黄土高原地区干旱可预报性的时空分布与驱动机理  

Spatial-temporal distribution and driving mechanism of drought predictability in the Loess Plateau

作　　者：王艺婷 黄生志[1] 黄强[1] 郑旭东 程立文 罗静[1] WANG Yiting;HUANG Shengzhi;HUANG Qiang;ZHENG Xudong;CHENG Liwen;LUO Jing(State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China,Xi’an University of Technology,Xi’an 710048,China)

机构地区：[1]西安理工大学西北旱区生态水利国家重点实验室,陕西西安710048

出　　处：《自然灾害学报》2024年第3期137-151,共15页Journal of Natural Disasters

基　　金：科技部重点研发计划项目(2022YFC3202303);国家自然科学基金面上项目(52279026);陕西省自然科学基础研究计划项目(2022-JC-LHJJ-05)。

摘　　要：变化环境下全球干旱频发,对社会经济与生态影响重大。已有研究重点关注干旱预报技术的研发,而对干旱预报的理论如干旱可预报性的时空分布与驱动机制等关注不足。以黄土高原为研究对象,构建支持向量机模型对2008—2019年区域干旱进行预测,并以预报效果克林-古普塔效率系数(Kling-Gupta efficiency,KGE)量化干旱可预报性,探究不同时间尺度干旱可预报性的空间分布特征、甄别了影响干旱可预报性分布变化的主导因素。结果表明:黄土高原地区干旱可预报性随着时间尺度的增大呈上升趋势,SPEI12的KGE比SPEI1提高73.8%,且季节干旱可预报性在秋季最高,其次为夏季、春季、冬季;干旱可预报性存在空间异质性,呈现北高南低的分布格局,春季黄土高原中部和冬季黄土高原西北荒漠区干旱可预报性极低;季节间干旱可预报性的主要影响因素存在差异,秋季q值最高的因子是气温,夏、春季是干燥度,冬季是海气耦合PRE_AMO;各变量因子双双交互后对干旱可预报性的影响力明显高于单因子。该研究为干旱可预报性提供了新的见解,有助于进一步提高黄土高原地区干旱预报预警能力。Under the changing environment,global drought occurs frequently,which has a great impact on social economy and ecology.Current researches focus on the research and development of drought forecasting technology,but pay little attention to the theory of drought forecasting,such as the temporal and spatial distribution and driving mechanism of drought predictability.This work took the Loess Plateau as the research object,constructed a support vector machine model to forecast regional drought from 2008 to 2019,and quantified drought predictability with Kling-Gupta Efficiency(KGE).Then the spatial distribution characteristics of drought predictability at different time scales were investigated,and the key factors influencing changes in the distribution of drought predictability were identified.The results showed that the drought predictability of the Loess Plateau showed an upward trend with the increase of the time scale.The KGE average of SPEI12 was 73.8%higher than that of SPEI1.The predictability of seasonal drought is the highest in autumn,followed by summer,spring and winter.The drought predictability showed spatial heterogeneity,showing a high distribution pattern in the north and low distribution pattern in the south,and the drought predictability in the central Loess Plateau in spring and in the northwest desert region of the Loess Plateau in winter was extremely low.There were differences in the main factors affecting the predictability of inter-seasonal drought.The highest explanatory power in autumn was temperature,summer and spring was aridity index(AI),and winter was the coupling of air-sea PRE_AMO.Meanwhile,the influence of both variable factors on drought predictability of the Loess Plateau was significantly higher than that of single factor.This study provided a new insight into the predictability of drought and was helpful to further improve the ability of drought forecasting and early warning in the Loess Plateau.

关 键 词：黄土高原 干旱预报 地理探测器 SPEI 可预报性 

分 类 号：P426.616[天文地球—大气科学及气象学] P456[环境科学与工程—灾害防治] X43