摘要
利用NCEP 1°×1°的6 h再分析资料等,对2010年8月14日开封市一次区域暴雨天气过程进行综合分析,结果表明:此次过程是在贝加尔湖附近高空冷低压东移南下,伴随高空横槽转竖,引起华北切变线加强,地面倒槽北侧冷空气南下,饱和暖湿气流被迫抬升凝结而致暴雨.暴雨的水汽供应主要来自对流层中低层,强水汽辐合出现在华北切变线附近和强降水前,与暴雨区相对应.地面倒槽附近的上升气流与切变线附近的上升气流叠加,与副热带高压中心内部的下沉气流构成了经向闭合环流圈,为暴雨天气的出现提供了强上升气流.高层辐散、低层辐合的大气垂直结构增强了大气的抽吸作用,促进垂直上升运动的发展.
In this paper, using NCEP 1°×1° 6 h reanalysis data in Kaifeng City on August 14, 2010, the appearance of a regional rainstorm process was analyzed. The results show that the high-altitude of the vicinity of Lake Baikal cold low moved southeast, with the upper transversal trough to vertical, leading to shear line strengthening in North China, cold air of the north side of the surface trough moving southward, saturation of warm air being forced to uplift and condense, and then due to rainstorm. Rain water supply was mainly from middle and low troposphere water vapor convergence in North China, near shear line and before strong precipitation,and corresponding to heavy rain area. The updraft superposition near sufrace and shear line, and the closed circulation constituted by the subtropical high internal downdraft,offered the strorg rising air currents for heavy rain. Atmospheric vertical structure of high level divergence, low level convergence enhances the air suction effect, and promotes the development of vertical movement.
出处
《河南科学》
2012年第8期1142-1145,共4页
Henan Science
基金
河南省气象科学研究项目资助(Z2007023)
关键词
暴雨
切变线
经向环流圈
垂直螺旋度
rain
shear line
meridional circulation
vertical helicity
