Xinghua Xu, Xiayang Yu, Junjie Wu, Kai Xiao, Pei Xin
Soil temperature is crucial for the ecological functions of coastal wetlands. While the impact of tides on porewater flow is well recognized, their effect on soil temperature, which is also closely related to hydrodynamic processes, has not been sufficiently explored. This study investigates how dynamic tidal and atmospheric conditions interact to drive temperature variations in coastal wetlands, based on both laboratory experiments and numerical simulations. The results reveal that temperature plumes develop near creek banks, where the annual mean soil temperature closely correlates with tidal temperature. Tide-induced water circulation enhances local heat transfer and mixing, leading to moderate annual temperature ranges in areas close to creeks. In contrast, surface soil temperatures across the wetland platform are closer to atmospheric conditions in both annual mean values and ranges. At the field scale, tide-induced advective heat exchange is apparent, particularly near creeks. However, its net impact on the overall heat balance is relatively limited compared to the conductive heat flux at the sediment-water interface. The study also highlights the role of macropores in enhancing local temperature fluctuations by augmenting advective heat exchange and increasing heat capacity. Additionally, increased hydraulic and thermal conductivities in wetland sediments could result in more efficient temperature transfer and larger temperature ranges in deeper soil layers. These findings advance our understanding of the hydrodynamic and thermal processes in coastal wetlands coupled with benthic bioturbation.
{"title":"Tidal Influences on Temperature Dynamics and Heat Exchange in Coastal Wetlands","authors":"Xinghua Xu, Xiayang Yu, Junjie Wu, Kai Xiao, Pei Xin","doi":"10.1029/2024wr038374","DOIUrl":"https://doi.org/10.1029/2024wr038374","url":null,"abstract":"Soil temperature is crucial for the ecological functions of coastal wetlands. While the impact of tides on porewater flow is well recognized, their effect on soil temperature, which is also closely related to hydrodynamic processes, has not been sufficiently explored. This study investigates how dynamic tidal and atmospheric conditions interact to drive temperature variations in coastal wetlands, based on both laboratory experiments and numerical simulations. The results reveal that temperature plumes develop near creek banks, where the annual mean soil temperature closely correlates with tidal temperature. Tide-induced water circulation enhances local heat transfer and mixing, leading to moderate annual temperature ranges in areas close to creeks. In contrast, surface soil temperatures across the wetland platform are closer to atmospheric conditions in both annual mean values and ranges. At the field scale, tide-induced advective heat exchange is apparent, particularly near creeks. However, its net impact on the overall heat balance is relatively limited compared to the conductive heat flux at the sediment-water interface. The study also highlights the role of macropores in enhancing local temperature fluctuations by augmenting advective heat exchange and increasing heat capacity. Additionally, increased hydraulic and thermal conductivities in wetland sediments could result in more efficient temperature transfer and larger temperature ranges in deeper soil layers. These findings advance our understanding of the hydrodynamic and thermal processes in coastal wetlands coupled with benthic bioturbation.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"49 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435797","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}
Tao Wang, Chenming Zhang, David Andrew Barry, Jiansheng Chen, Yuan Wang, Jie Ren, Ling Li
Submarine groundwater discharge from subterranean estuaries is affected by tides, which are represented in computational models as time-dependent boundary conditions on the seaward boundary. Conventionally, a small time step is used in the numerical model to phase-resolve the tidal signal so as to ensure accurate results, although at the cost of excessive computation times for long-term simulations. This study proposes a highly efficient alternative method for modeling the tidal signal, in which a phase-averaged pressure is assigned to the seawater boundary with a much larger time step. The assigned pressure condition is first determined from an analytical solution of the time-independent pressure boundary condition. Along with the analytical solution, a single calibration factor is introduced at the beach face to account for the conductance at the beach. This results in good agreement between the results for phase-averaged and phase-resolved simulations. The new method is verified by comparison of the results for a wide range of physical cases determined using TOUGHREACT, a model for simulating coupled hydrodynamic, thermodynamic, and geochemical processes. This comparison shows that the phase-averaged results give good agreement except for a small underestimation of the mixing zone over the saltwater wedge region. These results confirm that the new boundary condition is suitable for efficient, long-term simulations of coastal aquifers subjected to tidal forcing.
