1960—2009年青海湖水位波动的气候成因探讨及其未来趋势预测

Cause of Water Level Fluctuation in Qinghai Lake from 1960 to 2009 and Its Future Trend Forecasting

利用近50 a来青海湖流域水文、气象资料和2010—2020年区域气候模式系统PRECIS输出数据降尺度生成的未来气候情景资料,揭示了1960—2009年青海湖水位波动的气候成因,预测了未来10 a青海湖水位可能变化趋势。研究表明:近50 a来青海湖水位在波动中呈持续下降趋势,而近5 a持续上升为近50 a来首次出现,不仅使水位持续下降趋势趋缓,同时使水位变化的短周期趋弱而较长周期趋强;青藏高原季风增强使青海湖流域气候暖湿化,而降水量增加和气温升高则使入湖径流量增加,进而引起了青海湖水位近5 a来的持续上升;据综合统计方法预测和区域气候模式系统PRECIS预测结果,2010—2020年青海湖水位总体上仍可能以下降为主。

The hydrological and meteorological data of Qinghai Lake in recent 50 years and future climate scenarios from regional climate model（PRECIS） during 2010-2020 are used.The cause of water level fluctuation is revealed from 1960 to 2009 and possible trend in the future 10 years is forecasted.It is found that the level shows a continued decline trend in fluctuation during the past 50 years,but continued rising in recent five years occurs for the first time in the 50 years.Based on which,the decline trend of water level becomes slow,the short cycle weakens and the long cycle intensifies;the Qinghai-Tibet Plateau monsoon makes the climate of the Qinghai Lake Basin warm and humid,but the increasing precipitation and rising temperature cause runoff into the lake increased,hence leading to the water level of the Qinghai Lake rising continuously in recent five years.The prediction results of combined statistical methods and regional climate model PRECIS indicate that water level of the Qinghai Lake is likely to drop generally during 2010-2020.