There is a global abundance of non-perennial rivers and streams, of which are predicted to increase due to environmental change and anthropogenic influences. However, most modeled representations of streamflow have been constructed with perennial systems in mind, leaving a gap in our understanding and representation of non-perennial systems. To adapt to future challenges, there is a need to determine what modeled representations of low- and no-flow in non-perennial rivers and streams do well and where uncertainties may lie in the internal representations of hydrologic processes. Here we compare four publicly available process-based hydrologic models: Variable Infiltration Capacity, Precipitation Runoff Modeling System, and National Water Model versions 2.1 and 3.0, in their ability to represent non-perennial streamflow regimes across 156 streamgages that experience non-perennial streamflow behavior in the Pacific Northwest. Our results show that process-based models are largely unable to capture non-perennial streamflow behavior, and that simulation skill decreases as a function of increasing aridity of a streamgage location. Most simulations underestimate the number of no- and low-flow days a streamgage experiences and overestimates the magnitude of low-flows. The ability to accurately model non-perennial systems is paramount to draw inferences about the connections between hydrologic characteristics of low- and no-flow and the potential ecological, biogeochemical, and societal implications of these important systems. Our findings suggest that improving our predictive understanding of non-perennial streamflow of rivers and streams within the Pacific Northwest will fill critical gaps and better target the timing and location of future research, management, and conservation efforts as well as improve the usability of these models for a wider audience of practitioners across fields.
{"title":"Process-Based Hydrologic Model Representations of Non-Perennial Streamflow in the Pacific Northwest, USA","authors":"Adam N. Price, Kendra E. Kaiser","doi":"10.1029/2025wr040626","DOIUrl":"https://doi.org/10.1029/2025wr040626","url":null,"abstract":"There is a global abundance of non-perennial rivers and streams, of which are predicted to increase due to environmental change and anthropogenic influences. However, most modeled representations of streamflow have been constructed with perennial systems in mind, leaving a gap in our understanding and representation of non-perennial systems. To adapt to future challenges, there is a need to determine what modeled representations of low- and no-flow in non-perennial rivers and streams do well and where uncertainties may lie in the internal representations of hydrologic processes. Here we compare four publicly available process-based hydrologic models: Variable Infiltration Capacity, Precipitation Runoff Modeling System, and National Water Model versions 2.1 and 3.0, in their ability to represent non-perennial streamflow regimes across 156 streamgages that experience non-perennial streamflow behavior in the Pacific Northwest. Our results show that process-based models are largely unable to capture non-perennial streamflow behavior, and that simulation skill decreases as a function of increasing aridity of a streamgage location. Most simulations underestimate the number of no- and low-flow days a streamgage experiences and overestimates the magnitude of low-flows. The ability to accurately model non-perennial systems is paramount to draw inferences about the connections between hydrologic characteristics of low- and no-flow and the potential ecological, biogeochemical, and societal implications of these important systems. Our findings suggest that improving our predictive understanding of non-perennial streamflow of rivers and streams within the Pacific Northwest will fill critical gaps and better target the timing and location of future research, management, and conservation efforts as well as improve the usability of these models for a wider audience of practitioners across fields.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"30 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145903631","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}
Ludwig Strötz, Matti Leppäranta, Kaarina Weckström, Maija Heikkilä, Jan Weckström
The Arctic is the fastest-warming region globally. Lake ice is a sentinel indicator of Arctic change, with wide impacts on hydrological regimes, biodiversity, and ecosystem services. While small lakes are ubiquitous across northern boreal and tundra zones, ice observations remain biased toward large lakes with distinct freezing and melting dynamics. We present high-resolution, field camera-based ice phenology records of 10 small lakes (2–20 ha) in northwest Finnish Lapland spanning low (LE, ∼300 m) and high (HE, 770–1,010 m) elevations over two consecutive seasons. Ice-on timing was uniform across elevations, occurring at cumulative degree-day sums of −10°C·d on shallow LE lakes, and −30°C·d on deeper HE lakes. Thawing from groundwater upwelling was observed across many LE lakes. While the recorded melting process at LE occurred over several days during late May, at HE it extended over weeks into late June to early July, due to long-lasting continuous snow cover, cold meltwater inflow, and increased sublimation. Our thermodynamic lake ice model accurately predicted total ice thickness (R = 0.99, RMSE ≤ 5.8 cm), reaching ∼80 cm at LE and ∼100 cm at HE, but the snow-ice fraction was underpredicted. Freezing and melting were strongly modulated by snow, highlighting the impact of future precipitation changes on ice thickness, quality, and ice-off timing. The rapid and spatially uniform freezing suggests a direct response of small lake phenology to Arctic warming—unlike large lakes, where the summer heat storage, depth, and turbulent mixing are important modulators.
