Abstract:

Based on daily precipitation observations from 1962 to 2011 at 97 meteorological stations in Hu’nan Province，the annual variation characteristics of different level precipitation in recent 50 years in Hu’nan were analyzed by using the cumulative anomaly percentage，climate tendency rate，Mann － Kendall test，R/S and Morlet wavelet analysis methods． The major results include that the tendency of each grade annual precipitation except the small rainfall in Hu’nan Province presented increasing trend; there were two high value center ( the middle and the southwest region of Hu’nan) and one low value center ( northwest region of Hu’nan) about the climate tendency rate of different grade annual precipitation． The time of abrupt change for each grade annual rainfall was different，for small rainfall it was earlier than that of strong rainfall． And the change period for each grade annual precipitation was different，but the three － year period was in common for each grade rainfall since 1990．

Key words: Hu’nan Province, different grade precipitation, climate tendency rate, change trend

摘要：

利用湖南97 个气象站1962 ～ 2011 年的逐日降水量资料，根据日降水量将降水分为小雨、中雨、大雨、暴雨、大暴雨等量级，通过累计距平百分率、气候倾向率、Mann － Kendall 检验、R/S 分形分析以及Morlet 小波分析等方法，对湖南近50 a 各量级降水的年变化特征进行了分析。主要结果包括:全省平均状况而言，除小雨量级外的其他量级年降水量均有增加趋势; 湖南各量级降水的年降水量气候倾向率有2 个高值中心( 湖南中部、湖南西南部) 和1 个低值中心( 湖南西北部) ; 各量级降水的突变时间出现时间不一致，弱降水量级的突变早于强降水量级; 各量级降水量的变化周期各不相同，1990 年后3 a 左右的周期在各量级降水中表现都较明显。

关键词: 湖南, 各量级降水, 气候倾向率, 降水变化趋势