What Is Cyclone Sheet 1.docx

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WHAT IS CYCLONE? Cyclones are huge revolving storms caused by winds blowing around a central area of low atmospheric pressure. Wind blows anti-clockwise in the NH and clockwise in the SH

Typhoon- termed used when it formed in the Pacific ocean Hurricane- termed used when it formed in the Atlantic ocean Cyclone- termed used when it formed in the southern ocean and Indian ocean Willy-willy- termed used in Australia CYCLONE CAUSES conditions 1. Warm ocean waters at least (26.5°C) to provide the heat. 2. Availability of moisture. Moisture is necessary for providing latent heat of condensation. 3. Coriolis force to provide the rotation. (they do not form within 5o of the equator due to the negligible CF there). 4. A seedling or cyclonic weather disturbance with extra cloud cover. 5. Almost uniform large scale wind with little vertical shear to allow heat to accumulate (less than 10m/s). 6. An exhaust system consisting of a divergent upper level disturbance. CYCLONE INTENSIFICATION

Peak intensity of a typhoon is the maximum intensity the storm reaches during its entire lifetime. It results from an accumulation of intensification, which is equivalent to speed being an accumulation of acceleration. Cyclone can grow depends on two oceanic factors: pre-storm sea surface temperature difference in temperature between the surface and subsurface. A warmer sea surface generally provides more energy for storm development and thus favors higher intensification rates. EVAPORATION AND TEMPERATURE Evaporation increases rapidly as temperature increases.

Evaporation= energy in the form of latent heat that fuels the cyclone

EFFECTS OF DRY AIR AND DUST Dry air from Sahara can weaken storms Dust blocks the sun and cools the oceaN STAGES OF DEVELOPMENT

Tropical Disturbance: The birth of a hurricane, having only a slight circulation with no closed isobars around an area of low pressure. Tropical disturbances commonly exist in the tropical trade winds at any one time and are often accompanied by clouds and precipitation. Tropical Depression A tropical cyclone in which the maximum sustained wind speed less than 64 KPH. Depressions have a closed circulation Tropical Storm A tropical storm has a maximum sustained surface wind speed between 64 KPH and 117 KPH . The convection in tropical storms is usually more concentrated near the center with outer rainfall organizing into distinct bands. Typhoon or Hurricane Typhoon has a maximum winds exceed 117 KPH. CLASSIFICATION OF CYCLONES Classification of cyclone according to synoptic scale 1. Polar cyclone (polar regions, vast) 2. Polar lows (polar regions, short)

3. Extratropical cyclone (mid-latitude cyclone) 4. Subtropical cyclone (between the equator and 50o N and S) Lifecycle of tropical cyclone Lifetime size

TROPICAL CYCLONE Tropical cyclone is non-frontal synoptic scale lowpressure system over tropical waters with organized convection (i.e. Thunderstorm activity) and cyclonic surface circulation. This low pressure creates violent storms that are characterised by winds over 100km/h and heavy rainfall. They have caused the loss of life on a number of occasions due to there intensity. TROPICAL CYCLONE LOCATION

TC has synoptic scales of 100’s km

Average number of typhoons in the different areas of the world

TROPICAL CYCLONE REGIONS OF FORMATION

TROPICAL CYCLONE TRACK

TROPICAL CYCLONES - Technical Hazard Sheet - Natural Disaster Profiles

The Hazard Tropical cyclones are among the most destructive natural phenomena. The impact from cyclones extends over a wide area, with strong winds and heavy rains. However, the greatest damage to life and property is not from the wind, but from secondary events such as storm surges, flooding, landslides and tornadoes.

Factors of Vulnerability Man made factors:

Settlement located in low lying coastal areas (direct impact); Poor building design, or construction; Insufficient lead time for warning and evacuation; Non compliance with evacuation procedures;

Inadequate shelter. Main causes of Morbidity and Mortality Direct Impact

Injuries, trauma, and asphyxiation due to entrapment are observed and result from building collapse and wind-strewn debris. Electrocution or drowning happen while securing property such as television antennas or boats.

Short and long term mental health effects are observed.

