Articles | Volume 25, issue 4
Hydrol. Earth Syst. Sci., 25, 2133–2158, 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article 20 Apr 2021
Research article | 20 Apr 2021
How catchment characteristics influence hydrological pathways and travel times in a boreal landscape
Elin Jutebring Sterte et al.
No articles found.
Conrad Jackisch, Sibylle K. Hassler, Tobias L. Hohenbrink, Theresa Blume, Hjalmar Laudon, Hilary McMillan, Patricia Saco, and Loes van Schaik
Hydrol. Earth Syst. Sci., 25, 5277–5285,
Stefan Willem Ploum, Anna Lupon, Jason A. Leach, Lenka Kuglerová, and Hjalmar Laudon
Hydrol. Earth Syst. Sci. Discuss.,
Preprint under review for HESSShort summary
Groundwater conveys carbon from the landscape to streams where some of the carbon is used by microbes in the stream. This process is very dynamic, and is not very well represented in carbon budgets. We combined groundwater inputs and microbial uptake to calculate carbon concentrations in streams. We found that at groundwater inputs there are large changes in stream carbon concentrations. Depending on the flow conditions (e.g. droughts or floods) this is attributed to groundwater or microbes.
Nataliia Kozii, Kersti Haahti, Pantana Tor-ngern, Jinshu Chi, Eliza Maher Hasselquist, Hjalmar Laudon, Samuli Launiainen, Ram Oren, Matthias Peichl, Jörgen Wallerman, and Niles J. Hasselquist
Hydrol. Earth Syst. Sci., 24, 2999–3014,Short summary
The hydrologic cycle is one of the greatest natural processes on Earth and strongly influences both regional and global climate as well as ecosystem functioning. Results from this study clearly show the central role trees play in regulating the water cycle of boreal catchments, implying that forest management impacts on stand structure as well as climate change effects on tree growth are likely to have large cascading effects on the way water moves through boreal forested landscapes.
Navid Ghajarnia, Georgia Destouni, Josefin Thorslund, Zahra Kalantari, Imenne Åhlén, Jesús A. Anaya-Acevedo, Juan F. Blanco-Libreros, Sonia Borja, Sergey Chalov, Aleksandra Chalova, Kwok P. Chun, Nicola Clerici, Amanda Desormeaux, Bethany B. Garfield, Pierre Girard, Olga Gorelits, Amy Hansen, Fernando Jaramillo, Jerker Jarsjö, Adnane Labbaci, John Livsey, Giorgos Maneas, Kathryn McCurley Pisarello, Sebastián Palomino-Ángel, Jan Pietroń, René M. Price, Victor H. Rivera-Monroy, Jorge Salgado, A. Britta K. Sannel, Samaneh Seifollahi-Aghmiuni, Ylva Sjöberg, Pavel Terskii, Guillaume Vigouroux, Lucia Licero-Villanueva, and David Zamora
Earth Syst. Sci. Data, 12, 1083–1100,Short summary
Hydroclimate and land-use conditions determine the dynamics of wetlands and their ecosystem services. However, knowledge and data for conditions and changes over entire wetlandscapes are scarce. This paper presents a novel database for 27 wetlandscapes around the world, combining survey-based local information and hydroclimatic and land-use datasets. The developed database can enhance our capacity to understand and manage critical wetland ecosystems and their services under global change.
Stefan W. Ploum, Hjalmar Laudon, Andrés Peralta-Tapia, and Lenka Kuglerová
Hydrol. Earth Syst. Sci., 24, 1709–1720,Short summary
Near-stream areas, or riparian zones, are important for the health of streams and rivers. If these areas are disturbed by forestry or other anthropogenic activity, the water quality and all life in streams may be at risk. We examined which riparian areas are particularly sensitive. We found that only a few wet areas bring most of the rainwater from the landscape to the stream, and they have a unique water quality. In order to maintain healthy streams and rivers, these areas should be protected.
Aaron Smith, Doerthe Tetzlaff, Hjalmar Laudon, Marco Maneta, and Chris Soulsby
Hydrol. Earth Syst. Sci., 23, 3319–3334,Short summary
We adapted and used a spatially distributed eco-hydrological model, EcH2O-iso, to temporally evaluate the influence of soil freeze–thaw dynamics on evaporation and transpiration fluxes in a northern Swedish catchment. We used multi-criterion calibration over multiple years and found an early-season influence of soil frost on transpiration water ages. This work provides a framework for quantifying the current and future interactions of soil water, evaporation, and transpiration.
Marcus Klaus, Erik Geibrink, Anders Jonsson, Ann-Kristin Bergström, David Bastviken, Hjalmar Laudon, Jonatan Klaminder, and Jan Karlsson
Biogeosciences, 15, 5575–5594,Short summary
Forest management is widely used to mitigate climate change. However, forest greenhouse gas (GHG) budgets neglect to consider that clear-cuts often release carbon and nitrogen into streams and lakes and may affect aquatic GHG emissions. Here, we show that such emissions remain unaffected by experimental boreal forest clear-cutting despite increased groundwater carbon dioxide and methane concentrations, highlighting that riparian zones or in-stream processes may have buffered clear-cut leachates.
Matthias Sprenger, Doerthe Tetzlaff, Jim Buttle, Hjalmar Laudon, and Chris Soulsby
Hydrol. Earth Syst. Sci., 22, 3965–3981,Short summary
We estimated water ages in the upper critical zone with a soil physical model (SWIS) and found that the age of water stored in the soil, as well as of water leaving the soil via evaporation, transpiration, or recharge, was younger the higher soil water storage (inverse storage effect). Travel times of transpiration and evaporation were different. We conceptualized the subsurface into fast and slow flow domains and the water was usually half as young in the fast as in the slow flow domain.
