赤道西太平洋冷模影响东亚冬季气候异常的机理研究

赤道西太平洋冷模（Western Tropical Pacific Cold Mode, 以下简称WTPCM）是通过对赤道太平洋冬季海温距平场和北半球500毫巴高度场做奇异向量分解得到的第二模态。前期的研究结果表明，WTPCM对我国冬季气候异常的影响非常显著。和我国冬季气候变化之间有着非常密切的联系。当WTPCM处于正位相时，我国大部分地区的气温异常偏暖,反之亦然。本项目拟通过对中国站点观测资料,NCEP再分析资料和多个全球海-气耦合模式的季节预报输出结果进行资料诊断和动力分析，利用数值模式设计数值试验的方法对WTPCM和东亚冬季气候之间的关系做进一步的深入分析，研究WTPCM影响东亚冬季气候异常的内在机理以及目前全球海-气耦合模式对WTPCM的预报能力。此项目的研究结果不仅有助于深入了解东亚冬季气候异常的成因和机理，而且能为提高东亚冬季气候预测提供潜在的预报因子，为防灾减灾提供决策服务。

The western tropical Pacific cold mode (hereafter, WTPCM) is the second pair of mode of the Singular Value Decomposition (SVD)analysis between the tropical Pacific sea surface temperature (SST) and the 500-hPa geopotential height in the Northern Hemisphere in wintertime. Previous studies showed that WTPCM can significantly influence the surface air temperature (SAT) in China. When the WTPCM is in its positive (negative) phase the SAT in China is warmer-than-normal (colder-than-normal). This project aims to further investigate the mechanisms of the influence of the WTPCM to the climate variability of the East Asian winter climate by analyzing the observations and the output from air-sea coupled numerical models. Atmospheric numerical models will be used to do numerical experiment to explore the mechanisms behind the relationship between the WTPCM and the East Asian winter climate. To understand the capability of the air-sea coupled numerical models in predicting the bahavior of the WTPCM. The results of the project will contribute to a better understanding of the mechanism of the climate change of the East Asian winter climate. It can also help to improve the seasonal prediction of the East Asian winter climate and provide support for the natural disasters reduction and prevention.