大兴安岭地区近31年积雪与冻土变化分析

利用1975～2005年大兴安岭地区6个气象台站的常规观测资料，分析了大兴安岭冬春积雪日数和最大冻土深度的变化及其与气候变化的关系。结果表明，大兴安岭冬春积雪日数在20世纪80年代略有增加，90年代减少；而近31年总体趋势呈减少趋势。近31年大兴安岭的最大冻土深度呈递减趋势。冬春积雪日数变化与冬春气温变化呈负相关，但与冬春降水之间没有明显的相关关系。最大冻土深度的变化与冬春气温和冬春降水的变化均呈负相关。

Variation Analysis of the Snow and Frozen Soil in Daxinganling Area during 31 Years

By using the observation data of 6 weather stations in Daxinganling Area from 1975 to 2005,the variation of winter-spring (from last October to this April) snow day and the maximum depth of frozen soil in Daxinganling Area and their correlation with climate changes were analyzed.The results showed that the days of winter-spring snow was increasing in 1980s and decreasing in 1990s.The overall trend of winter-spring snow days showed a decreasing trend in 31 years.The maximum depth of frozen soil was gradually decreasing in 31 years.The change of winter-spring snow days had a negative correlation with the temperature changes in winter-spring,but it had no obvious correlation with the precipitation in winter-spring.The changes of maximum depth of frozen soil showed negative correlations with the changes of temperature in winter-spring and precipitation in winter-spring.