基于数值模式的风场时空变化特征的统计分析

统计分析风场时空变化的特征,掌握其变化规律,可以提高风场预报的准确性。利用WRF模式对大气状态进行模拟,优化配置物理过程参数化方案,采用多层嵌套、双向反馈。以2 h为时间间隔的风场状态变化作为统计的风差样本,重点关注超过规定阈值大小的显著风差样本的分布,将风差样本标注在地图上,制作显著风差样本图。统计了显著风差样本数量在一天中的累积分布、风差样本的大小在垂直方向的分布,以及风场状态在各个高度层之间的差别。选择银川河东机场区域作为WRF模拟区域,对该区域一年的风差样本进行统计分析。结果表明:复杂地形条件下,不同区域风场变化的剧烈程度有很大的差别,但由同一因素引起的显著风差样本的变化趋势是一致的;风场时空变化的剧烈程度随着高度的增加而减弱。

Statistical analysis of temple and spatial changes in wind based on numerical model

The statistical analysis of the temple and spatial changes in wind can improve the precision of the forecast of the wind field. Weather research and forecast (WRF) model was used to simulate the atmosphere station, with optimized parameterization schemes and two way nesting. The temple changes of wind between 2　h were defined as the wind change samples, and the significant wind change samples which exceed a threshold were especially concerned. Wind change samples can be plotted on a map and then the map of significant wind change sample is produced. Time series of the number of significant samples, the vertical distribution of the sample magnitude and the spatial difference of wind between each altitude were analyzed statistically. The result from the year long simulation at the area of Yinchuan Hedong Airport was selected as the data to analyze the features of wind changes. It is demonstrated that in the condition of complex terrain, the temple changes are different significantly at different points, but the significant samples conducted by the same factors move coherently; and chat the intensity of the temple changes decreased with the increase of altitude.