中国南方地区持续性暴雨特征及其影响因子分析  

Analysis of Characteristics and Influencing Factors of Persistent Rainstorm in Southern China

作　　者：于虹 周朝荣 张海涛 YU Hong;ZHOU Chao-rong;ZHANG Hai-tao(Electric Power Research Institute,Yunnan Power Grid Co.,Ltd.,Kunming 650217,China;Wenshan Power Supply Bureau,Yunnan Power Grid Co.,Ltd.,Wenshan 663000,China;Lincang Power Supply Bureau,Yunnan Power Grid Co.,Ltd.,Lincang 677000,China)

机构地区：[1]云南电网有限责任公司电力科学研究院,云南昆明650217 [2]云南电网有限责任公司文山供电局,云南文山663000 [3]云南电网有限责任公司临沧供电局,云南临沧677000

出　　处：《水电能源科学》2024年第12期28-31,121,共5页Water Resources and Power

摘　　要：以中国南方5省持续性暴雨为例,通过改进的区域持续性暴雨的定义,基于气象站点观测资料,找出我国南方地区持续性暴雨事件,并分析其特征及可能的影响因子。结果表明,南方地区持续性暴雨事件主要发生在每年的5~8月,通常持续3~5 d,主要集中在广东省、广西及贵州省南部,并且其影响范围呈显著增加趋势;同期西北太平洋海温与南方地区暴雨日数呈显著正相关关系,构建西北太平洋海温指数,并将同期大气环流与海温指数进行回归,发现当西北太平洋海温偏高时,西太副高偏弱,同时,贝加尔湖北部500 hPa位势高度正异常,其环流维持850 hPa异常北风输送至南方地区,使得南方地区水汽辐合、大气上升运动增加,易导致暴雨发生,海温异常高低年份的大气环流合成分析进一步证实了这种环流异常。Based on the persistent rainstorm events in five southern provinces of China,this paper identified the persistent rainstorm events in southern China using meteorological station observation data and an improved definition of regional persistent rainstorm,and analyzed their characteristics and potential influencing factors.The results indicate that the persistent rainstorm events in the southern region of China predominantly occurred from May to August each year.The event locations were mainly concentrated in Guangdong,Guangxi,and the southern part of Guizhou.The majority of these events lasted for 3 to 5 days.Notably,there was a significant increasing trend in the affected area over time.The northwestern Pacific sea surface temperature(SST)and rainstorm in southern China is significant positive correlation.The northwestern Pacific SST index was established.Regression analysis of the index and contemporaneous atmospheric circulation revealed that when the northwestern Pacific SST is anomalously high,a positive anomaly in 500 hPa geopoten-tial height over the northern part of Lake Baikal and anomalous northward winds at 850 hPa influence southern China.These atmospheric conditions enhance upward motion in the southern region,increasing the likelihood of persistent rainstorm events.Further confirmation of this anomalous circulation pattern was obtained through composite analysis of extreme years using the index.

关 键 词：南方地区 区域持续性暴雨 影响因子 西北太平洋海温 环流异常 

分 类 号：TV125[水利工程—水文学及水资源] P461[天文地球—大气科学及气象学]