Indirect Impact

The impact of tropical cyclones on the transmission of communicable diseases is limited. Outbreaks of communicable diseases are rarely observed. Nonetheless, the risk for water borne disease and vector transmitted disease can be exacerbated: human exposure to disease vectors can be increased due to changes in the physical environment.

The impact on the health infrastructures and all lifeline systems is massive and can result in food shortages and interruption of basic public health services (water, etc).

In case of floods and sea surges, risks of drowning and water borne and vector borne disease increase.

VULNERABILITY OF CYCLONES Which Countries Get Hit The Most By Tropical Cyclones? By Jonathan BellesJuly 06 2016 06:00 PM EDTweather.com

These 10 countries have been hit the most by tropical cyclones worldwide since the beginning of the modern global satellite surveillance in 1970.

This list compiled by NOAA's Hurricane Research Division includes tropical depressions, tropical storms and all global naming variants of hurricanes including typhoons and cyclones.

10.) Cuba Hurricane season: June 1 - November 30, with most storms forming in September and October

Strongest hurricane: The 1924 Cuba Hurricane brought sustained winds of 165 mph to extreme west Cuba. Tobacco crops and fishing vessels were severely damaged, and 90 people lost their lives.

Most recent hurricane: Hurricane Sandy brought winds of 115 mph to eastern Cuba in 2012.

Cuba has recorded 79 hurricane landfalls since records began, and 15 hurricanes have made landfall since 1970.

9.) Madagascar Cyclone season: November 15 - April 30, with peak activity in February

Strongest cyclone: Very Intense Tropical Cyclone Gafilo made landfall on Madagascar in 2004 with sustained winds of 155 mph. Gafilo caused 237 deaths and $250 million in Madagascar.

Most recent cyclone: Very Intense Tropical Cyclone Hellen in 2014 was a formidable cyclone in the Mozambique Channel, but greatly weakened as it approached land. Damage was less than expected.

8.) Vietnam Typhoon season: Year Round

Strongest typhoon: Numerous typhoons have made landfall with winds of 115 mph including Lola in 1993, Zack in 1995, Agnes in 1984 and others.

Most recent typhoon: Typhoon Kalmaegi brought typhoon-force winds to the Philippines and China before making final landfall in northern Vietnam as a typhoon in 2014.

7.) Taiwan Typhoon season: Year Round

Strongest typhoon: Super Typhoon Joan in 1959 hit Taiwan with 185 mph sustained winds, and caused 11 deaths and $3 million in crop damage in Taiwan alone. Joan went on to make final landfall in China.

Most recent typhoon: Typhoon Dujuan made landfall in eastern Taiwan with winds of 115 mph in 2015.

(MORE: Hurricane Central)

6.) Australia Cyclone season: November to April

Strongest cyclone: Severe Tropical Cyclone Monica (2006) paralleled the coast of the Northern Territory and made landfall near Maningrida with winds of 180 mph. Several thousand square miles of forest was wiped out, but no injuries were reported.

Most recent cyclone: Tropical Cyclone Stan in 2016 had winds of 80 mph just before landfall.

5.) United States (including Hawaii) Hurricane Season: June 1 - November 30

Strongest Hurricane: The 1935 Labor Day Hurricane remains the strongest and most intense hurricane to make landfall in the U.S. Sustained winds were calculated to be about 185 mph at landfall in the Florida Keys and the western Florida Everglades.

Most recent hurricane: Hurricane Arthur in 2014 struck eastern North Carolina. Hurricane Loke passed through an unpopulated area of extreme western Hawaii in 2015.

There have been 63 hurricane landfalls in the U.S. since 1970. This number includes some storms that became extratropical before landfall but brought hurricane force winds to the coast.

4.) Mexico Hurricane Season: May 15 - November (East Pacific) or June 1 - November 30 (Atlantic/Caribbean)

Strongest Hurricane: Hurricanes Dean (2007), Anita (1977), and Janet (1955) all had landfall sustained wind speeds of 175 mph, which are the strongest from the Atlantic side of Mexico.

