近10 a浙江省极端短时强降水时空特征分析  

Spatio-temporal characteristics of short-duration extreme rainfall in the recent ten years in Zhejiang Province

作　　者：陶局 唐燕玲 易笑园[3] 张卫斌 许皓皓 TAO Ju;TANG Yanling;YI Xiaoyuan;ZHANG Weibin;XU Haohao(Zhejiang Ningbo Meteorological safety technology center,Ningbo 315012;Zhejiang Ningbo Meteorological Service Center,Ningbo 315012;Tianjin Meteorological Observatory,Tianjin 300074;Zhejiang Meteorological safety technology center,Hangzhou 310000;Zhejiang Ningbo meteorological network and equipment support center,Ningbo 315012)

机构地区：[1]浙江省宁波市气象安全技术中心,宁波315012 [2]浙江省宁波市气象服务中心,宁波315012 [3]天津市气象台,天津300074 [4]浙江省气象安全技术中心,杭州310000 [5]浙江省宁波市气象网络与装备保障中心,宁波315012

出　　处：《暴雨灾害》2021年第6期599-607,共9页Torrential Rain and Disasters

基　　金：浙江省气象局科技计划青年项目(2020QN17);宁波市气象局一般项目(NBQX2019007B)。

摘　　要：利用2010—2019年自动气象观测站逐小时降水资料,分析了近10 a浙江省极端短时强降水(1 h雨量≥50 mm或3 h雨量≥100 mm的降水)的时空分布特征,结果表明:(1)浙江省每年约有极端短时强降水169.8 h,主要分布在暖季(5—10月)及午后(14—21时),东部沿海(包括东南沿海和杭州湾)是高发带。(2)极端短时强降水主要始于5月,由浙南逐渐向浙北伸展,7—9月对应站点基本覆盖全境,而8月影响范围最大,对应有站点逐月年均频数峰值1.3 h·a^(-1),位于东南沿海,月平均强度峰值99.1 mm·h^(-1),位于杭州湾,10月及以后降水向东部沿海收缩,过程趋于结束。(3)极端短时强降水午后高发且强度增大,影响范围最广,并在17时有年均频数日变化曲线峰值,达17.4 h·a^(-1),同时午后东南沿海高频站点密集,占全省高频站数的83.2%,杭州湾降水强度增加,50%以上的站点超过57.6 mm·h^(-1)。(4)地形地貌与极端短时强降水的空间分布关系密切,东南沿海处的海陆交界下垫面及喇叭口地形有助于极端短时强降水的发生,而杭州湾洋面向内陆伸展的喇叭口地貌对降水效率的提高有促进作用。By using hourly precipitation data from the automatic weather stations in Zhejiang Province from 2010 to 2019,the temporal and spatial distribution of SDER(short-duration extreme rainfall,precipitation≥50 mm·h^(-1)or 100 mm·(3 h)^(-1))are studied.Several results are followed.(1)There are about 169.8 h per year of SDER in Zhejiang Province,mainly distributed in warm season(from May to October)and afternoon(from 14∶00 BT to 21∶00 BT).The eastern coast is a high incidence zone,including two areas:the southeast coast and Hangzhou Bay.(2)SDER appears from May and gradually extends from south to north.The corresponding stations basically cover the whole territory from July to September,and the most influential period is in August with monthly average peak frequency 1.3 h·a^(-1)for stations in southeast coast and monthly average peak intensity 99.1 mm·h^(-1)for stations in Hangzhou Bay.SDER moves eastward to the sea from October and the process gradually ends.(3)High incidence and intensity of SDER are mostly in the afternoon,with the scope of influence reaching the maxi⁃mum and the daily variation curve of annual frequency also arriving the peak value 17.4 h·a^(-1)at 17:00 BT.During this period,high-frequen⁃cy stations are concentrated at southeast coast,accounting for 83.2%of the total,while the precipitation intensity in Hangzhou Bay increases significantly,and more than 50%of the stations have exceeded 57.6 mm·h-1.(4)Topography is highly related to the spatial distribution of SDER.The underlying surface and trumpet-shaped topography of the sea-land interface in the southeast coast contribute to the occurrence of SDER,while the trumpet-shaped landform extending inland in Hangzhou Bay promotes the precipitation efficiency.

关 键 词：极端短时强降水 时空分布 季内变化 日变化 地形地貌 

分 类 号：P426.6[天文地球—大气科学及气象学]