Martin Berggren, Marcus Klaus, Balathandayuthabani Panneer Selvam, Lena Ström, Hjalmar Laudon, Mats Jansson, and Jan Karlsson
Biogeosciences, 15, 457–470,Short summary
The quality of dissolved organic carbon (DOC), especially its color, is a defining feature of freshwater ecosystems. We found that colored DOC fractions are surprisingly resistant to natural degradation during water transit through many brown-water lakes. This is explained by the dominance of microbial processes that appear to selectively remove noncolored DOC. However, in lakes where sunlight degradation plays a relatively larger role, significant DOC bleaching occurs.
Fernando Jaramillo, Neil Cory, Berit Arheimer, Hjalmar Laudon, Ype van der Velde, Thomas B. Hasper, Claudia Teutschbein, and Johan Uddling
Hydrol. Earth Syst. Sci., 22, 567–580,Short summary
Which is the dominant effect on evapotranspiration in northern forests, an increase by recent forests expansion or a decrease by the water use response due to increasing CO2 concentrations? We determined the dominant effect during the period 1961–2012 in 65 Swedish basins. We used the Budyko framework to study the hydroclimatic movements in Budyko space. Our findings suggest that forest expansion is the dominant driver of long-term and large-scale evapotranspiration changes.
Pertti Ala-aho, Doerthe Tetzlaff, James P. McNamara, Hjalmar Laudon, and Chris Soulsby
Hydrol. Earth Syst. Sci., 21, 5089–5110,Short summary
We used the Spatially Distributed Tracer-Aided Rainfall-Runoff model (STARR) to simulate streamflows, stable water isotope ratios, snowpack dynamics, and water ages in three snow-influenced experimental catchments with exceptionally long and rich datasets. Our simulations reproduced the hydrological observations in all three catchments, suggested contrasting stream water age distributions between catchments, and demonstrated the importance of snow isotope processes in tracer-aided modelling.
Fredrik Lidman, Åsa Boily, Hjalmar Laudon, and Stephan J. Köhler
Biogeosciences, 14, 3001–3014,Short summary
The riparian zone is the narrow strip of land that lines a watercourse. This is the last soil that the groundwater is in contact with before it enters the stream and it therefore has a high impact on the water quality. In this paper we show that many elements occur in elevated concentrations in the peat-like riparian zone of boreal headwaters and that this also leads to elevated concentrations in the streams. Hence, understanding riparian soils is crucial for a sustainable management of streams.
Sina Muster, Kurt Roth, Moritz Langer, Stephan Lange, Fabio Cresto Aleina, Annett Bartsch, Anne Morgenstern, Guido Grosse, Benjamin Jones, A. Britta K. Sannel, Ylva Sjöberg, Frank Günther, Christian Andresen, Alexandra Veremeeva, Prajna R. Lindgren, Frédéric Bouchard, Mark J. Lara, Daniel Fortier, Simon Charbonneau, Tarmo A. Virtanen, Gustaf Hugelius, Juri Palmtag, Matthias B. Siewert, William J. Riley, Charles D. Koven, and Julia Boike
Earth Syst. Sci. Data, 9, 317–348,Short summary
Waterbodies are abundant in Arctic permafrost lowlands. Most waterbodies are ponds with a surface area smaller than 100 x 100 m. The Permafrost Region Pond and Lake Database (PeRL) for the first time maps ponds as small as 10 x 10 m. PeRL maps can be used to document changes both by comparing them to historical and future imagery. The distribution of waterbodies in the Arctic is important to know in order to manage resources in the Arctic and to improve climate predictions in the Arctic.
Tobias Lindborg, Johan Rydberg, Mats Tröjbom, Sten Berglund, Emma Johansson, Anders Löfgren, Peter Saetre, Sara Nordén, Gustav Sohlenius, Eva Andersson, Johannes Petrone, Micke Borgiel, Ulrik Kautsky, and Hjalmar Laudon
Earth Syst. Sci. Data, 8, 439–459,Short summary
This paper presents a biogeochemical and ecological data set from the Kangerlussuaq region, western Greenland. The data set is used to conceptualize and model terrestrial and limnic ecosystems as well as the land–lake linkage. Both biotic and abiotic data is presented and will be used for biogeochemical mass-balance and transport calculations. The data set constitutes an important source in order to understand and describe accumulation and flow of matter within periglacial landscapes.
Stephen Oni, Martyn Futter, Jose Ledesma, Claudia Teutschbein, Jim Buttle, and Hjalmar Laudon
Hydrol. Earth Syst. Sci., 20, 2811–2825,Short summary
This paper presents an important framework to improve hydrologic projections in cold regions. Hydrologic modelling/projections are often based on model calibration to long-term data. Here we used dry and wet years as a proxy to quantify uncertainty in projecting hydrologic extremes. We showed that projections based on long-term data could underestimate runoff by up to 35% in boreal regions. We believe the hydrologic modelling community will benefit from new insights derived from this study.
J. Schelker, R. Sponseller, E. Ring, L. Högbom, S. Löfgren, and H. Laudon
Biogeosciences, 13, 1–12,Short summary
The scientific question that is addressed in this study is how forest disturbance affects organic and inorganic nitrogen export from a boreal landscape. The key findings are that the mobilization of inorganic nitrogen from the terrestrial environment to streams increased strongly as a response to harvesting, but the stream network removed a major fraction of this load before it reached the outlet, while organic nitrogen was not removed and transported downstream.
