【摘要】 文中从天气气候背景及天气学、动力诊断等方面 ,分析 2 0 0 0年秋、冬季河西大风和沙尘暴天气的形成原因 ,分析结果表明 ,几次大风、沙尘暴过程都是在高空 5 0 0hPa环流形势由纬向环流向径向环流调整的过程中 ,西西伯利亚强冷空气沿西北气流迅速南下 ,在蒙古地面热低压强烈发展的有利的热力和动力条件下发生的。同时 ,今年秋、冬季河西气温明显偏高 ,降水偏少以及河西地区特殊的地理环境 ,加剧了大风和沙尘暴天气的出现频次和强度。通过分析 ,初步总结出了此类天气的预报着眼点。更多还原

【Abstract】 The cause of formation of the gale and sandstorm in atumun-winter of 2000 in Gansu Corridor analysed by the weather and climate background,synoptics and dynamic diagnose.The result shows that several gale and sandstorm events occur on the advantaged dynamic and thermodynamic conditions of upper-air pattern adjusting from zonal circulation to meridional circulation on the 500hPa,west Siberian strong cold air rapidly moving southwardly and the heat low in Mongolia powerfully development.Meanwhile,the warm and dry in autumn-winter is favorable for the gale and sandstorm generation.Finally,the focus of prediction for such weather is summarized.更多还原