中国西部积雪日数类型划分及与卫星遥感结果的比较

Classification of Snow Cover Days and Comparing with Satellite Remote Sensing Data in West China

根据中国105°E以西地区232个地面气象台站1951-2004年积雪日数观测资料和1980-2004年SMMR、SSM/I逐日雪深资料,划分中国西部积雪类型并分析其年代际变化,并对两种资料的结果进行了比较.结果表明:北疆、天山和青藏高原东部地区年平均积雪日数大于60d,为稳定积雪区;南疆盆地中心、四川盆地和云南省南部无积雪;其他地区为不稳定积雪区.北疆、天山、河西走廊以及成都、昆明一线广大地区积雪类型稳定少变,有、无积雪区的南北分界线在20世纪80年代达到最南位置.在中国西部,卫星遥感比地面台站观测的积雪日数总体偏多,主要体现在海拔较高的山区和河西走廊.

Based on the observed data of snow cover days of 232 weather stations from 1951 to 2004 and the daily snow depth data of SMMR and SSM/I during the period from 1980 to 2004 in West China,classification and decadal variations of snow cover days are analyzed.The results from the two kinds of data are compared as well.It is found that North Xinjiang,Tianshan Mountains and the east of Tibetan Plateau,with over 60 snow cover days,are the regions of stable seasonal snow cover.Regions without snow cover include the center of Tarim Basin,Sichuan Basin and the South Yunnan Province.In addition to the above-mentioned,there are unstable seasonal snow cover regions in West China.The classification of snow cover in the North Xinjiang,Tianshan Mountains,Hexi Corridor and the most area from Chengdu to Kunming are unchanged.The boundary between the areas with and without snow cover advanced to the most south position in the 1980s.Compared with the data of observation,the satellite remote sensing data show a little more snow cover days in West China,mainly in the high altitude mountains and Hexi Corridor.