M. Haei and H. Laudon
Revised manuscript not accepted
M. Fritz, B. N. Deshpande, F. Bouchard, E. Högström, J. Malenfant-Lepage, A. Morgenstern, A. Nieuwendam, M. Oliva, M. Paquette, A. C. A. Rudy, M. B. Siewert, Y. Sjöberg, and S. Weege
The Cryosphere, 9, 1715–1720,Short summary
This is a contribution about the future of permafrost research to the 3rd International Conference on Arctic Research Planning 2015 (ICARP III). We summarize the top five research questions for the next decade of permafrost science from the perspective of early career researchers (ECRs). We highlight the pathways and structural preconditions to address these research priorities. This manuscript is an outcome of a community consultation conducted for and by ECRs on a global level.
A. A. Harpold, J. A. Marshall, S. W. Lyon, T. B. Barnhart, B. A. Fisher, M. Donovan, K. M. Brubaker, C. J. Crosby, N. F. Glenn, C. L. Glennie, P. B. Kirchner, N. Lam, K. D. Mankoff, J. L. McCreight, N. P. Molotch, K. N. Musselman, J. Pelletier, T. Russo, H. Sangireddy, Y. Sjöberg, T. Swetnam, and N. West
Hydrol. Earth Syst. Sci., 19, 2881–2897,Short summary
This review's objective is to demonstrate the transformative potential of lidar by critically assessing both challenges and opportunities for transdisciplinary lidar applications in geomorphology, hydrology, and ecology. We find that using lidar to its full potential will require numerous advances, including more powerful open-source processing tools, new lidar acquisition technologies, and improved integration with physically based models and complementary observations.
F. I. Leith, K. J. Dinsmore, M. B. Wallin, M. F. Billett, K. V. Heal, H. Laudon, M. G. Öquist, and K. Bishop
Biogeosciences, 12, 1881–1892,Short summary
Carbon dioxide transport between the terrestrial and aquatic systems was dominated by export from the near-stream riparian zone. Over the year, riparian export was highest during autumn storms and the spring snowmelt event. This resulted in high downstream export during these periods with vertical evasion from the stream surface accounting for 60% of the total stream water export, highlighting the importance of evasion to carbon export via the aquatic conduit.
Y. Sjöberg, P. Marklund, R. Pettersson, and S. W. Lyon
The Cryosphere, 9, 465–478,Short summary
Permafrost peatlands are hydrological and biogeochemical hotspots in discontinuous permafrost areas. We estimate the depths to the permafrost table surface and base across a peatland in northern Sweden using ground penetrating radar and electrical resistivity tomography. Seasonal frost tables, taliks, and the permafrost base could be detected. The results highlight the added value of combining techniques for assessing distributions of permafrost in the rapidly changing sporadic permafrost zone.
H. Zarei, A. M. Akhondali, H. Mohammadzadeh, F. Radmanesh, and H. Laudon
Hydrol. Earth Syst. Sci. Discuss.,
Manuscript not accepted for further review
A. M. Ågren, I. Buffam, D. M. Cooper, T. Tiwari, C. D. Evans, and H. Laudon
Biogeosciences, 11, 1199–1213,
E. Bosson, T. Lindborg, S. Berglund, L.-G. Gustafsson, J.-O. Selroos, H. Laudon, L. L. Claesson, and G. Destouni
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript not accepted
J. L. J. Ledesma, T. Grabs, M. N. Futter, K. H. Bishop, H. Laudon, and S. J. Köhler
Biogeosciences, 10, 3849–3868,
S. K. Oni, M. N. Futter, K. Bishop, S. J. Köhler, M. Ottosson-Löfvenius, and H. Laudon
Biogeosciences, 10, 2315–2330,
Related subject area
Subject: Catchment hydrology | Techniques and Approaches: Modelling approachesBenchmarking data-driven rainfall–runoff models in Great Britain: a comparison of long short-term memory (LSTM)-based models with four lumped conceptual modelsNumerical daemons of hydrological models are summoned by extreme precipitationHow is Baseflow Index (BFI) impacted by water resource management practices?Technical note: RAT – a robustness assessment test for calibrated and uncalibrated hydrological modelsReduction of vegetation-accessible water storage capacity after deforestation affects catchment travel time distributions and increases young water fractions in a headwater catchmentCombining split-sample testing and hidden Markov modelling to assess the robustness of hydrological modelsHydrologically informed machine learning for rainfall–runoff modelling: towards distributed modellingDevelopment and evaluation of 0.05° terrestrial water storage estimates using Community Atmosphere Biosphere Land Exchange (CABLE) land surface model and assimilation of GRACE dataConditioning ensemble streamflow prediction with the North Atlantic Oscillation improves skill at longer lead timesTechnical note: Hydrology modelling R packages – a unified analysis of models and practicalities from a user perspectiveA new fractal-theory-based criterion for hydrological model calibrationThe value of water isotope data on improving process understanding in a glacierized catchment on the Tibetan PlateauMachine learning deciphers CO2 sequestration and subsurface flowpaths from stream chemistryFuture changes in annual, seasonal and monthly runoff signatures in contrasting Alpine catchments in AustriaUsing hydrologic landscape classification and climatic time series to assess hydrologic vulnerability of the western U.S. to climateEvaluation of random forests for short-term daily streamflow forecasting in rainfall- and snowmelt-driven watershedsPerformance of automated methods for flash flood inundation mapping: a comparison of a digital terrain model (DTM) filling and two hydrodynamic methodsA novel method for cold-region streamflow hydrograph separation using GRACE satellite observationsA Bayesian approach to understanding the key factors influencing temporal variability in stream water quality – a case study in the Great Barrier Reef catchmentsProjected changes in Rhine River flood seasonality under global warmingTechnical note: Diagnostic efficiency – specific evaluation of model performanceRainfall–runoff prediction at multiple timescales with a single Long Short-Term Memory