Analysis on Spatial and Temporal Changes of Extreme Precipitation Events in Ningxia in Recent 50 Years

• 作者: LI Xin
• 来源期刊: 气象与环境研究：英文版
• 学科: 地球科学
• 关键词: 降水事件 时空分布 宁夏 变化分析 年平均降水量 极端降水 降水强度 统计检验方法
• 年，卷（期）: 2012,（6）
• 页码范围: 22-25
• 页数: 4页
• 分类号: P532

摘要

[Objective] The aim was to study the spatial and temporal changes of extreme precipitation events in Ningxia in recent 50 years.[Method] Using daily precipitation data at 20 stations in Ningxia from 1961 to 2010,and defining the threshold value of extreme precipitation in each station by percentage method,choosing indicators such as precipitation,frequency and intensity of extreme precipitation events,the characteristics of the spatial and temporal distribution and linear trend of extreme precipitation events in Ningxia were analyzed based on linear regression and M-K non-parameter statistical test method.[Result] The percentage method suggested the threshold value of average extreme precipitation in Ningxia in recent 50 years decreased from south to north.The large threshold value was in southern Haiyuan,Tongxin and northern Yancheng,which was similar to the distribution of mean annual precipitation in Ningxia.In recent 50 years,extreme precipitation frequency and extreme precipitation decreased in most part of Ningxia but the intensity tended to strengthen.Study of extreme precipitation in Mahuang Mountain and Liupan Mountain indicated that precipitation frequency,intensity and extreme precipitation reduced.Annual extreme precipitation frequency narrowed and then increased after 1994 and had mutation in 2003.Annual extreme precipitation intensity enhanced since 1984.Mutation took place in 1984.Intensity in Liupan Mountain had weakened since 1978.[Conclusion] The study provided theoretical basis for the mutation of climate in Ningxia.