干旱区生态环境知识资源中心

In this study, two latest Collection 6 (C6) MODIS level-2 LST products (MxD11_L2 and MxD21_L2) from both the Terra and Aqua satellites were evaluated against ground measurements collected in an arid area of northwest China during the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) experiment. Ground measurements of four and a half years at four barren surface sites were used to carry out the evaluation, which took place from June 2012 to December 2016. The results show that the C6 MxD21 LST products demonstrate a better accuracy than C6 MxD11 LSTproducts both at daytime and nighttime for the four sites. For the daytime result, C6 MxD11 products underestimate the LST at the four barren surface sites, with an average bias of -1.77 K for Terra and -2.63 K for Aqua, while the average biases of MxD21 LST products are much smaller, with an average bias of 0.34 K for Terra and -0.67 K for Aqua, respectively. For the nighttime result, C6 MxD11 products also underestimate the LST at the four sites, with an average bias of -1.41 K for Terra and -1.01 K for Aqua, while the average biases of MxD21 LST products are 0.14 K for Terra and 0.54 K for Aqua, respectively.