphere. They also serve as tiny sites on which water vapor can condense, allowing more small droplets to form within a cloud. This change in the droplets' size distribution makes the cloud more reflective, bouncing more solar radiation back to space and cooling the earth below. In ACE-1, scientists will study the natural marine system -distant from Northern Hemisphere sulfate aerosols produced by human activity. ACE-2, scheduled for 1997, will focus on the marine atmosphere near European industrialized areas. As scientists learn more about aerosols naturally occurring in the undisturbed atmosphere, they can better assess the growing influence of humanproduced sulfate aerosols on climate. "Until recently all climate models have supposed that the only human activity driving climate change was the production of carbon dioxide and other greenhouse gases," explains scientist Tom Wigley of NCAR. "We now believe that other factors, particularly sulfate aerosols, may be as important as greenhouse gases."

Gonzaga Debate Institute 2008 Scholars

67 Aerosols

AT: Only Delay Impacts We only need to delay warming, synthetic aerosols can be used to produce long term dimming The Age`8( The Age, European Based World news network, Flannery proposes 'global dimming' to save planet, May 19 2008, http://www.theage.com.au/news/global-warming/radical-plan-to-save-planet/2008/05/19/1211182701986.html)

Scientist Tim Flannery has proposed a radical solution to climate change which may change the colour of the sky. But he says it may be necessary, as the "last barrier to climate collapse." Professor Flannery says climate change is happening so quickly that mankind may need to pump sulphur into the atmosphere to survive. Australia's best-known expert on global warming has updated his climate forecast for the world - and it's much worse than he thought just three years ago. He has called for a radical suite of emergency measures to be put in place. The gas sulphur could be inserted into the earth's stratosphere to keep out the sun's rays and slow global warming, a process called global dimming. "It would change the colour of the sky," Professor Flannery told AAP. "It's the last resort that we have, it's the last barrier to a climate collapse." "We need to be ready to start doing it in perhaps five years time if we fail to achieve what we're trying to achieve." Professor Flannery, the 2007 Australian of the Year, said the sulphur could be dispersed above the earth's surface by adding it to jet fuel.

Climate engineering projects will solve warming in the long run, and prove the validity of aerosols as a counterbalance to greenhouse gases, we just need to delay warming to survive Connor 2006 (Steve, Science Editor of The Independent (London), “Scientist publishes escape route from global warming”, Belfast Telegraph, July 31, 2006) His plan is modelled partly on the Mount Pinatubo volcanic eruption in 1991, when thousands of tons of sulphur were ejected into the atmosphere causing global temperatures to fall. Pinatubo generated sulphate aerosols in the atmosphere which cooled the Earth by 0.5C on average in the following year. The sulphate particles did this by acting like tiny mirrors, preventing a portion of incoming sunlight from reaching the ground. Professor Crutzen calculated that a relatively small amount of sulphur could cause similar cooling if it was released at high enough altitudes into the stratosphere, rather than at the lower altitude of the troposphere. Weather balloons or even artillery shells could be used to carry the sulphur. Although climate cooling by sulphate aerosols also occurs in the troposphere, the great advantage of placing reflective particles in the stratosphere is their long residence time of about one to two years, compared to a week in the troposphere, Professor Crutzen said. It may be possible to manufacture a special gas that is only processed photochemically in the stratosphere to yield sulphate, he said. Such a compound should be non-toxic, insoluble in water, non-reactive, and have a relatively short half-life of about 10 years. It would cost between $25bn and $50bn or about $25 or $50 per head in the developed world to launch sufficient sulphate to last for up to two years. But this high cost should be measured against the much bigger costs of environmental disasters, such as coastal flooding, caused by global warming, he said. Side-effects could be an increase in the destruction of the ozone layer and whitening of the sky, although the particles would make sunsets and sunrises more spectacular, he said. Other geo-engineering ideas Reflecting mirrors: Earth s natural reflectance or albedo reflects about 30 per cent of sunlight back into space. Increasing the albedo could be done by building giant unfolding mirrors in space, laying reflecting film in the deserts, or floating white plastic islands in the ocean to mimic reflective effect of sea ice. Swallowing up CO2: Marine plankton absorb carbon dioxide from the atmosphere, which the microbes need for photosynthesis. The growth of plankton is limited by the relatively small amounts of iron in the sea. Scientists have conducted experiments on boosting plankton by throwing iron filings into the sea.

Gonzaga Debate Institute 2008 Scholars

***DIMMING / SO2 BAD

68 Aerosols

Gonzaga Debate Institute 2008 Scholars

69 Aerosols

SO2/Dimming Low Now [1/2] Dimming low now-Clean air policies Carbon Footprint`8 (Carbon foot print.com, “Global Dimming” June 27, 2008, http://www.carbonfootprint.com/dimming.html)

Does Global Dimming counteract Global warming? Global Dimming can, and actually has, slowed the effects of Global Warming. However, the Earth's population is now doing something about the amount of carbon particulates being released in to the atmosphere, by fitting catalytic converters to cars and reducing emissions from power stations etc. Many scientists now believe that the rate of global warming has been significantly underestimated because of global dimming, and global warming will accelerate giving us even less time than originally thought to take action.

The age of dimming is over NASA`7 (National Aeronautics and Space Administration, Global 'Sunscreen' Has Likely Thinned, Report NASA Scientists, 03.15.07, http://www.nasa.gov/centers/goddard/news/topstory/2007/aerosol_dimming.html)

A new NASA study has found that an important counter-balance to the warming of our planet by greenhouse gases – sunlight blocked by dust, pollution and other aerosol particles – appears to have lost ground. Image above: The average amount of dust, pollution and other aerosol particles in the atmosphere has dropped since the 1990s. Global averages were relatively low in the period 2002 to 2005, shown here (highest aerosol levels in light blue, lowest in purple). Credit: NASA Global Aerosol Climatology Project The thinning of Earth’s “sunscreen” of aerosols since the early 1990s could have given an extra push to the rise in global surface temperatures. The finding, published in the March 16 issue of Science, may lead to an improved understanding of recent climate change. In a related study published last week, scientists found that the opposing forces of global warming and the cooling from aerosol-induced "global dimming" can occur at the same time. "When more sunlight can get through the atmosphere and warm Earth's surface, you're going to have an effect on climate and temperature," said lead author Michael Mishchenko of NASA's Goddard Institute for Space Studies (GISS), New York. "Knowing what aerosols are doing globally gives us an important missing piece of the big picture of the forces at work on climate." The study uses the longest uninterrupted satellite record of aerosols in the lower atmosphere, a unique set of global estimates funded by NASA. Scientists at GISS created the Global Aerosol Climatology Project by extracting a clear aerosol signal from satellite measurements originally designed to observe clouds and weather systems that date back to 1978. The resulting data show large, short-lived spikes in global aerosols caused by major volcanic eruptions in 1982 and 1991, but a gradual decline since about 1990. By 2005, global aerosols had dropped as much as 20 percent from the relatively stable level between 1986 and 1991. Image above: Sun-blocking aerosols around the world steadily declined (red line) since the 1991 eruption of Mount Pinatubo, according to satellite estimates. The decline appears to have brought an end to the "global dimming" earlier in the century. Credit: Michael Mishchenko, NASA The NASA study also sheds light on the puzzling observations by other scientists that the amount of sunlight reaching Earth's surface, which had been steadily declining in recent decades, suddenly started to rebound around 1990. This switch from a "global dimming" trend to a "brightening" trend happened just as global aerosol levels started to decline, Mishchenko said. While the Science paper does not prove that aerosols are behind the recent dimming and brightening trends -- changes in cloud cover have not been ruled out -- another new research result supports that conclusion In a paper published March 8 in the American Geophysical Union's Geophysical Research Letters, a research team led by Anastasia Romanou of Columbia University's Department of Applied Physics and Mathematics, New York, also showed that the apparently opposing forces of global warming and global dimming can occur at the same time.

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70 Aerosols

SO2/Dimming Low Now [2/3] Dimming hasn’t been relevant since the 80’s Wild et al. 2007 (Wild, M., A. Ohmura, and K. Makowski (2007), Impact of global dimming and brightening on global warming, Geophys. Res. Let http://www.agu.org/pubs/crossref/2007/2006GL028031.shtml)

Speculations on the impact of variations in surface solar radiation on global warming range from concerns that solar dimming has largely masked the full magnitude of greenhouse warming, to claims that the recent reversal from solar dimming to brightening rather than the greenhouse effect was responsible for the observed warming. To disentangle surface solar and greenhouse influences on global warming, trends in diurnal temperature range are analyzed. They suggest that solar dimming was effective in masking greenhouse warming, but only up to the 1980s, when dimming gradually transformed into brightening. Since then, the uncovered greenhouse effect has revealed its full dimension, as manifested in a rapid temperature rise (+0.38°C/decade over land since mid1980s). Recent solar brightening cannot supersede the greenhouse effect as main cause of global warming, since land temperatures increased by 0.8°C from 1960 to 2000, even though solar brightening did not fully outweigh solar dimming within this period.

US SO2 emissions dropping Ludwig`4Lindsay C. Ludwig, 10/04 http://org.elon.edu/ipe/Ludwig_Edited.pdf In our world of rapid industrialization and scarce natural resources it is imperative that the United States and other countries find a cost-effective way to reduce pollution. For years the most prevalent means of pollution control were command-and-control reduction methods. Command-and-control methods rely on government bureaucrats to set pollution standards and then enforce them through the use of monetary fines. Beginning in the late 1960’s the thought of using economic incentives to control pollution levels started to emerge and by 1975 the first permit trading programs had begun (Tietenberg, 1). Permit trading programs work by allowing pollution sources that decrease discharges more than the set standard to amass pollution permits. Other firms that cannot meet standards can then buy up these permits. In theory incentive based programs are said to be better than traditional command-and-control programs because they are more cost-effective in the short-run, increase incentives to seek out new technology in the long-run, reduce the costly burden of information gathering for regulatory bureaucrats, and are more flexible. On the other hand, there have been some criticisms of these new programs, one of which is that permit trading will lead to condensed areas of pollution known as “hot-spots” (Goodstein 2002, 300) As part of the Clean Air Act Amendments of 1990 the United States enacted The Acid Rain Program to achieve a decrease in sulfur dioxide (SO2) and nitrogen oxides (NOx), which are the leading causes of acid rain. This study will focus on the program’s regulation of SO2 emissions. The area of this program dealing with SO2 is compromised of two phases; Phase I began in 1995 and focused on decreasing the emissions from the 110 most polluting sources, Phase II began in 2000 and further limited emissions from all large sources as well as any new sources. The program works by distributing pollution permits among the firms based on historical pollution levels. Unused permits may be sold, traded, or banked for future use. Sources that pollute in excess of the permits they hold are penalized. So far the Acid Rain Program has been very successful and is well on the way to meeting its goal emission level of 8.95 million tons by 2010— a 50% reduction from 1980 levels (EPA b 2002, 1-3) (see Figure 1, notice the drop in emissions at the start of the Acid Rain Program in 1995). Although this program has been successful, the problem of pollution hot-spots has not been adequately addressed and still may be a very real threat.

