HESS - recent papers

Evaluating different roughness approaches and infiltration parameters for vegetation-influenced overland flow in hydrological model

Wed, 02 Sep 2026 15:21:51 +0200

Evaluating different roughness approaches and infiltration parameters for vegetation-influenced overland flow in hydrological model
Azam Masoodi and Philipp Kraft
Hydrol. Earth Syst. Sci., 30, 5551–5570, https://doi.org/10.5194/hess-30-5551-2026, 2026
Vegetation affects surface runoff in several ways. Surface roughness is increased by stems and leaves, roots and their remnants enhance infiltration into the soil, and through evaporation, the soil water content changes at the beginning of a rainfall event. Our study investigates, how a simulation model is able to react to these effects. While roughness and infiltration are well covered, initial soil moisture is still an unsolved problem.

Integrating Physical-Based Xinanjiang Model and Deep Learning for Interpretable Streamflow Simulation: A Multi-Source Data Fusion Approach across Diverse Chinese Basins

Tue, 01 Sep 2026 15:21:51 +0200

Integrating Physical-Based Xinanjiang Model and Deep Learning for Interpretable Streamflow Simulation: A Multi-Source Data Fusion Approach across Diverse Chinese Basins
Zhaocai Wang, Nannan Xu, Wei Song, Xingxing Zhang, Junhao Wu, and Xi Chen
Hydrol. Earth Syst. Sci., 30, 5521–5549, https://doi.org/10.5194/hess-30-5521-2026, 2026
This study integrates Xinanjiang (XAJ) and Temporal Convolutional Network - Gated Recurrent Unit (TCN-GRU) via Random Forest (RF) for streamflow simulation. It combines XAJ’s physical modeling with TCN-GRU’s temporal analysis. Validated in four hydrologically diverse basins, the model achieves Nash-Sutcliffe Efficiency (NSE) 0.971–0.991, outperforming traditional models. Robust in flood/interval simulations, analysis identifies dew point temperature and evaporation as key factors through three interpretable methods.

Validation of the open-source hydrodynamic model SFINCS on historical river floods at the global scale

Tue, 01 Sep 2026 15:21:51 +0200

Validation of the open-source hydrodynamic model SFINCS on historical river floods at the global scale
Tarun Sadana, Jeroen C. J. H. Aerts, Dirk Eilander, Bruno Merz, Hans de Moel, Tim Busker, Veerle C. Bril, and Jens de Bruijn
Hydrol. Earth Syst. Sci., 30, 5491–5519, https://doi.org/10.5194/hess-30-5491-2026, 2026
We evaluated the open-source hydrodynamic model SFINCS using satellite data from 499 historical flood events across 96 countries. Our study shows that larger upstream river basins are modelled more accurately, while using observed river gauges and high-resolution elevation data can improve results. Our findings highlight the importance of large-scale validation with satellite data and sensitivity analyses to enhance future global flood hazard assessments and prediction accuracy.

Impacts of cascading check dams on sediment yield in the Middle Yellow River Basin: insights from 50 years of grid-cell-level simulation

Tue, 01 Sep 2026 15:21:51 +0200

Impacts of cascading check dams on sediment yield in the Middle Yellow River Basin: insights from 50 years of grid-cell-level simulation
Yanzhang Huang, Guangyao Gao, Lishan Ran, Yue Wang, and Mingguo Zheng
Hydrol. Earth Syst. Sci., 30, 5473–5490, https://doi.org/10.5194/hess-30-5473-2026, 2026
This study developed an integrative model combining sediment trapping of check dam networks with the Revised Universal Soil Loss Equation, index of connectivity, and sediment delivery ratio to reconstruct grid-scale sediment yield across the middle Yellow River Basin (1970–2020). The proposed model achieved about 20 % increase of simulation accuracy compared to ignoring check dam trapping. The sediment reduction contribution by check dams was quantified and controlling factors were detected.

Hydrological implications of vegetation-associated precipitation recycling during peak growing season over the Loess Plateau

Thu, 27 Aug 2026 15:21:51 +0200

Hydrological implications of vegetation-associated precipitation recycling during peak growing season over the Loess Plateau
Jiaxiang Deng, Quan Quan, Shuangcheng Tang, Hanbo Yang, and Xiaoyu Song
Hydrol. Earth Syst. Sci., 30, 5455–5472, https://doi.org/10.5194/hess-30-5455-2026, 2026
This study asks whether planting more vegetation on the Loess Plateau can bring enough extra rain to ease water shortages. By combining rainfall tracking with water balance analysis, we found that the added rain linked to vegetation is generally too small to make up for the extra water used by plant growth. Benefits are limited in sparsely vegetated areas and can turn negative where vegetation is dense, showing that restoration in dry regions has clear water limits.

