热带太平洋-印度洋海表温度变化及其对西南地区东部夏季旱涝的影响  

ANOMALIES OF SEA SURFACE TEMPERATURE IN PACIFIC-INDIAN OCEAN AND EFFECTS ON DROUGHT/FLOOD IN SUMMER OVER EASTERN OF SOUTHWEST CHINA

作　　者：李永华[1,2] 卢楚翰[2] 徐海明[2] 程炳岩[1] 

机构地区：[1]重庆市气候中心,重庆401147 [2]南京信息工程大学/气象灾害省部共建教育部重点实验室,江苏南京210044

出　　处：《热带气象学报》2012年第2期145-156,共12页Journal of Tropical Meteorology

基　　金：国家自然科学基金项目(40975058);重庆市自然科学基金计划重点项目(CSTC;2008BA0022);重庆市科技攻关项目(CSTC;2009AC0125);重庆市气象局科技计划项目(zl-200810)共同资助

摘　　要：利用1959—2006年西南地区东部20个测站逐日降水量资料和NCEP/NCAR再分析月平均资料,分析了热带太平洋-印度洋海表温度异常特征及其对西南地区东部夏季降水(旱涝)的影响,结果表明:前期赤道东太平洋海表温度偏高,西南地区东部夏季降水偏多的可能性大;当前期春季印度洋海表温度偏高时,西南地区东部夏季降水可能偏多。太平洋区的海表温度距平(SSTA)分布呈"V"字型特征,赤道中东太平洋及南、北美西部沿海的SSTA与赤道西太平洋、南北太平洋的SSTA呈反相关分布,与西太平洋的亚洲大陆东部沿海的SSTA呈正相关,赤道印度洋及南印度洋的大部分地区的SSTA与赤道中、东太平洋的SSTA变化是一致的。当春季赤道中东太平洋及印度洋海表温度(SST)偏高(偏低)时,夏季南亚高压位置偏南(偏北),强度偏强(偏弱),面积偏大(偏小),同时西太平洋副高强度偏强(偏弱),面积偏大(偏小),位置偏南(偏北),西伸(东退)明显,东亚夏季风和南亚夏季风偏弱(偏强),我国华北及华南地区盛行下沉(上升)运动,而整个长江流域及青藏高原东部盛行上升(下沉)运动,西南地区东部也盛行弱的上升(下沉)运动,这有利于西南地区东部降水偏多(偏少),出现洪涝(干旱)的可能性大。Based on the monthly NCEP/NCAR reanalysis and daily precipitation data of 20 stations in the east of Southwest China from 1959 to 2006,the features of sea surface temperature anomaly（SSTA） in the Pacific and Indian Oceans associated with drought/flood in summer over the east of Southwest China have been analyzed.Results show that the rainfall may be more than normal in this region when the SSTA is higher in the equator-eastern Pacific Ocean or Indian Ocean.The distribution features of SSTA show a ‘V’ type in the Pacific;the SSTA in the equatorial middle-eastern Pacific is negatively correlated with coastal regions of the western North America/South America while being positively correlated with coastal regions of the western Pacific Ocean.The tendency of change in the SSTA is consistent between the equatorial or southern Indian Ocean and the equatorial middle-eastern Pacific Ocean.There are close relationships between the summer flood/drought in the east of Southwest China and the SSTA in spring of the equatorial middle-eastern Pacific and Indian Oceans;the rainfall is more than normal when the SSTA is higher.EASM/SASM is weaker when the spring SSTs in the equatorial middle-eastern Pacific and Indian Oceans are higher than normal.

关 键 词：西南地区东部 夏季旱涝 海表温度异常 影响 

分 类 号：P461.2[天文地球—大气科学及气象学]