台州1981~2010年内陆局地性暴雨气候特征分析

利用NCEP、fnl再分析资料和常规探测资料分析1981~2010年台州市局地暴雨的时空分布，并进行天气分型，对平均形势和典型个例进行了对比分析.结果表明：（1）台州局地暴雨日约占总暴雨日数的1/3，月际变化显著;局地暴雨总体上呈北多南少分布；（2）5~6月暴雨主要由西风带类造成，8~9月主要由东风带造成，7月各类暴雨均有发生.热带系统、移动低槽、南海台风是引发台州局地暴雨最多的系统.局地暴雨对于水汽输送和动力条件的要求比大暴雨要低得多.各型范围暴雨和局地暴雨在850 hPa形势场上有较明显的差异；（3）越大的降水其局地性越强：局地暴雨、大暴雨、特大暴雨占总的暴雨、大暴雨、特大暴雨日数比例逐级上升.

Analysis on the climate characteristics of local rainstorm in inland Taizhou from 1981 to 2010

Based on NCEP, fnl reanalysis data and conventional obserrations, the spatial and temporal distribution and circulation types of local rainstorm in inland Taizhou from 1981 to 2010 were studied, and the averaged circulation of each type and typical case were analysed. The results show that:(1)The local rainstorm days account for 1/3 of the total number of rainstorm days in Taizhou, and it has a significant monthly variation. Local rainstorms occur more frequently in northern Taizhou than in southern area.(2)Rainstorms in May June are mostly caused by westerly systems, while rainstorms in August September by easterly systems. All types of the rainstorms occur in July. Tropical system, migrating trough, typhoons over the South China Sea are the main systems that cause local rainstorms in Taizhou. Compared with the large area rainstorm, the local rainstorms have a much lower request of water vapor transport and dynamical condition. Large area rainstorms and the local rainstorms obviously differ in circulation at 850 hPa. (3) The greater precipitation is, the more local its area will be.