Learning evaporative fraction with memory

Tue, 25 Aug 2026 15:21:51 +0200

Learning evaporative fraction with memory
Wenli Zhao, Alexander J. Winkler, Markus Reichstein, Rene Orth, and Pierre Gentine
Hydrol. Earth Syst. Sci., 30, 5373–5394, https://doi.org/10.5194/hess-30-5373-2026, 2026
We used explainable machine learning that incorporates memory effects to study how plants respond to weather and drought. Using data from 90 sites worldwide, we show that memory plays a key role in regulating plant water stress. Forests and savannas rely on longer past conditions than grasslands, reflecting differences in rooting depth and water use. These insights improve our ability to anticipate ecosystem vulnerability as droughts intensify.

Towards a semi-asynchronous method for hydrological modeling in climate change studies

Tue, 25 Aug 2026 15:21:51 +0200

Towards a semi-asynchronous method for hydrological modeling in climate change studies
Frédéric Talbot, Simon Ricard, Guillaume Drolet, Annie Poulin, Jean-Luc Martel, Richard Arsenault, and Jean-Daniel Sylvain
Hydrol. Earth Syst. Sci., 30, 5411–5453, https://doi.org/10.5194/hess-30-5411-2026, 2026
This study compares three hydrological modeling approaches for assessing climate change impacts on water systems. It evaluates the conventional method alongside a fully- and semi-asynchronous methods, which excels in capturing extreme events but faces challenges with event timing. The results highlight the potential of the semi-asynchronous method as an innovative and robust tool for hydrological modeling under climate change.

Modeling the long-term fate of injected CO2 in saline aquifers: An integrated framework coupling multiphase flow, dissolution, reaction, and ripening

Tue, 25 Aug 2026 15:21:51 +0200

Modeling the long-term fate of injected CO2 in saline aquifers: An integrated framework coupling multiphase flow, dissolution, reaction, and ripening
Ruiqi Chen, Wenjie Xu, Yunmin Chen, Qingping Li, Tianyuan Zheng, and Bo Guo
Hydrol. Earth Syst. Sci., 30, 5395–5409, https://doi.org/10.5194/hess-30-5395-2026, 2026
Geological carbon sequestration is a promising strategy to mitigate climate change. We developed an integrated numerical framework that combines injection, dissolution, mixing, reactions, and ripening. Key results indicate that dissolution restricts plume lateral migration and constitutes about 40 % of storage. Geochemical reactions contributes less than 1 % but promotes dissolution and long-term security. Over tens of millennia, ripening redistributes residual CO₂, forming a stable gas cap.

Process diagnostics of snowmelt runoff in global hydrological and land surface models – Part 1: A systematic evaluation across basins of increasing complexity

Fri, 21 Aug 2026 15:21:51 +0200

Process diagnostics of snowmelt runoff in global hydrological and land surface models – Part 1: A systematic evaluation across basins of increasing complexity
Xiangyong Lei, Haomei Lin, Kaihao Zheng, and Peirong Lin
Hydrol. Earth Syst. Sci., 30, 5343–5372, https://doi.org/10.5194/hess-30-5343-2026, 2026
Snowmelt runoff is a critical freshwater resource. This study assesses how well 15 large-scale models and runoff products simulate its volume, peak, and timing across 1455 snow-dominated basins, with special attention to model performance in increasingly complex basin environments. Our results reveal common biases and identify model types with relative strengths, providing guidance for water-resource planning and sustainable water management under global warming.

Technical note: A Water Analysis Trailer for Environmental Research (WATER)

Fri, 21 Aug 2026 15:21:51 +0200

Technical note: A Water Analysis Trailer for Environmental Research (WATER)
Aaron James Neill, David Windhorst, Philipp Kraft, Amir Sahraei, and Lutz Breuer
Hydrol. Earth Syst. Sci., 30, 5327–5342, https://doi.org/10.5194/hess-30-5327-2026, 2026
Understanding water flow paths and pollutant transport requires high-temporal-frequency measurements from multiple water sources distributed in space. A new mobile platform is presented that can autonomously measure stable water isotopes and water quality parameters for 72 water samples per day, currently acquirable from up to 11 sources. Proof-of-concept, value of the collected data, and considerations for future use are exemplified by deployment of the system to a small headwater catchment.

