不同参数化方案对风预报效果影响个例研究

Impacts of Different Parameterization Combination Schemes on Wind Forecast

中尺度气象模式对风场的预报效果与参数化方案的适应性紧密相关。以内蒙古高原丘陵地形、江苏平缓的海陆交界地形2种典型下垫面试验风电场为模拟区域,分别用WRFV3.2(Weather Research and Forecast Model)模式自带的6种物理过程参数化组合方案预报了2010年1月和7月两个风电场区域的风速和风向,对比分析了参数化组合方案差异对风场预报的影响。结果表明:①内蒙古试验区,边界层MRF方案描述的边界层结构较MYJ方案合理;微物理方案WSM3在夏季的风速预报能力优于WSM6,而冬季相反;复杂地形区域的风场预报需考虑陆面过程参数化方案,尤其是夏季降水发生后,陆面过程对于边界层结构的影响增大,选用Noah优于无陆面过程。②江苏试验区,边界层MRF方案描述的边界层结构较MYJ方案合理;1月陆面过程RUC方案优于陆面热量扩散和Noah;7月陆面热量扩散方案优于RUC和Noah。③风向预报6个方案的预报风向统计与实际记录风向统计有较好的一致性,风向概率分布相似,盛行风向一致且稳定。

The wind forecasting results of the mesoscale meteorological model are closely related to the adaptability of the parameterization schemes. Two pilot wind farms with typical underlying surface are selected as simulation regions, which are the undulating hilly terrain of Inner Mongolia and the flat land- sea border terrain of Jiangsu respectively. Six kinds of physical process parameterizations of WRFV3.2 （Weather Research and Forecast Model） are adopted in forecasting the wind speed and direction of the two wind farms in January 2010 and July 2010, and the impacts of parameterizations difference on wind forecasting are analyzed. The results show that ： （1） In the experimental area of Inner Mongolia, the MRF boundary Layer parameterization scheme is more reasonable than MYJ does in describing the structure of the boundary layer; the microphysical scheme WSM3 forecasts the wind speed better than WSM6 in summer and vice versa in winter; the land surface process scheme increases the influence on the boundary layer structure of complicated terrain, especially after summer rainfall, and the Noah scheme is better than that without any land surface process. （2） In the experimental area of Jiangsu, the MRF boundary Layer parameterization schemes describes the structure of the boundary layer more reasonable than MYJ; the land surface process RUC is superior to the heat diffusion and Noah schemes in January; the heat diffusion scheme is superior to the RUC and Noah in July. （3） The forecasting wind direction statistics of the six parameterization combination schemes and the actual recorded wind direction statistics are in good agreement, and the wind direction probability distribution is similar, and the prevailing wind direction is consistent and stable.