连云港市暴雨天气形势分析

Statistical analysis on rainstorm weather in Lianyungang city

用连云港市7个气象观测站的常规观测资料,对1971—2008年的38 a中29次区域性暴雨天气过程进行数理统计,对连云港市的暴雨天气变化趋势进行探讨,连云港市暴雨天气主要发生在6—9月,7—8月次数最多,占总数79%,雨量极值出现在西连岛站,暴雨日数及雨量极值趋于增大且趋势比较明显。同时,对全市区域性暴雨天气的高空影响系统进行了分类,划分为4种类型:台风减弱型、低压型、横槽类型、低槽类型,各类型几乎各占总暴雨数的1/4。

The observation station and the weather chart data in Lianyungang city during 1971—2008 and the mathematical statistics method were applied to preliminarily discuss rainstorm weather trend in Lianyungang city.Rainstorms occurred mainly from June to September,especially in July and August,in fact,79% of rainstorms belonged to this period.The extreme rainfall appeared at the Xilian Island Station.Moreover,days of heavy rain and rainfall extremes tend to increase,and this kind of trend becomes more and more obvious.At the same time,the upper-level effect system in regional heavy rain weather of the whole city can be classified into four types： the weakened typhoon type,low pressure type,transverse trough type,low trough type.The proportion of each type accounts for almost 1/4 of the total number of rainstorm.