Study on the Effects of Landcover Changes on Surface Albedo and Surface Temperature in Bangladesh Using Remote Sensing and GIS

摘要

Dynamic changes in Earth’s land cover characteristics and associated temporally evolving biophysical surface properties, as well as their ultimate impacts on surface radiative (surface albedo) and climatic properties (land surface temperature), have been studied. The study area includes a part of southwestern Bangladesh covering a period of about twenty years from 1988 – 2011. The widely used Surface Energy Balance Algorithm for Land (SEBAL) has been applied in conjunction with satellite-derived radiative measurements. Relatively important land use types such as water, soil, sand, settlement, shrimp farm, forest and agricultural crop have been considered. Feature type conversion of parameters i.e Normalized Difference of Vegetation Index (NDVI), surface albedo and land surface temperature have been noticed over the area under the present study. The highest surface albedo as well as surface temperature value has been noticed over the sandy area. Analysis revealed increases of surface temperature by about 1 °C and 3 °C for land cover conversion from (i) crop to settlement and (ii) water to soil, respectively. All other categories of landcover conversion generally experience decreases in surface temperature. Spatial vegetation coverage and amount of soil moisture play a dominant role in the radiative as well as climatic properties.