基于小波函数湛江市气象干旱周期分析  

Analysis of Meteorological Drought Cycle Based on Wavelet Function in Zhanjiang

作　　者：张得胜 陈雅芬 谭森明 ZHANG Desheng;CHEN Yafen;TAN Senming(Comprehensive Technology Center of Pearl River Water Resources Commission of the Ministry of Water Resources,Guangzhou 510611,China)

机构地区：[1]水利部珠江水利委员会珠江水利综合技术中心,广东广州510611

出　　处：《人民珠江》2020年第7期18-24,43,共8页Pearl River

摘　　要：选取广东省湛江市作为研究区域,基于区内19个雨量站1966—2015年逐月降雨序列数据,采用6个月时间尺度的标准化降水指数,结合旋转经验正交分解法对区域气象干旱分布进行空间模态分解,利用小波分析对不同空间模态对应的区域进行干旱周期求解。结果表明:湛江市干旱空间分布可分解成6个空间模态,不同模态对应不同区域,区域内干旱周期主要信号最强为9.3 a、最弱为2.1 a,6个模态普遍存在2~6 a震荡周期,与实际干旱发生的周期基本一致。湛江地区干旱呈现周期性变化的原因与厄尔尼诺事件有关,春季降雨和厄尔尼诺的关系更密切,厄尔尼诺对春旱的影响更为持续和显著。Based on monthly rainfall data of 19 stations from 1966 to 2015 in Zhanjiang City,Guangdong Province,which is selected as the research area,this paper conducts the spatial modal decomposition of regional meteorological drought distribution by using the standardized precipitation index of 6 months and the rotated empirical orthogonal function,and calculates the drought period of different spatial modes through wavelet analysis.The results show that the spatial distribution of drought in Zhanjiang can be decomposed into 6 spatial modes.Different modes correspond to different regions.The strongest signal of the drought cycle in the region is 9.3 a and the weakest is 2.1 a,and there are 2~6 a oscillation periods in different modes,which are basically consistent with the actual drought cycle.The reason for the periodic variation of drought in Zhanjiang is related to the El Nino event.The relationship between spring rainfall and El Nino is more closely related,and the impact of El Nino on spring drought is more sustained and significant.

关 键 词：气象干旱 标准化降水指数 旋转经验正交分解 小波函数 干旱周期 湛江市 

分 类 号：P429[天文地球—大气科学及气象学]