江淮气旋暴雪天气的形成机制及预报技术研究

Jiang-Huai cyclone is one of the most important weather systems that can cause snowstorms in the south of north China, the north of east China and northeast China, in which Shandong province frequently. This kind of snowstorm is characterized of broad spatial extent, high precipitation intensity, long duration, complicated precipitation types and variable heavy snowfall distribution. So it is difficult extremely to predict accurately snowstorm caused by Jiang-Huai cyclone. The subject is planed to use all sorts of new observational data, WRF-3DVAR numerical simulation and EVAP wind field retrieving technology to study, including satellite, Doppler radar, wind profiler radar, automatic meteorological station, solid automatic observation, microwave radiometer, GPS/MET and such like. Comprehensive studies are about to develop on the character and mechanism of spatial structure, circulation, snow and rain distribution, meso-scale structure and precipitation types . Meanwhile, physical conceptual model will be built.In the end, it's hoped to summarized key forecasting technology and index about precipitation types, location, intensity, peak times, start and end time by all kinds of data. With the achievement of the project, forecasting accuracy on snowstorms will take a chance to be improved in the future.

江淮气旋是造成华北南部、华东北部和东北地区冬季暴雪的重要天气系统之一，以山东最为常见。江淮气旋暴雪具有范围广、强度大、持续时间长、降水相态复杂、强降雪中心多变等特点，因此实现精细化预报难度较大。本项目充分利用多种新型探测设备（包括卫星、多普勒天气雷达、风廓线雷达、固态降水自动观测站、微波辐射计、GPS/MET等）获取的高时空分辨率资料，结合常规观测和NCEP/NCAR再分析资料，采用WRF-3DVAR同化系统数值模拟、雷达EVAP风场反演和多资料融合等方法，系统研究不同路径江淮气旋暴雪天气系统的空间结构、环流形势及雨雪分布特征，建立三维概念模型；探索地形对江淮气旋系统及其产生的降雪天气的影响，揭示中尺度结构特征及发展机制；研究降水相态特征及其发生机制；总结相态转换、降雪落区、强度、强降雪时段和起止时间在各种资料的征兆信号，凝练关键预报技术和指标，为提高暴雪天气的预报准确率提供科学依据。

江淮气旋是造成华北南部、华东北部和东北地区冬季暴雪的重要天气系统之一， 以山东最为常见。江淮气旋暴雪具有范围广、强度大、持续时间长、降水相态复杂、强降雪中心多变等特点，因此实现精细化预报难度较大。本项目充分利用卫星、多普勒天气雷达、风廓线雷达、称重式自动观测站、雨滴谱仪等多种新型探测设备获取的高时空分辨率资料，结合常规观测和NCEP/NCAR再分析资料，采用WRF数值模拟等方法，系统研究了江淮气旋暴雪过程的天气特征、高低空配置，构建了天气概念模型；阐述了中尺度结构特征及其发展机制，通过统计分析和敏感性试验发现鲁中山区地形对强降雪的影响；提出了江淮气旋降水相态的预报指标；揭示了“雷打雪”的形成机制；构建了关键预报技术，凝练出降雪落区、强度、强降雪时段和起止时间及降水相态转换等的征兆信号；建立了暴雪个例库和查询系统。项目研究成果为提高暴雪天气的预报准确率提供了技术支撑。