Full-Text Search:
Home|Journal Papers|About CNKI|User Service|FAQ|Contact Us|中文
《科学通报(英文版)》 2009-24
Add to Favorite Get Latest Update

The responses of East Asian Summer monsoon to the North Atlantic Meridional Overturning Circulation in an enhanced freshwater input simulation

YU Lei1, GAO YongQi1,2, WANG HuiJun1, GUO Dong1,3 & LI ShuangLin1 1 Nansen-Zhu International Research Center, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; 2 Nansen Environmental and Remote Sensing Center/Bjerknes Centre for Climate Research, Bergen, N-5006, Norway; 3 Sate Key Laboratory of Earth Surface Processes and Resource Ecology, Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China  
We investigated the response of the East Asian Summer Monsoon (EASM) to a weakened Atlantic Meridional Overturning Circulation (AMOC) and its mechanism in an enhanced freshwater input experiment (FW) by using a fully-coupled climate model. The response was a weakened EASM and the mechanisms can be explained as follows. The simulated weakened AMOC resulted in a drop in sea surface temperature (SST) in the North Atlantic (NA) and, correspondingly, an anomalous high sea level pressure (SLP) over the North American regions, which in turn increased the northeast surface winds across the equator in the eastern tropical Pacific (ETP). The anomalous northeast winds then induced further upwelling in the ETP and stronger air/sea heat exchange, therefore leading to an anomalous cooling of the eastern tropical sea surface. As a result, the climatologic Hadley Circulation (HC) was weakened due to an anomalous stronger sinking of air in the ETP north of the equator, whereas the Walker Circulation (WC) in the western tropical Pacific (WTP) north of the equator was strengthened with an eastward-shifted upwelling branch. This feature was in agreement with the anomalous convergent winds in the WTP, and led to a weakened EASM and less East Asian summer precipitation (EASP). Furthermore, comparison with previous freshwater experiments indicates that the strength of EASP could be influenced by the magnitude of the added freshwater.
【Fund】: Supported by the National Natural Science Foundation of China (Grant Nos. 40805031 and 40875047);; National Basic Research Program of China (Grant No. 2009CB421401);; Hundred Talent Program of the Chinese Academy of Sciences (Grant No. 8-059405);; Knowledge Innovation Key Program of the Chinese Academy of Sciences (Grant No. KZCX2-YW-BR-14)
【CateGory Index】: P425.42
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©2006 Tsinghua Tongfang Knowledge Network Technology Co., Ltd.(Beijing)(TTKN) All rights reserved