Validation of MODIS Land Surface Temperature Products in East of the Qinghai-Xizang Plateau
In order to validate the Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) products in the east of the Qinghai-Xizang plateau, the ground observation data of Litang Atmospheric Boundary Layer Observation Station are used.The accuracy of the ground-based surface temperature and its influencing factors are also analyzed.The results show that the surface radiometric temperatures (Tr) measured by the thermal infrared thermometer are lower up to 1.9 K during daytime and 1.1 K during nighttime than the surface temperatures (Ts_R) in account of the surface emissivity and atmospheric downward radiation.The deviations decrease with surface emissivity and increase with net long-wave radiation.The absolute errors between Ts_R and the surface temperature estimated using long-wave radiations (Ts_L) concentrate in less than 2.5 K when Ts_L are lower than 285 K, but reach up tol0K when Ts_L are higher than 285K.If the surface emissivity error is less than 0.01, the surface temperature calculation error is less than 0.5 K.Tr, Ts_R and Ts_L are significantly positively correlated with LST and the correlation coefficients between Ts_L and LST are biggest.The coefficients are larger during nighttime than daytime, while are larger for Terra than Aqua, particularly during daytime.The regression model of Ts_L based on the LST has a standard error of 4.4904 K and passes the 99% confidence level.
MODISLand surface temperatureValidationThe east of the Qinghai-Xizang Plateau