北极涛动对ENSO影响的研究进展
Progress in the Study of the Influence of Arctic Oscillation on ENSO
中文摘要：
北极涛动（AO）是北半球中高纬地区大气环流年际变率的第一主导模态，厄尔尼诺-南方涛动（ENSO）则是热带太平洋地区年际变化的最强信号。这两个气候系统对全球大范围的天气和气候都能产生显著的影响。总结了近年来关于AO影响ENSO的最新研究进展，试图促进对中高纬度大气系统影响热带系统物理过程的理解。研究表明，春季AO对随后冬季ENSO的爆发存在显著的影响，其中北太平洋中纬度地区的天气尺度波与平均流之间的相互作用及其相关的涡度输送对赤道西太平洋异常西风的形成起着重要的作用。在年代际时间尺度上，研究发现，春季AO对随后冬季ENSO的影响在20世纪70年代初发生了一次显著的年代际变化，该年代际变化与北太平洋地区风暴轴强度的年代际变化紧密相联。研究还揭示了春季AO对ENSO影响的不对称性，即只有当春季AO处于正位相时，才能对随后冬季赤道中东太平洋海温产生显著影响。研究发现春季AO位相变化对前冬NPO与后一个冬季ENSO之间的关系具有显著的调制作用。此外，研究还发现，除春季AO外，11月AO对随后春季和夏季赤道中东太平洋海温也存在显著的影响，这主要和北太平洋地区风暴轴气候态强度的年循环有关。
中文关键词：
北极涛动，厄尔尼诺-南方涛动，波流相互作用，风暴轴
KeyWords：
AO, ENSO, wave-mean flow interaction, storm track
Abstract：
Arctic Oscillation (AO) is the dominant mode in the atmospheric circulation variability over the extra-tropical Northern Hemisphere. El Ni?o-Southern Oscillation (ENSO) is the primary mode in air-sea interaction over the tropical Pacific on interannual timescale. Variations of AO and ENSO exert substantial influences on the weather and climate anomalies over large areas in the globe. This paper reviews the studies of the influence of AO on ENSO, to improve our understanding the physical processes in the influence of extratropical atmospheric circulation on the tropical climate. It was found that the AO in spring has a significant influence on the ENSO events in subsequent winter. Interaction between synoptic scale eddy and low frequency mean flow over North Pacific plays a key role in the formation of the spring AO-related westerly wind anomalies over tropical western Pacific. The connection between the spring AO and subsequent winter ENSO experiences a significant interdecadal change around the early 1970s. This interdecadal change is closely related to the interdecadal change in the storm track intensity over North Pacific. The influence of the spring AO on the subsequent winter is asymmetric. Spring AO can exert significant influences on the following winter ENSO events only in its positive phase. Spring AO has a significant modulation effect on the linkage between previous winter North Pacific Oscillation and the following winter ENSO. In addition, the AO in November can exert significant influences on the sea surface temperature anomalies over tropical central-eastern Pacific in the following spring and summer. The intensification of the North Pacific storm track activity plays an important role in determining whether the variability of AO can exert influences on the subsequent SST anomalies in the tropical central-eastern Pacific.