{"title":"Efficient Implementation of Tidal Forcing in Simulations of Groundwater Dynamics in Subterranean Estuaries","authors":"Tao Wang, Chenming Zhang, David Andrew Barry, Jiansheng Chen, Yuan Wang, Jie Ren, Ling Li","doi":"10.1029/2024wr038145","DOIUrl":"https://doi.org/10.1029/2024wr038145","url":null,"abstract":"Submarine groundwater discharge from subterranean estuaries is affected by tides, which are represented in computational models as time-dependent boundary conditions on the seaward boundary. Conventionally, a small time step is used in the numerical model to phase-resolve the tidal signal so as to ensure accurate results, although at the cost of excessive computation times for long-term simulations. This study proposes a highly efficient alternative method for modeling the tidal signal, in which a phase-averaged pressure is assigned to the seawater boundary with a much larger time step. The assigned pressure condition is first determined from an analytical solution of the time-independent pressure boundary condition. Along with the analytical solution, a single calibration factor is introduced at the beach face to account for the conductance at the beach. This results in good agreement between the results for phase-averaged and phase-resolved simulations. The new method is verified by comparison of the results for a wide range of physical cases determined using TOUGHREACT, a model for simulating coupled hydrodynamic, thermodynamic, and geochemical processes. This comparison shows that the phase-averaged results give good agreement except for a small underestimation of the mixing zone over the saltwater wedge region. These results confirm that the new boundary condition is suitable for efficient, long-term simulations of coastal aquifers subjected to tidal forcing.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"15 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427305","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}
Eiji Masunaga, Oliver B. Fringer, Tatsumi Kitamura, Takao Ouchi
This study presents results of circulation and residence time in lakes influenced by wind-induced mixing investigated with numerical simulations. The study area is Lake Kasumigaura, a continuous lake system primally consisting of two lakes, West Lake and North Lake. Although metrological conditions and depths are similar for both lakes, the surface area and shape of the lakes are very different. A numerical model resolves the primary features of the wind-driven circulation in the lake system and is forced by observed river discharges and wind stress. A passive tracer released from the river mouths is used to estimate the residence time and evaluate mixing processes. Wind-driven flow dominates the kinetic energy in the lakes and induces chaotic motions leading to tracer dispersion which is largely influenced by the shape of the lakes. Results indicate that the residence time is much longer in the well-mixed middle basin of West Lake than North Lake. The estimated horizontal tracer diffusivity is approximately three times larger for the large West Lake than for the small-narrow North Lake. This study suggests that the surface area and shape of lakes in which the flow is predominantly wind driven largely influences circulation, water exchange processes and residence times in lakes.
