青藏高原积雪变化及其对中国水资源系统影响研究进展

Progresses in Variability of Snow Cover over the Qinghai-Tibetan Plateau and Its Impact on Water Resources in China

回顾了青藏高原(下称高原)积雪变化及其对中国水资源系统影响研究进展,探讨了开展高原积雪异常对中国水资源系统影响研究存在的不足和未来趋势。高原积雪分布极不均匀,呈四周山区多、腹地少,两侧多、中间少的空间分布特征。高原东部积雪变化最显著且主导了整个高原积雪的年际变化,因此该地区积雪异常更值得关注。自20世纪60年代以来高原积雪总体呈缓慢增加趋势,21世纪初期春季和冬季积雪略有减少。目前,关于高原积雪变化对我国水资源系统影响的研究主要集中在高原积雪异常对降水和旱涝影响及其预测指示性研究两方面。高原积雪主要通过季风影响我国的降水时空分布,进而影响水资源系统。高原积雪异常对我国降水影响大,且范围广,可作为降水预测的一个重要信号,同时其对我国旱涝分布具有重要影响,并且对旱涝预测具有指示意义。

The major advances in the researches on the variability of snowcover over the Qinghai-Tibetan Plateau（ QTP） and its impact on water resources in China are summarized. Some existing problems in the related studies and the researches needing further investigation are also discussed. The distribution of the snowcover over the QTP is far from uniformity. In the peripheral high mountains snowcover distributes extensively and has a long duration,but in the vast interior it is rare or even thin. The snowcover region in the east of QTP is the most significant region of the interannual variation of snowcover on the QTP,and dominates the interannual variation of snowcover in the whole plateau. So the snowanomalies over the eastern QTP should be paid more attention. The snowcover on the QTP increased from 1960 s to 1990 s,and its extent slowly increased in summer and autumn but decreased in winter and spring in the early 21 st century. The research progresses on the impact of snowcover over the QTP on water resources are focused on precipitation and drought-flood. The abnormal snowcover over the QTP can affect the atmospheric circulation and Asian summer monsoon precipitation in terms of changing ground surface albedo,temperature and thermal conditions. The impact of abnormal snowcover over the QTP on precipitation is high consequence and wide areas. The abnormality of snowcover over the QTP has certain influences on droughts and floods of China. The snowcover abnormality could be applied in drought and flood forecast,too.