networkUser-oriented hydrological indices for early warning systems with validation using post-event surveys: flood case studies in the Central Apennine DistrictIn-stream Escherichia Coli Modeling Using high-temporal-resolution data with deep learning and process-based modelsSpace–time variability in soil moisture droughts in the Himalayan regionA multi-sourced assessment of the spatiotemporal dynamics of soil moisture in the MARINE flash flood modelClimate change impacts model parameter sensitivity – implications for calibration strategy and model diagnostic evaluationImpact of karst areas on runoff generation, lateral flow and interbasin groundwater flow at the storm-event timescaleTriple oxygen isotope systematics of evaporation and mixing processes in a dynamic desert lake systemIrrigation, damming, and streamflow fluctuations of the Yellow RiverBehind the scenes of streamflow model performanceLearning from satellite observations: increased understanding of catchment processes through stepwise model improvementDiagnosis toward predicting mean annual runoff in ungauged basinsPatterns and dynamics of dissolved organic carbon exports from a riparian zone of a temperate, forested catchmentThe era of infiltrationA time-varying parameter estimation approach using split-sample calibration based on dynamic programmingA history of TOPMODELProgressive water deficits during multiyear droughts in basins with long hydrological memory in ChileA comparison of catchment travel times and storage deduced from deuterium and tritium tracers using StorAge Selection functionsBending of the concentration discharge relationship can inform about in-stream nitrate removalThe role and value of distributed precipitation data in hydrological modelsFlood spatial coherence, triggers, and performance in hydrological simulations: large-sample evaluation of four streamflow-calibrated modelsEffects of spatial resolution of terrain models on modelled discharge and soil loss in Oaxaca, MexicoFlexible vector-based spatial configurations in land modelsTwo-stage variational mode decomposition and support vector regression for streamflow forecastingPredicting probabilities of streamflow intermittency across a temperate mesoscale catchmentImportance of the informative content in the study area when regionalising rainfall-runoff model parameters: the role of nested catchments and gauging station densityWhich rainfall score is more informative about the performance in river discharge simulation? A comprehensive assessment on 1318 basins over EuropeAssimilation of Soil Moisture and Ocean Salinity (SMOS) brightness temperature into a large-scale distributed conceptual hydrological model to improve soil moisture predictions: the Murray–Darling basin in Australia as a test caseFrequency and magnitude variability of Yalu River flooding: numerical analyses for the last 1000 years
Thomas Lees, Marcus Buechel, Bailey Anderson, Louise Slater, Steven Reece, Gemma Coxon, and Simon J. Dadson
Hydrol. Earth Syst. Sci., 25, 5517–5534,Short summary
We used deep learning (DL) models to simulate the amount of water moving through a river channel (discharge) based on the rainfall, temperature and potential evaporation in the previous days. We tested the DL models on catchments across Great Britain finding that the model can accurately simulate hydrological systems across a variety of catchment conditions. Ultimately, the model struggled most in areas where there is chalky bedrock and where human influence on the catchment is large.
Peter T. La Follette, Adriaan J. Teuling, Nans Addor, Martyn Clark, Koen Jansen, and Lieke A. Melsen
Hydrol. Earth Syst. Sci., 25, 5425–5446,Short summary
Hydrological models are useful tools that allow us to predict distributions and movement of water. A variety of numerical methods are used by these models. We demonstrate which numerical methods yield large errors when subject to extreme precipitation. As the climate is changing such that extreme precipitation is more common, we find that some numerical methods are better suited for use in hydrological models. Also, we find that many current hydrological models use relatively inaccurate methods.
John P. Bloomfield, Mengyi Gong, Benjamin P. Marchant, Gemma Coxon, and Nans Addor
Hydrol. Earth Syst. Sci., 25, 5355–5379,Short summary
Groundwater provides flow, known as baseflow, to surface streams and rivers. It is important as it sustains the flow of many rivers at times of water stress. However, it may be affected by water management practices. Statistical models have been used to show that abstraction of groundwater may influence baseflow. Consequently, it is recommended that information on groundwater abstraction is included in future assessments and predictions of baseflow.
Pierre Nicolle, Vazken Andréassian, Paul Royer-Gaspard, Charles Perrin, Guillaume Thirel, Laurent Coron, and Léonard Santos
Hydrol. Earth Syst. Sci., 25, 5013–5027,Short summary
In this note, a new method (RAT) is proposed to assess the robustness of hydrological models. The RAT method is particularly interesting because it does not require multiple calibrations (it is therefore applicable to uncalibrated models), and it can be used to determine whether a hydrological model may be safely used for climate change impact studies. Success at the robustness assessment test is a necessary (but not sufficient) condition of model robustness.
Markus Hrachowitz, Michael Stockinger, Miriam Coenders-Gerrits, Ruud van der Ent, Heye Bogena, Andreas Lücke, and Christine Stumpp
Hydrol. Earth Syst. Sci., 25, 4887–4915,Short summary
Deforestation affects how catchments store and release water. Here we found that deforestation in the study catchment led to a 20 % increase in mean runoff, while reducing the vegetation-accessible water storage from about 258 to 101 mm. As a consequence, fractions of young water in the stream increased by up to 25 % during wet periods. This implies that water and solutes are more rapidly routed to the stream, which can, after contamination, lead to increased contaminant peak concentrations.