{"title":"The Influence of Horizontal Dispersion on Residence Times in Shallow Lakes","authors":"Eiji Masunaga, Oliver B. Fringer, Tatsumi Kitamura, Takao Ouchi","doi":"10.1029/2024wr037509","DOIUrl":"https://doi.org/10.1029/2024wr037509","url":null,"abstract":"This study presents results of circulation and residence time in lakes influenced by wind-induced mixing investigated with numerical simulations. The study area is Lake Kasumigaura, a continuous lake system primally consisting of two lakes, West Lake and North Lake. Although metrological conditions and depths are similar for both lakes, the surface area and shape of the lakes are very different. A numerical model resolves the primary features of the wind-driven circulation in the lake system and is forced by observed river discharges and wind stress. A passive tracer released from the river mouths is used to estimate the residence time and evaluate mixing processes. Wind-driven flow dominates the kinetic energy in the lakes and induces chaotic motions leading to tracer dispersion which is largely influenced by the shape of the lakes. Results indicate that the residence time is much longer in the well-mixed middle basin of West Lake than North Lake. The estimated horizontal tracer diffusivity is approximately three times larger for the large West Lake than for the small-narrow North Lake. This study suggests that the surface area and shape of lakes in which the flow is predominantly wind driven largely influences circulation, water exchange processes and residence times in lakes.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"52 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435760","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}
Chuanhao Wu, Pat J.-F. Yeh, Tian Yao, Zhengjie Gong, Jie Niu, Shanshui Yuan
Terrestrial water storage change (ΔS) is an important indicator of climate change that can monitor and predict hydrological changes. However, the interactions between ΔS and climate, vegetation, and soil factors add complexity in temporal variability of ΔS, particularly at seasonal scale. Here, we conduct a systematic assessment in the roles that seasonal variabilities of climate and vegetation modulate seasonal variability of ΔS in 769 basins covering a wide range of climate regimes and vegetation types globally. The variance decomposition method of ΔS based on the Budyko framework is used to estimate the contributions of climate factors (precipitation P and potential evapotranspiration PET) and runoff (R) to ΔS variability for different vegetation types. Results indicate that the increased climatic (P, PET) and R seasonal variabilities enhances ΔS seasonal variability under both in-phase (IP) and out-of-phase (OP) seasonal relations between P and PET, with a larger contribution from P than PET and R. However, the P-PET covariance tends to reduce (enhance) ΔS seasonal variability under the IP (OP) relation, while the P-R covariance tends to reduce ΔS variability for both IP and OP relations. Climate seasonality influencing ΔS is regulated through vegetation dynamics, mainly via extending plant roots to access deeper soil water under water stress or by seasonally adapting water use efficiency and primary production. The growth of seasonal vegetation under the IP P-PET relation can cope with limited soil water, while the growth of evergreen vegetation under OP P-PET relation depends on soil water availability throughout the year.
{"title":"Controls of Climate Seasonality and Vegetation Dynamics on the Seasonal Variability of Terrestrial Water Storage Under Diverse Climate Regimes","authors":"Chuanhao Wu, Pat J.-F. Yeh, Tian Yao, Zhengjie Gong, Jie Niu, Shanshui Yuan","doi":"10.1029/2024wr038065","DOIUrl":"https://doi.org/10.1029/2024wr038065","url":null,"abstract":"Terrestrial water storage change (Δ<i>S</i>) is an important indicator of climate change that can monitor and predict hydrological changes. However, the interactions between Δ<i>S</i> and climate, vegetation, and soil factors add complexity in temporal variability of Δ<i>S</i>, particularly at seasonal scale. Here, we conduct a systematic assessment in the roles that seasonal variabilities of climate and vegetation modulate seasonal variability of Δ<i>S</i> in 769 basins covering a wide range of climate regimes and vegetation types globally. The variance decomposition method of Δ<i>S</i> based on the Budyko framework is used to estimate the contributions of climate factors (precipitation <i>P</i> and potential evapotranspiration <i>PET</i>) and runoff (<i>R</i>) to Δ<i>S</i> variability for different vegetation types. Results indicate that the increased climatic (<i>P</i>, <i>PET</i>) and <i>R</i> seasonal variabilities enhances Δ<i>S</i> seasonal variability under both in-phase (IP) and out-of-phase (OP) seasonal relations between <i>P</i> and <i>PET</i>, with a larger contribution from <i>P</i> than <i>PET</i> and <i>R</i>. However, the <i>P</i>-<i>PET</i> covariance tends to reduce (enhance) Δ<i>S</i> seasonal variability under the IP (OP) relation, while the <i>P</i>-<i>R</i> covariance tends to reduce Δ<i>S</i> variability for both IP and OP relations. Climate seasonality influencing Δ<i>S</i> is regulated through vegetation dynamics, mainly via extending plant roots to access deeper soil water under water stress or by seasonally adapting water use efficiency and primary production. The growth of seasonal vegetation under the IP <i>P</i>-<i>PET</i> relation can cope with limited soil water, while the growth of evergreen vegetation under OP <i>P</i>-<i>PET</i> relation depends on soil water availability throughout the year.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"22 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427304","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}
