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Surface emissivity in the thermal infrared region is an important parameter for the studies of energy budget and surface energy balance. This paper focuses on estimating broadband emissivity using two sensors on NASA's Earth Observing System (EOS) Terra satellite, Advanced Spaceborne Thermal Emission and reflection Radiometer (ASTER) and MODerate resolution Imaging Spectrometer (MODIS). We developed a regression approach to generate infrared broadband emissivity maps from ASTER or MODIS data. The regressions are to relate the broadband emissivity to the emissivities for the ASTER or MODIS channels. The both regressions were calibrated using libraries of spectral emissivities.

We applied this approach for ASTER and MODIS data acquired over the North Africa and Australia. The range of the broadband emissivity was found to be between 0.86 and 0.96 for the desert area. The root mean difference between the emissivities from these two sensors is smaller than 0.015. Such emissivity map could be used as an input of climate model and could contribute for improving the simulated surface and air temperature up to 1.1 and 0.8 degrees C respectively. The method can be applied to any and regions of the world.