{"title":"Ice Phenology and Thickness in Small Arctic Lakes: Field Observations and Mechanistic Controls","authors":"Ludwig Strötz, Matti Leppäranta, Kaarina Weckström, Maija Heikkilä, Jan Weckström","doi":"10.1029/2025wr041332","DOIUrl":"https://doi.org/10.1029/2025wr041332","url":null,"abstract":"The Arctic is the fastest-warming region globally. Lake ice is a sentinel indicator of Arctic change, with wide impacts on hydrological regimes, biodiversity, and ecosystem services. While small lakes are ubiquitous across northern boreal and tundra zones, ice observations remain biased toward large lakes with distinct freezing and melting dynamics. We present high-resolution, field camera-based ice phenology records of 10 small lakes (2–20 ha) in northwest Finnish Lapland spanning low (LE, ∼300 m) and high (HE, 770–1,010 m) elevations over two consecutive seasons. Ice-on timing was uniform across elevations, occurring at cumulative degree-day sums of −10°C·d on shallow LE lakes, and −30°C·d on deeper HE lakes. Thawing from groundwater upwelling was observed across many LE lakes. While the recorded melting process at LE occurred over several days during late May, at HE it extended over weeks into late June to early July, due to long-lasting continuous snow cover, cold meltwater inflow, and increased sublimation. Our thermodynamic lake ice model accurately predicted total ice thickness (<i>R</i> = 0.99, RMSE ≤ 5.8 cm), reaching ∼80 cm at LE and ∼100 cm at HE, but the snow-ice fraction was underpredicted. Freezing and melting were strongly modulated by snow, highlighting the impact of future precipitation changes on ice thickness, quality, and ice-off timing. The rapid and spatially uniform freezing suggests a direct response of small lake phenology to Arctic warming—unlike large lakes, where the summer heat storage, depth, and turbulent mixing are important modulators.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"40 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145897764","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}
K. L. P. Warburton, J. Del Vecchio, C. R. Meyer, M. C. Palucis
On some frozen hillslopes, subsurface water above permafrost is routed through regularly spaced, linear features known as water tracks, which are active sources of greenhouse gas release. We test whether water tracks form through thermal channelization, where heat from viscous dissipation in flowpaths deepens the thaw, creating a preferred flow path that attracts more water. We derive equations for suprapermafrost Darcy flow—that occurring in unfrozen ground (the active layer) above perennially frozen soil. Using linear stability analysis, we calculate growth rates and obtain wavelength selection for this system, which we compare to observed water track spacing from the Low Arctic. Our model predictions are sensitive to flow speed, but the predicted cross-slope water track patterns are consistent with observed water track spacing under high flow conditions in the Low Arctic. Our analysis implies that signatures of a warming, wetter climate may be found in reduced inter-track spacing and increasing water track extent.
