Inversion of land surface temperature and emissivity simultaneously from multispectral thermal infrared imagery

Land surface temperature (LST) and emissivity are important variables in land surface modeling and longwave radiation budget calculation. The only practical means of obtaining LST at spatial and temporal resolutions appropriate for most modeling applications is through thermal infrared remote sensing. Multispectral thermal infrared imagery provide us with the excellent opportunity to estimate both LST and emissivity simultaneously, but the challenging issue is that a single multispectral thermal measurement with N bands presents N equations in N+1 unknowns (N spectral emissivities and LST). In this study, we developed a general algorithm that can separate land surface emissivity and LST from any multispectral thermal imagery, such as MODIS (Moderate-Resolution Imaging Spectroradiometer) and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer).