Responses of East Asian summer monsoon to historical SST and atmospheric forcing during 1950-2000
Responses of East Asian summer monsoon to historical SST and atmospheric forcing during 1950-2000
复制标题
1950-2000年东亚夏季风对历史海温和大气强迫的响应
DOI：
10.1007/s00382-008-0482-7
复制
发表时间：
2010-03-01
期刊：
影响因子：
4.6
通讯作者：
Lu, Jian
中科院分区：
文献类型：
--
作者：
Li, Hongmei;Dai, Aiguo;Lu, Jian
东亚夏季风环流和中国东部夏季降水在20世纪下半叶经历了较大的年代际变化。为了研究这些变化背后的潜在原因，分析了使用国家大气研究中心(Ncar)社区大气模型版本3(Cam3)和地球物理流体动力学实验室(Gfdl)大气模型版本2.1(am2.1)进行的一系列模拟。这些模拟是分别在不同的历史强迫下进行的，即热带海洋表面温度(SSTs)、全球SSTs、温室气体加气溶胶以及全球SSTs和温室气体加气溶胶的组合。这项研究着重于这些个别强迫在1950-2000年期间引起东亚地区季风和降水变化的相对作用。两个模式的模拟结果表明，主要来自热带地区的SST强迫能够引起大部分观测到的东亚夏季风环流减弱，而温室气体加上(直接)气溶胶强迫增加了海陆热对比，从而增强了东亚夏季风环流。结果表明，近几年热带气候变暖，特别是与以太平洋中东部为中心的热带年代际变率有关的气候变暖，是20世纪70年代末以来东亚夏季风减弱的主要原因。然而，对中国东部相对较小尺度的降水变化模式的真实模拟仍然是全球模式面临的挑战。
The East Asian summer monsoon (EASM) circulation and summer rainfall over East China have experienced large decadal changes during the latter half of the 20th century. To investigate the potential causes behind these changes, a series of simulations using the national center for atmospheric research (NCAR) community atmospheric model version 3 (CAM3) and the geophysical fluid dynamics laboratory (GFDL) atmospheric model version 2.1 (AM2.1) are analyzed. These simulations are forced separately with different historical forcing, namely tropical sea surface temperature (SSTs), global SSTs, greenhouse gases plus aerosols, and a combination of global SSTs and greenhouse gases plus aerosols. This study focuses on the relative roles of these individual forcings in causing the observed monsoon and rainfall changes over East Asia during 1950-2000. The simulations from both models show that the SST forcing, primarily from the Tropics, is able to induce most of the observed weakening of the EASM circulation, while the greenhouse gas plus (direct) aerosol forcing increases the land-sea thermal contrast and thus enhances the EASM circulation. The results suggest that the recent warming in the Tropics, especially the warming associated with the tropical interdecadal variability centered over the central and eastern Pacific, is a primary cause for the weakening of the EASM since the late 1970s. However, a realistic simulation of the relatively small-scale rainfall change pattern over East China remains a challenge for the global models.