Gonzaga Debate Institute 2008 Scholars

71 Aerosols

SO2/Dimming Low Now [3/3] We’re now in an age of global brightening-Cleaner standards and USSR collapse reduced pollutants Leake`6 (Jonathan, Science editor for the London Times, Brighter sun adds to fears of climate change, March 26, 2006, Lexis.)

THE amount of sunshine reaching earth is increasing, accelerating the pace of climate change, scientists have found. A series of independent studies around the world show a significant rise in the amount of sunshine penetrating the atmosphere to be absorbed by the earth's surface and turned into heat. The research will concern climate researchers who are already predicting a rapid rise in global temperatures due to man-made emissions of so-called greenhouse gases such as carbon dioxide. "The enhanced warming we have seen since the 1990s along with phenomena such as the widespread melting of glaciers could well be due to this increased intensity of sunlight compounding the effect of greenhouse gases," said Professor Martin Wild of the Institute of Atmospheric and Climate Science in Zurich, Switzerland. Researchers will present their findings to the European Geophysical Union conference in Vienna next week. They reverse a 30-year trend. Measurements of sunshine levels between 1960 and 1990 had shown a decrease in the amount of sunshine reaching the earth, a phenomenon known as global dimming. This was thought to have been caused by dust, smog and other pollutants, mainly from industrialised western countries. The pollutants, known as aerosols, reduced sunshine levels by absorbing and scattering solar radiation and promoting the formation of clouds that reflected radiation back into space. In the last two decades, however, there have been significant decreases in such pollutants, partly due to industry becoming cleaner but largely because of the collapse of the Soviet Union and much of its heavy industry. Wild said: "Sunshine levels had been decreasing by 2% a decade between 1960 and 1980 -a total decline of about 6%. Now they are going up again. Perhaps this is why our Swiss glaciers are melting." A 6% increase in the amount of solar radiation reaching earth would have a powerful impact on climate, especially when added to the warming effect of greenhouse gases which have already raised global temperatures by about 0.6C. Researchers predict an additional rise of at least 1.5C by 2050. Such rises could be disastrous for agriculture, wildlife and human settlements in many regions, especially the tropics. But scientists warn they may have to revise these calculations sharply upwards if the impact of "global brightening" has to be factored in. Atsumu Ohmura, of the Swiss Federal Institute of Technology in Zurich, has collated measurements from 400 sites worldwide and found an increase in sunshine at 300 of them, sited mainly in Eurasia and the Polar regions. Some showed a decline in sunshine since 1990, largely in fast-developing countries such as China and India. "A widespread brightening has been observed since the 1980s. This may substantially affect surface climate, the water cycle, glaciers and ecosystems," said Ohmura.

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Aerosols/FF’s = Acid Rain Aerosols = Acid Rain Reid & Roberts`2 (Reid, Jonathan P. ; Sayer, Robert M., Chemistry in the clouds: the role of aerosols in atmospheric chemistry., Science Progress, 22-SEP-02 http://goliath.ecnext.com/coms2/gi_0199-2205436/Chemistry-in-the-cloudsthe.html)

Sulphuric ([H.sub.2][SO.sub.4]) and nitric ([HNO.sub.3]) acids are primarily responsible for the phenomenon of acid rain. These acids can be produced by oxidation of the oxides of sulphur and nitrogen. Chemistry on atmospheric aerosols plays a significant role in such processes. (9,10) The principal source of sulphuric acid is the oxidation of sulphur dioxide. This can occur in the homogeneous gas phase, on aerosol particles and by oxidation at the earth's surface. S[O.sub.2] is removed from the atmosphere by wet and dry deposition at a more rapid rate than homogeneous oxidation can occur. This, combined with evidence that oxidation rates are higher under conditions of high humidity or when condensed water is available, suggests that oxidation mediated by aerosol particles is a dominating pathway for sulphuric acid generation. (4) The effects of acid rain were recognised as early as the middle of the 1950s and a link to the combustion of fossil fuels was established. Atmospheric water has a pH of ~5.6 due to dissolved carbon dioxide and the formation of the weak acid, carbonic acid. In clean unpolluted air, the background natural concentrations of S[O.sub.2] and nitrogen oxides can lead to cloud droplet pHs as low as 5. Anthropogenic pollution, principally from fossil fuel combustion, dominates the level of S[O.sub.2] in the atmosphere with the global man-made emissions being approximately ten times larger than the natural emissions. (11) In the areas most affected by acid rain, such as the north-eastern United States and in Scandinavian countries, typical pHs of precipitation water are around 4, but pHs as acidic as 2.1 have been observed. (12)

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SO2=Acidic Oceans SO2 substantially increases oceanic acidity WHOI`8 (Woods Hole Oceanographic Institute) 6/22/08 http://www.whoi.edu/oceanus/viewArticle.do?id=40671§ionid=1021

The release of sulfur and nitrogen into the atmosphere by power plants and agricultural activities plays a minor role in making the ocean more acidic on a global scale, but the impact is greatly amplified in the shallower waters of the coastal ocean, according to new research by atmospheric and marine chemists. Ocean “acidification” occurs when chemical compounds such as carbon dioxide, sulfur, or nitrogen mix with seawater, a process which lowers the pH and reduces the storage of carbon. Ocean acidification hampers the ability of marine organisms—such as sea urchins, corals, and certain types of plankton—to harness calcium carbonate for making hard outer shells or “exoskeletons.” These organisms provide essential food and habitat to other species, so their demise could affect entire ocean ecosystems. The findings were published this week in the online “early edition” of the Proceedings of the National Academy of Sciences; a printed version will be issued later this month. “Acid rain isn’t just a problem of the land; it’s also affecting the ocean,” said Scott Doney, lead author of the study and a senior scientist in the Department of Marine Chemistry and Geochemistry at the Woods Hole Oceanographic Institution (WHOI). “That effect is most pronounced near the coasts, which are already some of the most heavily affected and vulnerable parts of the ocean due to pollution, over-fishing, and climate change.” In addition to acidification, excess nitrogen inputs from the atmosphere promote increased growth of phytoplankton and other marine plants which, in turn, may cause more frequent harmful algal blooms and eutrophication (the creation of oxygen-depleted “dead zones”) in some parts of the ocean. Doney collaborated on the project with Natalie Mahowald, Jean-Francois Lamarque, and Phil Rasch of the National Center for Atmospheric Research, Richard Feely of the Pacific Marine Environmental Laboratory, Fred Mackenzie of the University of Hawaii, and Ivan Lima of the WHOI Marine Chemistry and Geochemistry Department. “Most studies have traditionally focused only on fossil fuel emissions and the role of carbon dioxide in ocean acidification, which is certainly the dominant issue,” Doney said. “But no one has really addressed the role of acid rain and nitrogen.” The research team compiled and analyzed many publicly available data sets on fossil fuel emissions, agricultural, and other atmospheric emissions. They built theoretical and computational models of the ocean and atmosphere to simulate where the nitrogen and sulfur emissions were likely to have the most impact. They also compared their model results with field observations made by other scientists in the coastal waters around the United States. Farming, livestock husbandry, and the combustion of fossil fuels cause excess sulfur dioxide, ammonia, and nitrogen oxides to be released to the atmosphere, where they are transformed into nitric acid and sulfuric acid. Though much of that acid is deposited on land (since it does not remain in the air for long), some of it can be carried in the air all the way to the coastal ocean. When nitrogen and sulfur compounds from the atmosphere are mixed into coastal waters, the researchers found, the change in water chemistry was as much as 10 to 50 percent of the total changes caused by acidification from carbon dioxide. This rain of chemicals changes the chemistry of seawater, with the increase in acidic compounds lowering the pH of the water while reducing the capacity of the upper ocean to store carbon. The most heavily affected areas tend to be downwind of power plants (particularly coal-fired plants) and predominantly on the eastern edges of North America, Europe, and south and east of Asia. Seawater is slightly basic (pH usually between 7.5 and 8.4), but the ocean surface is already 0.1 pH units lower than it was before the Industrial Revolution. Previous research by Doney and others has suggested that the ocean will become another 0.3 to 0.4 pH units lower by the end of the century, which translates to a 100 to 150 percent increase in acidity. Funding for this research was provided by the National Science Foundation, the National Aeronautics and Space Administration, and the National Oceanic and Atmospheric Administration. Woods Hole Oceanographic Institution is a private, independent organization in Falmouth, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the oceans and their interaction with the Earth as a whole, and to communicate a basic understanding of the ocean's role in the changing global environment.