Most recent hurricane: Patricia made landfall in 2015 as the strongest hurricane landfall from Pacific side with 150 mph winds

3.) Japan Typhoon season: Year Round

Strongest typhoon: Typhoon Vera (1959) made landfall in southern Japan with winds of 160 mph.

Most recent typhoon: Typhoon Goni made landfall in southern Japan in August of 2015.

2.) Philippines Typhoon season: Year Round, peaking in May to November

Strongest typhoon: Super Typhoon Haiyan (Yolanda) ripped the central Philippines apart in 2013 with winds of 195 mph at landfall.

Most recent typhoon: Typhoon Melor (Nona) made numerous landfalls in the central Philippines in 2015, at times with winds up to 145 mph.

1.) China Typhoon season: Year Round

Strongest typhoon: Typhoon Rammasun made landfall in southern China with winds of 155-160 mph in 2014. Cora in 1966 may have had similar strength

Most recent typhoon: Typhoon Mujigae made landfall in southern China with winds of 130 mph in 2015.

There have been at least 127 typhoons that have made landfall in China since 1970.

REASONS WHY CYCLONE DO NOT FORM IN CERTAIN TROPICAL REGIONS Cold currents Without the Coriolis force, surface winds cannot gain sufficient rotation to converge and the low pressure of the disturbance cannot be maintained. Large values of vertical wind shear disrupt the formation of a tropical cyclone by interfering with the organization of deep convection around the cyclone center. ◦ Wind shear- refers to a change in wind speed or direction with height in the atmosphere

5. Mesocyclone (associated with tornado formation) 6. Tropical cyclone (tropics CYCLONE HAZARDS   

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high seas - large waves of up to 15 metres high are caused by the strong winds and are hazardous to shipping storm surge - a surge of water of up to several metres can cause extensive flooding and damage in coastal regions heavy rain - the tropical cyclone can pick up two billion tons of moisture per day and release it as rain. This also leads to extensive flooding - often well inland from where the tropical cyclone hit the coast tornadoes - tropical cyclones sometimes spawn many tornadoes as they hit land which can cause small areas of extreme wind damage

EFFECTS OF CYCLONES 1. Tropical cyclones out at sea cause large waves, heavy rain, and high winds, disrupting international shipping and, at times, causing shipwrecks. 2. Tropical cyclones stir up water, leaving a cool wake behind them, which causes the region to be less favourable for subsequent tropical cyclones. 3. On land, strong winds can damage or destroy vehicles, buildings, bridges, and other outside objects, turning loose debris into deadly flying projectiles. 4. The storm surge, is typically the worst effect from landfalling tropical cyclones, historically resulting in 90% of tropical cyclone deaths. 5. The broad rotation of a landfalling tropical cyclone, and vertical wind shear at its periphery, spawns tornadoes . 6. Tropical cyclones have been responsible for the deaths of about 1.9 million people worldwide. Large areas of standing water caused by flooding lead to infection, as well as contributing to mosquito-borne illnesses . 7. Tropical cyclones significantly interrupt infrastructure, leading to power outages, bridge destruction, and the hampering of reconstruction efforts.

BENEFICIAL EFFECTS OF CYCLONES

1. Bring precipitation. Rainfall increases groundwater and the water levels of dams that provide drinking water, irrigation water and power generation. 2. Rains mean water for plants. About 50% of our water supply comes from rainfall brought by tropical cyclones. 3. Decreases the level of pollutants. 4. Tropical cyclones also help maintain the global heat balance by moving warm, moist tropical air to the middle latitudes and polar regions . 5. The storm surge and winds of hurricanes may be destructive to human-made structures, but they also stir up the waters of coastal estuaries, which are typically important fish breeding locales. 6. Tropical cyclone destruction spurs redevelopment, greatly increasing local property values.

CLASSIFICATION OF CYCLONE Classification of cyclone according to synoptic scale 1. Polar cyclone (polar regions, vast) 2. Polar lows (polar regions, short) 3. Extratropical cyclone (mid-latitude cyclone) 4. Subtropical cyclone (between the equator and 50o N and S) 5. Mesocyclone (associated with tornado formation) 6. Tropical cyclone (tropics)