Journal of Hydrology最新文献

{"title":"Constraining binary alpine karst spring recharge using Ensemble Rainfall-Runoff analysis (ERRA) and artificial tracer tests","authors":"Jasper F.D. Lammers, Martin Masten, Thomas Wagner, Ralf Benischke, Simon Seelig, Wolfgang Schöner, Gerfried Winkler","doi":"10.1016/j.jhydrol.2026.136703","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136703","url":null,"abstract":"Karst systems sustain a substantial share of global freshwater supply, yet their internal discharge dynamics are difficult to characterize because conduit networks are often inaccessible to direct observation. Fluorescent tracer tests can quantify recharge-area-to-spring connections and travel times, but only under the conditions at the time of testing. Rainfall-runoff deconvolution methods such as Ensemble Rainfall-Runoff Analysis (ERRA) offer a complementary, data-driven approach resolving nonlinear, non-stationary discharge responses across catchment wetness and precipitation intensity. We apply ERRA alongside 14 years of tracer test data to the binary Etzbach karst spring (Austrian Alps) to quantify discharge response across antecedent wetness and precipitation intensity conditions, determine whether contributing subcatchments share governing controls, and test consistency between ERRA-derived dynamics and tracer-constrained transit times.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"20 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374185","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":"A realistic spatiotemporally variable rainfall event generator for flood catastrophe modeling","authors":"Yuran Li, Jian He, Lun Dai, Yunhong Lv, Yuanen Pang, Limin Zhang","doi":"10.1016/j.jhydrol.2026.136786","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136786","url":null,"abstract":"Catastrophe modeling, which simulates regional hazard scenarios and losses under extreme events, has become an important tool for flood risk management. Observations of extremes are inherently scarce because such events are rare, making it essential to augment the historical record with synthetic rainfall events that are realistic and spatiotemporally variable. Current probabilistic rainfall models primarily focus on either single-station analysis or the spatial dependence of rainfall metrics (e.g., cumulative rainfall). However, these approaches often fail to capture the dynamic spatiotemporal characteristics of short-duration extreme rainfall events, which are the primary drivers of urban flooding. In this study, we propose a novel spatiotemporal stochastic rainfall generator to simulate rainfall sequences at multiple stations while preserving spatial correlation, as well as realistic hourly temporal variability and correlation. The generator is applied to and calibrated in Hong Kong, a densely urbanized and flood-prone coastal city, using hourly in-situ observations from 141 stations during 1984–2017. Despite operating at hourly resolution, the generator reproduces rainfall statistics consistently across accumulation durations of 1–24 h. It reproduces the main statistical characteristics of historical rainfall, with Nash–Sutcliffe efficiency values of 0.836–0.986 for accumulation durations of 4–72 h. It also captures the spatial patterns of extremes, with a Pearson correlation of 0.806. Hydrodynamic simulations further demonstrate that the realistic temporal variability produced by the generator leads to average flood depth differences of 18.1% and 25.8% compared with the simplified exponential and constant hyetograph scenarios, respectively. These results highlight the importance of representing realistic short-term rainfall variability in stochastic rainfall models for reliable catastrophe modeling.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"18 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374183","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":"Changes in drought transition dynamics under future climate in Great Britain: A Markov chain analysis using SPI and SSI","authors":"Nishant Gaur, Encarni Medina-Lopez, Lindsay Beevers","doi":"10.1016/j.jhydrol.2026.136736","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136736","url":null,"abstract":"Drought in Great Britain (GB) has received increasing attention following recent events, including those of 2018–2019 and 2022. Previous studies based on UKCP18 climate projections and the enhanced Future Flows and Groundwater dataset (eFLaG) have reported increasing drought frequency, duration, and severity across much of GB. However, these conventional drought characteristics do not fully describe how drought states evolve over time. This study addresses that gap by quantifying projected changes in drought transition dynamics across 133 parent catchments in GB using the Standardised Precipitation Index (SPI) and Standardised Streamflow Index (SSI). Drought frequency and severity were evaluated for baseline, near-future, and far-future periods. First-order Markov chain transition matrices were constructed for meteorological and hydrological drought states and compared between baseline and future periods using a non-parametric permutation test. The matrices were then decomposed into downward mobility, upward mobility, dry-to-dry persistence, and wet-to-wet persistence metrics. Results reveal a clear south-east to north-west contrast in future drought transition behaviour. Southern and south-eastern catchments show stronger increases in downward mobility and dry-state persistence, indicating a greater tendency towards drying and weaker recovery towards wetter states. In contrast, north-western catchments show more heterogeneous responses, including simultaneous increases in dry-to-dry and wet-to-wet persistence. Directional change and persistence do not peak in the same regions, indicating that future drought intensification may arise through different transition mechanisms across GB. These findings provide a process-based perspective on future drought evolution, with implications for drought-risk assessment and long-term water management.