不同天气系统下海河流域汛期暴雨落区及时程分布规律

摘要

以1955-2007年海河流域降雨资料为基础,结合暴雨时的天气系统,利用GIS技术和统计方法分析了海河流域汛期暴雨落区及时程分布规律.结果表明:区域性或流域性暴雨中心位于滦河水系最多,永定河水系暴雨中心最少,且多伴随暴雨遭遇,又以相邻流域间暴雨遭遇为主;气旋是引起海河流域区域性暴雨或流域性暴雨最多的一种天气系统;天气系统对各水系间及流域内的暴雨遭遇没有明显影响;次暴雨过程以前、中期型为主,切变线、高空槽、蒙古气旋、东北气旋、黄河气旋天气系统的暴雨均是前期型最多,台风和江淮气旋天气系统的暴雨为中期型最多.%Based on the rainfall data in Haihe River Basin from 1955 to 2007, the distribution of rainstorm centers and processes under different weather systems was investigated by means of the GIS technology and the statistical methods.The results show that the rainstorm centers of the regional or basin-wide rainfall are mostly located in Luanhe River subbasin and the least in the Yongding River sub-basin. Rainstorms often happen simultaneously in different sub-basins,mainly in adjacent sub-basins. Cyclone most frequently causes the regional or basin-wide rainstorms in Haihe River Basin. The weather systems have no significant impacts on the coincidences of rainstorms happened among different subwatersheds as well as in the whole watershed. Most rainfall concentrates in the prior or middle periods. The antecedent type is the most happened rainstorm type for all kinds of heavy rain under weather systems of shear line, high-altitude trough, Mongolia cyclone, north-east cyclone, northeast cyclones and Yellow river cyclone. Both the weather systems of typhoons and Jianghuai cyclone give priority to the mid-term rainstorm type.