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Acid Rain hurts oceans [1/2] Acidic oceans threaten marine life Highfield`7 (Science Editor for the UK telegraph 10/07 http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/10/17/sciocean117.xml )

Concerns that sea life will struggle for survival as greenhouse gases make the oceans more acidic are amplified today by a study that shows that marine creatures such as snails and crabs will have weakened defences to protect them against predators. Leaving aside the direct effects of greenhouse gases on climate change, the oceans "mop up" carbon dioxide from the atmosphere so that levels of carbonic acid rise. There are fears that the resulting rise in acidity could particularly affect sea creatures with hard shells because it cuts the availability of calcium carbonate (chalk) - which coral reefs, clams, molluscs and some plankton use to produce their hard skeletons. The acidity of the seas is having a damaging effect on the hard shells of marine creatures like crabs Now it seems that the rise in the acidity of the seas has another effect on shellfish. Many marine creatures, from crabs and lobsters to molluscs, are able to protect themselves from predators by growing thicker shells when they are under greater threat. Today, in the journal Biology Letters, Dr Simon Rundle of the University of Plymouth and colleagues there and at the Plymouth Marine Laboratory report that this common ability is disrupted in the case of the common periwinkle, which thickens its shell in the presence of predatory shore crabs. "This thickening was absent when snails grew in acidified seawater; these snails also had disrupted physiologies and behaviour." Although the experiments were performed under laboratory conditions that aimed to mimic extreme future acidification scenario "they do suggest, however, that effects of seawater acidification are likely to be more extensive than previously thought and extent beyond direct effects," said Dr Rundle. "The effects will be even more pronounced." If this is common, it could alter the way marine food webs work, he added. One recent study from California State University found that half of the carbon emitted by human activities over the last two centuries has entered the oceans. Another, by the US Livermore National Laboratory, predicts that the release of carbon dioxide during the next several centuries will increase ocean acidity more rapidly than during the past 300 million years, except perhaps during global catastrophes. Increased acidity may also directly affect the growth and reproduction rates of fish, as well as affecting the plankton populations which they rely on for food, and have potentially disastrous consequences for marine food webs. Acid rain depletes marine life

Kintisch`7 Eli 12/07 http://discovermagazine.com/2008/jan/acid-rain-intensifies-threat-to-marine-life Human-generated carbon dioxide in the atmosphere is slowly acidifying the ocean, threatening a catastrophic impact on marine life. And just as scientists are starting to grasp the magnitude of the problem, researchers have delivered more bad news: Acid rain is making things worse. Scientists estimate that one-third of the world’s acid rain falls near the coasts, carrying some 100 million tons of nitrogen oxide, ammonia, and sulfur dioxide into the ocean each year. Using direct measurements and computer models, oceanographer Scott Doney of Woods Hole Oceanographic Institution and his colleagues calculated that acid rain causes as much as 50 percent of the acidification of coastal waters, where the pH can be as low as 7.6. (The open ocean’s pH is 8.1.) The findings increase the urgency of confronting the crisis of ocean acidity, says Richard Feely, a collaborator at the National Oceanic and Atmospheric Administration. In the laboratory, researchers have seen some effect on just about every ocean creature that forms a calcium carbonate shell, says Feely, including algae—the tiny creatures at the crucial bottom of the deepwater food chain—and coral, whose skeletons grow more slowly in water with a pH even slightly lower than normal. Soon-to-be-released field experiment findings “seem to be showing the same kind of thing,” Feely says. That’s bad news, he adds, since a third of the world’s fish species depend in part on coral reefs for their ecosystems.

SO2 hurts ocean ecosystems-Acid Rain WHOI`7 (Woods Hole Oceanographic Institute, 9/07 http://www.whoi.edu/oceanus/viewArticle.do?id=40671§ionid=1021)

Acid rain isn’t just a problem of the land; it’s also affecting the ocean,” said Scott Doney, a marine chemist at Woods Hole Oceanographic Institution (WHOI) and lead author of the study. “That effect is most pronounced near the coasts, which are already some of the most heavily affected and vulnerable parts of the ocean due to

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Acid Rain hurts oceans [2/2] pollution, overfishing, and climate change.” Farming, livestock husbandry, and the combustion of fossil fuels releases excess sulfur dioxide, ammonia, and nitrogen oxides to the atmos-phere, where they are transformed into nitric acid and sulfuric acid. A portion of these compounds is blown offshore, where they enter the ocean and alter its chemistry. The acids lower seawater’s pH and strip it of carbonate ions. (Ultimately, so does ammonia, a base, which is converted to nitrates and nitric acid.) That hampers the ability of marine organisms— such as sea urchins, shellfish, corals, and certain types of plankton—to harness calcium carbonate to make hard outer shells or “exoskeletons.” These organisms provide essential food and habitat to other species, so their demise could affect entire ocean ecosystems. Ocean acidification is already a concern because excess carbon dioxide from fossil fuels produces the same effects. Though carbon dioxide remains the dominating factor, “no one has really addressed the role of acid rain and nitrogen,” Doney said. Doney collaborated on the project with Natalie Mahowald, Jean-FranÇois Lamarque, and Phil Rasch of the National Center for Atmos-pheric Research, Richard Feely of the Pacific Marine Environmental Laboratory, Fred Mackenzie of the University of Hawaii, and Ivan Lima of WHOI. The research team analyzed data on agricultural, fossil fuel and other atmospheric emissions. They built theoretical and computational models of the ocean and atmosphere to simulate where the nitrogen and sulfur emissions were likely to have the most impact. Then they ground-truthed their model’s results with field observations in coastal waters by other scientists. The most heavily affected areas tend to be downwind of eastern North America, western Europe, and east and south Asia.

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Acid Rain - Ocean destruction=Extinction Oceans destruction=Extinction CBS`6 (CBS, Salt-Water Fish Extinction Seen By 2048 Study By Ecologists, Economists Predicts Collapse of World Ocean EcologyNov. 3, 2006, http://www.cbsnews.com/stories/2006/11/02/health/webmd/main2147223.shtml)

The apocalypse has a new date: 2048. That's when the world's oceans will be empty of fish, predicts an international team of ecologists and economists. The cause: the disappearance of species due to overfishing, pollution, habitat loss, and climate change. The study by Boris Worm, PhD, of Dalhousie University in Halifax, Nova Scotia, -- with colleagues in the U.K., U.S., Sweden, and Panama -- was an effort to understand what this loss of ocean species might mean to the world. The researchers analyzed several different kinds of data. Even to these ecology-minded scientists, the results were an unpleasant surprise. "I was shocked and disturbed by how consistent these trends are -- beyond anything we suspected," Worm says in a news release. "This isn't predicted to happen. This is happening now," study researcher Nicola Beaumont, PhD, of the Plymouth Marine Laboratory, U.K., says in a news release. "If biodiversity continues to decline, the marine environment will not be able to sustain our way of life. Indeed, it may not be able to sustain our lives at all," Beaumont adds. Already, 29% of edible fish and seafood species have declined by 90% -- a drop that means the collapse of these fisheries. But the issue isn't just having seafood on our plates. Ocean species filter toxins from the water. They protect shorelines. And they reduce the risks of algae blooms such as the red tide. "A large and increasing proportion of our population lives close to the coast; thus the loss of services such as flood control and waste detoxification can have disastrous consequences," Worm and colleagues say. The researchers analyzed data from 32 experiments on different marine environments. They then analyzed the 1,000-year history of 12 coastal regions around the world, including San Francisco and Chesapeake bays in the U.S., and the Adriatic, Baltic, and North seas in Europe. Next, they analyzed fishery data from 64 large marine ecosystems. And finally, they looked at the recovery of 48 protected ocean areas. Their bottom line: Everything that lives in the ocean is important. The diversity of ocean life is the key to its survival. The areas of the ocean with the most different kinds of life are the healthiest. But the loss of species isn't gradual. It's happening fast -- and getting faster, the researchers say. Worm and colleagues call for sustainable fisheries management, pollution control, habitat maintenance, and the creation of more ocean reserves. This, they say, isn't a cost; it's an investment that will pay off in lower insurance costs, a sustainable fish industry, fewer natural disasters, human health, and more. "It's not too late. We can turn this around," Worm says. "But less than 1% of the global ocean is effectively protected right now.".

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Acid Rain-Kills Coral [1/2] Acidic oceans destroy coral ecosystems Asian News International`8 June 9 http://www.dailyindia.com/show/247908.php/ Acidic-oceans-may-spell-doom-for-coral-ecosystems-by-2100 In a new research, scientists have warned that as oceans become more acidic by the year 2100, coral ecosystems may start to vanish because of an invasion of opportunistic marine species like algae and mollusks, who are better able to survive in the new environment. According to a report in New Scientist, an exploration of natural "bubble streams" of carbon dioxide (CO2) in shallow Mediterranean waters off the coast of Italy is the first to document the effects of ocean acidification in a real ocean setting. It is well understood that oceans will become more acidic as CO2 concentrations rise is well understood. By the year 2100, ocean acidity is predicted to be 7.8 pH, compared to 8.2 pH in 1900. But all the studies of how this will affect marine ecosystems have been carried out in laboratories, many involving organisms with shells being placed in low-pH seawater and watching them slowly dissolve. The experiments give little indication of the degree to which this would happen in the open oceans, affected by currents and the population dynamics which regulate ecosystems. Now, Jason Hall-Spencer and colleagues at the University of Plymouth, UK, have looked at just this process. They found a site off the island of Ischia in southern Italy where geologic CO2 naturally seeps through the seafloor. The Ischia site offers an usual opportunity to study cool, acidified ecosystems that are not modified by the toxic effects of sulphur. It also allowed the researchers to study how the Mediterranean ecosystem changed across a pH gradient. On its outer edges, the pH was a "normal" 8.2; in water immediately above the seep, it dropped to 7.4. At a pH of 7.8, the team noticed a marked change. Populations of coralline algae, which hold reefs together, suddenly crashed. Sea-urchins also disappeared. Also, there was a transition from a coral ecosystem to one dominated by lush sea grasses. These, along with invasive algae originally from Asia, thrived in the acidic waters.The researchers warn that as waters become more acidic, opportunistic invasive species that are better able to survive at low pH could move in. Another marked effect of the acidified water was something that has been described in laboratory settings - the hard shells of animals such as limpets softened. "They were paper-thin. You could push your thumb through them," said Hall-Spencer. According to Hall-Spencer, the ecosystem changes he and his colleagues documented in Ischia are relevant to other ocean ecosystems because the types of organisms they studied - sea urchins, corals and sea-grasses - are found around the world.

