Anomaly Characteristics of Extreme Precipitation over Chongqing in Flood Season during 1961-2006

Abstract:

Based on 1961-2006 daily precipitation data during flood season(from May to September) of 33 stations in Chongqing,by defining the extreme rainfall threshold,study is performed of the annual gross precipitation and the temporal/spatial distribution features of each station in the study period,results show that in flood season Chongqing has the significant spatial distribution differences in extreme rainfall,and the consistently abnormal characteristic is the main spatial mode;Chongqing can be divided into five regions;and the extreme rainfall covers a very large proportion of the total rainfall in each region;and from a long-term trend,the precipitation in Chongqing area does not show significant increasing or decreasing trend,and for the recent 46 years the periodic oscillations of extreme precipitation are dominated by 2-3-year,5-year periods,and about 11-year period.

Key words:Chongqing;flood season;extreme precipitation;time/spatial distribution