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"102 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374184","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":"N-tuple collocation for reference-free uncertainty estimation from multi-source hydrological data: beyond triple collocation and three-cornered hat","authors":"Hung T. Pham, Seokhyeon Kim","doi":"10.1016/j.jhydrol.2026.136749","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136749","url":null,"abstract":"Reference-free uncertainty estimation is needed when multiple hydrological datasets are available but reliable ground truth is sparse, scale-mismatched, or absent. Existing approaches, including triple collocation (TC) and the three-cornered hat method (TCH), are limited by fixed triplet requirements, negative error-variance failures, or sensitivity to multiplicative scaling. We introduce N-tuple collocation (NC), a reference-free framework that estimates residual error covariance from three or more collocated datasets by decomposing the observation covariance into a rank-one signal component and a residual covariance term while constraining error variances to remain non-negative and enforcing residual covariance feasibility. In covariance experiments, the box-constrained NC stage produced no negative-variance failures across the tested error-correlation and scaling conditions, remained weakly sensitive to signal-to-noise ratio, became more stable as the number of datasets increased, and improved with longer records. Additional seasonal experiments supported feasibility of the final estimator, with condition-dependent accuracy. We demonstrated NC in a global soil moisture application using ASCAT, SMAP, LPRM, and ERA5-Land products for 2020–2024, with held-out 2023–2024 validation against International Soil Moisture Network observations. In the three-product ASCAT–SMAP–ERA5 experiment, NC increased the valid-pixel domain relative to TC and TCH, with small favorable differences in paired validation comparisons and uncertainty in others. In the four-product ASCAT–SMAP–LPRM–ERA5 experiment, NC remained applicable beyond the classical TC setting and provided broader feasible coverage than TCH. These results indicate that NC provides a scalable, variance-admissible framework for reference-free uncertainty estimation from multi-source hydrological data, with soil moisture merging serving as a global demonstration of its utility in reference-limited settings.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"7 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374213","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":"Spatial and temporal variability in model parameters governing groundwater flood-potential","authors":"Beatrice Richieri, Pablo Merchán-Rivera, Gabriele Chiogna","doi":"10.1016/j.jhydrol.2026.136750","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136750","url":null,"abstract":"Groundwater flooding poses a hazard in shallow aquifers, yet predicting its spatial occurrence is highly challenged by parameter uncertainty and the limited availability of observation points. Using a distributed MODFLOW-NWT model of a shallow alluvial aquifer in Garching (Germany), we performed Morriś global screening and ranking sensitivity analyses on 20 uncertain parameters, including zonally parameterized hydraulic conductivity and specific yield, across three hydrologic periods. We compared how four monitoring configurations influence parameter-sensitivity patterns using a head-based objective function and mapped spatially distributed sensitivities of cell-wise shallow-groundwater responses using a threshold-exceedance metric. The seven most influential parameters were integrated into a Bayesian framework (DREAM) to quantify uncertainty and generate probability maps of shallow groundwater conditions based on both instantaneous threshold exceedance and event duration. Results showed that parameter sensitivities depend strongly on the local hydrological processes represented by the monitoring configurations; for instance, the normalized <mml:math altimg=\"si1.svg\"><mml:msubsup><mml:mover accent=\"true\"><mml:mi>μ</mml:mi><mml:mo stretchy=\"true\">^</mml:mo></mml:mover><mml:mrow><mml:mi>k</mml:mi></mml:mrow><mml:mrow><mml:mo>∗</mml:mo></mml:mrow></mml:msubsup></mml:math> of the Mühlbach riverbed conductance decreases from 19.90% for monitoring points located close to the channel to 11.29% for monitoring points located farther away. Spatial sensitivity mapping revealed pronounced heterogeneity, with hydraulic conductivity and riverbed conductance among the dominant parameters and maximum normalized sensitivities locally exceeding 50%. Posterior uncertainty of the effective zonal parameters reflected the spatial distribution of the monitoring network, with hydrogeological zones well represented by monitoring observations exhibiting better-constrained parameter estimates, while poorly monitored zones remained more weakly constrained and represent priorities for future network expansion. This integrated framework demonstrates how monitoring data can be leveraged to generate uncertainty-aware, probabilistic estimates of shallow groundwater conditions and groundwater-flood potential, accounting for both event probability and persistence.