热带风场季内振荡强度与海表温度异常关系研究  

Relationships between Tropical Wind Intraseasonal Oscillation Intensity and Sea Surface Temperature

作　　者：李丽平[1,2] 王盘兴[1,2] 徐学义[3] 林中庆[1,2] 

机构地区：[1]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 [2]南京信息工程大学大气科学学院,江苏南京210044 [3]泰安市气象局,山东泰安271000

出　　处：《大气科学学报》2009年第3期424-435,共12页Transactions of Atmospheric Sciences

基　　金：国家科技支撑计划项目(2007BAC29B02);教育部留学归国人员基金项目(80185);国家自然科学基金资助项目(40675025)

摘　　要：利用NCEP/NCAR逐日风场及英国气象局逐月海表温度资料,研究了对流层高低层风场季内振荡强度季节变化特征,探讨了其年际及年代际异常特征与海表温度异常的关系。热带印度洋、热带西太平洋是高低层风场季内振荡终年均活跃的区域。对流层高低层风场季内振荡强度异常与海表温度异常均不存在确定的局地关系。风场季内振荡能量异常与海表温度异常在年代际尺度上具有良好对应关系,20世纪70年代中后期以来,赤道东太平洋海温异常升高,Walker环流减弱,导致亚洲区域季风季内振荡强度减弱,赤道太平洋区域200hPa(850hPa)风场季内振荡在赤道东太平洋增强(减弱),在印度洋东南部—印尼—中西太平洋的暖池区域减弱(增强),促进了ElNino事件的增强。对流层高低层风场季内振荡强度年际异常与ElNino事件关系密切,这一特征在低层(850hPa)风场表现更显著。在事件发展初期,热带中西太平洋区域850hPa风场季内振荡异常增强并东移,事件发生之后这些区域能量减弱。大气季内振荡可能是ElNino事件的激发因素。By using the NCEP/NCAR daily wind data and the monthly sea surface temperature（SST） data of the U. K. weather bureau, the seasonal characteristics of upper and low troposheric wind intraseasonal oscillation （ISO） intensity are studied to reveal the realationship of its interannual and interdecadal anomalies with sea surface temperature anomalies. It is found that the ISO is the most active over the tropical Indian Ocean and tropical western Pacific for 200 hPa and 850 hPa zonal wind fields. The relationship of the ISO intensity anomaly of tropical 200 hPa and 850 hPa zonal winds with sea surface temperature anomaly are investigated individually, there are no notable local correlation relationships between 200 hPa/850 hPa wind and sea surface temperature, whereas, there are clear relationships on the interdecadal scale. Since the middle and late 1970s, the weakening of the Walker circulation and the rise in SST in the equatorial eastern Pacific have resulted in the weakening of ISO in the Asian monsoon region;the strengthening（weakening） of 200 hPa（850 hPa） wind ISO in the equatorial eastern Pacific and the weakening （strengthening） of the wind ISO in the equatorial southeast Indian Oceanwestern and central Pacific region have augmented the strengthening of E1 Nino events. The interannual variations of wind intraseasonal oscillation intensity is closely related to ENSO events, especially at 850 hPa level. The ISO will strengthen and move eastward during the early stage of E1 Nino development in the tropical middle and western Pacific, and weaken subsequently when the event takes place. The at-mospheric ISO may be a factor which excitates E1 Nino events

关 键 词：季节内振荡强度 风场 海表温度 年际年代际变化 

分 类 号：P732[天文地球—海洋科学]