崇测冰帽冰芯记录与塔克拉玛干周缘观测的相逆降水趋势——兼论大气尘埃含量对高海拔山地冰川物质平衡的贡献

对钻自西昆仑山崇测冰帽6530m处18.7m长冰芯的分析得到:尘埃含量的变化影响着崇测冰帽钻点处的物质平衡———与其它气溶胶相比,沙尘微粒是冰帽钻点处降雪的主要贡献因子;以沙尘作为冰核的降雪是钻点处降水的主导形式。与塔克拉玛干沙漠周缘地区地面观测资料比较显示:近60a来的冰芯积累量所反映出的冰帽降水量在减少,同时显示塔克拉玛干沙漠周缘地区暖季降水量在增加,而沙尘恰是连接沙漠周缘地区和附近冰川区气候变化的中介。值得注意的是,本研究对于崇测冰帽冰芯中降雪积累率与尘埃沉降通量一致降低的发现具有区域范围,甚至全球范围气候变化的意义。

Opposite Trend of Ice Core Records from West Kunlun Mts. to Precipitation Region around Taklimakan Desert, China ——Contribution of air burden fine dust to the mass balance of high mountainous glaciers

A 18.7m long ice core drilled from 6530m a.s.l.of West Kunlun Mts.South of Taklimakan Desert was analyzed.Dust concentration records implied that: the quantitative change of fine dust effected the mass balance of Chongce Ice Cap,i.e.On the one hand,fine dust played a vital role in aerosols to contribute to the precipitation.On the other hand,fine dust,as CIN(cloud ice nuclei) dominanted the precipitation of Chongce Ice Cap.Comparing with observation data from the region around Taklimakan Desert,the result suggested that the trend of precipitation for Chongce Ice Cap in warm season was declining,while for the region around Taklimakan Desert was rising during the past 60 years.In addition,Fine dust was just the medium of climate change between the region around Taklimakan Desert and Chongce Ice Cap.Last but not the least,this observation of coherent decrease of snow accumulation rate and dust deposit in annum recorded in ice core from Chongce was a regional,even a global climate change.