ALGORITHMS FOR DETERMINATION OF LAND-SURFACE TEMPERATURES AND EMISSIVITIES FROM SATELLITE RADIATIVE MEASUREMENTS

Deriving LST from satellite radiative measurements is desirable, but t he accurate determination of LST is very difficult, which is related t o the atmospheric effect, the nonuniformity of land surface and the co upling between surface temperature and emissivity. In particular, the coupling between the land surface temperature and emissivity construct s a severe obstacle for the accurate determination of LST, because at present, the knowledge about global and surface emissivity is still ve ry deficient. Based on the assumption that the change of emissivity is normally negligible in a short period of time a two-channel method is proposed to determine LSTs and emissivities, simultaneously, in which a set of measurement data of two channels made at two different time, day and night or two continuous days or nights, are used. If there ar e emissivity variations in two time measurements, with the relative ch anges of emissivities for different channels being the same, then a th ree-channel method can be used to determine land surface temperature a nd emssivity simultaneously.