Increasing Acidity in the world’s Oceans lead to a deterioration of the food chain Washington Post`6 http://www.washingtonpost.com/wpdyn/content/article/2006/07/04/AR2006070400772.html, 7/6 "It's just been an absolute time bomb that's gone off both in the scientific community and, ultimately, in our public policymaking," said Rep. Jay Inslee (D-Wash.), who received a two-hour briefing on the subject in May with five other House members. "It's another example of when you put gigatons of carbon dioxide into the atmosphere, you have these results none of us would have predicted." Thomas E. Lovejoy, president of the H. John Heinz III Center for Science, Economics and the Environment, has just rewritten the paperback edition of "Climate Change and Biodiversity," his latest book, to highlight the threat of ocean acidification. "It's the single most profound environmental change I've learned about in my entire career," he said last week. A coalition of federal and university scientists is to issue a report today describing how carbon dioxide emissions are, in the words of a press release from the National Center for Atmospheric Research and the National Oceanic and Atmospheric Administration, "dramatically altering ocean chemistry and threatening corals and other marine organisms that secrete skeletal structures." For decades, scientists have viewed the oceans' absorption of carbon dioxide as an environmental plus, because it mitigates the effects of global warming. But by taking up one-third of the atmosphere's carbon dioxide -- much of which stems from exhaust from automobiles, power plants and other industrial sources -- oceans are transforming their pH level.

The pH level, measured in "units," is a calculation of the balance of a liquid's acidity and its alkalinity. The lower a liquid's pH number, the higher its acidity; the higher the number, the more alkaline it is. The ph level for the world's oceans was stable between 1000 and 1800, but has dropped one-tenth of a unit since the Industrial Revolution, according to Christopher Langdon, a University of Miami marine biology professor. Scientists expect ocean pH levels to drop by another 0.3 units by 2100, which could seriously damage marine creatures that need calcium carbonate to build their shells and skeletons.

Once absorbed in seawater, carbon dioxide forms carbonic acid and lowers ocean pH, making it harder for corals, plankton and tiny marine snails (called pteropods) to form their body parts. Ken Caldeira, a chemical oceanographer at Stanford University who briefed lawmakers along with NCAR marine ecologist Joan Kleypas, said oceans are more acidic than they have has been for "many millions of years." "What we're doing in the next decade will affect our oceans for millions of years," Caldeira said. "CO2levels are going up extremely rapidly, and it's overwhelming our marine systems." Some have questioned global-warming predictions

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Acid Rain-Kills Coral [2/2] [CONTINUES FROM ABOVE, NO TEXT DELETED] based on computer models, but ocean acidification is less controversial because it involves basic chemistry. "You can duplicate this phenomenon by blowing into a straw in a glass of water and changing the water's pH level," Lovejoy said. "It's basically undeniable." Hugo A. Lo?iciga, a geography professor at the University of California at Santa Barbara, is one of the few academics to question the phenomenon. A groundwater hydrologist, Lo?iciga published a paper in the May edition of the American Geophysical Union's journal that suggested the oceans may not become so acidic, because enough carbonate material will help restore equilibrium to them. Lo?iciga wrote that although seawater in certain regions may become more acidic over time, "on a global scale and over the time scales considered (hundreds of years), there would not be accentuated changes in either seawater salinity or acidity from the rising concentration of atmospheric CO2." Two dozen scientists have written a response questioning this assumption, since it would take thousands of years for such material to reach the oceans from land. "The paper by Lo?iciga ignores decades of scholarship, presents inappropriate calculations and draws erroneous conclusions

unless carbon dioxide levels in the atmosphere stabilize soon, the seas will soon exceed the Environmental Protection Agency's recommended acidity limits. Scientists have conducted a few ocean acidification experiments in recent years. All have shown that adding carbon dioxide to the water slows corals' growth rate and can dissolve pteropods' shells. Langdon, who conducted an experiment between 1996 and 2003 in Columbia University's Biosphere 2 lab in Tucson, concluded that corals grew half as fast in aquariums when exposed to the level of carbon dioxide projected to exist by 2050. Coupled with the higher sea temperatures that climate change produces, Langdon said, corals may not survive by the end of the century. "It's going to be on a global scale and it's that simply do not apply to real ocean," they wrote. They added that,

also chronic," Langdon said of ocean acidification. "Twenty-four/seven, it's going to be stressing these organisms. . . . These organisms probably don't have the adaptive ability to respond to this new onslaught." Stanford University marine biologist Robert B. Dunbar has studied the effect of increased carbon dioxide on coral reefs in Israel and Australia's Great Barrier Reef. "What

we found in Israel was the community is dissolving," Dunbar said. Caldeira has mapped out where corals exist today and the pH levels of the water in which they thrive; by the end of the century, no seawater will be as alkaline as where they live now. If carbon dioxide emissions continue at their current levels, he said, "It's say goodbye' to coral reefs." Although the fate of plankton and marine snails may not seem as compelling as vibrantly colored coral reefs, they are critical to sustaining marine species such as salmon, redfish, mackerel and baleen whales. "These are groups everyone depends on, and if their numbers go down there are going to be reverberations throughout the food chain," said John Guinotte, a marine biologist at the Marine Conservation Biology Institute. "When I see marine snails' shells dissolving while they're alive, that's spooky to me." Rep. Rush D. Holt (DN.J.), a scientist by training, attended the congressional briefing on ocean acidification. He said these developments are "new to me, which was surprising because I

changes in our climate are severe and urgent even if it weren't for this, but this just adds impact and urgency to the situation," Holt said. usually keep up with things." "The

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Acid Rain-Coral k2 Bio-D Coral reefs key to bio-d

B) That’s key to stop extinction Diner`94 (David, JD Ohio State, Military Law Review, Winter, 1994) 4. Biological Diversity. -- The main premise of species preservation is better than simplicity. As the current mass extinction has progressed, the world's biological diversity generally has decreased. This trend occurs within ecosystems by reducing the number of species, and within species by reducing the number of individuals. Both trends carry serious future implications. Biologically diverse ecosystems are characterized by a large number of specialist species, filling narrow ecological niches. These ecosystems inherently are more stable than less diverse systems. "The more complex the ecosystem, the more successfully it can resist stress... [l]ike a net, in which each knot is connected to others by several strands, such a fabric can resist collapse better than a simple, unbranched circle of threads -- which is cut anywhere breaks down as a whole." By causing widespread extinctions, humans have artificially simplified many ecosystems. As biologic simplicity increases, so does the risk of ecosystem failure. The spreading Sahara Desert in Africa, and the dustbowl conditions of the 1930s in the United States are relatively mild examples of what might be expected if this trend continues. Theoretically, each new animal or plant extinction, with all its dimly perceived and intertwined affects, could cause total ecosystem collapse and human extinction. Each new extinction increases the risk of disaster. Like a mechanic removing, one by one, the rivets from an aircraft's wing, mankind may be edging closer to the abyss.

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Acid Rain-Destroys Forest Acid Rain destroys trees in Northeastern US CNN`1 3/26/01 http://archives.cnn.com/2001/TECH/science/03/26/acid.rain.report/index.html WOODSTOCK, New Hampshire (CNN) -- A new study on acid rain concludes that, while some affected areas have seen improvement, the impact of emissions may be much more complicated than previously understood. The study, led by Charles Driscoll of Syracuse University, found that despite major progress in decreasing U.S. emissions of acid rain-producing chemicals, 40 percent of the lakes and streams in New England and upstate New York continue to occasionally post acidity levels that harm plant and animal life. Fifteen percent of those waterways still have chronically high acid levels. Acid precipitation -- carried to earth in rainfall, snow, or fog -- is a byproduct of the burning of fossil fuels. Airborne compounds like sulfur dioxide and nitrogen oxides alter the chemical balance of soils and waterways, turning them from chemically neutral to acidic. In the United States, the Clean Air Act has tightened the rules on acid rain-related emissions -now roughly 62 percent of their peak levels in the 1970s. Congress is considering further tightening of acid rainrelated regulations. But threats remain to fish and tree populations in areas affected by acid rain, according to the report. Original research prepared for the study suggests that acid rain may weaken plant life in a way that provides the knockout punch for species like red spruce and sugar maple trees. Acid rain has long history Vegetation already under stress from a variety of other pressures -- insect infestation, drought, climate change, and more -- may suffer cumulative damage from exposure to acidified soils. Of particular interest in the study area are the sugar maples. A backbone of commerce in northern New Hampshire and Vermont, the trees that produce maple syrup are already predicted to be endangered by a warming climate. Acid rain, first identified as an environmental risk in 1872, was not recognized as a major environmental problem until more than a century later. Reports of sterile lakes and dying forests in eastern North America, Scandinavia, Germany, Poland and Russia were linked to high acidity levels in waterways and soils. Those acid levels were in turn traced to airborne, highly acidic chemicals like sulfur dioxide, emitted from smokestacks through the burning of fossil fuels. Coal with high sulfur content, used to fuel factories and electric-generating stations, was identified by researchers as the leading contributor. Ironically, local pollution concerns near factories and power plants helped spread the acid rain problem. Political pressure forced many coal-burning facilities to build extremely high smokestacks -- reducing serious pollution problems near the plants, but enabling the acid rain chemicals to be transported hundreds, or even thousands, of miles away from the source. Coal-burning power plants in the Ohio River Valley, for example, are cited as a major source of the acid rain problems in New England and eastern Canada

Acid rain destroys trees and foliage EPA`7 6/07 http://www.epa.gov/acidrain/effects/forests.html Acid rain does not usually kill trees directly. Instead, it is more likely to weaken trees by damaging their leaves, limiting the nutrients available to them, or exposing them to toxic substances slowly released from the soil. Quite often, injury or death of trees is a result of these effects of acid rain in combination with one or more additional threats. Scientists know that acidic water dissolves the nutrients and helpful minerals in the soil and then washes them away before trees and other plants can use them to grow. At the same time, acid rain causes the release of substances that are toxic to trees and plants, such as aluminum, into the soil. Scientists believe that this combination of loss of soil nutrients and increase of toxic aluminum may be one way that acid rain harms trees. Such substances also wash away in the runoff and are carried into streams, rivers, and lakes. More of these substances are released from the soil when the rainfall is more acidic. However, trees can be damaged by acid rain even if the soil is well buffered. Forests in high mountain regions often are exposed to greater amounts of acid than other forests because they tend to be surrounded by acidic clouds and fog that are more acidic than rainfall. Scientists believe that when leaves are frequently bathed in this acid fog, essential nutrients in their leaves and needles are stripped away. This loss of nutrients in their foliage makes trees more susceptible to damage by other environmental factors, particularly cold winter weather. Top of Page How Acid Rain Affects Other Plants Acid rain can harm other plants in the same way it harms trees. Although damaged by other air pollutants such as ground level ozone, food crops are not usually seriously affected because farmers

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frequently add fertilizers to the soil to replace nutrients that have washed away. They may also add crushed limestone to the soil. Limestone is an alkaline material and increases the ability of the soil to act as a buffer against acidity.

