摘要
应用全球格点资料,利用中尺度数值模式WRF对2012年4月11日出现在宁夏境内的大到暴雪天气进行了数值模拟,模拟结果显示:WRF模式可以较好地模拟出强降雪的分布。诊断分析结果进一步表明,700 hPa西南急流、850 hPa东北急流的形成,为强降雪的发生提供了充足的水汽条件。强降雪期间,由于低空辐合较强,导致上升运动加强,500 hPa以下水汽辐合量明显增加,中低层的水汽充沛,垂直速度负值区维持及强度增强,由此产生的垂直方向上水汽凝结是这次强降雪的形成机制,为大到暴雪的产生提供了有利条件。
A numerical simulation was made on the blizzard process within Ningxia in April 11, 2012 using mesoscale numerical model WRF and global grid point data. The simulation result showed that the WRF model could simulated the distribution of the heavy snowfall better. The result of the diagnostic analysis further showed that the formation of the 700 hPa southwest jet and 850 hPa northeast jet provided an adequate moisture conditions for the occurrence of the heavy snowfall. During the heavy snowfall process, due to a strong low level convergence that leading to a stronger ascending motion, the amount of water vapor convergence below 500 hPa increased significantly, the low layer was filled with moisture, the negative zone of the vertical velocity maintained and strengthened, the water vapor condensation in the vertical direction causing by these was the mechanism of the formation of the heavy snowfall. It provided a favorable condition for the occurrence of the blizzard.
出处
《宁夏农林科技》
2013年第8期66-68,共3页
Journal of Ningxia Agriculture and Forestry Science and Technology
