摘要
分析了2006年4月28日发生在临沂的罕见灾害性大风的多普勒天气雷达产品。分析发现,雷达回波具有典型的弓状回波特征,在弓状回波前沿,对流单体强烈发展,出现有界弱回波区,低层入流缺口等超级单体的典型特征,风暴中出现中气旋,强降水之后风暴回波顶高、风暴质心高度、风暴的最大反射率因子高度迅速下降,灾害性大风出现在这个时段。实地考察表明,灾害性大风的路径与中气旋最大风速圈南缘移过的路径一致。分析认为,弓状回波后部存在较强后部下沉入流,由于强降水的拖曳作用,将中层中气旋的水平动量带到地面,中气旋右侧动量的方向与弓状回波后部的强下沉入流方向一致,两者叠加,使地面风速加大,造成灾害性大风。
Doppler radar products of damage wind process in Linyi, Shandong on 28 April 2006 were analyzed. The echo was a typical bow echo, in the front of the bow echo a super-cell developed with ＂V-NOTCH＂, BWER, then meso-cyclone and heavy rain occurred. After heavy rain, the top of the storm, the height of storm centroid and maximum reflectivity fell rapidly. The damage wind occurred at this time. Investigated data shows that the path of damage wind go a- long with the path that the right edge of the meso-cyclone passed. It suggests that the horizontal momentum of the meso-cyclone was brought down to the surface by heavy rain. At the right edge of meso-cyelone the momentum and RIF have the same direction, the two airflows overlay together and make the wind increase, so damage wind occurred.
出处
《气象》
CSCD
北大核心
2008年第12期21-26,I0001,共7页
Meteorological Monthly
基金
国家自然科学基金项目(40575012)
山东省气象局科学技术研究项目(2007sdqxz04)共同资助
