LAUSR

Abstract In order to know how regional averaged cloud top height (CTH) responded to the past climatic change, the spatial and temporal variations of CTH based on MODIS data (MOD03_08_v6.0) from March 2000 to February 2018 are analyzed. The results show that the CTH in East Asia was higher in the southwest and lower in the northeast. The annual mean CTH was found to increase in East Asia at the rate of 0.020 km per year, of which, 0.035 km per year over the eastern land and 0.034 km per year over the eastern sea. The CTH changes statistically correlated with the sea surface temperature changes over the eastern sea (r = 0.68), which indicates that the CTH changes may be affected by the underlying surface. Statistically significant increasing trend of annual mean CTH was found in the latitude zone of 30°–40°N. Furthermore, CTH showed decreasing trends of about −0.030 km per year in the Middle-Lower Yangtze River Basin, Tarim Basin, Turpan Basin and northeastern Sichuan Basin in summer since more low cloud formations benefited to the decrease of CTH. In winter, the decreasing trend of CTH was found over the north of 40°N, whereas the increasing trend was found over the south of 40°N in East Asia.