Existing research on soil erosion primarily focuses on the individual effects of factors such as rainfall intensity, slope gradient, grass cover, and soil characteristics, with limited exploration of the interactions among these factors. This study investigated the mechanisms of soil erosion on overland covered with vegetation in the Loess Plateau region through indoor artificial simulated rainfall experiments. The experiments included six levels of grass coverage (0, 30%, 40%, 50%, 60%, 70%), five grass distribution patterns (DP, CP, VP, SP, HP), five rainfall intensities (60, 80, 90, 100, 120 mm/hr) and three slope gradients (5°, 10°, 15°) to explore the effects of experimental design factors and hydraulic parameters on the overland soil erosion mechanisms. The results show that as the grass coverage increases, the soil erosion rate on the overland decreases. Under different grass distribution patterns, horizontal grass distribution played an important role in inhibiting overland soil erosion rate. The overland soil erosion rate increased following a power function relationship with rising slope steepness and rainfall intensity, with erosion rates being more sensitive to changes in rainfall intensity than slope gradient. Among the six hydraulic parameters, dimensionless stream power was the optimal hydraulic parameters for predicting overland soil erosion rate under grass cover. Furthermore, an overland soil erosion model under the influence of grass cover and rainfall intensity was established based on general dimensionless hydraulic parameters (KGE = 0.931, R2 = 0.912). The model satisfactorily simulates overland soil erosion rate under grass cover and helps to reveal the mechanism of overland soil erosion.
{"title":"Effects of Grass Cover on the Overland Soil Erosion Mechanism Under Simulated Rainfall","authors":"Mingwang Zhang, Kuandi Zhang, Youdong Cen, Pengfei Wang, Junqiang Xia","doi":"10.1029/2023wr036888","DOIUrl":"https://doi.org/10.1029/2023wr036888","url":null,"abstract":"Existing research on soil erosion primarily focuses on the individual effects of factors such as rainfall intensity, slope gradient, grass cover, and soil characteristics, with limited exploration of the interactions among these factors. This study investigated the mechanisms of soil erosion on overland covered with vegetation in the Loess Plateau region through indoor artificial simulated rainfall experiments. The experiments included six levels of grass coverage (0, 30%, 40%, 50%, 60%, 70%), five grass distribution patterns (DP, CP, VP, SP, HP), five rainfall intensities (60, 80, 90, 100, 120 mm/hr) and three slope gradients (5°, 10°, 15°) to explore the effects of experimental design factors and hydraulic parameters on the overland soil erosion mechanisms. The results show that as the grass coverage increases, the soil erosion rate on the overland decreases. Under different grass distribution patterns, horizontal grass distribution played an important role in inhibiting overland soil erosion rate. The overland soil erosion rate increased following a power function relationship with rising slope steepness and rainfall intensity, with erosion rates being more sensitive to changes in rainfall intensity than slope gradient. Among the six hydraulic parameters, dimensionless stream power was the optimal hydraulic parameters for predicting overland soil erosion rate under grass cover. Furthermore, an overland soil erosion model under the influence of grass cover and rainfall intensity was established based on general dimensionless hydraulic parameters (<i>KGE</i> = 0.931, <i>R</i><sup>2</sup> = 0.912). The model satisfactorily simulates overland soil erosion rate under grass cover and helps to reveal the mechanism of overland soil erosion.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"14 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427309","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}
