Evaluation of MODIS land surface temperature with in-situ snow surface temperature from CREST-SAFE

Several trends in the MODIS LST data were observed, including the underestimation of daytime values and night-time values. Results indicate that although all the data sets Terra and Aqua, diurnal and nocturnal showed high correlation with ground measurements, day values yielded slightly higher accuracy about 1°C, both suggesting that MODIS LST retrievals are reliable for similar land-cover classes and atmospheric conditions. Increasing the MODIS window size showed an overestimation of in-situ LST and some improvement in the daytime Terra and night-time Aqua biases, with the highest accuracy achieved with the 5 × 5 window. A comparison between MODIS emissivity from bands 31, 32, and in-situ emissivity showed that emissivity errors relative error = −0.30% were insignificant.