项目名称： 北半球平流层最后增温事件与南亚夏季风爆发之间联系的机理研究

项目编号： No.41505034

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 天文学、地球科学

项目作者： 胡景高

作者单位： 南京信息工程大学

项目金额： 21万元

中文摘要： 南亚夏季风是亚洲夏季风的重要子系统之一，其爆发早晚及异常对我国天气、气候有着显著的影响。平流层最后增温事件（SFW）是指发生在每年春季，因平流层极区快速增温而导致极涡最后崩溃，极夜急流减弱消失从此转为东风气流的事件，它的发生标志着平流层由冬季环流型向夏季环流型的转变。已有研究表明，20世纪70年代末以来，SFW与南亚夏季风的爆发存在显著的联系，可作为预测南亚夏季风爆发的平流层前期信号，但其中的物理过程和机制仍不清楚。基于平流层–对流层动力和热力耦合变化的观点，本项目拟通过资料诊断和数值模拟研究，详细揭示平流层SFW事件与南亚夏季风爆发之间联系的物理过程和机制，为进一步把握南亚夏季风的爆发及我国短期气候预测提供更多理论基础和方法依据。

中文关键词： 平流层最后增温事件；南亚夏季风；爆发时间；物理机制

英文摘要： The South Asian summer monsoon (SASM) is a key branch of the Asian summer monsoon system, being recognized having remarkable influences on the weather and climate anomalies in China. The stratospheric final warming (SFW) occurs in the springtime and is characterized with a rapid increase in the polar stratospheric temperature resulting in the breakdown of the stratospheric polar vortex, which in turn involves the final transition of the circumpolar zonal wind in the stratosphere from wintertime westerly to summertime easterly. It is revealed by the recent study that the seasonal timing of SFW is significantly related to the onset of the SASM since the end of 1970s and thus acts as an emerging precursor signal in the spring stratosphere for the SASM onset. Until now, however, the physical mechanism for the above relation is not fully understood. Based on the data diagnose and numerical simulation, this project intends to reveal the physical processes and mechanisms in detail for the relation between the seasonal timing of boreal spring SFW and the SASM onset. Investigations on these issues will further help us better understand the SASM onset, but also the linkage of the circulation in spring in the stratosphere-troposphere coupling system. Moreover, it will also help us improve our short-term prediction capabilities in terms of the tropospheric climate by applying the possible stratospheric precursors.

英文关键词： stratospheric final warming;South Asian summer monsoon;onset date;physical mechanism