Recent advances in remote sensing of snow using Synthetic Aperture Radar have shown the potential for retrievals of Snow Water Equivalent (SWE) at high spatial resolution with good accuracy. These data can be integrated with physically based models to reconstruct spatial heterogeneity and reduce uncertainty in quantifying SWE. In this study, we present a Multi-Physics Data Assimilation Framework (MPDAF) to improve operational water prediction by assimilating snow measurements/retrievals or microwave data. This framework is demonstrated over Grand Mesa, Colorado during NASA's SnowEx’17 campaign. To illustrate the potential benefit of satellite-based time-series of SAR measurements, we investigate the value of data assimilation (DA) with window lengths determined by potential satellite revisit times and anticipated estimation error models. Daily assimilation of integral quantities like snow depth showed dramatic improvement in predicted snow depth, SWE and in vertical profile of snow density. Independent evaluation against pit measurements shows that assimilation of SWE retrievals from airborne SnowSAR backscatter measurements substantially reduced bias in snow depth (from −22% to 0%) and SWE (from −19% to 3%), also recovering spatial heterogeneity not resolved by weather forecasts. Assimilation impacts both snowpack microphysics and the forward simulation of volume backscatter in X and Ku bands with dependence on snow depth changes. The uncertainty in the forward estimates of backscatter is consistent with the synthetic measurement uncertainty based on pit data, thus demonstrating that MPDAF preserves end-to-end physical consistency among assimilated retrievals and forward simulations of backscatter measurements critical for operational retrievals.
{"title":"Multi-Physics Data Assimilation Framework for Remotely Sensed Snowpacks to Improve Water Prediction","authors":"Prabhakar Shrestha, Ana P. Barros","doi":"10.1029/2024wr037885","DOIUrl":"https://doi.org/10.1029/2024wr037885","url":null,"abstract":"Recent advances in remote sensing of snow using Synthetic Aperture Radar have shown the potential for retrievals of Snow Water Equivalent (SWE) at high spatial resolution with good accuracy. These data can be integrated with physically based models to reconstruct spatial heterogeneity and reduce uncertainty in quantifying SWE. In this study, we present a Multi-Physics Data Assimilation Framework (MPDAF) to improve operational water prediction by assimilating snow measurements/retrievals or microwave data. This framework is demonstrated over Grand Mesa, Colorado during NASA's SnowEx’17 campaign. To illustrate the potential benefit of satellite-based time-series of SAR measurements, we investigate the value of data assimilation (DA) with window lengths determined by potential satellite revisit times and anticipated estimation error models. Daily assimilation of integral quantities like snow depth showed dramatic improvement in predicted snow depth, SWE and in vertical profile of snow density. Independent evaluation against pit measurements shows that assimilation of SWE retrievals from airborne SnowSAR backscatter measurements substantially reduced bias in snow depth (from −22% to 0%) and SWE (from −19% to 3%), also recovering spatial heterogeneity not resolved by weather forecasts. Assimilation impacts both snowpack microphysics and the forward simulation of volume backscatter in X and Ku bands with dependence on snow depth changes. The uncertainty in the forward estimates of backscatter is consistent with the synthetic measurement uncertainty based on pit data, thus demonstrating that MPDAF preserves end-to-end physical consistency among assimilated retrievals and forward simulations of backscatter measurements critical for operational retrievals.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"154 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427307","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}
Reservoir operations face persistent challenges due to increasing water demand, more frequent extreme events, and stricter environmental requirements such as instream flow requirements for endangered species or other aspects of ecosystem health. This paper explores real-world changes in reservoir storage and operation between 1990 and 2019 using historical data from 256 reservoirs across the Contiguous United States (CONUS). Statistical methods are applied to detecting changes in representative storage statistical metrics. Moreover, an empirical reservoir operation model which represents the dynamic change of operation over time is used to detect changes in reservoir operation rule and responses to different water availability and demand conditions under existing rules. The relationship between storage changes and operational changes is explored. Our results uncover significant trends in the storage metrics for 130 reservoirs, more of which show decreasing trends particularly in regions such as the Arkansas-White-Red basin, the Texas-Gulf region, and the southwestern United States, where the storage declined mainly due to sedimentation and drought. Conversely, it is found that increasing trends do not show a clear spatial pattern, that is, the changes are not tied with regions but with operational changes. Additionally, 76 reservoirs are identified with changes in operations via an empirical reservoir operation model. Finally, examining the relationship of operational changes with external environment variables shows evidence of not only the effectiveness of the operations for some reservoirs, but also operation deficiencies for some reservoirs. Notably, sedimentation-related issues and inadequate operational responses during extreme weather events emphasize the need for improved operational policies.
