通过评估参加CMIP3计划的22个GCM在20世纪气候情景(20C3M)下中国地区雪水当量模拟能力的检验,挑选出模拟能力较好的模式,通过多模式集合方法,对SEARS的模拟结果进行集合,预估未来40a雪水当量在中国地区的时空变化特征.结果表明:在A1B情景下和B1情景下,中国地区未来40a雪水当量年际变化均呈减少趋势;在A1B和B1情景下,青藏高原地区、华北平原地区、长江中游地区及东北北部地区的雪水当量均呈减少趋势,其中在昆仑山西段帕米尔高原地区减少最为显著,其次为喜马拉雅山区和巴颜喀拉山东段地区.在中国北部的内蒙古高原地区、云贵高原等部分地区的雪水当量则有所增加.总体上,A1B情景下比B1情景下雪水当量的减少更为明显.2021-2050年雪水当量在青藏高原减少显著;对于季节变化来说,在秋冬季积雪的累积期,雪水当量可能增加,尤其在10-12月,而在积雪消融的春夏季(2-6月)有所减少.
In the Coupled Model Intercomparison Project(CMIP3) there are 22 global climate models(GCM),of which the simulating capability on snow water equivalent(SWE) over China is tested in this paper.Those models having better simulating capability are chosen to predict the snow water equivalent in the coming 40 years over China.The results show that SWE will decrease in the coming 40 years over China for two scenarios(A1B and B1).It is found that there are SWE decreasing zones mainly in Tibetan Plateau,North China Plain,the middle reaches of Yangtze River and the north of Northeast China.Among them,the most significant decreasing zones are the Pamirs and the west of Kunlun Mountains,followed by the Himalayas and the east of Bayan Har Mountains.There is a slight increase of SWE in Inner Mongolia,the south of Yunnan-Guizhou Plateau and some other zones.Additionally,the decreasing rate in Scenarios A1B is greater than that in Scenarios B1.SWE will significantly decrease in 2021-2050 over the Tibetan Plateau.In autumn and winter,with snow cover increasing,SWE has a slight increase,especially from October to December,but in spring and summer,when snow cover disappears,SWE has a decrease.