{"title":"Permafrost Thaw Patterning Through Thermal Channelization","authors":"K. L. P. Warburton, J. Del Vecchio, C. R. Meyer, M. C. Palucis","doi":"10.1029/2025wr040569","DOIUrl":"https://doi.org/10.1029/2025wr040569","url":null,"abstract":"On some frozen hillslopes, subsurface water above permafrost is routed through regularly spaced, linear features known as water tracks, which are active sources of greenhouse gas release. We test whether water tracks form through thermal channelization, where heat from viscous dissipation in flowpaths deepens the thaw, creating a preferred flow path that attracts more water. We derive equations for suprapermafrost Darcy flow—that occurring in unfrozen ground (the active layer) above perennially frozen soil. Using linear stability analysis, we calculate growth rates and obtain wavelength selection for this system, which we compare to observed water track spacing from the Low Arctic. Our model predictions are sensitive to flow speed, but the predicted cross-slope water track patterns are consistent with observed water track spacing under high flow conditions in the Low Arctic. Our analysis implies that signatures of a warming, wetter climate may be found in reduced inter-track spacing and increasing water track extent.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"182 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2026-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894490","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}
At many petroleum hydrocarbon spill sites, residual spilled product forms a long-term source of groundwater contamination. The phrase source zone natural depletion is used to refer to the mass loss rates. Overall mass lost under environmental conditions was analyzed using conservative biomarker concentrations for a 1979 oil spill in northern Minnesota, USA. After 40–41 years, an average of 50% of the mass was lost with values ranging from 22% to 57% depending on location. It is also important to understand the composition changes in the source. To understand controls on the losses of individual compounds, concentrations of volatile hydrocarbons in oil samples were compared with aqueous solubilities, and pore-space oil saturations. The results of the comparison show that losses of the oil compounds were controlled by pore-space oil saturations, solubility, and susceptibility to degradation under methanogenic conditions. Compounds that degrade under methanogenic conditions, including toluene, o-xylene, and n-alkanes are more depleted compared to benzene, ethylbenzene, and m- and p-xylene for which losses are dominated by dissolution. These rates and compound-specific behaviors form a foundation for improved modeling approaches and risk analyses.
{"title":"Natural Source Zone Depletion of Crude Oil in the Subsurface: Processes Controlling Mass Losses of Individual Compounds","authors":"Barbara A. Bekins, William N. Herkelrath","doi":"10.1029/2025wr041964","DOIUrl":"https://doi.org/10.1029/2025wr041964","url":null,"abstract":"At many petroleum hydrocarbon spill sites, residual spilled product forms a long-term source of groundwater contamination. The phrase source zone natural depletion is used to refer to the mass loss rates. Overall mass lost under environmental conditions was analyzed using conservative biomarker concentrations for a 1979 oil spill in northern Minnesota, USA. After 40–41 years, an average of 50% of the mass was lost with values ranging from 22% to 57% depending on location. It is also important to understand the composition changes in the source. To understand controls on the losses of individual compounds, concentrations of volatile hydrocarbons in oil samples were compared with aqueous solubilities, and pore-space oil saturations. The results of the comparison show that losses of the oil compounds were controlled by pore-space oil saturations, solubility, and susceptibility to degradation under methanogenic conditions. Compounds that degrade under methanogenic conditions, including toluene, <i>o</i>-xylene, and <i>n</i>-alkanes are more depleted compared to benzene, ethylbenzene, and <i>m</i>- and <i>p</i>-xylene for which losses are dominated by dissolution. These rates and compound-specific behaviors form a foundation for improved modeling approaches and risk analyses.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"47 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894497","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}
Deep learning (DL) models such as Long-Short-Term-Memory (LSTM) networks have achieved exceptional predictive accuracy in rainfall–runoff modeling. Yet these models learn from statistical correlations rather than hydrologic insights, raising the question of whether their internal functional reasoning is physically reliable. Despite previous studies highlighting unexpected outcomes from LSTMs under long-term climate shifts, functional realism—defined as the extent to which a model's internal functioning aligns with defensible mechanisms of streamflow generation—remains largely underexplored. We introduce a hydrology-specific Explainable AI (XAI) framework that opens the black-box of LSTM. It extracts nonlinear, lag-dependent, and time-varying Impulse Response Functions (IRFs) which quantify the functional relationships that LSTM uses to reflect the isolated influence of precipitation (P), temperature (T), and potential evapotranspiration (PET) on simulated streamflow. IRFs reveal how LSTMs internalize streamflow generation during events, offering a catchment hydrology perspective for evaluating model realism. Applying this framework to 672 North American catchments with strong LSTM predictive skill, we find that high accuracy often masks hydrologically implausible reasoning: in over 70% of rain-dominated basins, short-term temperature rises unexpectedly raise simulated streamflow and enhance celerity rate even without rainfall; in snow-dominated regions, PET is misattributed as a driver of snowmelt-related flow and enhances the catchment's celerity rate. We conclude that correlation-driven learning can compromise the robustness of LSTM-based forecasts under weather extremes and short-term and long-term climatic shifts. Our framework bridges deep learning with hydrologic understanding and offers a scalable diagnostic for assessing the functional realism of DL models across diverse catchment types.
