基于EEMD的南京市降水特征分析
The Characteristic Analysis of Precipitation in Nanjing Based on EEMD Method
孙银凤 1陆宝宏2
作者信息
- 1. 河海大学水文水资源学院,南京210098
- 2. 河海大学水文水资源学院,南京210098;河海大学水文水资源与水利工程科学国家重点实验室,南京210098
- 折叠
摘要
论文采用EEMD分解方法分析了南京气象站1951-2009年降水序列的多时间尺度,发现南京市年降水序列存在2a、6～7 a、14～15 a和20 a的准周期变化,降水在20世纪70年代之前较小,70年代之后降水较大,整个时间尺度上呈现先减小后升高的平均变化趋势.综合运用Hurst指数及降水距平分析降水的趋势变化结果与EEMD分析结论基本吻合,未来南京市降水可能呈现减少趋势.另外用小波分析对EEMD提取的周期进行验证,小波分析表明南京市降水序列包含2a、7～9 a和15～16 a的准周期,与EEMD的结果基本一致,说明EEMD的结果具有一定的可信度,可以为该地区的降水预测提供依据.
Abstract
Based on the precipitation time series from 1951 to 2009 in Nanjing Weather Observation, ensemble empirical mode decomposition is used to analyze temporal scales and trend of the annual precipitation. The results show that the annual precipitation with short periods that last 2 years, and 6~7 years, as well as 20 years of long-term oscillation. Hurst index and the precipitation anomaly analysis reveal that the precipitation has a decrease trend before 1970, and then precipitation began to increase, lightly. Furthermore, the wavelet method was employed to analyze the precipitation period, it can be found that the annual precipitation has periods that last 2 years,7~9 years and 15—16 years, which are basically consistent with the EEMD results.
关键词
降水/多时间尺度/EEMD分解/趋势分析Key words
precipitation/multiple time scale/ensemble empirical mode decomposition/trend analysis引用本文复制引用
基金项目
国家自然科学基金(NSFC-50979023)
水利公益项目(201201026)
出版年
2013
国家科技期刊平台
NSTL
维普
万方数据