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"21 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374284","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":"Hydrodynamic evolution and erosion dynamics in dispersive soil slopes under repeated rainfall","authors":"Xingyao Li, Henghui Fan, Jinghao Xu, Haoran Zhang","doi":"10.1016/j.jhydrol.2026.136740","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136740","url":null,"abstract":"The complicated coupling between soil dispersivity and erosion dynamics remains a blind spot in understanding slope erosion processes, particularly under cumulative rainfall events. This study investigated hydrodynamic behaviors and soil erosion rate responses of slopes with varying dispersivity under five consecutive rainfall events. Indoor simulated rainfall experiments were conducted in a soil flume (2.0 m × 1.0 m × 0.4 m) under a constant rainfall intensity of 60 mm·h<ce:sup loc=\"post\">−1</ce:sup>, with five consecutive 40-min rainfall events separated by 48-h intervals, using Na<ce:inf loc=\"post\">2</ce:inf>CO<ce:inf loc=\"post\">3</ce:inf>-amended loess with Na<ce:inf loc=\"post\">2</ce:inf>CO<ce:inf loc=\"post\">3</ce:inf> contents ranging from 0% to 0.20% under controlled laboratory conditions to regulate soil dispersivity levels from non-dispersive to dispersive. Results showed that soil dispersivity fundamentally altered the hydrodynamic characteristics. Flow velocity (<ce:italic>V</ce:italic>), Reynolds number (<ce:italic>Re</ce:italic>), Froude number (<ce:italic>Fr</ce:italic>), and stream power (<ce:italic>ω</ce:italic>) measured during the initial rainfall increased significantly with higher dispersivity, while the Darcy–Weisbach friction factor (<ce:italic>f</ce:italic>) decreased. Higher soil dispersivity promoted the evolution of flow conditions toward a supercritical regime. Soil dispersivity profoundly altered erosion patterns. Dispersive soils exhibited a slope-wide, early-onset erosion pattern, with soil erosion peaking during R1-R2. In contrast, non-dispersive soils displayed a toe-localized, delayed-onset erosion pattern, with major erosion occurring during R4-R5. The empirical Horton model (<ce:italic>R</ce:italic><ce:sup loc=\"post\">2</ce:sup> = 0.80) and the non-linear erosion model (<ce:italic>R</ce:italic><ce:sup loc=\"post\">2</ce:sup> = 0.88), both incorporating soil dispersivity, were developed. ANOVA confirmed that soil dispersivity was the primary factor controlling runoff (66.60%) and soil erosion (64.83%) variations. Early slope-wide modification is proposed for dispersive slopes, while terminal energy dissipation at the toe is recommended for non-dispersive slopes.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"14 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374232","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":"Scale-dependent phosphorus export across rainfall gradients: Hydrological dynamics and storm-event responses","authors":"Xinyu Liu, Quan Liu, Tao Wang, Minghua Zhou, Bo Zhu","doi":"10.1016/j.jhydrol.2026.136706","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136706","url":null,"abstract":"Effective control of watershed non-point source phosphorus (P) pollution is often hindered by a lack of understanding of episodic, high-magnitude export events. Specifically, the critical rainfall thresholds triggering these events and their modulation by catchment scale remain unclear. Here, this study investigated P export dynamics across four nested catchments (3.2–1236.4 ha) in the Sichuan Basin of China, employing high-frequency automated sampling across a rainfall gradient. Results identified a critical rainfall threshold of approximately 30 mm. Below this threshold, TP export remained low, with a higher relative contribution of dissolved total P (DTP) during moderate events. Above the threshold, P loads increased sharply and PP was the dominant exported fraction. At Wan’an (WA), the largest catchment, four monitored events contributed 51.1 % and 59.2 % of annual composite TP and PP loads, respectively. PP accounted for 95.6 % of TP at WA during the largest event. This threshold response was strongly scale-dependent, with small headwater catchments exhibiting source-limited, flashy responses (first flush), whereas larger catchments showed buffered hydrographs attributed to network attenuation. Furthermore, PO<ce:inf loc=\"post\">4</ce:inf>-P/DTP ratios were higher in the larger catchments than in SR, indicating scale-dependent differences in dissolved P speciation. These findings suggest a paradigm shift in management strategies away from static annual load reduction towards targeted controls in critical source areas during high-risk storm events identified by specific rainfall thresholds.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"20 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374268","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":"Disentangling the impacts of climate change and human activities on hydrological drought recovery from a daily grid-scale perspective","authors":"Yifan Pan, Tao Peng, Vijay P. Singh, Ji Liu, Qingxia Lin, Xiaohua Dong, Jiali Guo, Chao Song, Dan Yu, Gaoxu Wang","doi":"10.1016/j.jhydrol.2026.136734","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136734","url":null,"abstract":"Understanding hydrological drought recovery is crucial for sustainable water resources management and ecological restoration in a changing environment. However, assessments of the spatiotemporal patterns of hydrological drought recovery and its driving factors from a comprehensive and causal perspective remain limited. In this study, we applied the grid-based PCR-GLOBWB 2.0 model to reconstruct daily-scale gridded streamflow in the Hanjiang River basin (HRB), China, under both natural and anthropogenic-affected scenarios. Hydrological drought events were identified at the grid scale using the Standardized