{"title":"Evaluating the Functional Realism of Deep Learning Rainfall-Runoff Models Using Catchment Hydrology Principles","authors":"Ara Bayati, Ali A. Ameli, Saman Razavi","doi":"10.1029/2025wr040076","DOIUrl":"https://doi.org/10.1029/2025wr040076","url":null,"abstract":"Deep learning (DL) models such as Long-Short-Term-Memory (LSTM) networks have achieved exceptional predictive accuracy in rainfall–runoff modeling. Yet these models learn from statistical correlations rather than hydrologic insights, raising the question of whether their internal functional reasoning is physically reliable. Despite previous studies highlighting unexpected outcomes from LSTMs under long-term climate shifts, functional realism—defined as the extent to which a model's internal functioning aligns with defensible mechanisms of streamflow generation—remains largely underexplored. We introduce a hydrology-specific Explainable AI (XAI) framework that opens the black-box of LSTM. It extracts nonlinear, lag-dependent, and time-varying Impulse Response Functions (IRFs) which quantify the functional relationships that LSTM uses to reflect the isolated influence of precipitation (<i>P</i>), temperature (<i>T</i>), and potential evapotranspiration (<i>PET</i>) on simulated streamflow. IRFs reveal how LSTMs internalize streamflow generation during events, offering a catchment hydrology perspective for evaluating model realism. Applying this framework to 672 North American catchments with strong LSTM predictive skill, we find that high accuracy often masks hydrologically implausible reasoning: in over 70% of rain-dominated basins, short-term temperature rises unexpectedly raise simulated streamflow and enhance celerity rate even without rainfall; in snow-dominated regions, <i>PET</i> is misattributed as a driver of snowmelt-related flow and enhances the catchment's celerity rate. We conclude that correlation-driven learning can compromise the robustness of LSTM-based forecasts under weather extremes and short-term and long-term climatic shifts. Our framework bridges deep learning with hydrologic understanding and offers a scalable diagnostic for assessing the functional realism of DL models across diverse catchment types.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"6 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894495","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}
Ruolan Yu, Chen Zhang, Mengfen Liu, Michael T. Brett
The role of periphyton in lake phosphorus cycling has long been overlooked or simplified, as water quality models often classify periphyton parameters as non-sensitive, thereby masking their key roles in phosphorus cycling. Therefore, to quantify how periphyton influence phosphorus cycling and related limnological processes, we conducted over 11,000 sensitivity analyses across a wide range of hydrologic and seasonal variations, comparing simulations with and without periphyton processes (PERI vs. noPERI) in the Spokane River and Lake Spokane model. Results showed that excluding periphyton increased spring average epilimnetic total phosphorus (TP) by up to ∼15% due to orthophosphate (PO4) accumulation, while early summer TP decreased by up to ∼7% because of reduced labile dissolved organic matter phosphorus (LDOMP). Concurrently, the chlorophyll-a (Chla) peak advanced from early July to late May (∼41 days), and minimum volume-weighted hypolimnetic dissolved oxygen concentration (DOMIN) decreased by ∼7% in spring. Periphyton regulate phosphorus cycling primarily through two mechanisms: (a) reducing PO4 via growth-driven uptake while enhancing LDOMP through mortality-driven release, leading to seasonally varying contributions to TP; and (b) influencing sediment–water phosphorus exchange and shaping cycling dynamics through direct and indirect competition with phytoplankton. Although sediment oxygen demand parameters were the most sensitive overall and phytoplankton parameters contributed substantially, periphyton parameters that were initially non-sensitive became sensitive under winter conditions and at both low and high flows. This study shows that periphyton can play an important role in long-term phosphorus dynamics, and that dynamically incorporating periphyton processes in models of seasonally stratified lakes can improve water quality management.
