太行山和山东半岛地形对冷流暴雪的影响分析

用WRF模式模拟了2005 年12 月6-7 日山东半岛一次冷流暴雪过程，通过降低太行山地形高度至10 m和抬升山东半岛地形高度至500 m的敏感性数值试验，分别分析了上游太行山和本地山东半岛地形对山东半岛冷流降雪的影响。结果表明：太行山对山东半岛冷流降雪的强度起到了加强的作用，降低太行山地形高度的敏感性试验在山东半岛北部10 m风场辐合强度较同时次控制性试验明显减弱，减弱的区域主要在山东半岛北部地区，其他区域变化不明显；同时敏感试验的流场在山东半岛的辐合也有所减弱，流线密度要疏散些。850 hPa西北风越过太行山后在背风面产生波动，波动中的气旋性小涡旋移至山东半岛后，加强了山东半岛本地的辐合强度。抬升山东半岛的地形高度后，地形的抬升辐合作用增强，故冷流降雪的强度也得到增强。

Effects of topography of the Taihang mountains and Shandong peninsula on the cold airflow snowstorm

A cold airflow snowstorm process on December 6-7 ,2005 in the Shandong peninsula was simulated u-sing a WRF model.By reducing the height of the Taihang mountains down to 10 m and uplifting the height of the Shandong peninsula to 500 m,a sensitivity experiment was performed to analyze the effects of topography of the Taihang mountains and Shandong peninsula on cold airflow snowstorm.The results indicate that the intensity of cold airflow snowstorm in the Shandong peninsula increases because of the existence of the Taihang mountains. The convergence intensity of 10 m wind field in the sensitivity experiment by reducing the height of the Taihang mountains is weakened obviously compared with that in the control experiment,especially in the north of the Shan-dong peninsula.At the same time,the convergence of flow field in the Shandong peninsula is weakened simultane-ously as the stream become diverging.A wave is generated as the northwest wind at 850 hPa crosses over the Taihang mountains,and the vortex in the wave strengthens the local convergence by moving downstream to the Shandong peninsula.As the raising of height of the Shandong peninsula enhances the effects of uplifting and con-vergence,the cold airflow snowstorm is strengthened consequently.