摘要
基于中国气象局信息中心整编的1960-009年逐日地面最高气温的站点资料及NCEP/NCAR再分析资料,分析了华中地区85个站点的年平均高温日数和高温日平均最高气温的时间、空间变化,同时分析了高温日大气环流特征.结果表明:年平均高温日数和高温日年平均最高气温在时间分布上呈现增暖的趋势,在20世纪60-0年代中期呈降低趋势,之后呈现上升的趋势,尤其在2000年之后,表现得更加明显.年平均高温日数(>35℃)和年平均高温日数(>37℃)在空间分布上均呈现扩大趋势,部分地区年平均高温日数(>35℃)增加10天,但是高温日(>40℃)年平均气温呈弱下降趋势.从大范围高温事件的环流形势来看,7月与8月西太平洋副热带高压脊线北抬至25°～35°N之间.8月586线经向变化,西伸至90°E,100hPa南亚高压发展强大.由此,在对流层中、上层两个高压系统相互配合,并且二者高度场均呈现强大的正距平,这便是形成华中大范围极端高温事件的大气环流形势场.
Based on the daily extreme temperature data from 1960 to 2009 obtained from the Information Center of China Meteorological Administration and on the NCEP/NCAR reanalysis data,an analysis was made of the time and spatial variation of mean extreme maximum temperature （EMT） days and mean maximum temperature （MMT） in 85 stations over central China and of the atmospheric circulation in EMT days.The results shows that annual extreme maximum temperature （EMT） days and mean maximum temperature （MMT） during the EMT days were generally increasing with the passage of time,while they decreased from the 1960＇s to the middle of the 1980＇s.After that there had been an increasing trend,especially since the advent of the 21 th century.Annual extreme maximum temperature EMT days （ 〉35 ℃） and EMT days （ 〉37 ℃） were in the trend of increasing in space.EMT days （〉 35 ℃） in some area increased to 10 days.However,EMT days （ 〉40 ℃） appeared to be decreasing.The atmospheric circulation shows that the 500 hPa subtropical high bate between 25°～ 35°N,586 lines was reinforced to 90°E.100 hPa south Asian high bate was also reinforced and the middle of troposphere coordinated with the top layers when large-scale extreme high temperature events happened.This meant that the high field was of a positive anomaly.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2011年第2期50-55,共6页
Journal of Lanzhou University(Natural Sciences)
基金
国家公益性行业专项项目(GYHY201106034)
国家科技支撑计划项目(2007BAC29B03
2009BAC53B02)
关键词
年平均极端高温日数
高温日平均最高气温
大气环流特征
华中地区
mean extreme maximum temperature day
mean maximum temperature
atmospheric circulation characteristic
central China
