农业工程学报2017，Vol.33Issue(10)：206-214,9.DOI:10.11975/j.issn.1002-6819.2017.10.027
基于游程理论和Copula函数的干旱特征分析及应用
Analysis and application of drought characteristics based on run theory and Copula function
摘要
Abstract
Drought is a complex and recurrent climate phenomenon, and understanding the development of the drought event is of great significance in preventing the damage. Current studies have analyzed the drought duration and severity based on run theory and Coupla function but few focuses on the drought recurrent interval and its relationship with agricultural drought disaster. In this study, the drought recurrence interval was investigated based on the drought duration and severity using run theory and Coupla function and the results were applied to agricultural drought disaster analysis in order to verify the reliability of the method for agricultural application. The study area was Northern Shannxi and the precipitation data from 1960 to 2015 were collected for drought grade classification based on standardized precipitation index (SPI). The drought duration and severity of drought event was calculated based on SPI values using run theory. Each drought characteristic index was evaluated for its distribution by comparing 7 different distributions. Then, the joint distribution of the 2 indices was established based on their correlation. Then the recurrence interval of each index was calculated for determination of their joint recurrence interval. The agricultural disaster area data were obtained from Statistic Yellow Book. The results showed that the drought occurred 94-103 times in 1960-2015 in the Northern Shannxi. The main drought area with high frequency was the area such as Yunlin, Yanan et al and that with low frequency was in the area such as Baoji, Xian, Xianyang et al. The distribution of drought duration and severity belonged to Weibull and Gamma distribution, respectively. The joint function of the 2 indices could be well fitted by the Frank-copula function with smaller squared euclidean distance and akaike information criterions. With the increase of drought duration and severity, the joint probability and recurrence interval gradually increased. The joint recurrence interval variation of different meteorological stations had different changing trend. The actual drought-affected area of the crops in the Northen Shannxi was closely related to the drought duration and severity. The drought events joint recurrence interval was coincide with the actual drought disaster situation in the region. In the period of 1995-2005, the actual and theoretical drought duration was consistent mostly and the absolute errors between the actual and theoretical drought recurrence interval were only 0.1-0.3 a. The results indicated that the method proposed here was reliable in analyzing drought characteristics and could be used for agricultural drought disaster assessment.关键词
干旱/降水/灾害/游程理论/Copula函数/干旱重现期/陕北Key words
drought/precipitation/disasters/run theory/Copula function/drought recurrent interval/Northern Shannxi分类
天文与地球科学引用本文复制引用
王晓峰,张园,冯晓明,冯玉,薛亚永,潘乃青..基于游程理论和Copula函数的干旱特征分析及应用[J].农业工程学报,2017,33(10):206-214,9.基金项目
国防科工委重大专项"黄土高原生态系统变化研究示范"(30-Y30B13-9003-14/16) （30-Y30B13-9003-14/16）
中央高校基本科研业务费高新研究项目(面向国家一、二类纵向预研项目)(310827162026) （面向国家一、二类纵向预研项目）
陕西省教育厅重点实验室科研计划项目(14JS010) （14JS010）
