热带对流活动对川渝地区夏季降水的影响  

Impact of Tropical Convective Activity on Summer Precipitation in Sichuan and Chongqing Regions

作　　者：董一平[1] 陈权亮[2] 

机构地区：[1]成都信息工程学院,四川成都610225 [2]成都信息工程学院高原大气与环境四川省重点实验室大气科学学院,四川成都610225

出　　处：《安徽农业科学》2010年第12期6329-6332,6440,共5页Journal of Anhui Agricultural Sciences

基　　金：四川省教育厅科研项目(08zc042);成都信息工程学院科研启动项目

摘　　要：利用1974～2008年川渝地区22站月平均降水资料、NCEP/NCAR月平均再分析资料、OLR资料,通过SVD方法,分析研究了川渝地区夏季降水与春季、夏季热带OLR场的关系,并通过相关分析方法、合成分析方法从高度场、风场等方面分析了热带对流活动对川渝地区夏季降水的影响。结果表明,热带对流活动与川渝地区夏季降水之间呈显著的正相关,即夏季热带对流活动强(弱),川渝地区夏季降水偏多(少);当春季经纬度75°～110°E、25°～10°S区域的OLR偏低(偏高),表明这一地区对流活动强(弱),夏季川渝地区降水将偏多(偏少),南印度洋春季热带对流活动的强弱对川渝地区夏季降水有一定的指示意义。若夏季经纬度85°～120°E、15°～5°N区域OLR偏低(高),这一地区对流活动强(弱),夏季川渝地区降水将偏多(少)。热带对流活动异常引起东亚地区大气环流异常,强(弱)热带对流活动年,副热带高压位置偏西(东),南亚高压位置偏东(西),自南海进入中国的水汽输送偏强(弱),经向环流偏强(弱),有更多的暖湿空气自热带地区输入到川渝地区,川渝地区夏季降水偏多(少)。Based on monthly mean precipitation data of 22 stations in Sichuan and Chongqing regions,NCEP/NCAR monthly mean re-analysis data and OLR data,the relationship between tropical OLR and the summer precipitation in Sichuan-Chongqing region was studied by means of SVD analysis.Then the impact of OLR on summer precipitation in Sichuan-Chongqing region was interviewed.The results showed that there was evidently positive correlation between tropical convection and the summer precipitation in Sichuan and Chongqing regions.While the OLR was lower,implying that tropical convection was stronger（weaker）,summer precipitation in Sichuan-Chongqing region was more（less）.And if there was lower（higher）OLR in spring in the region 75°-110° E,25°-10° S,or lower（higher）OLR in summer in the region 85°-120° E,15°-5° N,the summer precipitation in the Sichuan and Chongqing region would be more（less）.The summer OLR in South Indian Ocean had indicative signal to the summer precipitation in the Sichuan and Chongqing regions.Tropical convective anomaly can cause the circulation anomaly in East Asian.In those years,while tropical convective activity was strong（weak）,the location of subtropical high（SH）was westward（eastward）,the location of South Asian High（SAH）was eastward（westward）and the vertical circulation would be stronger（weaker）.These changes resulted in more（less）summer precipitation in Sichuan-Chongqing region.

关 键 词：热带对流 夏季降水 川渝地区 

分 类 号：P461[天文地球—大气科学及气象学]