鄱阳湖流域1961—2010年极端降水变化分析

基于鄱阳湖流域14个国家气象站1961—2010年的日降水量数据,采用百分位法定义阈值,识别极端降水事件;采用线性回归方法进行趋势检验,进而对鄱阳湖流域1961—2010年极端降水的时空变化特征进行分析。结果表明,相比年降水,流域极端降水的变化趋势更为明显;1961—2010年鄱阳湖流域极端强降水强度呈显著增大趋势而极端强降水天数显著减小;极端降水强度增大的区域主要分布在赣江流域和抚河流域。1961—2010年鄱阳湖流域大部分站点极端降水不存在突变,降水在时间上有分布更加集中的趋势。鄱阳湖流域极端降水的上述变化,对流域水资源管理提出了更加严峻的挑战。

Changes of extreme precipitation events in Poyang Lake Basin from 1961 to 2010

Based on the daily precipitation records at 14 national meteorological stations in Poyang Lake Basin from 1961 to 2010, extreme precipitation events were identified using a threshold determined with the percentile method. The spatial and temporal changes of extreme precipitation were analyzed, and the trends were examined through linear regression. The results show that, during the period from 1961 to 2010, extreme precipitation showed larger changes than annual precipitation. The intensity of extreme heavy precipitation showed a significantly increasing trend, while the duration of extreme heavy precipitation events showed a significantly decreasing trend. The areas showing a significantly increasing trend were mainly located in the Ganjiang Basin and Fuhe Basin. Extreme precipitation in most stations in the Poyang Lake Basin did not show abrupt change. The extreme precipitation events showed a more concentrated trend on a temporal scale. These changes of extreme precipitation events will lead to more serious challenges for water resources management in the Poyang Lake Basin.