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By using the observational snow data of more than 700 weather stations, the interannual temporal and spatial characteristics of seasonal snow cover in China were analyzed. The results show that northern Xinjiang, northeastern China-Inner Mongolia, and the southwestern and southern portions of Tibetan Plateau are three regions in China with high seasonal snow cover and also an interannual anomaly of snow cover. According to the trend of both the snow depth and snow cover days, there are three changing pattems for the seasonal snow cover:. The first type is that both snow depth and snow cover days simultaneously increase or decrease; this includes northern Xinjiang, middle and eastern Inner Mongolia, and so on. The second is that snow depth increases but snow cover days decrease; this type mainly locates in the eastern parts of the northeastern plain of China and the upper reaches of the Yangtze River. The last type is that snow depth decreases but snow cover days increase at the same time such as that in middle parts of Tibetan Plateau. Snow cover in China appears to have been having a slow increasing trend during the last 40 years. On the deeadal scale, snow depth and snow cover days slightly increased in the 1960s and then decreased in the 1970s; they again turn to increasing in the 1980s and persist into 1 990s.