Spatial and Temporal Evolutionary Characteristics of Extreme Precipitation and It's Estimation for Certain Return Period in Hunan Zishui River Basin
LI Bing1
ZHANG Xinping2
YANG Ling1
XIA Yan3
Abstract:【Objective】The purpose of this paper is to analyze spatial and temporal evolutionary characteristics of the values of extreme precipitation for each national meteorological observatory of certain return periods in Zishui river basin, 【Method】 based on the observed daily rainfall data from 1960 to 2016, the values of extreme precipitation for each national meteorological observatory of certain return periods were calculated using EOF, spatial auto correlation, Mann-Kendall test, Complex Morlet wave transform and statistical methods. 【Result】The results showed that: ①generally speaking, spatial distribution of the extreme precipitation in Zishui river basin is inhomogeneous which is greater in the west than the east and greater in the north than the south. There are three kinds of typical modes for extreme precipitation, namely the whole region, north-south, northwest-southeast. Annual maximum daily precipitation was characterized of spatial aggregation since 1980s, the tend of polarization is very obvious after 2000.②The value of extreme precipitation has increasing tendency, this is especially true for middle and downstream. There exist a 10 years Quasi-periodic oscillation for extreme precipitation in upstream.③When the return period is greater than 50 years, the spatial distribution of extreme precipitation is still inhomogeneous which is larger in the west than the east and larger in the north than the south. The extreme precipitation of certain return period increases with the increasing of return period. The more extreme precipitation, the faster extreme precipitation increases. 【Conclusion】 The occurrence of El Nino in recently years were thought to be connected with the evolution of extreme precipitation. The relations between El Nino and extreme precipitation of Zishui basin are remain to be discussed.
Keywords:Zishui river basinextreme precipitaionspatial and temporal evolutionreturn period
Publication Date:2019-11-28
Online Publishing Date:2026-09-12(First online date of this platform, not the publication date of the document)
Pages:12( 117-128 )