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Dimming Bad-Dimming=Famine Dimming has already killed millions by famine, continuation sends it to the billions Shah`5(Anup, Global Dimming, GlobalIssues.org, January 15, 2005http://www.globalissues.org/EnvIssues/GlobalWarming/globaldimming.asp#Burningoffossilfuelsiscreatingtwoeffects)

Global warming results from the greenhouse effect caused by, amongst other things, excessive amounts of greenhouse gases in the earth’s atmosphere from fossil fuel burning. It would seem then, that the other byproducts which cause global dimming may be an ironic savior. A deeper look at this, however, shows that unfortunately this is not the case. Health and environmental effects. The pollutants that lead to global dimming also lead to various human and environmental problems, such as smog, respiratory problems, and acid rain. The impacts of global dimming itself, however, can be devastating. Millions from Famines in the Sahel in the 70s and 80s The death toll that global dimming may have already caused is thought to be massive. Climatologists studying this phenomenon believe that the reflection of heat have made waters in the northern hemisphere cooler. As a result, less rain has formed in key areas and crucial rainfall has failed to arrive over the Sahel in Northern Africa. In the 1970s and 1980s, massive famines were caused by failed rains which climatologists had never quite understood why they had failed. The answers that global dimming models seemed to provide, the documentary noted, has led to a chilling conclusion: “what came out of our exhaust pipes and power stations [from Europe and North America] contributed to the deaths of a million people in Africa, and afflicted 50 million more” with hunger and starvation. Billions are likely to be affected in Asia from similar effects Scientists said that the impact of global dimming might not be in the millions, but billions. The Asian monsoons bring rainfall to half the world’s population. If this air pollution and global dimming has a detrimental impact on the Asian monsoons some 3 billion people could be affected

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Aerosols = Famine Sulfate aerosol cooling leads to African famine and potential Asian monsoon failure, causing massive death through famine Eyles 2004 (John, director of the Institute of Environment and Health at McMaster University in Ontario, “What's at risk? Environmental influences on human health”, Environment, October 1, 2004, Pg. 24) As examples of the human health risks posed by contaminated water, air, and food suggest, it is not just the complex interactions among environmental factors that are responsible for a particular pattern of death and disease. Economic, political, and cultural systems play a large role as well. Another recent case--of the relationship between pollution, famine, malnutrition, and ill health in parts of the tropical world--is illustrative. Large areas of industrial haze have been found over the northern Indian Ocean and western Africa. In the former case, air quality degradation covers, during the winter monsoon, an area in excess of 10 million km, largely produced by biofuel use and agricultural burning. (63) This problem is likely to worsen as more fossil fuels are used, leading to photochemical reactions. The impacts of this global plume await study, but some clues can be taken from the African experience. According to Australian researchers, air pollution is likely to have contributed to the catastrophic Sahel drought as sulfate aerosol makes cloud droplets smaller. (64) Smaller droplets in turn make the clouds bigger and longer lasting, reflecting more sunlight into space, cooling the surface below. As a result, the tropical rain belt is weakened in the Northern Hemisphere. Since the 1960s, the Sahel has experienced devastating drought, leading to widespread famine and death. (65) Such complex natural reactions to human activity lead to a double jeopardy for citizens of the developing world: Activities to assist economic development lead to problems, compounding those from the routine hazards of living in such places.

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Aerosols = Famine, Drought Sulfate aerosol cooling deprives Africa of rainfall, causing massive droughts and famines and killing millions, air pollution reductions are necessary to prevent future droughts and famines Nowak 2002 (Rachel, “How the rich stole the rain; Pollution from the West may have plunged Africa into drought”, New Scientist, June 15, 2002, ln) EMISSIONS spewed out by power stations and factories in North America and Europe may have sparked the severe droughts that have afflicted the Sahel region of Africa. The droughts have been among the worst the world has ever seen, and led to the infamous famines that crippled countries such as Ethiopia in the 1980s. Climate experts have long worried that greenhouse gases are altering the climate on a global scale. But this is the first time they have suggested that industry and power-generation in the north may have disrupted regional weather in poor nations in tropical Africa, affecting a swath of countries from Ethiopia to Senegal. The cause appears to be the clouds of sulphur belched out alongside the soot, organic carbon, ammonium and nitrate produced when fossil fuels are burnt, according to researchers in Australia and Canada. As these compounds move through the atmosphere, they create aerosols that affect cloud formation, altering the temperature of the Earth's surface and leading to dramatic shifts in regional weather patterns. In the past thirty to forty years, the Sahel--a loosely defined band across Africa, just south of the Sahara and including parts of Ethiopia in the east and Guinea in the west--has suffered the most sustained drought seen in any part of the world since records began, with precipitation falling by between 20 and 50 per cent. Although the droughts have had climate experts scratching their heads, the impacts have been obvious. During the worst years, between 1972 and 1975, and 1984 and 1985, up to a million people starved to death. Now Leon Rotstayn of the CSIRO, Australia's national research agency, thinks he knows what caused them. Rotstayn and his colleague Ulrike Lohmann of Dalhousie University in Halifax, Nova Scotia, ran a simulation of global climate that included interactions between sulphur dioxide emissions and cloud formation. Sulphur dioxide creates sulphate aerosols that provide condensation nuclei for clouds. With more nuclei, clouds form from smaller droplets than usual, and are more efficient at reflecting solar radiation, cooling the Earth below. When the researchers included the huge sulphur emissions from the northern hemisphere during the 1980s in their model, the Earth's surface in the north cooled relative to the south, driving the tropical rain belt south and causing droughts in the Sahel. Their results will be reported soon in the Journal of Climate. "It's still speculative, and the model isn't very refined, but it's very interesting. It's the first time we've seen a connection between pollution in the mid-latitudes and climate in the tropics," says Johann Feichter of the Max Planck Institute for Meteorology in Hamburg. Feichter, who has run similar simulations but cannot talk about the results because the research is being peer-reviewed for a major journal, says the sulphur emissions probably worsen the natural cycle of droughts that would have happened anyway. During the past few years, the droughts have become less severe, a change that Rotstayn puts down to the "clean air" laws in North America and Europe that reduced sulphur dioxide emissions in response to another environmental crisis, acid rain. "Sulphur emissions increased rapidly until 1975 due to post-war industrialisation, and then started to decline when emission controls were brought in. Maybe that indirectly helped the people in Africa as well," he says.

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Aerosols Bad - SLR, Drought, Famine Reliance on aerosols to offset warming will not prevent sea level rise, drought, and famine due to a lack of aerosol protection for the Southern Hemisphere Berreby 1993 (David, Staff Writer, “The parasol effect - sulfate aerosols block sun's rays and may cause cooling”, Science, http://www.findarticles.com/p/articles/mi_m1511/is_n7_v14/ai_13923194/print) But opposite in effect. Is the aerosol umbrella, then, a mandate to do nothing about global warming? Or to do nothing about reducing sulfur emissions? In a word, Charlson says, no. To him, the notion that humanity could fine-tune a system as big and complex as the climate is laughable. "There's always this temptation to tell ourselves we can handle it, that we're bigger than it is," he says. "Personally, I find that attitude very arrogant. It assumes that we understand climate well enough to engineer it, and we don't." Some of Charlson's findings about the parasol effect suggest that it won't help at all with some serious aspects of the global warming problem, such as rising sea levels. Sulfate aerosols may even make some warming effects worse, Charlson says. The reasons lie in the fundamental difference between greenhouse gases--which rise to the stratosphere and cover the globe--and sulfates, which travel only a few hundred miles. Because sulfates have such a limited range, almost all man-made aerosols are floating above the Northern Hemisphere, where 90 percent of industrial activity is still concentrated. By contrast, the Southern Hemisphere gets almost no such "protection" from man-made sulfates. Even in the relatively clean air of Seattle, Charlson says, "the amount of light scattered by haze is probably 10 to 100 times higher than it is in the Southern Hemisphere." With one hemisphere bearing the full brunt of global warming while the other is protected by an umbrella of pollution, he says, seas would still rise uniformly all over the globe, as the warmer southern waters expand. In other words, sulfates can't save the Maldives, the low-lying island nation in the Indian Ocean. But a rise in sea levels, Charlson says, might not be the biggest effect to worry about. Much more important, he points out, could be the increased difference in temperature between the two hemispheres. That's likely to affect the large-scale weather systems on which people depend. "More frequent occurrence of drought is a possibility," Charlson says. "Or of violent storms. Or the opposite--less frequent storms. I'd give either chance equal billing. The thing people need to understand is that a slight regional shift in any direction is a big concern. Last year in the mountains around Seattle we had more precipitation as rain and less as snow than normal. And the snowpack is our reserve of water that fills the reservoirs in late spring. So just because the balance of snow to rain changed, we had a drought here."

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Dimming=Drought [1/2] Dimming causes drought-Less moisture Akina`7(Jennifer, Drought: Effect of Global Dimming, Mar 23, 2007, http://www.associatedcontent.com/article/24881/drought_effect_of_global_dimming.html)

Air pollutants such as soot, ash and sulfur dioxide are created from the use of fossil fuels which contribute to what scientists call global dimming. In short, global dimming occurs when clouds reflect more of the sun's rays back into space than they normally would, thus, allowing less heat and energy to reach the earth's surface. Recent research has shown that global dimming is likely to be the main cause behind the devastating droughts that have killed millions of people in so little as the past three decades. To better explain the process of global dimming, normal clouds are created when water droplets combine with natural air-borne particles like pollen. But, when these air-borne particles become polluted by soot and ash, clouds are formed with a much larger number of water droplets making the clouds "thicker" and more reflective of sun's rays. Sun rays which play a crucial role in making the earth a living, working ecosystem. Although global dimming may sound like a perfect counter measure to global warming, it is in fact the cause behind such global catastrophe's as the Ethiopian droughts in the 1970s and 1980s, killing millions of helpless villagers, along with the more recent European heat wave in 2003 left thousands dead. Scientists who have been studying this meteorological phenomenon believe that the reflection of the sun's heat has caused the oceans in the northern hemisphere to become cooler. As a result, less rain has formed across the planet because of less evaporation leading to clouds and rain. Crucial moisture once keeping areas livable, like that of Africa and other countries, is no longer filling lakes and rivers.