Etienne Guilpart, Vahid Espanmanesh, Amaury Tilmant, and François Anctil
Hydrol. Earth Syst. Sci., 25, 4611–4629,Short summary
The stationary assumption in hydrology has become obsolete because of climate changes. In that context, it is crucial to assess the performance of a hydrologic model over a wide range of climates and their corresponding hydrologic conditions. In this paper, numerous, contrasted, climate sequences identified by a hidden Markov model (HMM) are used in a differential split-sample testing framework to assess the robustness of a hydrologic model. We illustrate the method on the Senegal River.
Herath Mudiyanselage Viraj Vidura Herath, Jayashree Chadalawada, and Vladan Babovic
Hydrol. Earth Syst. Sci., 25, 4373–4401,Short summary
Existing hydrological knowledge has been integrated with genetic programming based on a machine learning algorithm (MIKA-SHA) to induce readily interpretable distributed rainfall–runoff models. At present, the model building components of two flexible modelling frameworks (FUSE and SUPERFLEX) represent the elements of hydrological knowledge. The proposed toolkit captures spatial variabilities and automatically induces semi-distributed rainfall–runoff models without any explicit user selections.
Natthachet Tangdamrongsub, Michael F. Jasinski, and Peter J. Shellito
Hydrol. Earth Syst. Sci., 25, 4185–4208,Short summary
Accurate estimation of terrestrial water storage (TWS) is essential for reliable water resource assessments. TWS can be estimated from the Community Atmosphere–Biosphere Land Exchange model (CABLE), but the resolution is limited to 0.5°. We reconfigure CABLE to improve TWS spatial details from 0.5° to 0.05°. GRACE satellite data are assimilated into CABLE to improve TWS accuracy. Our workflow relies only on publicly accessible data, allowing reproduction of 0.05° TWS in any region.
Seán Donegan, Conor Murphy, Shaun Harrigan, Ciaran Broderick, Dáire Foran Quinn, Saeed Golian, Jeff Knight, Tom Matthews, Christel Prudhomme, Adam A. Scaife, Nicky Stringer, and Robert L. Wilby
Hydrol. Earth Syst. Sci., 25, 4159–4183,Short summary
We benchmarked the skill of ensemble streamflow prediction (ESP) for a diverse sample of 46 Irish catchments. We found that ESP is skilful in the majority of catchments up to several months ahead. However, the level of skill was strongly dependent on lead time, initialisation month, and individual catchment location and storage properties. We also conditioned ESP with the winter North Atlantic Oscillation and show that improvements in forecast skill, reliability, and discrimination are possible.
Paul C. Astagneau, Guillaume Thirel, Olivier Delaigue, Joseph H. A. Guillaume, Juraj Parajka, Claudia C. Brauer, Alberto Viglione, Wouter Buytaert, and Keith J. Beven
Hydrol. Earth Syst. Sci., 25, 3937–3973,Short summary
The R programming language has become an important tool for many applications in hydrology. In this study, we provide an analysis of some of the R tools providing hydrological models. In total, two aspects are uniformly investigated, namely the conceptualisation of the models and the practicality of their implementation for end-users. These comparisons aim at easing the choice of R tools for users and at improving their usability for hydrology modelling to support more transferable research.
Zhixu Bai, Yao Wu, Di Ma, and Yue-Ping Xu
Hydrol. Earth Syst. Sci., 25, 3675–3690,Short summary
To test our hypothesis that the fractal dimensions of streamflow series can be used to improve the calibration of hydrological models, we designed the E–RD efficiency ratio of fractal dimensions strategy and examined its usability in the calibration of lumped models. The results reveal that, in most aspects, introducing RD into model calibration makes the simulation of streamflow components more reasonable. Also, pursuing a better RD during calibration leads to only a minor decrease in E.
Yi Nan, Lide Tian, Zhihua He, Fuqiang Tian, and Lili Shao
Hydrol. Earth Syst. Sci., 25, 3653–3673,Short summary
This study integrated a water isotope module into the hydrological model THREW. The isotope-aided model was subsequently applied for process understanding in the glacierized watershed of Karuxung river on the Tibetan Plateau. The model was used to quantify the contribution of runoff component and estimate the water travel time in the catchment. Model uncertainties were significantly constrained by using additional isotopic data, improving the process understanding in the catchment.
Andrew R. Shaughnessy, Xin Gu, Tao Wen, and Susan L. Brantley
Hydrol. Earth Syst. Sci., 25, 3397–3409,Short summary
It is often difficult to determine the sources of solutes in streams and how much each source contributes. We developed a new method of unmixing stream chemistry via machine learning. We found that sulfate in three watersheds is related to groundwater flowpaths. Our results emphasize that acid rain reduces a watershed's capacity to remove CO2 from the atmosphere, a key geological control on climate. Our method will help scientists unmix stream chemistry in watersheds where sources are unknown.
Sarah Hanus, Markus Hrachowitz, Harry Zekollari, Gerrit Schoups, Miren Vizcaino, and Roland Kaitna
Hydrol. Earth Syst. Sci., 25, 3429–3453,Short summary
This study investigates the effects of climate change on runoff patterns in six Alpine catchments in Austria at the end of the 21st century. Our results indicate a substantial shift to earlier occurrences in annual maximum and minimum flows in high-elevation catchments. Magnitudes of annual extremes are projected to increase under a moderate emission scenario in all catchments. Changes are generally more pronounced for high-elevation catchments.
