西南地区冬季气温和降水的时空变化(英文)

编号 zgly0001585435

文献类型 期刊论文

文献题名 西南地区冬季气温和降水的时空变化(英文)

作者 蒋兴文  李跃清 

作者单位 CollegeofAtmosphericSciences  LanzhouUniversity  InstituteofPlateauMeteorology  ChinaMeteorologicalAdministration 

母体文献 Journal of Geographical Sciences 

年卷期 2011年02期

年份 2011 

分类号 P467 

关键词 SouthwestChina  winter2010  drought  wintermonsoon  northernhemisphereannularmode(NAM  AO) 

文摘内容 In recent years,the socio-economic impacts of winter extreme climate events have underscored the importance of winter climate anomalies in Southwest China (SWC).The spatio-temporal variability of surface air temperature (SAT) and precipitation in SWC and their possible causes have been investigated in this paper based on observational data from 1961 to 2010.The results indicate that SAT anomalies in SWC have two dominate modes,one is homogenous,and the other a zonal dipole.The former is caused by the anomalies of East Asian winter monsoon;the latter arises from the anomalies of both subtropical west Pacific high and regional cold air in lower troposphere.The most dominant mode of precipitation anomalies in SWC is homogenous and it has a high correlation with northern hemisphere annular mode (NAM,AO).Neither NAM nor ENSO has significant impacts on SAT in SWC.The anomalies of NAM are associated with the anomalies of tropical circulations,and there-fore precipitation over the SWC.When NAM is in positive (negative) phase,the winter pre-cipitation is more (less) than normal in SWC.Winter precipitation increase over the whole SWC is associated with the El Nino.However,during La Nina winter,the pattern is not uni-form.There is an increase in precipitation over the central parts and a decrease in western and eastern parts of SWC.The severe drought in SWC in winter 2010 is more likely caused by anomalies of NAM,not El Nino.