摘要
降水是干旱区水资源的重要组成部分,有效认识降水的区域变化规律对指导农业发展尤为重要。本文利用集合经验模态分解(EEMD)方法,分析了新疆降水变化趋势的多尺度特征。结果表明:新疆降水整体上呈现出非线性显著增多趋势,且其变化存在明显的年际尺度(3年和6年准周期)和年代际尺度(10年和31年准周期);各周期分量方差贡献率显示年际变化占据主导地位;降水年代际变化揭示了在1987年前后气候模态有了显著转换,由原来降水以负相位为主的气候模态转向正相位显著的气候模态。EEMD方法有助于人们对降水多尺度变化特征的认识,是一种适用于非线性、非平稳信号分析的有效方法。
Precipitation is an important part of water resources in arid areas,effective knowledge on precipitation regional change law is particularly important to guide agricultural development. In the paper,EEMD method is utilized for analyzing multi-scale characteristics of the precipitation change trend in Xinjiang. The results show that the precipitation in Xinjiang mainly presents a trend of nonlinear and significant increase. Changes are obviously available in interannual scale( 3-year and 6-year quasi-period) and decadal scale( 10-year and 31-years quasi-period). The periodic component variance contribution rate shows that interannual change occupies the dominant position; precipitation interdecadal change reveals that the climate model was prominently converted near 1987,which was converted from previous climate model with precipitation based on negative phase into climate mode with prominent positive phase. EEMD method can help people in understanding precipitation multi-scale change characteristics. It is an effective method applicable to nonlinear and nonstationary signal analysis.
出处
《水资源开发与管理》
2016年第4期47-50,共4页
Water Resources Development and Management
关键词
新疆
降水
EEMD模型
特征分析
Xinjiang
precipitation
EEMD model
characteristics analysis