{"title":"The Masked Role of Periphyton in Phosphorus Cycling: Mechanistic Insights Under Large-Scale Hydrologic and Seasonal Variability","authors":"Ruolan Yu, Chen Zhang, Mengfen Liu, Michael T. Brett","doi":"10.1029/2025wr041368","DOIUrl":"https://doi.org/10.1029/2025wr041368","url":null,"abstract":"The role of periphyton in lake phosphorus cycling has long been overlooked or simplified, as water quality models often classify periphyton parameters as non-sensitive, thereby masking their key roles in phosphorus cycling. Therefore, to quantify how periphyton influence phosphorus cycling and related limnological processes, we conducted over 11,000 sensitivity analyses across a wide range of hydrologic and seasonal variations, comparing simulations with and without periphyton processes (PERI vs. noPERI) in the Spokane River and Lake Spokane model. Results showed that excluding periphyton increased spring average epilimnetic total phosphorus (TP) by up to ∼15% due to orthophosphate (PO<sub>4</sub>) accumulation, while early summer TP decreased by up to ∼7% because of reduced labile dissolved organic matter phosphorus (LDOMP). Concurrently, the chlorophyll-a (Chl<i>a</i>) peak advanced from early July to late May (∼41 days), and minimum volume-weighted hypolimnetic dissolved oxygen concentration (DO<sub>MIN</sub>) decreased by ∼7% in spring. Periphyton regulate phosphorus cycling primarily through two mechanisms: (a) reducing PO<sub>4</sub> via growth-driven uptake while enhancing LDOMP through mortality-driven release, leading to seasonally varying contributions to TP; and (b) influencing sediment–water phosphorus exchange and shaping cycling dynamics through direct and indirect competition with phytoplankton. Although sediment oxygen demand parameters were the most sensitive overall and phytoplankton parameters contributed substantially, periphyton parameters that were initially non-sensitive became sensitive under winter conditions and at both low and high flows. This study shows that periphyton can play an important role in long-term phosphorus dynamics, and that dynamically incorporating periphyton processes in models of seasonally stratified lakes can improve water quality management.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"55 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894496","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}
Han Jiang, Bowen Shi, Chao-Zhong Qin, Christoph Arns, S. Majid Hassanizadeh
Understanding two-phase flow in laminated sandstones is important for fluid migration control and operational strategy determination in underground energy and hydrology engineering projects. Digital core analysis provides unparalleled understanding of two-phase flow in complex porous media, but the integration into field analytical workflow is obstructed by the huge computational burden and imaging limitations on a standard rock core. To address this challenge, we propose a novel pore-scale rock-typing and upscaling approach for fast computation of two-phase flow properties on large three-dimensional digital rock images that contain billions of voxels. Firstly, a heterogeneous rock sample is divided into several homogeneous rock types through data clustering of regional 3D morphological parameters, and their two-phase flow properties are calculated from selected subsamples using in-house pore-network model. The capillary pressure and relative permeability curves of the full digital image are then estimated through quasi-static modeling on the rock type distribution. The excellent agreement between the upscaling results and pore-scale simulations on the full image has verified the effectiveness of this two-phase flow upscaling strategy. With largely reduced computational demands and clearly defined lamination heterogeneity, this approach has demonstrated good potential in bridging the gap between pore-scale and core-scale fluid flow mechanisms. In addition, due to the laminated structural characteristics, we also find a significant reduction in phase mobility over a range of saturations in the relative permeability curves of this highly permeable rock sample.
