1980—2019年江淮地区夏季气温变化及其异常年环流特征
Summer Temperature Changes from 1980 to 2019 in Jianghuai Region and Circulation Characteristics in Anomalous Years
中文摘要：
利用1980—2019年ERA5月平均2 m气温资料、NCEP/NCAR提供的大气环流资料以及NOAA的海表温度资料，分析了江淮地区夏季气温变化及其异常年环流特征。结果表明：江淮地区夏季气温整体呈波动上升趋势，冷暖交替出现，在2000年发生突变，空间分布上表现出整体一致性；气温变化主要受西太平洋副热带高压（简称西太副高）、东亚夏季风及西伯利亚冷空气的影响；高温年江淮地区为大范围的位势高度正距平控制，西太副高整体偏西偏强，江淮地区处于副高脊线附近，高纬度阻塞高压较强，低温年则反之；高温年赤道中东太平洋及西太平洋海温分布具有拉尼娜事件的特征，而低温年赤道中东太平洋及西太平洋海温分布具有厄尔尼诺事件的特征；赤道中东太平洋海温异常偏高年江淮地区气温整体偏低，偏低年反之。
中文关键词：
江淮地区，夏季气温变化，夏季极端气温，大气环流特征
KeyWords：
Jianghuai Region, summer temperature changes, extreme summer temperature, atmospheric circulation characteristics
Abstract：
Based on ERA5 monthly average temperature of 2 m, NCEP/NCAR reanalysis data and NOAA SST data from 1980 to 2019, the summer temperature changes and circulation characteristics of anomalous years in Jianghuai Region were analyzed. The results show that the summer air temperature in Jianghuai Region exhibits a rising trend, with the fluctuation of cold and warm temperatures appearing alternately and the abrupt changes occuring in 2000, showing the overall consistency in spatial distribution. The temperature variation is mainly influenced by the West Pacific subtropical high (WPSH), East Asian summer monsoon and cold air over Siberia. In the high temperature years, Jianghuai Region is controlled by a large range of positive geopotential height anomaly, and the WPSH is generally more westward and stronger. Jianghuai Region is near the ridge line of the WPSH, with strong blocking high at high latitude. Opposite situations occur in low-emperature years. In high temperature years, the SST distribution in equatorial middle-eastern Pacific and western Pacific is characterized by La Ni?a events, while in low temperature years, the SST distribution in the same region is characterized by El Ni?o events. The anomalous high SST years in equatorial Middle-Eastern Pacific are accompanied by the overall low temperature in Jianghuai Region and vice versa.