Assignment Remote Sensing

ASSIGNMENT Remote Sensing Technology 1 (SGS 1633) Discuss the applications of the following satellite data, (a) Landsat Thematic Mapper (b)SPOT HRV

Landsat TM is the series of satellite that is well-known satellite for remote sensing and earth monitoring. Due to its band, we can differentiate the usage of each band. BAND 1 –for soil/vegetation discrimation, bathymetry/coastal mapping, cultural/urban feature identification. BAND 2 –for green vegetation mapping by measuring reflectance peak, cultural/urban feature identification. BAND 3 –for differentiate between vegetated and non vegetated area, plant species discrimination (plant chlorophyll absorption), cultural/urban feature identification BAND 4 –identification of plant/vegetation types, health and biomass content, water body delineation, soil moisture BAND 5 –Sensitive to moisture in soil and vegetation, discriminating snow, and cloud-covered areas. BAND 6 –Vegetation stress and soil moisture discrimination related to thermal radiation, thermal mapping. BAND 7 –Discrimination of mineral and rock types, sensitive to vegetation moisture content.

There are many application of Landsat TM satellite data such as for environmental monitoring applications of low spatial resolution images where this satellite data help in doing vegetation assessment. By combining certain band, you can differentiate the type of plant easier by using NDVI(Normalised Difference Vegetation Index). It is also used in topographic mapping and land cover mapping. The technique of false colour helping the researcher to easily study of land cover easily. False colour combination of bands 3(visible red), 4(near infrared) and 5(mid infrared) can also study health of vegetation. Landsat TM also useful in detecting the sea-surface temperature, algal blooms, estuarine sediment plumes, oil spill and other pollutant contamination plumes compared to SPOT

which is limitated because it has neither a thermal infrared band nor a blue visible band. Landsat TM also provide wealth of information for geological mapping and exploration. It is cost and time effective for larger project or difficult to access area.

SPOT HRV (High Resolution Visible) sensor operates in two modes, namely the Multispectral Mode and the Panchromatic Mode. Two identical HRV instruments with 3 VNIR bands and a ground resolution of 20 m can point in the cross-track direction up to 31 degrees from nadir. The swath width varies from 60 km (nadir) to 80 km when angled at the maximum limit from nadir. HRV panchromatic has spectral range between 500 nm and 730 nm (one channel) and 10 m spatial resolution. This is important in detail in complex and small region. Although it has fewer bands but its superior spatial resolution allowing individual faults and rock layer to be mapped. SPOT images as well as Landsat is also used to find areas of poor crop development in conjunction with accurate location information from GPS(Global Positioning Systems). So, farmer can focus supplying fertilizing activities on these areas only and not waste fertilizer on ares with good soil. SPOT has been found to be better than Landsat TM iat defining individuals field boundaries and small parcels of land of only a few hectares in size. We can also differentiate between vegetation using SPOT satellite. SPOT also important in agriculture especially for afforestation or reforestation protection, crop or plant Yields and forest fires. It also important in studying atmospheric Phenomenon such as cyclone, storm and hurricane.