{"title":"A multi-objective comparative framework for Enhanced GRACE-Groundwater comparative analysis","authors":"Mohamed Akl , Brian F. Thomas , Peter J. Clarke","doi":"10.1016/j.jhydrol.2025.134403","DOIUrl":"10.1016/j.jhydrol.2025.134403","url":null,"abstract":"<div><div>Accurate monitoring of groundwater resources is essential for sustainable water management, especially under escalating pressures from climate variability and intensive human activities. Despite significant advancements provided by the Gravity Recovery and Climate Experiment (GRACE) satellites in monitoring terrestrial water storage anomalies (GRACE-TWSA), isolating representative groundwater signals (GRACE-GWA) remains challenging. This is primarily due to uncertainties in complementary water budget components, which are essential for disaggregating GRACE-TWSA. While multi-model approaches to deriving GRACE-GWA can account for these uncertainties, systematic frameworks to objectively compare and constrain multi-model realizations against observed groundwater data remain scarce. To address this gap, we apply a multi-objective comparative framework employing Nash–Sutcliffe Efficiency (NSE) and Kling-Gupta Efficiency (KGE) metrics to compare multi-model GRACE-GWA realizations against in-situ basin-scale groundwater anomalies. Although these metrics are widely used in the hydrologic community, their combined application for GRACE-GWA evaluation is uncommon. Unlike conventional correlation-based approaches, our framework captures critical aspects of time series similarity, including seasonal amplitude fidelity and magnitude consistency, thus enabling clearer identification of optimal groundwater storage realizations. Our findings reveal significant uncertainty between multi-model groundwater storage trend and seasonal amplitude, emphasizing critical limitations often overlooked in standard GRACE-GWA assessments. By systematically isolating the most hydrologically consistent realizations, our framework significantly enhances the reliability, interpretability, and applicability of GRACE-based groundwater estimates. This methodological framework supports more accurate groundwater monitoring, strengthens data-driven decision-making processes, and ultimately contributes toward ensuring the long-term sustainability and resilience of vital groundwater resources.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134403"},"PeriodicalIF":6.3,"publicationDate":"2025-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145311739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cheick Doumbia , Alain N. Rousseau , Michel Baraer , Stephane Savary
{"title":"Assessing climate change impact on glacier runoff in the Upper Yukon Watershed: A Comparative study of CMIP5 and CMIP6 projections","authors":"Cheick Doumbia , Alain N. Rousseau , Michel Baraer , Stephane Savary","doi":"10.1016/j.jhydrol.2025.134398","DOIUrl":"10.1016/j.jhydrol.2025.134398","url":null,"abstract":"<div><div>As climate change continues to drive hydrological shifts, understanding the evolving contributions of glaciers to discharge becomes crucial for effective water resource management. Most previous studies in mountainous regions have relied on models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to analyze future discharge. However, there is a lack of focus on comparing these hydroclimatic assessments with those driven by recent CMIP6 models in these regions. The present study project the future contribution of glaciers to discharge using outputs of CMIP5 and CMIP6 models over the glacierized Upper Yukon Watershed (UYW). First, the glacier model parameters of a semi-distributed hydrological model were calibrated using observed daily discharge over the period 2013–2018. Then, the glacier mass losses from the hydrological model were compared with estimates from elevation changes. Finally, climate change projections of glacier contribution to discharge were performed using ten models based on the Representative Concentration Pathways RCP4.5 and RCP8.5 (CMIP5), and fourteen simulations based on the Shared Socioeconomic Pathways SSP2-4.5 and SSP3-7.0 (CMIP6). The considered temporal horizons were 2011–2040, 2041–2070 and 2071–2100, with 1988–2018 as the reference period. During the calibration period, glacier mass changes from the hydrological model compared well with those from elevation changes, while simulated discharge for the reference period from RCP4.5, RCP8.5, SSP2-4.5 and SSP3-7.0 scenarios closely matched those observed. However, glacier contributions from CMIP6 scenarios over the reference period were more aligned with previous estimates compared to those from the CMIP5 scenarios. Despite a decrease in glacier contributions from CMIP6 scenarios, the long-term annual average volumes of discharge increased over time due to simultaneous increase in temperature and precipitation. These results highlight the consistency of using CMIP6 simulations and demonstrate that decreasing glacier contributions will not affect the annual volume of water in the UYW.