[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-detail-123579-en":3,"doc-seo-123579-105":30,"detail-sidebar-cat-0-en-105":91},{"code":4,"msg":5,"data":6},0,"success",{"doc_id":7,"user_id":8,"nickname":9,"user_avatar":10,"doc_module":4,"category_id":11,"category_name":12,"doc_title":13,"doc_description":14,"doc_content":15,"file_id":16,"file_url":17,"file_type":18,"file_size":19,"view_count":4,"is_deleted":4,"is_public":20,"is_downloadable":20,"audit_status":20,"page_count":21,"language":22,"language_code":23,"site_id":24,"html_lang":23,"table_of_contents":25,"faqs":26,"seo_title":27,"seo_description":14,"update_tm":28,"read_time":29},123579,1099513958607,"Jiven","https://ap-avatar.wpscdn.com/avatar/100002390cf8733938c?x-image-process=image/resize,m_fixed,w_180,h_180&k=1778829742770036399",8,"Research & Report","Estimating propagation probability from meteorological to ecological droughts using a hybrid machine learning copula method","The study addresses drought impacts on vegetation as a transition of water shortage from meteorological to ecological stages, emphasizing why understanding drought propagation mechanisms matters for ecological conservation. A probability framework is built to quantify how meteorological drought triggers ecological drought at varying magnitudes across northwestern China. Using 1982–2020 events, it identifies meteorological and ecological droughts via a three-dimensional method, extracts propagated events through a spatiotemporal overlap rule, and estimates propagation probability by coupling machine learning with a C-vine copula.","Hydrol. Earth Syst. Sci., 27, 559–576, 2023 [https://doi.org/10.5194/hess-27-559-2023](https://doi.org/10.5194/hess-27-559-2023)[ ](https://doi.org/10.5194/hess-27-559-2023)© Author(s) 2023 . This work is distributed under the Creative Commons Attribution 4 .0 License.  \nEstimating propagation probability from meteorological to  \necological droughts using a hybrid machine learning copula method  \nTianliang Jiang 1,2 , Xiaoling Su 1,2 , Gengxi Zhang3 , Te Zhang 1,2 , and Haijiang Wu 1,2  \n1 College of Water Resources and Architectural Engineering, Northwest A & F University, Yangling, Shaanxi 712100, China  \n2 Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Northwest A & F University, Yangling, Shaanxi 712100, China  \n3 College of Hydraulic Science and Engineering, Yangzhou University, Yangzhou 225009, China Correspondence: Xiaoling Su ([xiaolingsu@nwafu.edu.cn](xiaolingsu@nwafu.edu.cn))  \nReceived: 23 February 2022 – Discussion started: 1 April 2022  \nRevised: 18 December 2022 – Accepted: 11 January 2023 – Published: 27 January 2023  \nAbstract. The impact of droughts on vegetation is essentially manifested as the transition of water shortage from the meteorological to ecological stages. Therefore, understanding the mechanism of drought propagation from meteorological to ecological drought is crucial for ecological conservation. This study proposes a method for calculating the probability of meteorological drought to trigger ecological drought at different magnitudes in northwestern China. In this approach, meteorological and ecological drought events during 1982–2020 are identified using the three-dimensional identification method; the propagated drought events are extracted according to a certain spatiotemporal overlap rule, and propagation probability is calculated by coupling the machine learning model and C-vine copula. The results indicate that (1) 46 drought events are successfully paired with 130 meteorological and 184 ecological drought events during 1982–2020, and ecological drought exhibits a longer duration but smaller affected area and severity than meteorological drought; (2) a quadratic discriminant analysis (QDA) classifier performs the best among the 11 commonly used machine learning models which are combined with fourdimensional C-vine copula to construct the drought propagation probability model; and (3) the hybrid method considers more drought characteristics and a more detailed propagation process which addresses the limited applicability of the traditional method to regions with large spatial extent.  \n1 Introduction  \nDrought is a multivariable and complex natural hazard with the characteristics of slow evolution, wide impact, and spatial extent (Feng et al., 2021; Wu et al., 2021; Zhang et al., 2021a, b) . Conventionally, drought can be classified into meteorological drought, hydrological drought, agricultural drought, and socioeconomic drought. It is commonly accepted that all types of drought originate from meteorological drought (Mishra and Singh, 2010) . Crausbay et al. (2017) argued that existing drought types are described through a “humancentric” lens to characterize a range of effects generated by meteorological drought. This implies that the response of the ecosystem to drought is generally ignored in policy development, which in turn elicits water use conflicts between humans and ecosystems (J. Zhang et al., 2021) . The Ecological Drought working group of Science for Nature and People Partnership (SNAPP) proposed a framework of ecological drought from an “ecology-centric” lens, which incorporates ecological, meteorological, and hydrological information (Crausbay et al., 2017) . Ecological drought was thus defined as an episodic deficit in water availability that drives ecosystems beyond thresholds of resilience into a vulnerable state, impacts ecosystem services, and triggers feedback in natural and/or human systems (Bradford et al., 2020; Crausbay et al., 2017; M","cbCaitmEqSCPD6dW","https://ap.wps.com/l/cbCaitmEqSCPD6dW","pdf",7805773,1,18,"English","en",105,"# Introduction\n## Drought types and ecological drought concepts\n## Vegetation response and drought propagation rationale\n## Approaches to drought propagation analysis","[{\"question\":\"Why is drought propagation from meteorological to ecological drought important?