江淮流域夏季极端降水过程中天气尺度扰动结构特征及形成机制的研究

项目名称： 江淮流域夏季极端降水过程中天气尺度扰动结构特征及形成机制的研究

项目编号： No.41475043

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 刘鸿波

作者单位： 中国科学院大气物理研究所

项目金额： 84万元

中文摘要： 江淮流域夏季的极端降水预报一直是国内外气象界关注的热点问题。个例分析表明，中纬度大气环流中时间周期为3-8天的天气尺度扰动是造成江淮流域夏季极端降水过程的关键系统。然而，它们在江淮流域强降水事件的已有研究中往往被作为高频噪声滤掉了。因此，本项目拟以已有个例研究为基础，利用29年的降水和环流资料，在国际上首次从气候统计的角度，研究江淮流域夏季极端降水过程中天气尺度扰动演变特征和三维空间结构，天气尺度扰动对江淮流域夏季极端降水事件形成和发展的作用，以及东亚大尺度环流系统和青藏高原对天气尺度扰动生成发展和传播过程的影响。项目的成功实施将增进我们对中纬度天气尺度扰动的认识，并为江淮流域夏季短期降水预报提供新的参考依据。

中文关键词： 天气尺度扰动；江淮流域；夏季极端降水；结构特征；形成机制

英文摘要： The prediction of summer extreme rainfall over the Yangtze-Huai River Basin is always the hot topic of weather forecasters and scientists. The case study reveals that the midlatitude synoptic-time scale (3-8-day) disturbances are the key systems responsible for the occurrences of those extreme rainfall events. However, these disturbances were mostly removed in previous extreme rainfall studies because they were regarded as high frequency noises. These situations inspire the ideas for this project. Based on 29-year rainfall and circulation data, this project will try to investigate the following issues from the aspect of climate statistics. First, the propagation tracks and three dimentional structural characteristics of the synoptic-time scale disturbances associated with the Yangtze-Huai River Basin summer extreme rainfall will be explored. Then, the influence of these disturbances on summer extreme rainfall events over the Yangtze-Huai River Basin will be studied in detail, including the interactions between disturbance and Meiyu front, as well as the moisture transportation contribution from disturbances to extreme rainfall. Furthermore, the roles of East Asian large-scale background circulation systems and the Tibetan Plateau in regulating the synoptic-time scale disturbances' origins and energy dispersions will also be investigated. The successful implementing of this project will enhance the understanding of midlatitude synoptic-scale disturbances and provide new references for the short-term summer rainfall forecast over the Yangtze-Huai River Basin.

英文关键词： synoptic-time scale disturbances;Yangtze-Huai River Basin;summer extreme rainfall;structural characteristics;formation mechanism