Lake Victoria to the Sudd Wetland: flood wave timing, connectivity and wetland buffering across the White Nile

Thu, 20 Aug 2026 15:21:51 +0200

Lake Victoria to the Sudd Wetland: flood wave timing, connectivity and wetland buffering across the White Nile
Douglas Mulangwa, Evet Naturinda, Charles Koboji, Benon T. Zaake, Emily Black, Hannah Cloke, and Elisabeth M. Stephens
Hydrol. Earth Syst. Sci., 30, 5297–5325, https://doi.org/10.5194/hess-30-5297-2026, 2026
This study traced how water moved from Lake Victoria to the Sudd wetlands to explain the prolonged flooding in South Sudan between 2019 and 2024. Using satellite observations, rainfall records, and lake and river measurements, we found that water takes about 17 months to travel through the system, much longer than previously assumed 5 months. The results show that lakes and wetlands can store and slowly release water over several years, helping improve flood forecasting and early warning.

Runoff thresholds, runoff generation mechanisms, and catchment characteristics: a global synthesis

Thu, 20 Aug 2026 15:21:51 +0200

Runoff thresholds, runoff generation mechanisms, and catchment characteristics: a global synthesis
Zhen Cui and Fuqiang Tian
Hydrol. Earth Syst. Sci., 30, 5281–5296, https://doi.org/10.5194/hess-30-5281-2026, 2026
This study synthesizes storm-runoff thresholds from 138 catchments worldwide to clarify why threshold behavior differs across environments. We show that runoff thresholds are often shaped by catchment wetness, storage, soils, geology, and flow-path connectivity, not rainfall alone. The results support a connectivity-based framework for interpreting runoff generation across diverse landscapes.

Year-round measurements of evaporation from northern latitude wetlands in Norway

Wed, 19 Aug 2026 15:21:51 +0200

Year-round measurements of evaporation from northern latitude wetlands in Norway
Astrid Vatne, Norbert Pirk, Kolbjørn Engeland, Ane V. Vollsnes, and Lena M. Tallaksen
Hydrol. Earth Syst. Sci., 30, 5245–5279, https://doi.org/10.5194/hess-30-5245-2026, 2026
Measurements of evaporation are important to understand how evaporation modifies the water balance of northern ecosystems. However, evaporation data in these regions are scarce. We explored a new dataset of evaporation measurements from four wetland sites in Norway and found that up to 30 % of the annual precipitation evaporate back to the atmosphere. Our results indicate that earlier snow melt-out and drier air can increase annual evaporation in the region.

Global escalation of more frequent and intense compound heatwave-extreme precipitation events

Wed, 19 Aug 2026 15:21:51 +0200

Global escalation of more frequent and intense compound heatwave-extreme precipitation events
Haoyu Jin, Moyang Liu, Ke Zhang, Xuan Yu, Xu Yang, Lijun Chao, Pengfei Zhang, and Guoyan Liu
Hydrol. Earth Syst. Sci., 30, 5229–5244, https://doi.org/10.5194/hess-30-5229-2026, 2026
Heatwaves and heavy rainfall are dangerous on their own. But when they occur in quick succession, extreme heat followed by intense rain, they can create even greater risks. Our findings show that compound heatwave-extreme precipitation events are becoming a distinct and worsening type of climate hazard. They can no longer be treated as isolated events. To build resilience, early warning systems, disaster planning, and adaptation strategies must now account for these compound risks.

Progressive groundwater decoupling may drive a shift toward shallower and faster terrestrial water cycling

Wed, 19 Aug 2026 15:21:51 +0200

Progressive groundwater decoupling may drive a shift toward shallower and faster terrestrial water cycling
Aoqi Sun, Wenjie Xu, Enze Ma, Hua Yuan, and Chen Yang
Hydrol. Earth Syst. Sci., 30, 5215–5227, https://doi.org/10.5194/hess-30-5215-2026, 2026
Groundwater is often viewed as a hidden reserve that supports evapotranspiration and streamflow during dry periods. We show that sustained warming and greening can weaken this buffering role. As groundwater levels decline, links between shallow and deeper stores reorganize, reducing older groundwater inputs to streams and evapotranspiration. Over time, water cycling shifts toward shallower, faster pathways, potentially lowering system resilience and predictability under long-term climate stress.

