2021年6—9月广西异常高温成因分析

Cause analysis of abnormal high temperature in Guangxi from June to September 2021

2021年6—9月广西经历了1951年以来最高的月平均气温,大范围高温天气频发。利用1961—2021年广西国家地面气象观测站日平均气温和日最高气温观测资料、1991—2021年ERA5再分析资料和西太平洋副热带高压指数资料,对此次广西异常高温的特征和成因进行了研究分析。结果表明,气候变暖是导致此次高温事件的重要气候背景,西太平洋副热带高压异常偏强位置偏西偏北、中纬度西风带扰动影响偏北以及热带气旋影响偏弱是造成广西气温异常偏高的主要原因。

From June to September 2021, Guangxi experienced the highest monthly average temperature since 1951, with frequent high-temperature weather in a wide range. Based on the observation data of daily average temperature and daily maximum temperature of Guangxi national ground meteorological observatory from1961 to 2021, ERA5 reanalysis data from 1991 to 2021, and Western Pacific subtropical high index data, the characteristics and causes of the abnormal high temperature in Guangxi were studied. The results show that climate warming is an important climate background leading to the high temperature event. The main reasons for the abnormally high temperature in Guangxi are the abnormally strong subtropical high in the Western Pacific,the northwest of the position, the north of the disturbance of the middle latitude westerlies and the weak influence of tropical cyclones.