Climatic characteristics of high temperature in East China during 1961-2005

Based on the daily maximum temperature data covering the period 1961-2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days（HTDs）and the mean daily maximum temperature（MDMT）during annual and monthly HTDs in East China were studied.The results show that the mean annual HTDs were 15.1 and the MDMT during annual HTDs was 36.3℃in the past 45 years.Both the mean annual HTDs and the MDMT during annual HTDs were negative anomaly in the1980s and positive anomaly in the other periods of time,oscillating with a cycle of about 12-15 years.The mean annual HTDs were more in the southern part,but less in the northern part of East China.The MDMT during annual HTDs was higher in Zhejiang,Anhui and Jiangxi provinces in the central and western parts of East China.The high temperature process（HTP） was more in the southwestern part,but less in northeastern part of East China.Both the HTDs and the numbers of HTP were at most in July,and the MDMT during monthly HTDs was also the highest in July.In the first 5 years of the 21st century,the mean annual HTDs and the MDMT during annual HTDs increased at most of the stations,both the mean monthly HTDs and the MDMT during monthly HTDs were positive anomalies from April to October,the number of each type of HTP generally was at most and the MDMT in each type of HTP was also the highest.

华东地区夏季高温期的气候特征及其变化规律

基于华东气象站点1961-2005年逐日最高地面气温资料,分析了华东高温日数和高温日平均最高气温的时空动态变化特征。结果表明:过去45年间,华东年均高温日数为15.1天,高温日平均最高气温为36.3oC,高温以12￣15年为显著振荡周期,在20世纪80年代为弱负距平,而在其他时期都为正距平。华东高温日数呈北少南多的空间分布,高温日平均最高气温以安徽、浙江和江西较高,高温过程数是东北部少,西南部多。高温日数和高温过程数是以7月最多,高温日平均最高气温也是以7月最高。在21世纪最初5年,站点高温日数和高温日平均最高气温增加,4-10月高温都为正距平,各级高温过程数总体最多,各级高温过程日平均最高气温也最高。