Seasonal response of Asian monsoonal climate to the Atlantic Multidecadal Oscillation
Seasonal response of Asian monsoonal climate to the Atlantic Multidecadal Oscillation
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亚洲季风气候对大西洋数十年涛动的季节响应
DOI：
10.1029/2008jd010929
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发表时间：
2009-01-29
影响因子：
4.4
通讯作者：
Luo, Dehai
中科院分区：
文献类型：
--
作者：
Wang, Yanming;Li, Shuanglin;Luo, Dehai
[1]通过综合观测分析和大气环流模式的集合试验，研究了大西洋年代际振荡（AMO）对亚洲季风气候的影响。三个AGCM强迫指定的气候季节循环的海表温度（SST）或与额外的SST异常代表的AMO温暖的阶段。观测和模型的结果一致表明，温暖的AMO阶段引起东亚和印度北方气温升高，但在印度中南部大部分地区的气温在所有四个季节下降。这种正AMO异常也导致印度中部和南部每个季节的降雨量增加，特别是在夏季和秋季。相反，AMO对东亚降水的影响是季节性的：在中国东南部，它导致夏季降水增加，但在秋季降水减少。这些AMO影响是通过使欧亚地区对流层中上层四季变暖来实现的，导致亚洲冬季风减弱，夏季风增强。此外，对流层加热异常的形成可能与亚洲高空急流的导波机制有关。
[1] The influence of the Atlantic Multidecadal Oscillation (AMO) on Asian monsoonal climate in all four seasons is investigated by comprehensive observational analyses and ensemble experiments with atmospheric general circulation models (AGCMs). Three AGCMs are forced by prescribed climatological seasonal cycle of sea surface temperature (SST) or with additional SST anomalies representing the warmth phase of the AMO. The results in both the observations and the models consistently suggest that the warm AMO phase gives rise to elevated air temperatures in East Asia and northern India but decreased air temperatures in much of central-southern India in all four seasons. This positive AMO anomaly also causes more rainfall in central and southern India in every season, particularly in summer and fall. In contrast, the sign of AMO influences on East Asian rainfall is season-dependent: in southeastern China, it induces increased rainfall in summer but suppressed rainfall in autumn. It is suggested that these AMO influences are realized by warming Eurasian middle and upper troposphere in all four seasons, resulting in weakened Asian winter monsoons but enhanced summer monsoons. Furthermore, the formation of the troposphere heating anomaly may be related to the wave guidance mechanism associated with the Asian upper jet.