湖南省不同时间尺度SPI干旱特征研究  

The Research on Drought Characteristics of SPI at Different Time Scales in Hunan Province

作　　者：吴浩 张剑明[2] 颜鹏程[1] 曾宇星[2] 段丽洁 Wu Hao;Zhang Jianming;Yan Pengcheng;Zeng Yuxing;Duan Lijie(Institute of Arid Meteorology,China Meteorological Administration,Lanzhou 730020;Hunan Climate Center,Changsha 410118)

机构地区：[1]中国气象局兰州干旱气象研究所,兰州730020 [2]湖南省气候中心,长沙410118

出　　处：《气象科技进展》2021年第2期139-147,共9页Advances in Meteorological Science and Technology

基　　金：2017年度中国气象局干旱气象科学研究基金项目(IAM201708);国家自然科学基金项目(42005058);湖南省自然科学基金项目(2020JJ5298)。

摘　　要：选取湖南省97个国家气象观测站1961—2016逐月降水资料,采用统计方法,构建了湖南省的月、季、年尺度的标准化降水指数(SPI),并利用SPI指数分析了湖南省不同时间尺度干旱特征。结果表明:湖南省多年平均年尺度干旱发生站次为30.7站,多年平均季尺度干旱发生站次为30.5站,多年平均月尺度干旱发生站次为30.7站,三者相差很小;无论是年尺度、季尺度还是月尺度的湖南省SPI干旱指数都存在较为明显的年代际变化,都存在明显的干—湿—干—湿变化;总体来说年、季、月尺度湖南省都可以分为全省一致旱涝分布型、南北反向旱涝分布型,且前两个模态解释方差超过60%,能够代表不同时间尺度干旱的主要空间分布特征;对比分析不同时间尺度下的典型干湿年,能够发现湖南省2002年为全省一致湿润年、1997年为北旱南涝年、1969年和1998年为北涝南旱年。研究结果能够为湖南干旱的防灾减灾提供依据。Based on the monthly precipitation data of 97 national meteorological observatories in Hunan Province from 1961 to 2016,the SPI drought index of monthly,seasonal and annual scales was constructed by mathematical statistics method,and then the characteristics of drought at different time scales in Hunan Province were analyzed using SPI index.The results show that the average annual,seasonal and monthly scales drought occurrence stations in Hunan Province are 30.7,30.5 and 30.7 respectively,and the difference between them is very small.The SPI drought index of Hunan Province is obvious interdecadal variations and evident dry-wet-dry-wet variations at the all scales.In general,Hunan Province can be divided into the uniform drought-flood pattern and the reverse drought-flood pattern in the whole province at the different time scales,and the variance of the first two modes is over 60%,which can represent the main spatial distribution characteristics of drought at different time scales.By comparing and analyzing the typical dry and wet years in different time scales,it can be found that 2002 is the same wet year in Hunan Province,1997 is the year of north drought and south flood,1969 and 1998 is the year of north flood and south drought.The results can provide a basis for drought prevention and mitigation in Hunan Province.

关 键 词：湖南 SPI 变化特征 EOF 典型旱涝年 

分 类 号：P426.616[天文地球—大气科学及气象学]