福建冰雹的气候统计特征

The Climatic Statistic Characterstic of Hailstone in Fujian

利用福建1960～1999年的观测资料和1980～1999年的欧亚高空探测资料，分析了福建冰雹的时空分布特征和春季降雹的天气气候特征，结果表明：福建冰雹灾害的季节变化存在明显双峰现象。主峰在早春，次峰在盛夏，地理分布内陆多于沿海，山区多于平原。造成春季降雹的天气型主要为冷切适中型、低涡冷切适中型、低涡切变偏西型、冷切偏南型、冷切偏西型。福建省春季冰雹的主要机理是冷空气与强暖湿气流相遇而引发的。高空西风槽和南支槽及其前侧的副热带急流和低空强西南急流及准静止切变线是诱发福建省春季冰雹天气最主要的天气系统。

The spatial and temporal distribution of hail and the climatic characteristics of hail in springtime were analyzed with making the surface observational data in Fujian from 1960 to 1999 and the radiosonde observational data in Eurasia from 1980 to 1999.It shows that there are double apexes through the seasonal fluctuation of hail disaster in Fujian. The main apex in early spring,The second in midsummer.The geographic distribution of hail is more in midland than in littoral,and more in mountain area than in plain area.The main weather types which engender hail in spring are as below：the moderate cold shear type,the moderate vortex and cold shear type,the westward deflection vortex and cold shear type,the southward deflection cold shear type, and the westward deflection cold shear type.the southward deflection cold shear type,and the westward deflection cold shear type.The mechanism is caused by cold air and strong warm moist air effect altogether.The weather system is mainly composed of the upper-level westerly trough and the southern branch trough as well as the subtropical jet,strong low-level southwest jet and quasi-stationary shear line.