2022年夏季四川持续高温干旱特征及成因分析  

Characteristics and Mechanisms of Persistent High Temperature and Drought during Summer in 2022 in Sicuan

作　　者：高洁[1,2] 肖红茹 郭善云[1,2] GAO Jie;XIAO Hongru;GUO Shanyun(Sichuan Provincial Meteorological Observatory,Chengdu 610072,China;Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province,Chengdu 610072,China)

机构地区：[1]四川省气象台,四川成都610072 [2]高原与盆地暴雨旱涝灾害四川省重点实验室,四川成都610072

出　　处：《沙漠与绿洲气象》2023年第5期118-126,共9页Desert and Oasis Meteorology

基　　金：高原与盆地暴雨旱涝灾害四川省重点实验室科技发展基金项目(SCQXKJQN202306)。

摘　　要：利用1961—2022年四川155个国家气象站逐日气温、降水资料和NCEP/NCAR再分析资料等,对2022年四川持续高温干旱事件特征及成因进行分析。结果表明:2022年夏季四川出现极端高温干旱天气,全省平均气温、最高气温、高温日数均突破历史同期极值,73.0%的站点出现重旱及以上旱情,为1961年以来最严重高温伏旱天气气候事件。南亚高压北跳东进,异常偏强偏北,500 h Pa青藏高压发展东移,或西太平洋副热带高压加强西伸北抬,与南亚高压叠加,形成稳定正压结构控制四川,是造成高温干旱的主要原因。亚洲中纬度地区盛行纬向环流,伊朗高压、青藏高压和西太平洋副热带高压打通形成高压带,盛行下沉辐散气流,阻挡中高纬冷空气南下和低纬暖湿气流北上,导致四川地区降水异常偏少,是高温干旱的间接原因。Based on the daily temperature and precipitation data from 155 national meteorological stations in Sichuan province and NCEP/NCAR reanalysis data from 1961 to 2022,the characteristics of persistent high temperature and drought event during summer in 2022 and its mechanisms were analyzed.The results showed that the average temperature,maximum temperature and high-temperature days during summer in 2022 exceeded the maximum values of the historical corresponding period,with the value of 73.0%stations happened severe drought or above,implying a most serious high temperature and drought event since 1961.The direct reasons for this event were found that the enhancement and northward movement of the South Asia high(SAH)characterizing as jumping northward and advancing eastward,superimposed with the Tibetan high(TBH)at 500 hPa developing eastward or the western Pacific subtropical high(WPSH)strengthening to move northwestward,which finally formed a stable barotropic structure controlling the weather of SCP.In addition,the mid-latitude Asia prevailed zonal circulation,and the high pressure belt formed by the Iran high,TBH and WPSH prevailed sinking divergence air,which blocked the cold air from the mid-high latitudes moving southward as well as the warm moist air from the lower latitudes moving northward.This led to the decreased precipitation in SCP,resulting in a high temperature and drought event.

关 键 词：极端高温 干旱 四川 南亚高压 西太平洋副热带高压 

分 类 号：P423.3[天文地球—大气科学及气象学] P434