2023年夏季新疆高温的阶段性特征及环流演变  

Stage Characteristics and Circulation Evolution of the High Temperature in the Summer of 2023 in Xinjiang

作　　者：曹萌 刘精 陈颖 CAO Meng;LIU Jing;CHEN Ying(Xinjiang Uygur Autonomous Region Climate Center,Urumqi 830002,China)

机构地区：[1]新疆维吾尔自治区气候中心,新疆乌鲁木齐830002

出　　处：《沙漠与绿洲气象》2024年第5期113-119,共7页Desert and Oasis Meteorology

基　　金：中国气象局复盘总结专项(FPZJ2023-153)。

摘　　要：气候变暖背景下,2023年夏季新疆气温异常偏高,平均气温、高温日数、高温过程持续时间均居1961年以来同期第一位,且高温覆盖面积最广。针对本次高温的阶段性和极端性特征,利用新疆105个国家级气象站及NCEP/NCAR再分析等资料,分析其不同阶段对流层中高层环流演变规律。结果表明:100 hPa南亚高压偏东偏北且强度偏强,500 hPa伊朗副高持续加强东伸,西太副高加强西伸北扩且异常偏西偏强,两个层面的系统相互呼应,形成垂直高度的稳定正压结构,有利于气温偏高并长期维持,后期随着100 hPa南亚高压主体进入青藏高原上空,500 hPa伊朗副高西退,副热带高压带断裂,中亚地区对流层中高层的稳定结构瓦解,在新疆上游出现低压槽区,有利于冷空气自北方进入,造成阶段性降温天气,高温减弱。通过对极端高温过程的环流特征分析可知,新疆区域性极端高温过程与100 hPa南亚高压系统密切相关,尤其跟中心纬度位置显著正相关,当南亚高压主体在55°~90°E且中心面积偏大时,中心位置偏北有利于新疆区域性极端高温过程的发生。Against the backdrop of climate warming,the summer of 2023 witnessed unprecedentedly high temperatures in Xinjiang.The average temperature anomaly ranked highest since 1961,alongside the highest number of scorching days and high temperature days durations in recorded history.The coverage area of high temperatures was also the widest.In light of the stage and extreme characteristics of this high temperature,this study analyzed extreme features and the evolution law of the middle and high levels of the troposphere in different stages using data from 105 national meteorological stations in Xinjiang and NCEP/NCAR reanalysis data.Results revealed an eastern and northerly 100 hPa circulation field of the South Asian high,with intensified intensity.Additionally,the 500 hPa circulation field of the Iranian deputy high minister continued to strengthen and extend eastward,while the West Pacific subtropical high intensified and expanded westward and northward,with stronger anomalies.These systems cooperated,fostering a stable positive pressure structure conducive to high temperatures and their long-term maintenance.Analysis of circulation characteristics during extreme high temperature process highlighted the close relationship between regional extreme high temperatures in Xinjiang and the South Asian high-pressure system,particularly with significant positive correlation with the center latitude position.When the main body of the South Asian high pressure in the 100 hPa circulation field is between 55°-90°E and the center area is large,the northward position of the center is conducive to the occurrence of regional extreme high temperature process in Xinjiang.

关 键 词：高温 阶段性变化 南亚高压 伊朗副高 西太平洋副热带高压 

分 类 号：P466[天文地球—大气科学及气象学]