{"title":"The Storage and Operation Changes of 256 Reservoirs Across the Contiguous United States","authors":"Yanan Chen, Ximing Cai","doi":"10.1029/2024wr037372","DOIUrl":"https://doi.org/10.1029/2024wr037372","url":null,"abstract":"Reservoir operations face persistent challenges due to increasing water demand, more frequent extreme events, and stricter environmental requirements such as instream flow requirements for endangered species or other aspects of ecosystem health. This paper explores real-world changes in reservoir storage and operation between 1990 and 2019 using historical data from 256 reservoirs across the Contiguous United States (CONUS). Statistical methods are applied to detecting changes in representative storage statistical metrics. Moreover, an empirical reservoir operation model which represents the dynamic change of operation over time is used to detect changes in reservoir operation rule and responses to different water availability and demand conditions under existing rules. The relationship between storage changes and operational changes is explored. Our results uncover significant trends in the storage metrics for 130 reservoirs, more of which show decreasing trends particularly in regions such as the Arkansas-White-Red basin, the Texas-Gulf region, and the southwestern United States, where the storage declined mainly due to sedimentation and drought. Conversely, it is found that increasing trends do not show a clear spatial pattern, that is, the changes are not tied with regions but with operational changes. Additionally, 76 reservoirs are identified with changes in operations via an empirical reservoir operation model. Finally, examining the relationship of operational changes with external environment variables shows evidence of not only the effectiveness of the operations for some reservoirs, but also operation deficiencies for some reservoirs. Notably, sedimentation-related issues and inadequate operational responses during extreme weather events emphasize the need for improved operational policies.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"29 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143417638","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}
Matthias Beyer, Alberto Iraheta, Malkin Gerchow, Kathrin Kuehnhammer, Ana Claudia Callau-Beyer, Paul Koeniger, David Dubbert, Maren Dubbert, Ricardo Sánchez-Murillo, Christian Birkel
The spatial variation of soil water isotopes (SWI)—representing the baseline for investigating root water uptake (RWU) depths with water stable isotope techniques—has rarely been investigated. Here, we use spatial SWI depth profile sampling in combination with unmanned aerial vehicle (UAV) based land surface temperature estimates and vegetation indices (VI) in order to improving process understanding of the relationships between the spatial variability of soil water content and soil water isotope patterns with canopy status, represented in the form of VI. We carried out a spatial sampling of 10 SWI depth profiles in a tropical dry forest. UAV data were collected and analyzed to obtain detailed characterization of soil temperature and canopy status. We then performed a statistical analysis between the VI and land surface temperatures with soil water content and SWI values at different spatial resolutions (3 cm–5 m). Best relationships were used for generating soil water isoscapes for the entire study area. Results suggest that soil water content and SWI values are strongly mediated by canopy parameters (VI). Various VI correlate strongly with soil water content and SWI values across all depths. SWI at the surface depend on land surface temperature (R2 of 0.66 for δ18O and 0.64 for δ2H). Strongest overall correlations were found at a spatial resolution of 0.5 m. We speculate that this might be the ideal resolution for spatially characterizing SWI patterns and investigate RWU in tropical dry forest environments. Supporting spatial analyses of SWI with UAV-based approaches might be a future avenue for improving the spatial representation and credibility of such studies.