Droughts kill food security IRIN`8 (IRIN, Hummanitarian news and technology, NEPAL: Drought compounds food insecurity in western regions KATHMANDU, 24 June 2008, http://www.irinnews.org/Report.aspx?ReportId=78909)

More than 300,000 people in nine hill districts of far western and mid-western Nepal face a precarious food situation after the crops failed this year due to drought, the UN's World Food Programme (WFP) has warned. Although the Himalayan nation is largely dependent on food imported from neighbouring India, the local grain output provides vital reserves in many food-deficit districts. However, the crop yield this year has been so poor it has left many without coping mechanisms, according to the UN food agency. "The food security situation for many communities living in these regions is very worrying," WFP's country director Richard Ragan told IRIN in the capital Kathmandu. Nepal is divided into five development regions - east, west, central, mid-west and far west. Of these, the latter two are considered the least developed due to their difficult terrain and remoteness. These food-deficit districts include Accham and Bajura in the far west and Kalikot, Mugu, Dolpa, Humla, Jajarkot, Dailekh and Rukum in the mid-west. Most lack navigable roads and are 500-700km north of the capital. The districts also have the country's highest rates of child malnutrition, according to government health statistics. Food shortage risks "[The] food crisis could get worse this year because of the combined factors of drought-led crop failures and high food prices," said Rajendra Khadga Chettri, director of Support Activities for Poor Producers of Nepal (SAPPROS), a local NGO involved in agricultural technology and irrigation projects, which helps foodinsecure communities. "Hunger and starvation are increasing among villagers. In addition, more villagers are at risk of food shortage as their food stocks will not even last for two months," said Chettri. WFP field monitors reported that nearly 50,000 people in three districts of Bajura, Dailekh and Jajarkot were experiencing an acute food security situation. Since the beginning of June, an estimated 252,000 people in Kalikot, Dolpa, Bajura, Accham, Dailekh, Rukum and Jajarkot are facing food insecurity with little chance of recovery.

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Dimming Bad-SO2 Kills thousands Air Pollution in China has a 10,000 person death toll and costs billions of dollars China Daily`8HK Edition June 12, 2008 http://www.china.org.cn/environment/news/200806/12/content_15764178.htm

Poor air quality in the Pearl River Delta Region (PRD), Hong Kong and Macao cost 10,000 lives in 2006 and results in heavy productivity loss and medical expenses every year, according to a study released yesterday. The study, which was commissioned by public policy think tank Civic Exchange and conducted by academics from local universities, said air pollution was responsible for 440,000 annual hospital-bed days and 11 million outpatient visits throughout the region. The relative loss of productivity and medical expenses incurred amounted to 1.8 billion yuan in the PRD, HK$1.1 billion in Hong Kong and HK$18 million in Macao. In the opinion of Civic Exchange chief executive officer Christine Loh, improvement of regional air quality requires concerted efforts of all concerned parties. In this connection, Hong Kong and Guangdong should cooperate more closely before the East Asian Games is held in Hong Kong next year and the 2010 Asian Games in Guangzhou. They should take advantage of Beijing's experience in improving air quality for the Olympic Games, Loh said. Presenting the findings of the study, professor Alexis Lau from the Hong Kong University of Science and Technology's Institute of Environment said the number of clear days in a year decreased from 1997 to 2006 owing to heavy presence of respirable suspended particulates (RSP). The researchers based their study on 2006 data collected from Hong Kong and Guangdong environment authorities. The 2007 situation was worse than 2006, Lau added. As pointed out by professor Anthony Hedley of the School of Public Health of the University of Hong Kong, the SAR government is currently adopting air quality objectives formulated in 1987 which are not as demanding as those set by the World Health Organization (WHO) in 2005. The WHO objectives focus on four major air pollutants namely: RSP, nitrogen dioxide, sulphur dioxide and ozone. To improve air quality and protect public health, Lau suggested the government adopt the more stringent WHO air quality objectives.

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AT: Dimming Solves Plankton Increased ocean acidity from leads to a decrease in plankton STPNS`7

(George Zamora, March 08, 2007 SCIENCE Researchers Study Ocean Acidity Effects On Climate, http://www.stpns.net/view_article.html?articleId=32146512128703628)

In the article titled “Unexpected consequences of increasing CO2 and ocean acidity on marine production of DMS and CH2CH: Potential climate impacts,” Wingenter and his research colleagues have determined that by increasing atmospheric mixing ratios of carbon dioxide, the scientists were then able to make ocean surface waters three times more acidic than normal. Wingenter’s co-authors include then New Mexico Tech undergraduates Karl Haase and Max Ziegler, as well as research colleagues from the University of Bergen, the University of New Hampshire, the University of Kiel in Germany, and the University of California at Irvine. Ziegler is now a graduate student at the University of Washington. Karl is a graduate student at the University of New Hampshire. Other recent studies have shown that ocean acidity is rising at a rate of about 100 times faster than at any known time, Wingenter said, but this newly published study links the effect of increasing ocean acidity to changes in phytoplankton ecosystems that consume and produce carbon dioxide and other organic “greenhouse gases.” “Pronounced physiological changes in some phytoplankton have been observed during previous CO2 perturbation experiments,” Wingenter said. “Although the changes in ocean acidity can be predicted, the consequences for marine organisms, their ecosystems, and climate-relevant organic gas emissions are largely unknown.” In their month-long field experiment, conducted in late spring of 2005 at the Large-Scale Marine Facilities of the University of Bergen, Norway, Wingenter and his research team used three sets of three large plastic bags — two meters in diameter, and filled to a depth of 10 meters with seawater — to simulate present-day carbon dioxide concentrations and ocean acidity, as well as CO2 levels that are expected to be found at the end of this

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century and the middle of the next one. During the study, concentrations of dimethyl sulfide (DMS) and chloroiodomethane, which are produced by phytoplankton in the ocean water, were analyzed, measured and recorded. “Marine microorganisms produce DMS, which is a radiatively important gas,” Wingenter said. “In the atmosphere, DMS is rapidly oxidized to sulfur dioxide, which can form sulfate aerosols. “As a result, emissions of DMS are a major source of cloud condensation nuclei in the clean marine atmosphere,” he added. “In addition, chloroiod-omethane and other iodocarbons produced by phytoplankton quickly react with sunlight in the atmosphere and end up releasing iodine that can destroy ozone and lead to aerosol nucleation,” Wingenter said. The marked increases in the climate-relevant gases and ocean acidity observed in the study may be directly attributable to changes the phytoplankton’s environment brought on by adding more carbon dioxide, the researchers said in their paper. “Enhanced future production of these gases may contribute to planetary cooling and may eventually slow down global warming,” Wingenter said. “This experimental study points to the need for similar work to determine the changes in other phytoplankton communities in response to future CO2 concentrations and any resultant changes in organic gas production,” said Wingenter. “Combining future experimental and modeling efforts will lead to a better understanding of the feedback systems between the atmosphere and ocean in the future,” he said

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AT: Dimming solves marine ecosystems Acid rain wreaks havoc on marine ecosystems EPA`7 (Enviromental Protection Agency, Effects of Acid Rain - Surface Waters and Aquatic Animals, June 8th, 2007, http://www.epa.gov/acidrain/effects/surface_water.html#a2)

Acid rain causes a cascade of effects that harm or kill individual fish, reduce fish population numbers, completely eliminate fish species from a waterbody, and decrease biodiversity. As acid rain flows through soils in a watershed, aluminum is released from soils into the lakes and streams located in that watershed. So, as pH in a lake or stream decreases, aluminum levels increase. Both low pH and increased aluminum levels are directly toxic to fish. In addition, low pH and increased aluminum levels cause chronic stress that may not kill individual fish, but leads to lower body weight and smaller size and makes fish less able to compete for food and habitat. Some types of plants and animals are able to tolerate acidic waters. Others, however, are acidsensitive and will be lost as the pH declines. Generally, the young of most species are more sensitive to environmental conditions than adults. At pH 5, most fish eggs cannot hatch. At lower pH levels, some adult fish die. Some acid lakes have no fish. The chart below shows that not all fish, shellfish, or the insects that they eat can tolerate the same amount of acid; for example, frogs can tolerate water that is more acidic (i.e., has a lower pH) than trout.

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AT: Dimming Solves Disease Acid Rain=Acidification

Science Master`99 (Science Master.com, with information from the EPA, JumpStart - Earth Science Environmental Effects of Acid Rain* April 1999, http://www.sciencemaster.com/jump/earth/acid_rain.php) Scientists have discovered that air pollution from the burning of fossil fuels is the major cause of acid rain. Acidic deposition, or acid rain as it is commonly known, occurs when emissions of sulfur dioxide (SO2) and oxides of nitrogen (NOx) react in the atmosphere with water, oxygen, and oxidants to form various acidic compounds. This mixture forms a mild solution of sulfuric acid and nitric acid. Sunlight increases the rate of most of these reactions. These compounds then fall to the earth in either wet form (such as rain, snow, and fog or dry form (such as gas and particles). About half of the acidity in the atmosphere falls back to earth through dry deposition as gases and dry particles. The wind blows these acidic particles and gases onto buildings, cars, homes, and trees. In some instances, these gases and particles can eat away the things on which they settle. Dry deposited gases and particles are sometimes washed from trees and other surfaces by rainstorms. When that happens, the runoff water adds those acids to the acid rain, making the combination more acidic than the falling rain alone. The combination of acid rain plus dry deposited acid is called acid deposition. Prevailing winds transport the compounds, sometimes hundreds of miles, across state and national borders. Electric utility plants account or about 70 percent of annual SO2 emissions and 30 percent of NOx emissions in the United States. Mobile sources (tranportation) also contribute significantly to NOx emissions. Overall, over 20 million tons of SO2 and NOx are emitted into the atmosphere each year. Acid rain causes acidification of lakes and streams and contributes to damage of trees at high elevations (for example, red spruce trees above 2,000 feet in elevation). In addition, acid rain accelerates the decay of building materials and paints, including irreplaceable buildings, statues,and sculptures that are part of our nation's cultural heritage. Prior to falling to the earth, SO2 and NOx gases and their particulate matter derivatives, sulfates and nitrates, contribute to visibility degradation and impact public health.

