【作者】 徐娟娟； 王可丽； 江灏； 孙佳； 雒新萍； 朱庆亮；

【Author】 Xu Juanjuan;Wang Keli;Jiang Hao;Sun Jia;Luo Xinping;Zhu Qingliang;Laboratory for Climate Environment and Disasters of Western China,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences;Graduate University of Chinese Academy of Science;

【机构】 中国科学院寒区旱区环境与工程研究所西部气候环境与灾害实验室； 中国科学院研究生院；

【摘要】 利用新一代中尺度天气模式WRFV2,2,通过敏感性试验讨论了黑河流域南部祁连山地形对黑河流域降水的影响。通过对地形去除前后近地面环流、水汽条件和垂直上升运动的对比分析,得出以下主要结论:黑河流域南部祁连山区的高大地形是影响黑河流域降水最主要的原因,若无祁连山区的地形作用,则黑河流域降水会基本消失;地形对黑河流域降水的影响方式为:西风带受祁连山地形阻挡而形成南北两支绕流,北支绕流于祁连山东侧边缘产生逆向东风,在地形与环流的共同作用下,99°E以东祁连山区地势较低处逆向东风辐合,从而导致此处水汽大量汇聚辐合堆积,同时地形的阻挡激发出强烈的对流运动,强的水汽辐合和强烈的对流运动的共同作用导致了祁连山区强降水的发生。更多还原

【Abstract】 Sensitivity simulations for the effects of the Qilian Mountain topography on the precipitation of the Heihe hasin were conducted hy using the new generation mesoscale weather model WRF(Weather Research and Forecast model) version2.2.According to analysis the changes of near surface circulation,moisture condition and upward motion after flattening the Qilian Mountain,conclusions are shown:①The topographic influence of Qilian Mountain is the main reason for the precipitation over Heihe River hasin:precipitation almost disappeared after flattening the Qilian Mountain topography;② The way that how the Qilian Mountain topography influence the precipitation over Heihe River hasin was as follows:The eastward near surface flow was split into two hraches hy the Qilian Mountain blocking,and then a significant westward turning occurred at eastern edge of the Qilian Mountain when the north hranch flow approached the north side of Qilian Mountain.The interaction hetween the flow and mountain topography made the deflecting westward flow converge at low terrain area of the east of 99°E of Qilian Mountain,which resulted in the greatly moisture converging here.At the same time,the topography hlocking leads to strong upward motion at eastern Qilian Mountain.Great moisture convergence and strong upward motion caused the heavy rain occurring in the Qilian Mountain area.更多还原