近50年来黑河出山径流对气候变化的响应

以黑河上游祁连山区祁连和野牛沟气象站逐月气象数据为基础,采用相关分析、多元回归模型、方差分析和时间幂函数的趋势分析等方法,研究了近50 a来影响黑河出山径流的主要气象因素。气象因子与径流的相关分析表明,冬季和夏季降水量、夏季和秋季月平均最低气温这4个气象因子与出山径流的相关系数最高,可以通过这4个气象因子建立多元回归模型模拟黑河出山年径流的变化。其中夏季降水对年径流的贡献最大,夏季和秋季月平均最低气温对年径流的贡献较小,年径流量变化主要受控于夏季降水量的强弱。时间幂函数的趋势分析结果进一步证实,黑河出山径流与夏季降水在年代际尺度变化的过程中具有很好的一致性。

Variations of Runoff in Responding to Climate Change in Mountainous Areas of Heihe River During Last 50 Years

Monthly meteorological data were obtained from typical weather stations located in the upper Heihe River.The influences of climatic factors on the runoff of the river from the mountain areas in the last 50 years were investigated using correlation,multivariate regression,analysis of variance,and trend analysis.The results of correlation show that winter and summer precipitation,summer and autumn mean lowest air temperature had close correlation with the runoff volume.Based on the close relationship,multivariate regression models were then developed to simulate the temporal variations of the runoff from the mountain areas.However,summer mean lowest air temperature showed little contribution to the runoff based on the regression analysis.The annual variations of the runoff were controlled by the precipitation amount in summer.Trend analysis results further confirmed that the runoff varied consistently corresponding to the summer precipitation over time scales of decades.