欧亚阻高-东北冷涡“气候效应”机理与动力-统计预测研究

The mid-latitude blocking anticyclones over Eurasia (MLBAE) and northeast cold vortex (NCV) are both independent and interactive atmospheric circulation systems. Although these two systems have significant influence on weather and climate, especially in short-term climate, their indication functions to short-term climate prediction have been unclear. For the reason that they are synoptic scale systems which do not match with the short-term climate processes, which makes it difficult to consider these two factors in short-term climate prediction. This program aims to propose the conception of the "Climate Effect" of MLBAE-NCV based on the consideration of the cumulative effects of repeated synoptic scale system anomalies, and investigate the influencing mechanisms of MLBAE and NCV, and analyze the influence of the different configurations of the climate and abnormal states of MLBAE and NCV on the "Climate Effects" as well as the comprehensive "Climate Effect" of these two systems. Moreover, the program also attempts to reveal the corresponding relationship between the strength of "Climate Effect" and summer climate anomaly, and explains the dynamic mechanisms of this relationship combined with the dynamic processes of atmospheric circulation systems. Finally, by using the historical data and dynamic-statistic prediction theory, we wish to develop the prediction schemes of MLBAE and NCV combined with dynamic-statistic theory, and apply these related research findings to the prediction of the flood/drought distribution in China, especially the prediction of the rain belt. This research project intends to improve the short-term climate predictive skills, and strives to make new progress in the prediction of the mid-latitude atmospheric circulation over Eurasia and the summer climate in China.

欧亚中高纬阻塞高压和东北冷涡是独立且有相互作用的环流系统，但二者在短期气候预测中的应用一直是一个难点。究其原因两者均为天气尺度系统，在尺度上与短期气候过程不相匹配，因而很难在气候预测中加以考虑。本项目旨在考虑多次天气尺度异常活动的累积影响，提出欧亚阻高-东北冷涡的"气候效应"概念，着重从气候学的角度研究欧亚阻高和东北冷涡作用机制，分析两者气候态、异常态的不同配置对其"气候效应"强弱的影响，以及两者所形成的综合"气候效应"；揭示这种"气候效应"与夏季气候异常的对应关系，以及结合环流系统的动力发展过程解释这种关系的动力学机理；利用历史资料和动力-统计预测原理，有针对性的研发基于欧亚阻高-东北冷涡的动力-统计相结合的预测方案，实现将阻高和冷涡的"气候效应"应用于我国夏季旱涝尤其是主雨带位置的预测中。项目旨在提高短期气候预测技巧，力争在欧亚中高纬环流和我国夏季气候预测等方面取得新进展。

针对欧亚中高纬阻塞高压和东北冷涡既相互独立又有相互联系的天气尺度环流系统，紧紧围绕如何延长二者预报时效，使之与低纬的东亚季风环流系统预报时效相匹配的难点和热点问题，自2014年以来项目组成员按照计划书开展了四个方面研究工作，取得了如下创新成果：1）提出了欧亚阻塞高压“气候效应”的概念及其有别传统的识别方法，开展了欧亚中高纬阻塞高压关键区高度场距平跨季度预测方法研究；2）定义了表征东北冷涡空间分布特征的“广义冷涡”过程和强度指数，开展了东北冷涡“气候效应”的研究；3）提出了暴雨“积成效应”、台风降水的“气候效应”新概念，定义了“积成效应”指数，追踪了暴雨“积成效应”期间的水汽来源；4）开展北半球冬季大气活动中心气候特征分析研究，研究西太副高两次北跳时间的年代际特征及与PDO的调制，揭示了增暧背景下冬季亚洲北部偏冷与次夏长江中下游高温潜在的联系，研究东北亚初夏、盛夏和传统夏季降水特征及环流型异同性等与气候效应相关的研究工作。研究成果应用于实时的短期气候预测中，取得了很好的预测效果；在项目的实施过程中，发表学术论文28篇，其中SCI论文17篇，国外期刊16篇，出版专著1部。