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134398"},"PeriodicalIF":6.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145322210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Spatiotemporal disparity of water scarcity risk and sharing responsibility: an integrated framework for urban agglomerations","authors":"Zhiwei Luo , Ling Ji , Yulei Xie","doi":"10.1016/j.jhydrol.2025.134396","DOIUrl":"10.1016/j.jhydrol.2025.134396","url":null,"abstract":"<div><div>Water scarcity increasingly threatens regional economies through cascading supply chain disruptions, making it essential to understand how risks propagate and how responsibilities should be shared. This study develops a water-constrained mixed-MRIO model integrated with responsibility-sharing mechanisms, and applies it to the Beijing-Tianjin-Hebei (BTH) urban agglomeration. Results show that indirect losses can exceed direct losses by over 50% in high-APL sectors, highlighting the amplifying role of network topology beyond water intensity. Scenario analysis reveals contrasting outcomes: targeting high-water-use sectors concentrates direct losses, whereas exempting livelihood-related sectors shifts the burden to manufacturing and construction, leading to extensive downstream spillovers. Across the three responsibility allocation schemes (value-added retention, Ghosh distance-based proximity, and APL-driven propagation), the results consistently reveal a misalignment: upstream Hebei cities absorb disproportionate production-side losses, whereas Beijing and Tianjin retain consumption-side benefits supported by infrastructure and institutional advantages. Robustness checks with substitution, buffering, and structural perturbations confirm that these asymmetries persist across parameter variations. The findings underline that without cross-regional eco-compensation, water rights trading, or differentiated quota systems, current governance perpetuates structural inequities. By linking loss propagation with responsibility allocation, this framework provides actionable diagnostics for balancing competitiveness with hydrological sustainability in urban agglomerations.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134396"},"PeriodicalIF":6.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145264696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shuting Zhao , Yuan Qiu , Zihuang Yan , Lifeng Wu , Rangjian Qiu , Yufeng Luo
{"title":"The potential of AI global weather models for reference evapotranspiration forecasting: a comparison with numerical weather prediction models","authors":"Shuting Zhao , Yuan Qiu , Zihuang Yan , Lifeng Wu , Rangjian Qiu , Yufeng Luo","doi":"10.1016/j.jhydrol.2025.134363","DOIUrl":"10.1016/j.jhydrol.2025.134363","url":null,"abstract":"<div><div>Accurate forecasting of reference crop evapotranspiration (ET<sub>0</sub>) is crucial for optimizing agricultural water use efficiency and mitigating climate impacts on irrigation demand. However, most existing ET<sub>0</sub> forecasting methods struggle to maintain high precision at short-term forecasts. Artificial intelligence (AI)-driven global weather forecast has recently achieved marked success. Nevertheless, the application of AI weather model’s outputs for ET<sub>0</sub> forecasting remains unexplored. Therefore, this study constructed daily ET<sub>0</sub> forecasting models for 1–10 d lead times across 94 stations in mainland China for 2020–2021 using the FAO-56 Penman-Monteith (PM) equation based on AI weather model-GraphCast and two numerical weather prediction datasets − ECMWF and JMA. The performance of these datasets was evaluated across seven climatic zones in mainland China, and we further assessed optimization potential for these forecast datasets using XGBoost. The results of raw forecast outputs indicated that the GraphCast-based PM model outperforms ECMWF and JMA-based across 1–9 d lead times, achieving the highest forecast accuracy at 53.2–77.7 % of stations. To further improve forecast quality, we applied XGBoost post-processing, which significantly enhanced the performance of all three forecasting datasets at 1–10 d lead times, reducing mean RMSE to 0.72–0.99 mm d<sup>-1</sup>, with the most substantial improvement observed for ECMWF at 1 d lead time (31.8 % reduction in RMSE). The GraphCast-based XGBoost model exhibits superior global performance index rankings (79.8–96.8 % of stations) over the GraphCast-based PM model (67.7–77.7 %) at 1–7 d lead times. However, its dominance declined to 28.7–53.2 % of stations at 7–10 d lead times, with JMA surpassing GraphCast performance at 10 d lead time. Therefore, we strongly recommend the GraphCast-XGBoost model for ET<sub>0</sub> forecasting at 1–7 d lead times. This study assesses the potential of AI weather model for ET<sub>0</sub> forecasting in mainland China, unveiling a synergistic optimization pathway with XGBoost, providing irrigation optimization insights for similar regions.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134363"},"PeriodicalIF":6.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145322729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tianyi Chen , Qian Chen , Xinzong Xiao , Xuefeng Guo , Fang Guo , Xinyong Liu , Yitao Lv , Nan Xu , Weiling Sun
