COMPARISONS OF THREE SINGLE-CHANNEL ALGORITHMS FOR RETRIEVING LAND SURFACE TEMPERATURE FROM HJ-1B SATELLITE DATA

HJ-1B Infrared Scanner (IRS) has accumulated long-term data, but there are no comparative studies on land surface temperature (LST) inversion algorithms for IRS data. This study compared the radiative transfer equation (RTE) and two generalized single-channel algorithms (GSC(w) and GSC(w)T) for retrieving LST from IRS data. Firstly, the coefficients of the GSC(w) and the GSC(w)T algorithms were simulated using MODTRAN 5.2 and the TIGR atmospheric profiles. ERA5 atmospheric profiles were used for the RTE algorithm. Second, land surface emissivity was calculated using the ASTER global emissivity dataset and vegetation/snow cover products based on the vegetation cover method. Finally, the LST retrievals were evaluated using ground measurements of twelve sites during the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) experiment from June 2012 to June 2014. The results showed that the accuracy of the RTE with bias (RMSE) of 0.74 K (2.47 K) is superior to the accuracy of the GSC(w)T with bias (RMSE) of -1.18 K (2.50 K), followed by the GSC(w) with bias (RMSE) of 1.60 K (2.77 K). The results can support the production of HJ-1B/IRS LST products.