\",\"answer\":\"Vegetation impacts reflect the shift of water shortage from meteorological to ecological stages. Understanding this mechanism supports ecological conservation and improved drought monitoring.\"},{\"question\":\"How are meteorological and ecological drought events identified in the study?\",\"answer\":\"Events from 1982–2020 are identified using a three-dimensional identification method for both meteorological and ecological droughts.\"},{\"question\":\"How is propagation probability estimated from meteorological to ecological drought?\",\"answer\":\"Propagated drought events are extracted using a spatiotemporal overlap rule, then propagation probability is computed by coupling a machine learning model with a C-vine copula.\"}]","Estimating propagation probability from meteorological to ecological droughts using a hybrid machine learning copula method | PDF",1785817441,45,{"code":4,"msg":31,"data":32},"ok",{"site_id":24,"language":23,"slug":33,"title":13,"keywords":34,"description":14,"schema_data":35,"social_meta":86,"head_meta":88,"extra_data":90,"updated_unix":28},"estimating-propagation-probability-from-meteorological-to-ecological-droughts-using-a-hybrid-machine-learning-copula-method","",{"@graph":36,"@context":85},[37,54,68],{"@type":38,"itemListElement":39},"BreadcrumbList",[40,44,48,51],{"item":41,"name":42,"@type":43,"position":20},"https://docshare.wps.com","Home","ListItem",{"item":45,"name":46,"@type":43,"position":47},"https://docshare.wps.com/document/","Document",2,{"item":49,"name":12,"@type":43,"position":50},"https://docshare.wps.com/document/research-report/",3,{"item":52,"name":13,"@type":43,"position":53},"https://docshare.wps.com/document/estimating-propagation-probability-from-meteorological-to-ecological-droughts-using-a-hybrid-machine-learning-copula-method/123579/",4,{"url":52,"name":13,"@type":55,"author":56,"headline":13,"publisher":58,"fileFormat":61,"inLanguage":23,"description":14,"dateModified":62,"datePublished":62,"encodingFormat":61,"isAccessibleForFree":63,"interactionStatistic":64},"DigitalDocument",{"name":9,"@type":57},"Person",{"url":41,"name":59,"@type":60},"DocShare","Organization","application/pdf","2026-08-04",true,{"@type":65,"interactionType":66,"userInteractionCount":4},"InteractionCounter",{"@type":67},"ViewAction",{"@type":69,"mainEntity":70},"FAQPage",[71,77,81],{"name":72,"@type":73,"acceptedAnswer":74},"Why is drought propagation from meteorological to ecological drought important?","Question",{"text":75,"@type":76},"Vegetation impacts reflect the shift of water shortage from meteorological to ecological stages. Understanding this mechanism supports ecological conservation and improved drought monitoring.","Answer",{"name":78,"@type":73,"acceptedAnswer":79},"How are meteorological and ecological drought events identified in the study?",{"text":80,"@type":76},"Events from 1982–2020 are identified using a three-dimensional identification method for both meteorological and ecological droughts.",{"name":82,"@type":73,"acceptedAnswer":83},"How is propagation probability estimated from meteorological to ecological drought?",{"text":84,"@type":76},"Propagated drought events are extracted using a spatiotemporal overlap rule, then propagation probability is computed by coupling a machine learning model with a C-vine copula.","https://schema.org",{"og:url":52,"og:type":87,"og:title":13,"og:site_name":59,"og:description":14},"article",{"robots":89,"canonical":52},"index,follow",{"doc_id":7,"site_id":24},{"code":4,"msg":5,"data":92},[93,97,101,105,110,115,120,123,128,131,135],{"id":20,"doc_module":4,"doc_module_name":46,"category_name":94,"show_sort_weight":95,"slug":96},"Story & Novel",90,"story-novel",{"id":47,"doc_module":4,"doc_module_name":46,"category_name":98,"show_sort_weight":99,"slug":100},"Literature",80,"literature",{"id":53,"doc_module":4,"doc_module_name":46,"category_name":102,"show_sort_weight":103,"slug":104},"Exam",70,"exam",{"id":106,"doc_module":4,"doc_module_name":46,"category_name":107,"show_sort_weight":108,"slug":109},5,"Comic",60,"comic",{"id":111,"doc_module":4,"doc_module_name":46,"category_name":112,"show_sort_weight":113,"slug":114},6,"Technology",50,"technology",{"id":116,"doc_module":4,"doc_module_name":46,"category_name":117,"show_sort_weight":118,"slug":119},7,"Healthcare",40,"healthcare",{"id":11,"doc_module":4,"doc_module_name":46,"category_name":12,"show_sort_weight":121,"slug":122},30,"research-report",{"id":124,"doc_module":4,"doc_module_name":46,"category_name":125,"show_sort_weight":126,"slug":127},9,"Religion & Spirituality",20,"religion-spirituality",{"id":126,"doc_module":4,"doc_module_name":46,"category_name":129,"show_sort_weight":126,"slug":130},"World Cup","world-cup",{"id":132,"doc_module":4,"doc_module_name":46,"category_name":133,"show_sort_weight":132,"slug":134},10,"Lifestyle","lifestyle",{"id":136,"doc_module":4,"doc_module_name":46,"category_name":137,"show_sort_weight":106,"slug":138},19,"General","general"]