An integrated framework for non-stationary hydrological drought assessment using time-varying parameter standardized streamflow index and time-varying threshold level method

IF 4.7 2区地球科学 Q1 WATER RESOURCES

Journal of Hydrology-Regional Studies Pub Date : 2025-03-21 DOI:10.1016/j.ejrh.2025.102329

Menghao Wang , Shanhu Jiang , Liliang Ren , Junzeng Xu , Shanshui Yuan , Chong-Yu Xu

{"title":"An integrated framework for non-stationary hydrological drought assessment using time-varying parameter standardized streamflow index and time-varying threshold level method","authors":"Menghao Wang , Shanhu Jiang , Liliang Ren , Junzeng Xu , Shanshui Yuan , Chong-Yu Xu","doi":"10.1016/j.ejrh.2025.102329","DOIUrl":null,"url":null,"abstract":"<div><h3>Study region</h3><div>Weihe River basin (WRB) in northern China.</div></div><div><h3>Study focus</h3><div>In a changing environment, traditional drought assessment methods may not be applicable when assumptions of stationarity are violated. Accordingly, this study proposes a framework that incorporates the time-varying parameter standardized streamflow index (SSI<sub>var</sub>) and threshold level method (TL<sub>var</sub>) for the non-stationary hydrological drought assessment. Then, the SSI<sub>var</sub> and TL<sub>var</sub> methods are compared with time-invariant and transplantation parameter SSI (SSI<sub>invar</sub> and SSI<sub>tran</sub>) and TL (TL<sub>invar</sub> and TL<sub>tran</sub>) to validate their effectiveness.</div></div><div><h3>New hydrological insights for the region</h3><div>Validation results showed that SSI<sub>var</sub> has the highest Kendall correlation coefficients with standardized precipitation index (SPI) and soil moisture index (SSMI) at 0.81 and 0.78, respectively, outperforming SSI<sub>invar</sub> (0.67and 0.62) and SSI<sub>tran</sub> (0.68 and 0.63). The TL<sub>var</sub> method behaves in the same way, indicating that the SSI<sub>var</sub> and TL<sub>var</sub> methods provide a more accurate assessment of non-stationary hydrological drought. Furthermore, the comparison results show that the mean duration and severity of hydrological drought in the WRB increased by 22.37 % and 13.72 % for SSI<sub>var</sub> method and 34.69 % and 19.15 % for TL<sub>var</sub> method from 1961–1990 to 1991–2020, respectively, revealing that hydrological drought in the WRB has aggravated over the past 30 years. Overall, the combined use of SSI<sub>var</sub> and TL<sub>var</sub> provides a comprehensive understanding of non-stationary drought, integrating qualitative (e.g., severity levels) and quantitative (e.g., streamflow deficits) measures.</div></div>","PeriodicalId":48620,"journal":{"name":"Journal of Hydrology-Regional Studies","volume":"59 ","pages":"Article 102329"},"PeriodicalIF":4.7000,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Hydrology-Regional Studies","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2214581825001533","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"WATER RESOURCES","Score":null,"Total":0}

引用次数: 0

Abstract

Study region

Weihe River basin (WRB) in northern China.

Study focus

In a changing environment, traditional drought assessment methods may not be applicable when assumptions of stationarity are violated. Accordingly, this study proposes a framework that incorporates the time-varying parameter standardized streamflow index (SSI_var) and threshold level method (TL_var) for the non-stationary hydrological drought assessment. Then, the SSI_var and TL_var methods are compared with time-invariant and transplantation parameter SSI (SSI_invar and SSI_tran) and TL (TL_invar and TL_tran) to validate their effectiveness.

New hydrological insights for the region

Validation results showed that SSI_var has the highest Kendall correlation coefficients with standardized precipitation index (SPI) and soil moisture index (SSMI) at 0.81 and 0.78, respectively, outperforming SSI_invar (0.67and 0.62) and SSI_tran (0.68 and 0.63). The TL_var method behaves in the same way, indicating that the SSI_var and TL_var methods provide a more accurate assessment of non-stationary hydrological drought. Furthermore, the comparison results show that the mean duration and severity of hydrological drought in the WRB increased by 22.37 % and 13.72 % for SSI_var method and 34.69 % and 19.15 % for TL_var method from 1961–1990 to 1991–2020, respectively, revealing that hydrological drought in the WRB has aggravated over the past 30 years. Overall, the combined use of SSI_var and TL_var provides a comprehensive understanding of non-stationary drought, integrating qualitative (e.g., severity levels) and quantitative (e.g., streamflow deficits) measures.

查看原文本刊更多论文

求助全文

约1分钟内获得全文求助全文

来源期刊

Journal of Hydrology-Regional Studies Earth and Planetary Sciences-Earth and Planetary Sciences (miscellaneous)

CiteScore

6.70

自引率

8.50%

发文量

284

审稿时长

60 days

期刊介绍： Journal of Hydrology: Regional Studies publishes original research papers enhancing the science of hydrology and aiming at region-specific problems, past and future conditions, analysis, review and solutions. The journal particularly welcomes research papers that deliver new insights into region-specific hydrological processes and responses to changing conditions, as well as contributions that incorporate interdisciplinarity and translational science.