Chas E. Jones Jr., Scott G. Leibowitz, Keith A. Sawicz, Randy L. Comeleo, Laurel E. Stratton, Philip E. Morefield, and Christopher P. Weaver
Hydrol. Earth Syst. Sci., 25, 3179–3206,Short summary
Our research assesses the hydrologic vulnerability of the western U.S. to climate by classifying the landscape based on its physical and climatic characteristics and analyzing climate data. We also apply the approach to examine the vulnerabilities of case studies in the ski and wine industries. We show that the west and its ski areas are vulnerable to changes in snow, while vineyard vulnerability varies. This allows us to consider climatic impacts across landscapes, industries, and stakeholders.
Leo Triet Pham, Lifeng Luo, and Andrew Finley
Hydrol. Earth Syst. Sci., 25, 2997–3015,Short summary
Model evaluation metrics suggest that RF performs better in snowmelt-driven watersheds. The largest improvements in forecasts compared to benchmark models are found among rainfall-driven watersheds. RF performance deteriorates with increases in catchment slope and soil sandiness. We note disagreement between two popular measures of RF variable importance and recommend jointly considering these measures with the physical processes under study.
Nabil Hocini, Olivier Payrastre, François Bourgin, Eric Gaume, Philippe Davy, Dimitri Lague, Lea Poinsignon, and Frederic Pons
Hydrol. Earth Syst. Sci., 25, 2979–2995,Short summary
Efficient flood mapping methods are needed for large-scale, comprehensive identification of flash flood inundation hazards caused by small upstream rivers. An evaluation of three automated mapping approaches of increasing complexity, i.e., a digital terrain model (DTM) filling and two 1D–2D hydrodynamic approaches, is presented based on three major flash floods in southeastern France. The results illustrate some limits of the DTM filling method and the value of using a 2D hydrodynamic approach.
Shusen Wang, Junhua Li, and Hazen A. J. Russell
Hydrol. Earth Syst. Sci., 25, 2649–2662,Short summary
Separating river flow into baseflow and surface runoff provides useful information for hydrology and climate studies, but traditional methods have critical limitations in the lack of physics, identifying snowmelt runoff and watershed size. This study developed a novel model using the GRACE satellite observations to address these limitations. It also includes estimates for watershed hydraulic conductivity and drainable water storage, which help assess aquifer properties and water resources.
Shuci Liu, Dongryeol Ryu, J. Angus Webb, Anna Lintern, Danlu Guo, David Waters, and Andrew W. Western
Hydrol. Earth Syst. Sci., 25, 2663–2683,Short summary
Riverine water quality can change markedly at one particular location. This study developed predictive models to represent the temporal variation in stream water quality across the Great Barrier Reef catchments, Australia. The model structures were informed by a data-driven approach, which is useful for identifying important factors determining temporal changes in water quality and, in turn, providing critical information for developing management strategies.
Erwin Rottler, Axel Bronstert, Gerd Bürger, and Oldrich Rakovec
Hydrol. Earth Syst. Sci., 25, 2353–2371,Short summary
The mesoscale hydrological model (mHM) forced with an ensemble of climate projection scenarios was used to assess potential future changes in flood seasonality in the Rhine River basin. Results indicate that future changes in flood characteristics are controlled by increases in precipitation sums and diminishing snowpacks. The decreases in snowmelt can counterbalance increasing precipitation, resulting in only small and transient changes in streamflow maxima.
Robin Schwemmle, Dominic Demand, and Markus Weiler
Hydrol. Earth Syst. Sci., 25, 2187–2198,Short summary
A better understanding of the reasons why model performance is unsatisfying represents a crucial part for meaningful model evaluation. We propose the novel diagnostic efficiency (DE) measure and diagnostic polar plots. The proposed evaluation approach provides a diagnostic tool for model developers and model users and facilitates interpretation of model performance.
Martin Gauch, Frederik Kratzert, Daniel Klotz, Grey Nearing, Jimmy Lin, and Sepp Hochreiter
Hydrol. Earth Syst. Sci., 25, 2045–2062,Short summary
We present multi-timescale Short-Term Memory (MTS-LSTM), a machine learning approach that predicts discharge at multiple timescales within one model. MTS-LSTM is significantly more accurate than the US National Water Model and computationally more efficient than an individual LSTM model per timescale. Further, MTS-LSTM can process different input variables at different timescales, which is important as the lead time of meteorological forecasts often depends on their temporal resolution.
Annalina Lombardi, Valentina Colaiuda, Marco Verdecchia, and Barbara Tomassetti
Hydrol. Earth Syst. Sci., 25, 1969–1992,Short summary
The paper presents a modelling approach for the assessment of extremes in the hydrological cycle at a multi-catchment scale. It describes two new hydrological stress indices, innovative instruments that could be used by Civil Protection operators, for flood mapping in early warning systems. The main advantage in using the proposed indices is the possibility of displaying hydrological-stress information over any geographical domain.
Ather Abbas, Sangsoo Baek, Norbert Silvera, Bounsamay Soulileuth, Yakov Pachepsky, Olivier Ribolzi, Laurie Boithias, and Kyung Hwa Cho
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript accepted for HESSShort summary
Correct estimation of fecal indicator bacteria in surface waters is critical for public health. Process driven models and recently data-driven models have been applied for water quality modeling however a systematic comparison for simulation of E. coli is missing in literature. We compared the performance of a process driven (HSPF) and a data-driven (LSTM) model for E. coli simulation. We show that LSTM can be an alternative to process driven models for estimation of E. coli in surface waters.