{"title":"Construction of a comprehensive water quality assessment framework integrating abiotic indicators, multi-taxonomic biological communities, and machine learning","authors":"Tianyi Chen , Qian Chen , Xinzong Xiao , Xuefeng Guo , Fang Guo , Xinyong Liu , Yitao Lv , Nan Xu , Weiling Sun","doi":"10.1016/j.jhydrol.2025.134380","DOIUrl":"10.1016/j.jhydrol.2025.134380","url":null,"abstract":"<div><div>The global deterioration of rivers and lakes threatens both ecological stability and human health. Current water quality assessments face challenges in indicator selection and weight determination. This study developed a novel water quality index (BE-WQI) framework that integrated environmental indices (physiochemical factors and emerging contaminants) and multi-taxonomic biological communities (bacteria, archaea, eukaryote, alga, benthos, and fish) based on large-scale environmental DNA (eDNA) sequencing. Leveraging a rigorous three-step selection of core abiotic indicators, we employed an advanced gradient-boosting machine learning algorithm (LightGBM) to quantify the feature importance of core indicators in explaining water quality variability, and to generate LightGBM-based weights (W<sub>LGBM</sub>). Following absence filtration, range test, and redundancy test, we examined correlation ranks between selected abiotic indicators and core biological indices, which were derived from alpha diversity, taxonomic abundance, and network structure of biological communities, thereby yielding biological response-based weights (W<sub>Bio</sub>). W<sub>LGBM</sub> and W<sub>Bio</sub>, calculated via the Rank Order Centroid (ROC) method, were integrated through game theory and combined with transformed sub-indices and aggregation functions to construct BE-WQI models. This framework was applied to assess water quality in the eastern route of the South-to-North Water Diversion Project (ER-SNWDP), the world’s largest water transfer project, utilizing our recent monitored eDNA data, 86 physiochemical factors, and 65 emerging contaminants. The BE-WQI classified 46.7% of samples as “slight pollution” and 53.3% as “moderate pollution”, highlighting increased nitrogen pollution downstream and impounded lake impacts. This optimized BE-WQI framework minimized uncertainty and bias in assessment results, providing robust technical support for evaluating water quality.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134380"},"PeriodicalIF":6.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145322187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Storm-induced transformation in wave attenuation by mangroves: Couplings between surges and waves","authors":"Xiufang Qiu , Wen Wei , Wei Chen , Zongyao Chen , Dongfeng Xie , Huayang Cai","doi":"10.1016/j.jhydrol.2025.134389","DOIUrl":"10.1016/j.jhydrol.2025.134389","url":null,"abstract":"<div><div>Coastal regions face growing flood risks due to climate change, and mangroves are increasingly valued for their natural buffering against storm impacts. However, transformation in mangrove-induced wave attenuation under the couplings between storm waves and surges remains unclear. Here, wave attenuation by mangroves under both normal and typhoon conditions (Typhoon PraPiroon, 2024) and the role of surge-wave interactions were examined, based on a 27-day observation of vegetation properties, hydrodynamic conditions and bed-level dynamics across a 30 m wide <em>Kandelia obovata</em> mangrove on Hailing Island, China. The results showed that wave attenuation rate increased by 21 % despite a 58 % decreased in vegetation drag coefficient (<em>C<sub>d</sub></em>) at large Reynolds number (<em>Re</em> > 20000), attributable to typhoon-induced increased in water depth (17 %) and wave height (400 %). A conceptual model was proposed to identify mechanisms underlying the transformed wave attenuation, with the relative contributions of surges and waves quantified through a comparative analysis of idealized simulations for storm-induced changes in water depth, wave height, and vegetation motion. Storm waves contribute to 147 % of the increased wave attenuation, with 274 % from the enhanced incident waves, −42 % from altered vegetation motion and −85 % from their coupling; The contribution rate of surges is −21 %, with another −26 % from surge-wave interactions. When surges and waves interact over a broader range, a threshold where their counteracting effects achieve balance exists and is more sensitive to surges. These findings deepen the understanding of mangrove-induced wave attenuation under high-energy conditions and enlighten the design of mangrove-based coastal defense in storm-prone regions.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134389"},"PeriodicalIF":6.