{"title":"Pore-Scale Rock-Typing and Upscaling of Relative Permeability on a Laminated Sandstone Through Minkowski Measures","authors":"Han Jiang, Bowen Shi, Chao-Zhong Qin, Christoph Arns, S. Majid Hassanizadeh","doi":"10.1029/2025wr041036","DOIUrl":"https://doi.org/10.1029/2025wr041036","url":null,"abstract":"Understanding two-phase flow in laminated sandstones is important for fluid migration control and operational strategy determination in underground energy and hydrology engineering projects. Digital core analysis provides unparalleled understanding of two-phase flow in complex porous media, but the integration into field analytical workflow is obstructed by the huge computational burden and imaging limitations on a standard rock core. To address this challenge, we propose a novel pore-scale rock-typing and upscaling approach for fast computation of two-phase flow properties on large three-dimensional digital rock images that contain billions of voxels. Firstly, a heterogeneous rock sample is divided into several homogeneous rock types through data clustering of regional 3D morphological parameters, and their two-phase flow properties are calculated from selected subsamples using in-house pore-network model. The capillary pressure and relative permeability curves of the full digital image are then estimated through quasi-static modeling on the rock type distribution. The excellent agreement between the upscaling results and pore-scale simulations on the full image has verified the effectiveness of this two-phase flow upscaling strategy. With largely reduced computational demands and clearly defined lamination heterogeneity, this approach has demonstrated good potential in bridging the gap between pore-scale and core-scale fluid flow mechanisms. In addition, due to the laminated structural characteristics, we also find a significant reduction in phase mobility over a range of saturations in the relative permeability curves of this highly permeable rock sample.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"35 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894498","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}
Natural landslide dams pose severe hazards when they fail, and understanding their breach processes remain challenging because such events are rarely observed directly in the field. To address this gap, we conducted large-scale overtopping experiments with compacted (CP) and non-compacted (NCP) dams, supported by a synchronized multi-sensor framework that combined UAV and ground-based photogrammetry, particle tracking velocimetry, water level gauges, autonomous scouring particles, and seismic monitoring. In situ density tests confirmed that CP dams had higher dry bulk volumetric weight and lower water content (2.33 t/m3, 4.9%) than NCP dams (2.04–1.98 t/m3, 6.8%–4.4%), corresponding to compaction levels of ∼104% for CP and 88%–89% for NCP. The multi-sensor observations captured both surface and subsurface processes throughout failure, revealing that CP dams breached rapidly with sharp peak discharges and narrow, deeply incised channels, whereas NCP dams breached more gradually, producing flatter hydrographs and wider, shallower channels. Despite these differences, the underwater cross-sections consistently evolved toward parabolic geometries. In addition, several characteristic signatures were observed across data sets, including concentrated velocity jets in CP versus dispersed flows in NCP, and V-shaped seismic spectrograms observed during the processes of incision and widening. Because these experiments are approximately five times larger than typical laboratory flume studies, they captured scale-dependent behaviors not observable in smaller facilities, including slower incision rates, later peak discharges, and more gradual hydrograph development at larger scale. These findings clarify how compaction and scale jointly influence breach timing and erosion pathways and provide physically grounded constraints for improving numerical breach models and hazard assessments.