Santosh Nepal, Saurav Pradhananga, Narayan Kumar Shrestha, Sven Kralisch, Jayandra P. Shrestha, and Manfred Fink
Hydrol. Earth Syst. Sci., 25, 1761–1783,Short summary
This paper examines soil moisture drought in the central Himalayan region by applying a process-based hydrological model. Our results suggest that both the occurrence and severity of droughts have increased over the last 3 decades, especially in the winter and pre-monsoon seasons. The insights provided into the frequency, spatial coverage, and severity of the drought conditions can provide valuable inputs towards improved management of water resources and greater agricultural productivity.
Judith Eeckman, Hélène Roux, Audrey Douinot, Bertrand Bonan, and Clément Albergel
Hydrol. Earth Syst. Sci., 25, 1425–1446,Short summary
The risk of flash flood is of growing importance for populations, particularly in the Mediterranean area in the context of a changing climate. The representation of soil processes in models is a key factor for flash flood simulation. The importance of the various methods for soil moisture estimation are highlighted in this work. Local measurements from the field as well as data derived from satellite imagery can be used to assess the performance of model outputs.
Lieke Anna Melsen and Björn Guse
Hydrol. Earth Syst. Sci., 25, 1307–1332,Short summary
Certain hydrological processes become more or less relevant when the climate changes. This should also be visible in the models that are used for long-term predictions of river flow as a consequence of climate change. We investigated this using three different models. The change in relevance should be reflected in how the parameters of the models are determined. In the different models, different processes become more relevant in the future: they disagree with each other.
Martin Le Mesnil, Roger Moussa, Jean-Baptiste Charlier, and Yvan Caballero
Hydrol. Earth Syst. Sci., 25, 1259–1282,Short summary
We present an innovative approach consisting of the statistical analysis and comparison of 15 hydrological descriptors, characterizing catchment response to rainfall events. The distribution of these descriptors is analysed according to the occurrence of karst areas inside 108 catchments. It shows that karst impacts on storm events mainly result in river losses and that interbasin groundwater flows can represent a significant part of the catchment water budget ah the event timescale.
Claudia Voigt, Daniel Herwartz, Cristina Dorador, and Michael Staubwasser
Hydrol. Earth Syst. Sci., 25, 1211–1228,Short summary
Evaporation trends in the stable isotope composition (18O/16O, 17O/16O, 2H/1H) of throughflow ponds in a hydrologically complex and seasonally dynamic lake system can be reliably predicted by the classic Craig–Gordon isotope evaporation model. We demonstrate that the novel 17O-excess parameter is capable of resolving different types of evaporation with and without recharge and of identifying mixing processes that cannot be resolved using the classic δ2H–δ18O system alone.
Zun Yin, Catherine Ottlé, Philippe Ciais, Feng Zhou, Xuhui Wang, Polcher Jan, Patrice Dumas, Shushi Peng, Laurent Li, Xudong Zhou, Yan Bo, Yi Xi, and Shilong Piao
Hydrol. Earth Syst. Sci., 25, 1133–1150,Short summary
We improved the irrigation module in a land surface model ORCHIDEE and developed a dam operation model with the aim to investigate how irrigation and dams affect the streamflow fluctuations of the Yellow River. Results show that irrigation mainly reduces the annual river flow. The dam operation, however, mainly affects streamflow variation. By considering two generic operation rules, flood control and base flow guarantee, our dam model can sustainably improve the simulation accuracy.
Laurène J. E. Bouaziz, Fabrizio Fenicia, Guillaume Thirel, Tanja de Boer-Euser, Joost Buitink, Claudia C. Brauer, Jan De Niel, Benjamin J. Dewals, Gilles Drogue, Benjamin Grelier, Lieke A. Melsen, Sotirios Moustakas, Jiri Nossent, Fernando Pereira, Eric Sprokkereef, Jasper Stam, Albrecht H. Weerts, Patrick Willems, Hubert H. G. Savenije, and Markus Hrachowitz
Hydrol. Earth Syst. Sci., 25, 1069–1095,Short summary
We quantify the differences in internal states and fluxes of 12 process-based models with similar streamflow performance and assess their plausibility using remotely sensed estimates of evaporation, snow cover, soil moisture and total storage anomalies. The dissimilarities in internal process representation imply that these models cannot all simultaneously be close to reality. Therefore, we invite modelers to evaluate their models using multiple variables and to rely on multi-model studies.
Petra Hulsman, Hubert H. G. Savenije, and Markus Hrachowitz
Hydrol. Earth Syst. Sci., 25, 957–982,Short summary
Satellite observations have increasingly been used for model calibration, while model structural developments largely rely on discharge data. For large river basins, this often results in poor representations of system internal processes. This study explores the combined use of satellite-based evaporation and total water storage data for model structural improvement and spatial–temporal model calibration for a large, semi-arid and data-scarce river system.
Yuan Gao, Lili Yao, Ni-Bin Chang, and Dingbao Wang
Hydrol. Earth Syst. Sci., 25, 945–956,Short summary
Mean annual runoff prediction is of great interest but still poses a challenge in ungauged basins. The purpose of this study is to diagnose the data requirement for predicting mean annual runoff in ungauged basins based on a water balance model, in which the effects of climate variability are explicitly represented. The performance of predicting mean annual runoff can be improved by employing better estimation of soil water storage capacity including the effects of soil, topography, and bedrock.
