河南“21·7”极端暴雨过程地形敏感性试验  

Topographic Sensitivity Test of“21·7”Extreme Rainstorm Process in Henan Province

作　　者：张启绍 ZHANG Qishao(Anyang National Climate Observatory,Anyang 455000,Henan China;China Meteorological Administration·Henan Key Laboratory of Agrometeorological Support and Applied Technique,Zhengzhou 450003,China;Anyang Meteorological Bureau,Anyang 455000,Henan China)

机构地区：[1]安阳国家气候观象台,河南安阳455000 [2]中国气象局·河南省农业气象保障与应用技术重点开放实验室,郑州450003 [3]安阳市气象局,河南安阳455000

出　　处：《河南科学》2023年第3期398-407,共10页Henan Science

基　　金：安阳国家气候观象台开放研究基金(AYNCOF202312);中国气象局·河南省农业气象保障与应用技术重点实验室项目(KM202223)。

摘　　要：使用FNL1°×1°再分析资料、高空和地面观测资料、多普勒雷达资料和卫星云图等资料,对2021年7月17—23日河南极端暴雨天气过程进行分析,采用WRF数值模式进行地形敏感性试验.分析结果表明,此次极端暴雨天气发生在稳定的大尺度大气环流背景下,对流层中低层的低涡、切变线以及中小尺度系统的不断生消是造成极端暴雨的直接原因;台风“烟花”的生成、发展和移动对暴雨区的水汽输送有着重要影响.地形敏感性试验结果表明:①将一定范围内的地形高度降低为0,会导致降水中心降水量减少,整体减幅20%~40%,同时会造成雨带西移1°E左右;②将固定范围内的地形高度降低时,会造成降水中心降水量减少,整体减幅10%~40%,地形高度降低大于或等于75%时,会导致雨带西移1°E左右;③将固定范围内的地形高度增加时,会导致降水中心降水量增大,整体增加10%~40%,地形高度增高50%以上会导致雨带东移1°E左右.IIn the paper,FNL1°×1°reanalysis data,high-altitude and ground observation data,Doppler radar data,satellite cloud images and other data are used to analyze the process of the extreme rainstorm that happened in Henan Province during July 17-23,2021.In addition,the WRF numerical model is used to conduct terrain sensitivity test.The results show that the extreme rainstorm occurred under the background of stable large-scale atmospheric circulation.The direct cause of the extreme rainstorm is the evolution of the low-level vortices,shear lines in the middle and lower troposphere and the continuous generation and extinction of the medium-small scale systems.The formation,development and movement of the severe typhoon“In-Fa”have an important influence on the transport of water vapor in extreme rainstorm area.The results of terrain sensitivity test show that:①Reducing the terrain height within a certain range to zero will lead to a reduction of precipitation in the precipitation center,with an overall decrease of 20%-40%,and will cause the rain belt to move westward by about 1°E.②When the terrain height within the fixed range is reduced by a uniform percentage,the precipitation in the precipitation center will decrease by 10%-40%.If the terrain height is reduced by 75%or more,the rain belt will move westward by about 1°E.③When the terrain height within the fixed range is increased by a uniform percentage,the precipitation in the precipitation center will increase by 10%-40%.If the terrain height is increased by 50%or more,the rain belt will move eastward by about 1°E.

关 键 词：WRF 暴雨 迎风坡 地形敏感性试验 

分 类 号：P458.121[天文地球—大气科学及气象学]