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145322214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Differences in evaporation-precipitation characteristics of a saline porous medium consisting of rods, capillaries, and spheres","authors":"Shivani Chauhan, Navneet Kumar","doi":"10.1016/j.jhydrol.2025.134405","DOIUrl":"10.1016/j.jhydrol.2025.134405","url":null,"abstract":"<div><div>Studies on evaporating saline conventional porous media (CPM) have shown an early transition from Stage 1 to Stage 2 due to salt deposition and complete surface coverage of the top exposed layer. We report an experimental study, utilising three simultaneous diagnostic tools, of evaporation from much simpler rod-based (RBPM) and capillary-based (CBPM) porous media saturated with NaCl-DI water solution under controlled IR heating conditions, and compared these findings to those from CPM experiments. Experiments were conducted with varying rod diameters, initial salt concentrations, and incident heat loads. Both RBPM and CBPM sustained high evaporation rates for a much greater average depth of water level compared to CPM, exhibiting behaviour closer to the ‘No Salt’ cases. However, despite the presence of near-zero radii (NZR) of contacts and corner menisci near the top surface, salt deposition caused pore blockage, leading to an earlier transition compared to the ‘No Salt’ cases, where the transition was driven by water depletion. Among the RBPM cases, the system with the largest rod diameter (5 mm) sustained Stage 1 for the longest duration, likely due to the wider liquid films formed near the NZR of contacts. Interestingly, as with CPM, variations in heat load showed minimal influence on the saturation level at which the transition occurred. Both RBPM and CBPM, as model porous systems, successfully prolonged the Stage 1 duration, while maintaining high evaporation rates. They showed relatively less salt coverage than the CPM cases and hence form suitable candidates for more efficient salt extraction and desalination techniques.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134405"},"PeriodicalIF":6.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145322188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Cabello , M. Escudero-Clares , S. Martos-Rosillo , J.J. Casas , J. Cintas , T. Zakaluk , M.J. Salinas-Bonillo
{"title":"Groundwater-dependent vegetation in semi-arid Mediterranean mountains: The hidden role of weathered hard-rock aquifers","authors":"J. Cabello , M. Escudero-Clares , S. Martos-Rosillo , J.J. Casas , J. Cintas , T. Zakaluk , M.J. Salinas-Bonillo","doi":"10.1016/j.jhydrol.2025.134407","DOIUrl":"10.1016/j.jhydrol.2025.134407","url":null,"abstract":"<div><div>Mountains act as “water towers,” sustaining critical hydrological functions for ecosystems and societies, particularly in arid and semi-arid regions where they provide a disproportionate share of water resources and support unique ecosystems. While their role in storing and releasing surface water is well recognized, groundwater contributions in mountain landscapes remain underexplored. In Mediterranean mountains, where water scarcity and climate-driven changes in precipitation and snowpack dynamics threaten groundwater recharge, this gap is particularly concerning. Here, we identified and mapped potential groundwater-dependent vegetation (pGDV) across contrasting hydrogeological environments in Sierra Nevada (SE Spain) using Sentinel-2 NDVI (2019–2023) ecohydrological indicators: (i) <em>dry-season</em> NDVI, (ii) <em>dry–wet seasonal</em> NDVI difference, and (iii) <em>interannual</em> NDVI variability. We combined these indicators into 64 classes, later simplified into three levels of groundwater dependence (<em>Unlikely</em>, <em>Moderate</em>, and <em>Likely GDV</em>). To explore hydrogeological controls, we assessed spatial patterns across three aquifer zones (alpine, carbonate, and weathered hard-rock) and examined vegetation-climate relationships through correlations with the Standardized Precipitation Evapotranspiration Index (SPEI). Our results reveal the hidden importance of weathered hard-rock aquifers within metamorphic substrates, which, despite limited storage capacity, sustain the largest share of <em>Likely GDV</em> (31.8%), mainly riparian forests, deciduous woodlands, and high-mountain meadows. In comparison, carbonate and alpine aquifers accounted for 14.9% and 1.3% of <em>Likely GDV</em>, respectively. These findings highlight how shallow groundwater in weathered hard-rock aquifers sustains vegetation greenness and functioning during dry periods. Management strategies should prioritize recharge areas and traditional water management systems to preserve groundwater-dependent vegetation under increasing climate stress.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134407"},"PeriodicalIF":6.