南亚高压强度年代际变化及其与热带副热带海温关系  

THE INTERDECADAL VARIATION OF SOUTH ASIAN HIGH AND ITS ASSOCIATION WITH THE SST OF TROPICAL AND SUBTROPICAL REGIONS

作　　者：彭丽霞[1,2] 朱伟军[1,2] 李忠贤[1,2] 倪东鸿[1,2] 陈海山[1,2] 潘林林 

机构地区：[1]南京信息工程大学气象灾害预警与评估协同创新中心,江苏南京210044 [2]南京信息工程大学气象灾害教育部重点实验室,江苏南京210044 [3]美国大气研究中心,科罗拉多博尔德市80301

出　　处：《热带气象学报》2016年第2期145-154,共10页Journal of Tropical Meteorology

基　　金：国家自然科学基金(41105059;61103142;41230422);科技部公益性行业(气象)科研专项(GYHY201306028;GYHY201206017);江苏省高校自然科学研究项目资助(11KJB170006);江苏省自然科学基金-杰出青年基金项目(BK20130047);"新世纪优秀人才支持计划"共同资助

摘　　要：采用1948—2012年NCEE/NCAR月平均再分析资料和CAM3.0大气环流模式,探讨了南亚高压(SAH)强度年代际变化及其与热带、副热带海温的关系。(1)SAH呈显著年代际变化,以1970年代末期为界,之前强度偏弱;之后强度增强、面积扩大、东西扩展,冬季西侧扩展程度大于东侧,夏季则相反。(2)与SAH强度年代际变化相对应,1970年代末期以后,热带、副热带辐散风分量表现为显著的两个上升区和三个下沉区。两个上升区一个位于东太平洋,另一个随季节变化位置有所改变,冬季位于印度洋,夏季位于南海-西太平洋海域;三个主要下沉区分别位于非洲中北部、亚洲东部和中太平洋地区。(3)与SAH强度年代际变化相对应,夏季低层涡旋风分量在南海-西太平洋地区表现为异常气旋性环流,冬季低层涡旋风分量在印度洋表现为异常气旋性环流,而在赤道中太平洋则呈现异常反气旋性环流。(4)数值试验表明:SAH年代际变化与热带、副热带海温关系密切,冬季印度洋海温起作用较大,夏季则是南海-西太平洋海温起作用较大,另外东太平洋海温也起了一定作用。By using the NCEP/NCAR monthly reanalysis data from 1948 to 2012, The interdecadal variation of South Asian High （SAH） and its relationship with 5ST（ Sea surface temperature） of the tropical and subtropical regions is studied by the NCAR CAM 3.0 general circulation model, it is found that ： 1 ） the intensity of SAH represents a remarkable interdecadal variation characteristic, the intensity of SAH experienced from weak to strong at the late 1970s, and after the late 1970s , its strength is enhanced and the area is expanded in the east-west direction. The expansion degree to west direction in winter is greater than to east direction, while it is opposite in summer. 2） Corresponding to the interdeeadal variation of SAH intensity, after the late 1970s, the divergent component of wind field has two ascending and three descending areas. Of the two ascending areas, one is located in the East Pacific Ocean, the other location varies with the season from the Indian Ocean in winter to the South China Sea-West Pacific Ocean in summer. Three descending areas are located in the north-central Africa, the east Asia and the Middle Pacific region respectively. 3 ） Corresponding to the interdecadal variation of SAH intensity, the rotational component of wind field at the lover level is an anomalous cyclone over the South China Sea-West Pacific Ocean in summer, while in winter, it is an anomalous cyclone over the Indian Ocean, still an anomalous anticyclone over the equatorial middle pacific. 4） Numerical simulations show that the interdeeadal variation of SAH is closely related to the SST of the tropical and subtropical regions. The SST of Indian Ocean plays the important role in winter, while in summer, the SST of the South China Sea-West Pacific Ocean plays the important role, in addition, the SST of the East Pacific has also played a certain role.

关 键 词：南亚高压 年代际 辐散风 涡旋风 海温 

分 类 号：P434[天文地球—大气科学及气象学]