B) Newly emerging diseases need acidification to spread from mosquitoes-VEEV Colpitts et al. 2007 (Colpitts TM, Moore AC, Kolokoltsov AA, Davey RA. Department of Microbiology and Immunology, Center for Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, USA, Venezuelan equine encephalitis virus infection of mosquito cells requires acidification as well as mosquito homologs of the endocytic proteins Rab5 and Rab7., Pub Med, December 2007, http://www.ncbi.nlm.nih.gov/pubmed/17707875)

Venezuelan equine encephalitis virus (VEEV) is a New World alphavirus that can cause fatal encephalitis in humans. It remains a naturally emerging disease as well as a highly developed biological weapon. VEEV is transmitted to humans in nature by mosquito vectors. Little is known about VEEV entry, especially in mosquito cells. Here, a novel luciferase-based virus entry assay is used to show that the entry of VEEV into mosquito cells requires acidification. Furthermore, mosquito homologs of key human proteins (Rab5 and Rab7) involved in endocytosis were isolated and characterized. Rab5 is found on early endosomes and Rab7 on late endosomes and both are important for VEEV entry in mammalian cells. Each was shown to have analogous function in mosquito cells to that seen in mammalian cells. The wild-type, dominant negative and constitutively active mutants were then used to demonstrate that VEEV requires passage through early and late endosomes before infection can take place. This work indicates that the infection mechanism in mosquitoes and mammals is through a common and ancient evolutionarily conserved pathway.

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AT: Dimming solves drought Aerosols exacerbate warming, flood, and drought Page`7 (Jeremy, The London Times, August 3, 2007, Friday

Giant toxic cloud may bring flood and droughts to two billion

people, Lexis)

They call it the Asian Brown Cloud. Anyone who has flown over South Asia has seen it -a vast blanket of smog that covers much of the region. It is also what colours those sunsets at the Taj Mahal. Now a group of scientists has carried out the first detailed study of the phenomenon and arrived at a troubling conclusion. They say that it is causing Himalayan glaciers to melt, with potentially devastating consequences for more than two billion people in India, China, Bangladesh and other downstream countries. In a study published yesterday by Nature, the British journal, they say that black soot particles in the cloud are absorbing the Sun's heat and pushing up temperatures at the same altitude as most Himalayan glaciers. Scientists have already observed that two thirds of the 46,000 glaciers in the Himalayas are shrinking, leading to increasingly severe floods downstream and, eventually, to widespread drought. Greenhouse gases were previously thought to be the main cause of the problem, which threatens the sources of Asia's nine main rivers -including the Indus, the Ganges and the Yangtze. But the research team from the Scripps Institution of Oceanography in California says that the Asian Brown Cloud -made up of gases and suspended particles known as aerosols -is just as much to blame. "My one hope is that this finding will intensify the focus of Asian scientists and policy makers on the glacier issue," Veerabhadran Ramanathan, who led the research, told The Times. "These glaciers are the source for major river systems, so at least two billion people are directly involved in this." The cloud is an enormous plume of smoke from factories, power plants and wood or dung fires that stretches across the Indian subcontinent, into SouthEast Asia. Professor Ramanathan's team examined it using three unmanned aircraft similar to those used by the US military, but fitted with fifteen instruments to measure temperature, humidity and aerosol levels. The drones were launched from the Maldives island of Hanimadhoo and carried out 18 missions over the Indian Ocean in March 2006, flying simultaneously through the cloud at different altitudes. They found that the cloud amplified the effects of solar heating on the surrounding air by 50 per cent.

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AT: Dimming-Not a developing problem Dimming isn’t a problem for developing Asian countries Page`7 (Jeremy, The London Times, August 3, 2007, Friday

Giant toxic cloud may bring flood and droughts to two billion

people, Lexis)

The professor said that some aerosols in the cloud reflected sunlight, cooling the earth beneath in a process known as "global dimming" that is also worrying climate change experts. Others absorbed heat radiation from the Sun because of their dark colour. When he put his data into a computer model for climate change, it estimated that Himalayan temperatures had risen 0.25C (0.45F) a decade since 1950 -twice the average rate of global warming. "If we continue to use outdated technology to achieve industrialisation, this is only going to get worse," said Professor Rama- nathan. "But there is some good news." Unlike greenhouse gases, which can stay in the atmosphere for 200 years, aerosols drop to the ground after two to three weeks. Asian countries can therefore tackle the problem relatively quickly if they find alternatives to fuels such as coal, diesel, wood and dung, which account for the majority of aerosols in the air.

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AT: Dimming-Not conclusive Global dimming decreasing now, plus there’s not enough research to be certain without it earth will warm Cox`5 (Brian, Popular Science, The Sun is Dying and Global Dimming, http://www.popularscience.co.uk/features/feat28.htm, 2005)

It is now suspected that pollution in the Earth's atmosphere, caused by industrialization and natural phenomena such as volcanic eruptions, may have significantly reduced that amount of sunlight reaching the Earth's surface. It is estimated that this could have led to a cooling effect of over 1 degree overt he last 40 years, which would go some way to offsetting the effect of global warming. Global warming is caused primarily by increasing carbon dioxide levels in the atmosphere that prevent heat being radiated back out into space from the Earth's surface. The phenomenon of global dimming may therefore have saved us, so far, from the worst affects of climate change, although it has been noticed that as pollution levels have been reduced, particularly in Western Europe, the affects of global dimming seem to be reducing, leading to an accelerating temperature rise once again. We may therefore be in the paradoxical situation that reducing pollution might INCREASE the effects of global warming, leading us ever more quickly towards catastrophe. This discovery isn't all bad, however, because it may suggest a short term solution to climate change. Why not intentionally put pollutants, which may be designed to be benign in other respects, into the atmosphere to accelerate global dimming, and therefore slow the climate change caused by carbon dioxide emissions. Several suggestions along these lines have been made, including adding small particles to airplane fuel, and therefore using one of the main contributors to climate change, aircraft, to slow its effects. It's an intriguing possibility, and one that is the focus of significant research, although it should be said that we cannot at present predict the effects of such fine-tuning of the climate, so global dimming shouldn't be seen as a means to allow us to continue to increase carbon dioxide emissions.

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AT: Dimming-Aerosols=More warming-Black Carbon The black carbon that is apart of the aerosol mix results in a net increase in temperature Randerson`8(James, Science Correspondent for the Guardian-London News service, Scientists warn of soot effect on climate: Coal and wood 'more damaging than thought': Black carbon harms environment and health, March 24, 2008 Monday, Lexis.)

Soot produced by burning coal, diesel, wood and dung causes significantly more damage to the environment than previously thought, according to research published today. So-called "black carbon" could cause up to 60% of the current warming effect of carbon dioxide, according to the US researchers, making it an important target for efforts to slow global warming. Around 400,000 people are estimated to die each year due to inhaling soot particles, particularly because of indoor cooking on wood and dung stoves in developing countries. These deaths are mainly among women and children. Professor Greg Carmichael, of the University of Iowa, one of the authors of the study, published in Nature Geoscience, said: "Trying to develop strategies that really go after black carbon is really a very good short-term strategy and a win-win strategy for both climate and air pollution perspectives." Carmichael and Professor V Ramanathan, at Scripps Institution of Oceanography in San Diego, put together data from satellites, aircraft and surface instruments on the warming effect from black carbon. They conclude that its effect in the atmosphere is around 0.9 watts per square metre, considerably higher than the estimate of between 0.2 and 0.4 watts in last year's report from the Intergovernmental Panel on Climate Change. Most particulates in the atmosphere reduce the warming effect from greenhouse gases by bouncing radiation back into space - so-called global dimming. But black carbon has the opposite effect and Ramanathan and Carmichael argue that its contribution to global warming has been underestimated. "The aerosols in aggregate are either acting to, you could say, cool the atmosphere or mask the effect of CO2," said Carmichael, "(Black carbon) is the only component of this aerosol mix that in and of itself is a heating element." Previous estimates had not taken into account the fact that it has a larger impact at high altitude in the atmosphere and that it interacts with other particulates in the atmosphere. Scientists do not fully understand these interactions, but observations suggest that they result in more warming. The researchers said that programmes to replace wood-burning stoves with clean technology such as solar energy in developing countries such as India should be pursued to reduce the number of deaths caused by inhaling the smoke. The authors stressed that these measures were not a magic bullet. "It is important to emphasise that black carbon reduction can only help delay and not prevent unprecedented climate changes due to CO2 emissions," they wrote.

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AT: Dimming-Aerosols 90% natural 90% of all aerosols occur naturally-Plan doesn’t change those NASA` No date (National Aeronautics and Space Administration, What Are Aerosols? http://terra.nasa.gov/FactSheets/Aerosols/)

Aerosols are tiny particles suspended in the air. Some occur naturally, originating from volcanoes, dust storms, forest and grassland fires, living vegetation, and sea spray. Human activities, such as the burning of fossil fuels and the alteration of natural surface cover, also generate aerosols. Averaged over the globe, aerosols made by human activities currently account for about 10 percent of the total amount of aerosols in our atmosphere. Most of that 10 percent is concentrated in the Northern Hemisphere, especially downwind of industrial sites, slash-and-burn agricultural regions, and overgrazed grasslands. Scientists have much to learn about the way aerosols affect regional and global climate. We have yet to accurately quantify the relative impacts on climate of natural aerosols and those of human origin. Moreover, we do not know in what regions of the planet the amount of atmospheric aerosol is increasing, is diminishing, and is remaining roughly constant. Overall, we do not even know whether aerosols are warming or cooling our planet.