{"title":"UAV-Based Land Surface Temperatures and Vegetation Indices Explain and Predict Spatial Patterns of Soil Water Isotopes in a Tropical Dry Forest","authors":"Matthias Beyer, Alberto Iraheta, Malkin Gerchow, Kathrin Kuehnhammer, Ana Claudia Callau-Beyer, Paul Koeniger, David Dubbert, Maren Dubbert, Ricardo Sánchez-Murillo, Christian Birkel","doi":"10.1029/2024wr037294","DOIUrl":"https://doi.org/10.1029/2024wr037294","url":null,"abstract":"The spatial variation of soil water isotopes (SWI)—representing the baseline for investigating root water uptake (RWU) depths with water stable isotope techniques—has rarely been investigated. Here, we use spatial SWI depth profile sampling in combination with unmanned aerial vehicle (UAV) based land surface temperature estimates and vegetation indices (VI) in order to improving process understanding of the relationships between the spatial variability of soil water content and soil water isotope patterns with canopy status, represented in the form of VI. We carried out a spatial sampling of 10 SWI depth profiles in a tropical dry forest. UAV data were collected and analyzed to obtain detailed characterization of soil temperature and canopy status. We then performed a statistical analysis between the VI and land surface temperatures with soil water content and SWI values at different spatial resolutions (3 cm–5 m). Best relationships were used for generating soil water isoscapes for the entire study area. Results suggest that soil water content and SWI values are strongly mediated by canopy parameters (VI). Various VI correlate strongly with soil water content and SWI values across all depths. SWI at the surface depend on land surface temperature (<i>R</i><sup>2</sup> of 0.66 for δ<sup>18</sup>O and 0.64 for δ<sup>2</sup>H). Strongest overall correlations were found at a spatial resolution of 0.5 m. We speculate that this might be the ideal resolution for spatially characterizing SWI patterns and investigate RWU in tropical dry forest environments. Supporting spatial analyses of SWI with UAV-based approaches might be a future avenue for improving the spatial representation and credibility of such studies.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"10 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143417637","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}
Magdalena Seelig, Simon Seelig, Karl Krainer, Gerfried Winkler
Frozen sediment accumulations, including rock glaciers, talus, and moraines, constitute complex aquifers in permafrost-affected terrain. The spatial distribution of permafrost ice largely governs the flow of water through the subsurface, which exhibits a spectrum of flow patterns, ranging from diffuse flow through a porous matrix to concentrated flow along discrete channels. This study characterizes the groundwater flow system within three active rock glaciers drained by springs in the Austrian Alps. We study the alteration of recharge pulses traveling through the rock glaciers to decipher the dominant flow pattern. Key hydraulic properties are explored through a combined evaluation of spring hydrographs and fluorescence tracer tests. Water predominantly flows through a network of channels within the frozen subsurface. This flow is rapid and highly turbulent, implying high energy dissipation and effective heat transfer. Although the channels exhibit large hydraulic diameters, their irregular structure contributes to exceptionally high frictional resistance. These high energy losses accelerate the melting process and promote flow-melt feedback loops, driving permafrost degradation and facilitating flow concentration. Ultimately, the hydraulic properties of these channel networks influence permafrost thaw, solute transport, lake outburst hazards, and slope stability.
