摘要
基于NCEP/NCAR再分析资料及全国160个测站降水资料,分析了2～3月青藏高原地表温度升温幅度与6月长江中下游地区降水的关系。结果表明:青藏高原2～3月地表温度升温幅度的主空间分布型为边缘升温大、中心升温小,低海拔大、高海拔小。这种升温形势与长江中下游南部降水呈明显的负相关关系:在升温幅度大的年份,长江中下游南部降水较常年偏少;而升温幅度小的年份,长江中下游南部降水明显增加。进一步分析表明,升温弱年大气环流的形势和各种天气系统的配置为长江中下游南部降水提供了更有利的水汽、动力及热力条件,其中100 hPa南亚高压强度整体偏强并向东西方向伸展,500 hPa极涡增强偏东、贝加尔湖及鄂霍次克海之间大脊增强及西太平洋副热带高压西伸是降水增加的主要原因。
Based on NCEP/NCAR reanalysis data and precipitation data of 160 stations in China,the correlation between variations of surface temperature in the Tibetan Plateau（TP） from February to March and precipitation in the mid-and lower-reaches of Yangtze River in June has been studied.The results show that the main spatial distribution of the increamen of surface temperature in TP from February to March is higher in its edge and lower in its center,but highter in low sea level elevation and vice versa.There is obvious negative correlation between the increamen of surface temperature and precipitation in the southern part of the mid-and lower-reaches of Yangtze River.When the increasmen of surface temperature is high,precipitation in the southern part of mid-and lower-reaches of Yangtze River reduces,and vice versa.Further research indicates,when the increasmen of surface temperature is low,the atmospheric circulation and synoptic system provide favorable vapor,dynamic and thermodynamic conditions for precipitation in the southern part of mid-and lower-reaches of Yangtze River.The south Asia high on 100 hPa becomes strong and spreads meridianal,the polar vortex on 500 hPa turns strong and eastward,the ridge between the Baikal and the Okhotsk strengthens and the west Pacific subtropical high spreads westward,which must be the most important reasons of the precipitation increasing.
出处
《高原气象》
CSCD
北大核心
2010年第3期579-586,共8页
Plateau Meteorology
基金
2009年度武汉区域气象中心科技发展基金重点项目(QY-Z-200902)资助
关键词
青藏高原
地表温度
长江中下游
降水
Tibetan Plateau
Surface temperature
The mid-and lower-reaches of Yangtze River
Precipitation
