强热带风暴碧利斯造成华南持续大暴雨成因分析

统计分析了山东省枣庄1958～2005年逐日及逐月降水资料,发现20世纪50年代末期到60年代中期鲁南为多雨期,60年代中期到60年代末期有一个短暂的少雨期,70年代初中期有一个短暂的多雨期,70年代中期到90年代末期是一个较长时段的降水偏少期.2000年以后进入多雨时期,2000、2003及2005年出现局部洪涝灾害.文章引入相当暴雨日数的概念,研究了相当暴雨日数与大涝、大旱年的关系,发现大涝、大早年的降水量更取决于汛期相当暴雨日数的多少;用相当暴雨日数和年降水量建立回归方程,在一定程度上,相当暴雨日数能很好地预测当年旱涝.

Analysis of Heavy Rains in Flood Season and Their Climatic Background in Southern Shandong

By means of the conventional observation data and NCEP reanalysis data, the sustained torrential rain event caused by the severe tropical storm Bilis (0604) is investigated. The results show that the strong vapor transport and updrafts originated from strong convergence at the low level under the persistent interaction of the tropical storm and southwest monsoon the south of Bilis, as well as the zones of convergence at the low level, divergence at the high level, updraft and high intensity vapor convergence, are rarely reported for recent years, although Bilis is only a severe tropical storm from its intensity. The rainstorm center is well corresponded with the location of the strong vapor convergence. The rainstorm event is closely related to the slow movement of the typhoon low pressure system and the sustained interaction with southwest monsoon.