豫西丘陵地形对冰雹灾害落区的影响分析

利用三门峡市新一代多普勒天气雷达2006--2009年冰雹个例资料，结合豫西山区地形特征，分析了豫西丘陵地形对冰雹灾害的时空分布特征与落区的影响，结论如下：豫西地区每年都会发生雹灾多次，对当地经济作物危害很大；最早产生冰雹灾害的月份为5月，最晚为10月，其中以6月产生次数最多；冰雹灾害产生时间多在午后到傍晚，集中时段是在14—16时，傍晚之后的18—22时也有一个弱的峰值，而每日的6-12时没有产生过冰雹灾害．冰雹灾害影响范围比较小，最大直径（影响范围内两点间最大距离）一般不超过50km，大多数雹暴的雷达初始回波出现在降雹点的西北部，少数出现在降雹点的东北部、西南部或西部．豫西大部分地区都可能产生冰雹灾害。但在丘陵地形的影响下，有2个较集中的地带，一个在渑池县境内，另一个在卢氏县中北部到灵宝市南部地区．冰雹灾害落区均分布在山体的迎风坡上，且都在河流沿岸或附近．基于以上结论总结得到豫西山区冰雹灾害预报预警的重要着眼点及方法．

The Influence of Hilly Terrain in Western Henan on the Hail Falling Area

Using 2006--2009 hail data of Sanmenxia CINRAD/SB, combined with the feature of terrain in the mountainous areas of Western Henan, a statistical analysis is conducted on the influence of the Western Henan hilly terrain when hails occur on the spatial and temporal distribution characteristics of hail disasters and the hail falling area. The results show as follows. The hail disasters occur many times every year in Western Henan, which bring great harm to the local economic crop. The earliest month when the hail disasters occur is May, and the latest one is October, among them June is the most for the times. The hail disasters occur most in the afternoon, the mot concentrated period is at 14--16 o＇clock,the times during 18--22 o＇clock after the evening have a weak peak, and the hail disasters never occur during 6--12 o＇clock of day. The influence of hail disaster is relatively small, whose maximum diameter （the maximum distance between two points in the range of influence） is generally not more than 50 km. Most initial radar echo of hailstorm occurred in the northwest of hail falling area, and the minority in northeast, southwest or west. Hail disasters may occurred in most areas of Western Henan, but in the hilly terrain effects, there are two relatively concentrated areas,one in Mianchi County, another in the southern area of Lushi County and north central to Lingbao City. Hail disaster areas are all located in the windward slope of the mountain, and in the coastal or near the river. The important point and method are summarized in the mountainous areas of Western Henan hail disaster warning based on above conclusions.