国产综合在线观看视频,国产精品原创视频,亚洲国产熟亚洲女视频,一级风流片a级国产

關(guān)鍵詞: 北疆, 積雪, 穩定積雪, 最大積雪深度, 趨勢

Abstract: Based on the meteorological observations at 20 representative stations in Northern Xinjiang in 1961-2006, trends of snow cover (including the maximum depth, days of snow cover and steady snow cover) were investigated using the methods of autoregressive moving average model, second order principal value function, and correlation analysis. The results show that the maximum depth of snow cover was significantly positively correlated with winter precipitation; the maximum depth increased at an average annual growth rate of 0.8% in the past 46 years, which was smaller than that of winter precipitation. The day numbers of snow cover and steady snow cover were also significantly positively correlated with days of temperature steadily below 0℃, but the increasing trend of snow cover days was not significant; the days of snow cover increased from the 1960s to the 1980s, but decreased after the 1990s.

Key words: Northern Xinjiang, snow cover, steady snow cover, maximum depth of snow cover, multi-year variations, tendency