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AT: Dimming-Asia SO2 solves [1/2] No impact-SO2 Will still come from Asia Notholt`5J., et al., 2005. Influence of tropospheric SO2 emissions on particle formation and the stratospheric humidity. Geophysical Research Letters, 4/5/05 http://www.worldclimatereport.com/index.php/2005/04/22/change-of-direction-do-so2emissions-lead-to-warming/

Many scientists believe that sulfur dioxide emissions, either from un-scrubbed power plants or from largescale agricultural burning, serve to cool the planet’s surface temperature. The cooling mechanism is fairly straightforward. Sulfur dioxide is transformed in the atmosphere into sulfate aerosol, a fine particle that reflects away the sun’s radiation. The particles also serve as the condensation nuclei for cloud droplets which also reflect away the sun’s energy. On the other hand, no one really knows the magnitude of these cooling effects (if any). So we have argued that sulfate cooling is simply a fudge factor put into climate models in order to chill the overly-hot projections they make if left to their own devices. Now comes evidence that sulfur dioxide actually can enhance global warming. While this doesn’t mean that sulfates aren’t also cooling things by reflecting away radiation, the parent, sulfur dioxide, can do some other things that make the surface warmer. According to research just published in Geophysical Research Letters by J. Notholt and his co-authors, sulfur dioxide is converted to sulfuric acid (remember “acid rain”?), which leads to more ice crystals in the upper atmosphere. Some of these are eventually lifted upwards into the stable stratosphere where they increase the amount of water vapor found there. Water vapor in the stratosphere serves as a greenhouse gas and is involved in the destruction of ozone, resulting in a stratospheric cooling and a warming of the lower atmosphere and surface. And, for once, it’s not from the USA. We’re usually blamed for the lion’s share of warming as a result of our carbon dioxide emissions. But the sulfur dioxide is largely from elsewhere. The authors write: While anthropogenic SO2 emissions in Europe and North America have been decreasing since around 1980, the anthropogenic SO2 emissions from China, Asia and the tropics have been increasing…For example, van Aardenne et al (2001) report a factor of 12 increase for China and 8 for East Asia, respectively between 1950 and 1990. The authors propose that their mechanism has been responsible for about one-quarter of the increases in stratospheric water vapor during the period 1950 to 2000. According to a NASA model published by Drew Shindell in 2001, this would account for about 5% of the observed warming. While that seems small, it is a sign about how little we really know (or have known) about the climatic disposition of sulfur dioxide. Every increment of warming that it causes takes away from its putative cooling. Which means, ironically, that it can serve less and less as an explanation as to why we have only witnessed a very modest

China emits tons of SO2 Asia news`6 http://www.asianews.it/index.php?art=6906&l=en 08/06 Sulphur dioxide, acid rain: pollution on the rise in Chinese cities High coal consumption is the major culprit of pollution that also affects other countries. Annual losses of more than 510 billion yuan and serious respiratory illnesses are two of the consequences. Local authorities resist implementing measures to monitor the environment. Beijing (AsiaNews/SCMP) – China last week admitted to being the world's largest sulphur dioxide polluter, emitting nearly 26 million tons of the gas in 2005. This means a 27% increase since 2000 and according to Li Xinmin, an official of the State Environmental Protection Administration (SEPA), it coincided with a rise in coal consumption, which accounts for 70% of energy produced. Li said it "was difficult to change the situation in the short term" and the government was planning a 10% reduction in emissions from industrial plants by not earlier than 2010. An increase in the use of cars has also led to increased gas emissions. The gas contributes to acid rain that also affects neighbouring countries like Hong Kong and Japan, and it could cause severe respiratory illnesses. Official sources said this pollution leads to "economic losses" amounting to around 510 billion yuan per year. Added to this are costs in terms of health: a study by the School of Public Health of the University of Fudan estimated that air pollution costs Shanghai alone more than eight billion yuan per year for medical expenses. Xu Kezhu, professor of Environmental Law of China University for law and political sciences, said China's laws stipulated that polluting plants should install devices to cut back on emissions but this regulation was poorly applied because of protectionism from the local authorities and the large number of existing plants. Xu said: "The [continues on next page, no text removed]

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AT: Dimming-Asia SO2 Solves [2/2] problem is that the limits are not clearly laid down and there is no precise application of laws when pollution is caused." He continued: "Many factories still do not use anti-polluting devices or else they issue gas at night... Local governments do not monitor the situation carefully to identify and sanction polluters." Chen Dongmei, director of the Climate Change and Energy programme of the World Wildlife Fund in China agreed that although the central government may want to rein in pollution, this "is sometimes not understood by the local authorities". Beijing, meanwhile, denies pollution could affect other nations, especially the United States. Recently, some scholars accused China of causing 25% of the air pollution in cities like Los Angeles. Li said: "Those reports saying 25% of pollution in Los Angles comes from China are not objective and are irresponsible and the conclusion is also doubtful." Li said further, better studies were needed to assess both the polluting effect caused to other nations as well as the exact influence of meteorological phenomena. Meanwhile, on 2 August, the Xinao Group, the Chinese leading gas distributor, obtained significant funding from the International Finance Corp, a private operator of the World Bank, to convert coal into dimethyl ether, a gas used for heating and cooking and thought to be nonpolluting.

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AT: “Cool waters mean we solve sea level” Cooling doesn’t reduce sea level Science Daily, No date (Science Daily.com, News From the Scientific community, Sea Level, http://www.sciencedaily.com/articles/s/sea_level.htm)

"This research suggests global warming isn't always steady, but happens with occasional 'speed bumps'," said Josh Willis, a co-author of the study at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "This cooling is probably natural climate variability. The oceans today are still warmer than they were during the 1980s, and most scientists expect the oceans will eventually continue to warm in response to human-induced climate change." Willis said the findings have significant implications for global sea-level rise. "Average sea level goes up partly due to warming and thermal expansion of the oceans and partly due to runoff from melting glaciers and ice sheets," Willis said. "The recent cooling episode suggests sea level should have actually decreased in the past two years. Despite this, sea level has continued to rise. This may mean that sea level rise has recently shifted from being mostly caused by warming to being dominated by melting. This idea is consistent with recent estimates of icemass loss in Antarctica and accelerating ice-mass loss on Greenland," he said.

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Coal Aerosols Not Offset Warming Coal power plants are not an effective aerosol cooling mechanism because emissions remain in the lower atmosphere The Boston Herald 2006 (“Can pollution cure global warming?”, October 29, 2006, pg 18) According to an article in last week's issue of Science magazine by Thomas M.L. Wigley, the 1991 eruption of Mount Pinatubo in the Philippines cooled the atmosphere in the short term ``but did not seriously disrupt the climate system.'' The cooling, an average of 0.7 to 0.9 degree Fahrenheit, lasted two years. It was caused by sulfate aerosol particles around the globe formed from about 11 million tons of sulfur dioxide thrown into the atmosphere in the eruption of the 5,725-foot mountain. The sulfate particles increased the amount of the sun's radiation reflected back into space. Sulfur dioxide is a major pollutant of coal-burning power plants that do not clean up the stack gases. Power plants would not be a suitable mechanism for duplicating a volcano eruption because their emissions would not reach high enough.

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Aerosols = Disease Exposure to aerosols and particulates causes health problems and lowers disease resistance, increasing mortality Eyles 2004 (John, director of the Institute of Environment and Health at McMaster University in Ontario, “What's at risk? Environmental influences on human health”, Environment, October 1, 2004, Pg. 24) Because different pollutants have different health effects, what is measured and controlled is important. (35) In general, exposure to low levels of such pollutants as ozone, sulfur oxides, nitrogen oxides, and particulate matter can irritate the eyes and cause inflammation of the respiratory tract. Many air pollutants may also suppress the immune system, increasing susceptibility to infections. Following the nearly 2,500 deaths that occurred in London in December 1952, attention has been focused on particulate matter (PM). (36) In the last 30 years, consistent association has been found between PM and increases in mortality, hospital admissions, and morbidity. Most recently, in a study of 20 U.S. cities, increases in the relative rate of death from all causes and respiratory and cardiovascular causes were found with each increase in PM level. (37) A detailed study of Montreal found increases in daily mortality and most measures of particulate air pollution of the order of 1-2 percent. (38) While this seems small, it is a serious public health issue on a population level: For example, in cities of more than one million people, 1-2 percent equates to 10,000-20,000 people. Recent studies are revealing relationships between air quality and many adverse health outcomes, including asthma, lung cancer, cardiovascular disease, diabetes, stroke, and chronic obstructive pulmonary disease. (39) WHO officials stated in a 2000 Air Quality and Health meeting in Geneva that overall, air pollution from various sources contributes to 3 million deaths worldwide. (40) Because of the complexities of causation, this is merely an estimate; the actual death toll may be anywhere from 1.4 million to 6 million. Air pollution's influence on chronic morbidity is much more dramatic. One study concluded that there is an association between fine particulate matter, common in the air of most metropolitan areas, and increased risk of death due to lung cancer and cardiopulmonary disease. (41) A 2002 Dutch study found that people living near a main road were twice as likely to die of heart or lung disease more than those who did not. (42) Increases in and exposure to particulate air pollution have been shown to exacerbate asthma sufferers' symptoms, increasing rates of asthma attacks 3-5 days after coincident increased pollution levels. (43) Although most studies of the relationship between poor air quality and human health have been carried out in developed countries, it is a worldwide problem. For example, studies in Sao Paulo, Brazil, have shown that an increase of 75 micrograms per cubic meter in concentrations of nitrogen dioxide was related to a 30 percent increase in deaths from respiratory illness in children under 5 years of age. (44)

Gonzaga Debate Institute 2008 Scholars

104 Aerosols

Black Soot Counterbalancing Sulfate washout will create no warming, the soot emitted along with aerosols has a warming effect that counteracts aerosol cooling World Climate Report 2001 (“Smoking Out UN-Science”, World Climate Report, Feb 19, 2001, http://www.worldclimatereport.com/archive/previous_issues/vol6/v6n11/feature1.htm) In the article, Stanford engineer Mark Jacobson asserts that common black soot in the atmosphere—the stuff that goes up the smokestack along with other products of combustion, such as sulfate aerosols—exerts a whopping warming effect. The net direct warming that soot produces is greater than that from any other emission with the exception of carbon dioxide, Jacobson writes. That warming is almost exactly equal to the putative cooling directly caused by sulfate aerosol. If true, Jacobson's calculation has a number of neat effects. After all, sulfate aerosol and soot go hand in hand. Their combination is colloquially known as "smoke." Particles of both are about the same size. So any attempt to remove one (often done with electrostatic precipitators) will remove the other. If the size of the prevented warming then equals the size of the prevented cooling, the result is no net change in temperature as sulfates drop out. End of 11° story.

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