{"title":"Synchronized Multidisciplinary Observations in Large-Scale Dam Breach Experiments to Enhance the Understanding of Dam Failure Evolution","authors":"Su-Chin Chen, Chi-Yao Hung, Pei-Yi Chen, Samkele S. Tfwala, Min-Chih Liang, Chen-Han Jiang, Wei-An Chao","doi":"10.1029/2025wr040786","DOIUrl":"https://doi.org/10.1029/2025wr040786","url":null,"abstract":"Natural landslide dams pose severe hazards when they fail, and understanding their breach processes remain challenging because such events are rarely observed directly in the field. To address this gap, we conducted large-scale overtopping experiments with compacted (CP) and non-compacted (NCP) dams, supported by a synchronized multi-sensor framework that combined UAV and ground-based photogrammetry, particle tracking velocimetry, water level gauges, autonomous scouring particles, and seismic monitoring. In situ density tests confirmed that CP dams had higher dry bulk volumetric weight and lower water content (2.33 t/m<sup>3</sup>, 4.9%) than NCP dams (2.04–1.98 t/m<sup>3</sup>, 6.8%–4.4%), corresponding to compaction levels of ∼104% for CP and 88%–89% for NCP. The multi-sensor observations captured both surface and subsurface processes throughout failure, revealing that CP dams breached rapidly with sharp peak discharges and narrow, deeply incised channels, whereas NCP dams breached more gradually, producing flatter hydrographs and wider, shallower channels. Despite these differences, the underwater cross-sections consistently evolved toward parabolic geometries. In addition, several characteristic signatures were observed across data sets, including concentrated velocity jets in CP versus dispersed flows in NCP, and V-shaped seismic spectrograms observed during the processes of incision and widening. Because these experiments are approximately five times larger than typical laboratory flume studies, they captured scale-dependent behaviors not observable in smaller facilities, including slower incision rates, later peak discharges, and more gradual hydrograph development at larger scale. These findings clarify how compaction and scale jointly influence breach timing and erosion pathways and provide physically grounded constraints for improving numerical breach models and hazard assessments.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"3 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894501","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}
Pengdong Yan, Hongwei Lu, Yuxuan Wang, Yiming Yan, Zhucheng Zhang, Mengxi He, Hengchen Li, Jun Xia, Li He
Little has been known whether intensified global population aging has an independent effect on water use (which corresponds to the global water security). We here use panel analysis to quantitatively find out an obvious declining effect of global population aging (measured by proportion of aged population) on water use (measured by total water withdrawal (TWW)) based on the data of 168 countries in 1987–2018 and then analyze the potential mechanisms leading to the effect. We find that the estimated coefficient regarding the aging effect (β) is about −0.0217, indicating that each percent of increase in proportion of aged population caused 2.17 percent decline in TWW. We further demonstrate the obvious aging effect at the country scale using the gridded data from 2000 to 2010. We eventually project that the global aging effect will lead to about 15%–31% of declines in water use under scenarios SSP1 to SSP5 by 2050.
{"title":"The Global Declining Effect of Population Aging on Water Use","authors":"Pengdong Yan, Hongwei Lu, Yuxuan Wang, Yiming Yan, Zhucheng Zhang, Mengxi He, Hengchen Li, Jun Xia, Li He","doi":"10.1029/2024wr037685","DOIUrl":"https://doi.org/10.1029/2024wr037685","url":null,"abstract":"Little has been known whether intensified global population aging has an independent effect on water use (which corresponds to the global water security). We here use panel analysis to quantitatively find out an obvious declining effect of global population aging (measured by proportion of aged population) on water use (measured by total water withdrawal (TWW)) based on the data of 168 countries in 1987–2018 and then analyze the potential mechanisms leading to the effect. We find that the estimated coefficient regarding the aging effect (<i>β</i>) is about −0.0217, indicating that each percent of increase in proportion of aged population caused 2.17 percent decline in TWW. We further demonstrate the obvious aging effect at the country scale using the gridded data from 2000 to 2010. We eventually project that the global aging effect will lead to about 15%–31% of declines in water use under scenarios SSP1 to SSP5 by 2050.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"2020 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145894500","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：