Streamflow Index (SSI), and their spatiotemporal variation patterns were analyzed. A scenario comparison approach was employed to evaluate the relative contribution rates of climate change and different human activities to changes in hydrological drought recovery. Results showed climate change prolonged recovery time (RT) across the entire HRB with a relative contribution rate of 333.4%, reflecting the offsetting effect of opposite-sign human contributions, while reducing drought resilience (Res) and instantaneous recovery speed (IRS), with relative contribution rates of 79.0% and 74.8%, respectively. Reservoir regulation and water withdrawals also increased RT, with relative contribution rates of −38.6% and −185.1%, respectively, and decreased Res and IRS, with contribution rates ranging from 15.9% to 12.6% and 10.3% to 9.6%. Although climate change exerted a greater impact on hydrological drought recovery at the basin-wide scale, human activities played a more dominant role in most sub-basins. These findings provide valuable insights into the driving mechanisms of hydrological drought recovery and inform water resource management strategies under changing environmental conditions, highlighting the importance of disentangling climate and anthropogenic drivers for targeted adaptation.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"7 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374267","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":"Investigating the spatial patterns in the dependence of daily rainfall depth on wet spell duration over Europe","authors":"Carmelo Cammalleri, Eren Senyuz, Carmelo Agnese, Giorgio Baiamonte, Stefano Ferraris, Tommaso Martini","doi":"10.1016/j.jhydrol.2026.136732","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136732","url":null,"abstract":"Daily rainfall amount and occurrence are often investigated separately, without accounting for the possible dependence of rainfall depth (<ce:italic>h</ce:italic>) on wet spell duration (<ce:italic>ws</ce:italic>). Here, we show that this dependence occurs across Europe and exhibits consistent spatial patterns. The approach adopted for modelling this dependence relies on a log-growth relationship between <ce:italic>ws</ce:italic> and normalized arithmetic (AM) and geometric (GM) means. Applications of this model at European scale using E-OBS daily gridded data between 1981 and 2020 closely reproduce the empirical conditional means, with mean absolute differences below 1 mm and relative differences smaller than 10%. By assuming that daily rainfall depths follow a Polylog distribution, the full domain of <ce:italic>h|ws</ce:italic> dependence is captured by only four parameters (AM, GM, and the two parameters of the log-growth function). A spatial cluster analysis of these parameters highlights three major regimes: “strong” dependence in the Mediterranean and the western coast of Europe, “weak” dependence over most of eastern Europe, and a transition “intermediate” dependence region in the middle. Decision tree and random forest models reproduce the broad spatial patterns of these three regions using a limited number of predictors: elevation, mean annual temperature, and frequency of wet days. This result highlights those regions were neglecting the <ce:italic>h</ce:italic>|<ce:italic>ws</ce:italic> dependence may lead to substantial differences (even larger than 10 mm on the 90-th quantile), but also suggests how the dependence patterns can be systematically associated with coherent hydroclimatic gradients, which reflect common rainfall-generating mechanisms, such as orographic effects, and may also be linked to large-scale teleconnection patterns.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"14 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374269","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":"The influence of planning horizon on the importance of streamflow parameter uncertainty in reservoir analyses","authors":"Natasha Ballis, Rory Nathan, Murray Peel, Benjamin J. Henley, Thomas McMahon","doi":"10.1016/j.jhydrol.2026.136731","DOIUrl":"https://doi.org/10.1016/j.jhydrol.2026.136731","url":null,"abstract":"Longer streamflow records allow us to calculate streamflow model parameters with greater certainty. There is a common assumption that this reduction in parameter uncertainty is of practical benefit to the design and operation of water resource systems. Here we explore this assumption by considering the uncertainty in estimates of reservoir reliability based on streamflow records of different lengths. We consider stationary first-order autoregressive synthetic streamflows with example annual variabilities, skewnesses and autocorrelations reflective of a broad range of hydrological regimes in reservoir behavior analyses. We also consider a range of reservoir planning horizons. We find that the reduced parameter uncertainty gained from a longer record (<ce:math altimg=\"si42.svg\"></ce:math> 30 years) translates into appreciably more certain reliability estimates only when planning horizons are sufficiently long, in the order of 100 years or more. For shorter planning horizons, in the order of 10–30 years, reduced parameter uncertainty has little impact on estimates of reliability. Rather, these analyses are dominated by aleatory uncertainty. Therefore, we suggest that for the design and operation of water resource systems under the assumption of a stationary climate, the practical benefit of reduced parameter uncertainty gained from longer records depends on the length of the reservoir planning horizon.","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"99 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149374295","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}