南通地区夏季高温特征和极端高温事件分析

Characteristics of Summer High Temperature and Comparison of Extreme Heat Events in Nantong Area

利用1961—2019年南通各区县气象站的高温日数、极端最高气温资料,探究了南通地区高温特征和极端高温事件。结果表明,南通地区高温日数呈现西多东少的分布特征,海安站的总高温日数和年平均高温日数多于启东站。进入21世纪,南通本站高温日数明显增加,增幅为2.9d/10a。2013、2017年高温预警发布频繁,南通地区出现的高温具有极端性,表现为高温日数较多,多站最高气温突破历史极值。2013年7—8月份,南通本站高温有3个阶段,累计高温日数多。2017年高温主要集中在7月中下旬,高温持续18d。西太平洋副热带高压偏强偏西、稳定控制本地,是极端高温事件出现的直接原因。

Based on the data of the number of high temperature days and extreme maximum temperature at the meteorological stations in districts and counties of Nantong from 1961 to 2019,this paper explores the local high temperature characteristics and extreme high temperature events.The number of high temperature days in Nantong area is more in the west than in the east.The total number of high temperature days and the annual average number of high temperature days in Hai’an station are higher than that in Qidong station.In the 21 st century,the number of hot days in Nantong has increased significantly,with an increase of 2.9 d/10 a.The high temperature in Nantong in 2013 and 2017 was extreme,which was manifested in the number of high temperature days and the highest temperature in many stations breaking through the historical extreme value.From July to August in 2013,there were three stages of high temperature in Nantong station.The number of accumulated high temperature days was more,and the high temperature warning was issued frequently.In 2017,the high temperature was mainly concentrated in mid-to-late July and lasted for 18 days.The western Pacific subtropical high is strong and extends westward,which is the direct cause of the extreme heat events.