广西汛期极端短时强降水特征分析  

Analysis of characteristics of the extreme short-time heavy rainfall in Guangxi in rain season

作　　者：廖胜石 卓健 罗建英 零绍珑 卢炳夫 LIAO Shengshi;ZHUO Jian;LUO Jianying;Ling Shaolong;LU Bingfu(Guangxi Climate Center,Nanning 530022;Guangxi Meteorological Information Center,Nanning 530022;Guangxi Meteorological Bureau,Nanning 530022;Guigang Meteorological office of Guangxi,Guigang 537100;Gguagnxi Meteorological Disater Prevention Center,Nanning 530022)

机构地区：[1]广西壮族自治区气候中心,南宁530022 [2]广西壮族自治区气象信息中心,南宁530022 [3]广西壮族自治区气象局,南宁530022 [4]广西贵港市气象局,贵港537100 [5]广西壮族自治区气象灾害防御技术中心,南宁530022

出　　处：《暴雨灾害》2022年第3期308-314,共7页Torrential Rain and Disasters

基　　金：广西气象科研计划(桂气科2021M21,桂气科2022Z03)。

摘　　要：利用2005—2021年4—10月广西91个国家气象站小时降水数据和Oceanic Nino Index (ONI)数据,分析了广西汛期极端短时强降水的特征及其关联因子。结果表明:(1)广西超过80%站点的极端短时强降水强度在40~70 mm·h^(-1),强度和频次最高均出现在沿海地区,频次次高区域为桂东北地区,但其强度却为广西最低;(2)每年极端短时强降水频次呈现增多趋势,每年5、6月份极端短时强降水频次最高,但各个月份强度变化不大。(3)每日04—05时、17—18时的极端短时强降水频次最高,各个时次强度均在50~55 mm·h^(-1),差别不大。(4)广西极端短时强降水特征不仅与地形密切相关,而且与南海夏季风、厄尔尼诺/拉尼娜事件关联性很大。(5)前一年秋季的ONI和次年前汛期的极端短时强降水呈显著正相关。Based on the hourly precipitation data from 2005 to 2021 at the 91 meteorological stations and Oceanic Nino Index in Guangxi in rain season, the spatial and temporal distribution characteristics of extreme short-time heavy rainfall are analyzed. The results show that:(1)In most parts of Guangxi, the intensity of extreme short-time heavy rainfall ranges from 40 to 70 mm·h^(-1). The highest intensity and frequency of extreme heavy rain are seen in the coastal areas, while the lowest intensity is seen in northern inland regions with more frequent heavy rain.(2) The number of extreme short-time heavy rainfall per year continues to rise. In May and June, the frequency of these events is the highest and the little monthly change of the heavy rainfall intensity has been observed.(3) The diurnal variation curve of the incidence of extreme heavy precipitation appears to be bimodal with peaks during 04∶00 BT-05∶00 BT and 05∶00 BT-06∶00 BT. The intensity of this kind of rainfall varies from 50 to 55 mm per hour with little variation in amplitude in different hours.(4) The spatial distribution characteristics of extreme short-time heavy rainfall is not only closely related to the terrain features, but also associated with the South China Sea summer monsoon onset and El Nino/La Nina event.(5) It is shown that there is a positive correlation between the Oceanic Nino Index of previous autumn and the frequency of extreme short-time heavy rainfall.

关 键 词：极端短时强降水 南海夏季风 厄尔尼诺 拉尼娜 

分 类 号：P426.6[天文地球—大气科学及气象学]