Characterizing the Meso-Scale Enviromental Thermal Effects Due to Different Landuse Types using Remote Sensing Techniques and Indices in Taoyuan, North Taiwan

The purpose of this paper was to characterize the mesoscale environmental thermal effects due to different landuse types in Taoyuan, north Taiwan with the application of remote sensing techniques and indices. A LandSat 7 ETM+ image was utilized to characterize the spatial distribution of land surface temperature and the average temperatures of different land use types. Two remote sensing indices, Normalized Difference Vegetation Index (NDVI) and Normalized Difference Moisture Index (NDMI) were calculated in each pixel of the image and linearly regressed with the surface temperature. The results showed that the average land surface temperatures in urban area and bare land was 3.43degC and 2.58degC higher and those in grassland, forest, waterbody, and rice paddies was 0.78degC, 0.70degC, 2.79degC, and 2.87 degC lower than the overall average temperature. It was also found that the surface temperature reduced 1.3degC for every increment of 0.1 in the NDVI and reduced 1.7degC for that in the NDMI. It demonstrated that surface moisture content and vegetation coverage greatly influenced land surface temperature.