Hydrologic model parameter estimation in snow-dominated headwater catchments using multiple observation datasets

Mon, 17 Aug 2026 15:21:51 +0200

Hydrologic model parameter estimation in snow-dominated headwater catchments using multiple observation datasets
Lauren H. North, Adrienne M. Marshall, Glenn A. Tootle, Lisa Davis, Andy W. Wood, and Eric J. Anderson
Hydrol. Earth Syst. Sci., 30, 5195–5214, https://doi.org/10.5194/hess-30-5195-2026, 2026
We assessed the U.S. National Hydrologic Model's ability to simulate several components of the water cycle using multiple datasets of environmental variables. We find that the model's accuracy in streamflow simulation is positively and negatively impacted by the additional constraints, and more model parameters are identified as important. Our results inform operational hydrologic modeling by illuminating the complexities of using the continually expanding suite of data products.

Groundwater hysteresis increasingly decouples flowing network length from streamflow as snow shifts to rain

Fri, 14 Aug 2026 15:21:51 +0200

Groundwater hysteresis increasingly decouples flowing network length from streamflow as snow shifts to rain
Elijah N. Boardman, Mark S. Wigmosta, Nicole M. Fernandez, John A. Whiting, and Adrian A. Harpold
Hydrol. Earth Syst. Sci., 30, 5145–5171, https://doi.org/10.5194/hess-30-5145-2026, 2026
Distributed simulations and geochemical data indicate that groundwater hysteresis dampens the elasticity of flowing stream networks. This effect is expected to become more important as intense rainfall events replace gradual snowmelt in a warmer climate.

An argument for parsimony in differentiable hydrologic models

Fri, 14 Aug 2026 15:21:51 +0200

An argument for parsimony in differentiable hydrologic models
Sandeep Poudel and Scott Steinschneider
Hydrol. Earth Syst. Sci., 30, 5173–5193, https://doi.org/10.5194/hess-30-5173-2026, 2026
Hydrological models combining physics with AI are becoming popular for predicting river flow, but are often unnecessarily complex. We tested these models across US river basins and found three key results: simpler designs perform equally well, extensive input data adds little value, and time-varying parameters do not represent actual physical processes. These results challenge assumptions that complexity improves predictions or understanding, arguing instead for simpler hybrid model development.

Systematic overestimation of evapotranspiration over irrigated areas by an offline land surface model

Thu, 13 Aug 2026 15:21:51 +0200

Systematic overestimation of evapotranspiration over irrigated areas by an offline land surface model
Tanguy Lunel, Belén Martí, Aaron Boone, and Patrick Le Moigne
Hydrol. Earth Syst. Sci., 30, 5117–5143, https://doi.org/10.5194/hess-30-5117-2026, 2026
Modelling evapotranspiration is essential for understanding the water cycle. While irrigation is known to increase evapotranspiration, it is less known that it also modifies local weather, which can in turn partially reduce evapotranspiration. This latter phenomenon is overlooked in some land surface model configurations. This study investigates and quantifies the impact of this oversight, showing that land surface models overestimate evapotranspiration by about 25% for crops in irrigated areas.

A process-informed framework linking temperature-rainfall projections and urban flood modeling

Wed, 12 Aug 2026 15:21:51 +0200

A process-informed framework linking temperature-rainfall projections and urban flood modeling
Wenyue Zou, Ruidong Li, Daniel B. Wright, Jovan Blagojevic, Peter Molnar, Mohammad A. Hussain, Yue Zhu, Yongkun Li, Guangheng Ni, and Nadav Peleg
Hydrol. Earth Syst. Sci., 30, 5097–5116, https://doi.org/10.5194/hess-30-5097-2026, 2026
We present a framework using observed rainfall and temperature to generate realistic storms and simulate street-scale flooding for present and future climates. It integrates temperature-based rainfall scaling, storm-frequency estimation, and urban flood modeling, demonstrated in Beijing to assess changes in regional storm and flood depth, timing, and flow velocity. The workflow is data-light, physically grounded, and transferable worldwide.