{"title":"Hydraulics of Channelized Flow in Ice-Supersaturated Debris: 1. Rock Glacier Hydrology in Alpine Glacial-Periglacial Systems","authors":"Magdalena Seelig, Simon Seelig, Karl Krainer, Gerfried Winkler","doi":"10.1029/2024wr037235","DOIUrl":"https://doi.org/10.1029/2024wr037235","url":null,"abstract":"Frozen sediment accumulations, including rock glaciers, talus, and moraines, constitute complex aquifers in permafrost-affected terrain. The spatial distribution of permafrost ice largely governs the flow of water through the subsurface, which exhibits a spectrum of flow patterns, ranging from diffuse flow through a porous matrix to concentrated flow along discrete channels. This study characterizes the groundwater flow system within three active rock glaciers drained by springs in the Austrian Alps. We study the alteration of recharge pulses traveling through the rock glaciers to decipher the dominant flow pattern. Key hydraulic properties are explored through a combined evaluation of spring hydrographs and fluorescence tracer tests. Water predominantly flows through a network of channels within the frozen subsurface. This flow is rapid and highly turbulent, implying high energy dissipation and effective heat transfer. Although the channels exhibit large hydraulic diameters, their irregular structure contributes to exceptionally high frictional resistance. These high energy losses accelerate the melting process and promote flow-melt feedback loops, driving permafrost degradation and facilitating flow concentration. Ultimately, the hydraulic properties of these channel networks influence permafrost thaw, solute transport, lake outburst hazards, and slope stability.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"2 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143401677","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}
Pengfei Shi, Kai Lyu, Zhenya Li, Tao Yang, Chong-Yu Xu, Xiaobo Hao, Jiaqing Xiao
The occurrence frequency and catastrophe caused by flooding are increasing rapidly, highlighting the importance of real-time impact-based forecasting. However, traditional approaches primarily based on hydrodynamic models need large computational cost and generally fail to achieve real-time flood mapping, especially for large-scale watersheds. In this work, a novel, simple and convenient approach called Topography-based Flood Inundation Mapping (TOPFIM) is developed to achieve rapid and accurate flood mapping. TOPFIM is characterized by an adaptive river segmentation method and a dynamic inundation volume allocation approach adhering full water volume constraint. The proposed approach is applied to the upper reaches of the Le'an River basin, China, and HEC-RAS is employed as the benchmark for comparison. The results demonstrate that TOPFIM's simulation accuracy for inundation extent approaches that of hydrodynamic models, with an averaged critical success index of 0.83 and hit rate of 0.90 compared to HEC-RAS's simulation. Moreover, TOPFIM generates flood inundation mapping prediction within 10 s rather than hours required by conventional hydrodynamic models. It signifies a pivotal practical enhancement that has the potential to effectively preserve lives and protect assets in times of flood emergencies. Overall, as a simple and convenient tool, TOPFIM demonstrates its potential for real-time flood inundation mapping and risk analysis.
{"title":"A Novel Topography-Based Approach for Real-Time Flood Inundation Mapping","authors":"Pengfei Shi, Kai Lyu, Zhenya Li, Tao Yang, Chong-Yu Xu, Xiaobo Hao, Jiaqing Xiao","doi":"10.1029/2024wr037851","DOIUrl":"https://doi.org/10.1029/2024wr037851","url":null,"abstract":"The occurrence frequency and catastrophe caused by flooding are increasing rapidly, highlighting the importance of real-time impact-based forecasting. However, traditional approaches primarily based on hydrodynamic models need large computational cost and generally fail to achieve real-time flood mapping, especially for large-scale watersheds. In this work, a novel, simple and convenient approach called Topography-based Flood Inundation Mapping (TOPFIM) is developed to achieve rapid and accurate flood mapping. TOPFIM is characterized by an adaptive river segmentation method and a dynamic inundation volume allocation approach adhering full water volume constraint. The proposed approach is applied to the upper reaches of the Le'an River basin, China, and HEC-RAS is employed as the benchmark for comparison. The results demonstrate that TOPFIM's simulation accuracy for inundation extent approaches that of hydrodynamic models, with an averaged critical success index of 0.83 and hit rate of 0.90 compared to HEC-RAS's simulation. Moreover, TOPFIM generates flood inundation mapping prediction within 10 s rather than hours required by conventional hydrodynamic models. It signifies a pivotal practical enhancement that has the potential to effectively preserve lives and protect assets in times of flood emergencies. Overall, as a simple and convenient tool, TOPFIM demonstrates its potential for real-time flood inundation mapping and risk analysis.","PeriodicalId":23799,"journal":{"name":"Water Resources Research","volume":"29 1","pages":""},"PeriodicalIF":5.4,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143401675","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：