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145322128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Variability of urban riverine nutrients under coupled human-hydrological-biogeochemical framework","authors":"Ying Zhang, Jianping Gan","doi":"10.1016/j.jhydrol.2025.134406","DOIUrl":"10.1016/j.jhydrol.2025.134406","url":null,"abstract":"<div><div>Nutrient fluxes exhibit complex dynamics under combined influences of land surface processes and human activities. In this study, we comprehensively investigate the long-term variability of riverine nutrient fluxes and uncover the underlying controlling mechanisms in a typical urban agglomeration by integrating observations with the Export Coefficient Model and the Soil and Water Assessment Tool within a coupled human-hydrological-biogeochemical framework. Our results show that the non-point sources (NPS) pollution is controlled by coupled transport processes and nutrient sources. High surface flows in urban and agricultural areas, actively combined with their respective nitrogen deposition and intensive fertilizer use, form active NPS zones. In forested regions, elevated nitrogen levels result from soil nitrate leaching in the lateral layer, where lateral flow is not a limiting factor. The elevated riverine nitrogen flux from NPS, relative to phosphorus, results from the combined effects of abundant nutrient inputs and a disproportionately higher export rate of nitrogen. In contrast, point sources are primarily driven by domestic wastewater, which establishes a persistent core-periphery pollution structure in urban agglomerations, with intensity decreasing from domestic-heavy and hybrid-sourced areas at the core to agro-centric regions at the periphery. However, this structure weakens as domestic sources decline significantly while non-domestic sources remain dynamically balanced. Regarding instream processes, nutrient transformation and removal in channels are positively influenced by organic nutrient ratios and transport distance, whereas upstream influx has a relatively minor impact. These findings provide valuable insights into riverine nutrient pollution from various sources across diverse landscapes in urban agglomerations worldwide.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134406"},"PeriodicalIF":6.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145322176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zengliang Luo , Sihan Zhang , Xiangyi Ding , Lunche Wang , Quanxi Shao , Heqing Huang , Xi Chen , Huan Li
{"title":"A framework for assessing the impact trends of neglecting water surface evaporation and substituting streamflow on water budget closure","authors":"Zengliang Luo , Sihan Zhang , Xiangyi Ding , Lunche Wang , Quanxi Shao , Heqing Huang , Xi Chen , Huan Li","doi":"10.1016/j.jhydrol.2025.134391","DOIUrl":"10.1016/j.jhydrol.2025.134391","url":null,"abstract":"<div><div>Achieving water budget closure using remote sensing datasets remains a major challenge for global hydrological monitoring due to uncertainties in key water budget components, including precipitation (P), evapotranspiration (ET), streamflow (Q), and terrestrial water storage change (TWSC). While various water budget closure correction (BCC) methods have been developed to address imbalances, their effectiveness is often compromised by the neglect of water surface evaporation (WSE) and the substitution of runoff (R) for observed Q. These practices introduce considerable uncertainties. This issue remains insufficiently explored, particularly the impact of different ratios of water surface area to total basin size on total uncertainty, as well as the contribution of substituting R for Q to total uncertainty, under different climates (e.g., in humid and arid watersheds). In this study, we introduce a research framework to assess the impact of substituting R for Q, neglecting WSE, and their combined effects on water budget closure across 62 river basins worldwide. Multiple datasets were used for each budget component, and four widely used BCC methods with varying levels of complexity were employed to enhance the robustness of results: Proportional Redistribution (PR), Constrained Kalman Filter (CKF), Multiple Collocation (MCL), and Minimized Series Deviation (MSD). Our findings reveal that the effects of neglecting WSE are mainly influenced by the ratio of water surface area to land area within each basin. When this ratio exceeded 9.92%, neglecting WSE introduces non-negligible errors. Substituting R for Q has more pronounced effects in humid basins (approximately 11.53%) than in arid basins (around 4.13%). Furthermore, combined uncertainties from both sources are higher than that by a single factor alone in basins with a high proportion of water surface area. These findings provide critical insights into the uncertainties associated with satellite-based water budgeting and offer valuable guidance for improving the reliability of hydrological datasets, particularly in basins lacking direct Q and WSE observations.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"664 ","pages":"Article 134391"},"PeriodicalIF":6.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145322179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}