长江流域2022年夏季高温过程的成因分析  

Causes of the high temperature process in the Yangtze River Basin in 2022

作　　者：张灵[1] 郭广芬[1] 熊开国 秦鹏程[1] 吴瑶[1] ZHANG Ling;GUO Guangfen;XIONG Kaiguo;QIN Pengcheng;WU Yao(Wuhan Regional Climate Center,Wuhan 430074,China)

机构地区：[1]武汉区域气候中心,武汉430074

出　　处：《地理科学进展》2023年第5期971-981,共11页Progress in Geography

基　　金：中国气象局复盘总结专项(FPZJ2023-082);湖北省自然科学基金项目(2022CFD014);长江流域气象开放基金项目(CJLY2022Y07);中国气象局创新发展专项(CXFZ2021Z033);湖北省烟草公司科技项目(027Y2022-006)。

摘　　要：长江流域2022年夏季遭遇了罕见的持续性高温事件,给流域各省生活、生产等造成了严重的影响,因此,科学解析该次高温过程成因对于提升高温过程预测预警具有重要意义。论文利用NCEP/NCAR逐日再分析资料和长江流域699个站点逐日温度资料,研究了2022年夏季长江流域高温过程的环流特征及成因。结果表明:①2022年长江流域的夏季高温过程为1961年以来范围最广、强度最强、持续时间最久、综合强度指数排名第一的高温事件。②长江流域上空对流层中高层受相当正压结构的异常反气旋环流控制,是此次高温过程发生的局地环流成因。南亚高压和西太平洋副热带高压的相向运动,且在长江流域上空重叠,是导致2022年高温发生的大尺度环流成因。在高压控制下,长江流域上空的下沉运动及达地面的太阳辐射均明显偏强,下沉增温和辐射增温共同导致高温极端性强。③欧洲西部经贝加尔湖向东频散的Rossby波能量,使得欧亚地区中高纬自西向东维持两脊一槽波列分布,北半球中高纬度表现出稳定的三波型,整个副热带地区为能量辐合区,助力副高维持偏强,同时有助于长江流域上空反气旋的持续,是异常环流长时间维持的原因。A rare persistent high temperature event occurred in the Yangtze River Basin in summer 2022,which caused serious impacts on the life and production of the provinces in the basin.Scientific analysis of the causes of this high temperature process is of great significance for improving the prediction and early warning of high temperature processes.Based on the NCEP/NCAR reanalysis data and the daily temperature data collected from 699 stations in the Yangtze River Basin,this study examined the atmospheric circulation characteristics and the causes of this high temperature process.The findings indicate that:1)The high temperature process that occurred in the Yangtze River Basin in 2022 ranked the highest in terms of the area of influence,intensity,duration,and comprehensive strength since 1961.2)There were mainly two circulation causes that attributed to this high temperature process.The first was the impact of local circulation,that is,the middle and upper layers of the troposphere over the Yangtze River Basin was controlled by the abnormal anticyclonic circulation generated by the equivalent barotropic mechanism.The second was the impact of large-scale circulation,that is,the South Asia High and Western Pacific Subtropical High moved in an opposite direction and overlapped over the Yangtze River Basin.Under the control of high pressure,the sinking movement over the Yangtze River Basin and the solar radiation reaching the ground are obviously strong,which led to strong extreme high temperature.3)The main reason for the long duration of the abnormal circulation is that with the Rossby wave transmitting energy eastward from Western Europe and the Lake Baikal,the circulation distribution presented a"two grooves and one ridge"model from west to east in the middle and high latitude of Eurasia and a stable"three-wave"model in the middle and high latitudes in the northern hemisphere.Therefore,the energy converged in the subtropical region above the Yangtze River Basin,which helped maintain the intensity of the subtropical

关 键 词：高温事件 成因分析 波能量 异常环流 长江流域 

分 类 号：P423[天文地球—大气科学及气象学]