潍坊市近 50年夏季暴雨气候特征分析

为了能更好地研究和分析潍坊夏季暴雨的气候特征,从而提高夏季暴雨的预报准确率,更好地服务于当地的气象防灾减灾工作,利用潍坊10个观测站1961—2010年的夏季逐日降水资料,对潍坊地区夏季暴雨的空间分布特征和时间演变规律进行分析,并对各类暴雨与各种影响天气系统之间的关系进行统计。结果表明,在空间分布上,由东南向西北逐渐递减的地域特征十分明显;在时间分布上,潍坊夏季暴雨的年平均发生日数为7.5天,7月最多,8月次之,6月最少,并且潍坊夏季暴雨的年际间变化较大,暴雨日数以平均0.76 d/10 a的速率下降,下降趋势比较明显;自20世纪60年代—20世纪末,潍坊暴雨日数呈减少趋势,20世纪末21世纪初有增多趋势,但趋势不是很明显,并且在1996年发生突变;低涡、切变线是造成潍坊夏季暴雨的主要系统,其次是低槽冷锋暴雨,这2种类型的暴雨,主要是以局地暴雨为主,很少产生大范围暴雨;气旋暴雨与台风暴雨相对较少,但这2种类型的暴雨多产生区域暴雨与大范围暴雨。

Analysis of Climate Characteristics of Summer Rainstorm in Weifang in the Last 50 Years

In order to study and analyze the climate characteristics of summer rainstorm in Weifang, so as to improve the summer rainstorm forecast accuracy, and better service to the local meteorological disaster prevention and mitigation, by using summer daily precipitation data of Weifang 10 observatory from 1961 to 2010, the spatial distribution characteristics of summer rain in Weifang and the time evolution law and all kinds of heavy rain and the statistical relationship between all kinds of weather modification system were analyzed. The results showed that: the phenomenon that heavy rains often from southeast to northwest was gradually decreased was obvious on the spatial distribution; in the time distribution, summer storm of annual average days was 7.5 days. June July, and August was to a minimum; heavy rain days with an average of 0.76 d/10 a rate decreased, the decrease was more noticeable; low vortex, and shear line was the main system in Weifang summer rain, followed by low trough cold front rainstorm, and the mainly local rainstorm was given priority to, rarely produces a wide range of heavy rain; cyclone rainstorm and typhoon torrential rain were relatively small, but the two types of heavy rains were more regional heavy rain and a wide range of heavy rain.