Effects of Atmospheric Water Vapor and Aerosol on Retrievals of Land Surface Temperature in Dunhuang Site
敦煌地区大气水汽和气溶胶对获取地表温度的影响

Radiometric calibration of satellite-acquired data (visible, near-infrared and thermal infrared) is essential for quantitative scientific studies, as well as for a variety of quantitative appications. In the spectral region of thermal infrared,the effects of atmospheric water vapor and aerosols on the retrievalsof surface temperature are the two primary factors. From Landsat-5 TM6 image data acquired at Dunhuang site on September 25 1995, we made adjustments for atmospheric effects and derived the land surface temperatures using the spectrally corrected LOWTRAN-7 code. Using LOWTRAN-7 code, we also analyse the effects of atmospheric water vapor and aerosols on the retrieved surface temperatures by simulative calculations. Finally, we provided an explanation for what kinds of atmospheric conditions, even without considering the foreknown influence of the atmosphere, properly calibrated thermal infrared data can provide accurate remote temperature measumments, and determined under what meteorologic conditions, making corrections for atmospheirc effects is in need. This paper, at the end, also discussed the emissivity effects on the derived surface temperature.