1961年以来海南岛降水变化趋势分析

Analysis For Precipitation Change Trend Of Hainan Island Since 1961

应用趋势分析法和聚类分析法等方法分析了海南岛全岛各站点1961～2004年雨量和雨日分布特征及其变化规律。结果表明：全岛年降水主要集中在5～10月份；年均雨量最多在中部和东部沿海地区，其中琼中最高（2438．9mm／a）；最少在西部沿海地区；不同等级降雨雨日分布与雨量基本一致。从年际变化看，全岛年雨量、早期雨量、汛期雨量均呈增加的趋势；全岛平均年降雨日数、毛毛雨日数以及年最长持续降雨日数均呈逐渐减少的趋；而全岛多年平均年大雨日数、暴雨日数则呈逐渐增加的趋势。

This paper analyzes the annual precipitation and the rainy days distribution characteristic and their change rule during 1961～2004 in the various stations of Hainan Island by using tendency analytic method, gathered methods and so on. The result indicates that the precipitation of the entire island mainly concentrates from May to October. The yearly average rainfall is most in middle and eastern part of the coastal area, and highest in Middle part （2438. 9mm/a）, and the least in western coastal area. The rainy day distribution of different grade rain measurement with the rainfall are basically consistent. Regarding to the yearly change, the annual precipitation, the precipitation in drought period, the precipitation in flood season assume an increasing tendency in the entire island; The average yearly rainy day number, and the drizzle day number as well as the yearly longest continual rainy day number assume gradually reducing tendency, But the multi-year average heavy rain and rainstorm day number present the gradually increasing tendency.