Benedikt J. Werner, Oliver J. Lechtenfeld, Andreas Musolff, Gerrit H. de Rooij, Jie Yang, Ralf Gründling, Ulrike Werban, and Jan H. Fleckenstein
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript accepted for HESSShort summary
Export of dissolved organic carbon (DOC) from riparian zones (RZs) is an important, yet poorly understood component of the catchment carbon budget. This study chemically and spatially classifies DOC source zones within a RZ of a small catchment to assess DOC export patterns. Results highlight that DOC export from only a small fraction of the RZ with distinct DOC composition dominates overall DOC export. The application of a spatial, topographic proxy can be used to improve DOC export models.
Hydrol. Earth Syst. Sci., 25, 851–866,Short summary
Inspired by a quotation from Howard Cook in 1946, this paper traces the evolution of the infiltration theory of runoff from the work of Robert Horton and LeRoy Sherman in the 1930s to the early digital computer models of the 1970s and 1980s. Reconsideration of the perceptual model for many catchments, partly as a result of the greater appreciation of the contribution of subsurface flows to the hydrograph indicated by tracer studies, suggests a reconsideration of hydrological nomenclature.
Xiaojing Zhang and Pan Liu
Hydrol. Earth Syst. Sci., 25, 711–733,Short summary
Rainfall–runoff models are useful tools for streamflow simulation. However, efforts are needed to investigate how their parameters vary in response to climate changes and human activities. Thus, this study proposes a new method for estimating time-varying parameters, by considering both simulation accuracy and parameter continuity. The results show the proposed method is effective for identifying temporal variations of parameters and can simultaneously provide good streamflow simulation.
Keith J. Beven, Mike J. Kirkby, Jim E. Freer, and Rob Lamb
Hydrol. Earth Syst. Sci., 25, 527–549,Short summary
The theory that forms the basis of TOPMODEL was first outlined by Mike Kirkby some 45 years ago. This paper recalls some of the early developments: the rejection of the first journal paper, the early days of digital terrain analysis, model calibration and validation, the various criticisms of the simplifying assumptions, and the relaxation of those assumptions in the dynamic forms of TOPMODEL, and it considers what we might do now with the benefit of hindsight.
Camila Alvarez-Garreton, Juan Pablo Boisier, René Garreaud, Jan Seibert, and Marc Vis
Hydrol. Earth Syst. Sci., 25, 429–446,Short summary
The megadrought experienced in Chile (2010–2020) has led to larger than expected water deficits. By analysing 106 basins with snow-/rainfall regimes, we relate such intensification with the hydrological memory of the basins, explained by snow and groundwater. Snow-dominated basins have larger memory and thus accumulate the effect of persistent precipitation deficits more strongly than pluvial basins. This notably affects central Chile, a water-limited region where most of the population lives.
Nicolas Björn Rodriguez, Laurent Pfister, Erwin Zehe, and Julian Klaus
Hydrol. Earth Syst. Sci., 25, 401–428,Short summary
Different parts of water have often been used as tracers to determine the age of water in streams. The stable tracers, such as deuterium, are thought to be unable to reveal old water compared to the radioactive tracer called tritium. We used both tracers, measured in precipitation and in a stream in Luxembourg, to show that this is not necessarily true. It is, in fact, advantageous to use the two tracers together, and we recommend systematically using tritium in future studies.
Joni Dehaspe, Fanny Sarrazin, Rohini Kumar, Jan H. Fleckenstein, and Andreas Musolff
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript accepted for HESSShort summary
Increased nitrate concentrations in surface waters can compromise river ecosystem health. As riverine nitrate uptake is hard to measure, we explore how low frequency nitrate concentration and discharge observations (that are widely available) can help to identify (in)efficient uptake in river networks. We find that channel geometry and water velocity rather than the biological uptake capacity dominate the nitrate-discharge pattern at the outlet. The former can be used to predict uptake.
Ralf Loritz, Markus Hrachowitz, Malte Neuper, and Erwin Zehe
Hydrol. Earth Syst. Sci., 25, 147–167,Short summary
This study investigates the role and value of distributed rainfall in the runoff generation of a mesoscale catchment. We compare the performance of different hydrological models at different periods and show that a distributed model driven by distributed rainfall yields improved performances only during certain periods. We then step beyond this finding and develop a spatially adaptive model that is capable of dynamically adjusting its spatial model structure in time.
Manuela I. Brunner, Lieke A. Melsen, Andrew W. Wood, Oldrich Rakovec, Naoki Mizukami, Wouter J. M. Knoben, and Martyn P. Clark
Hydrol. Earth Syst. Sci., 25, 105–119,Short summary
Assessments of current, local, and regional flood hazards and their future changes often involve the use of hydrologic models. A reliable model ideally reproduces both local flood characteristics and regional aspects of flooding. In this paper we investigate how such characteristics are represented by hydrologic models. Our results show that both the modeling of local and regional flood characteristics are challenging, especially under changing climate conditions.
Sergio Naranjo, Francelino A. Rodrigues Jr., Georg Cadisch, Santiago Lopez-Ridaura, Mariela Fuentes, and Carsten Marohn
Hydrol. Earth Syst. Sci. Discuss.,
Revised manuscript accepted for HESSShort summary
This study pioneers in the integration of a spatially explicit soil erosion model with plot and watershed scale characterization and high resolution drone imagery to assess the effect of spatial resolution DTM on discharge and soil loss. Results showed reduction of slope due to resampling-down of DTM. High resolution translates into higher slope, denser fluvial system, and extremer values of soil loss reducing time of concentration and increasing soil loss at the outlet. Best resolution was 4 m.
Shervan Gharari, Martyn P. Clark, Naoki Mizukami, Wouter J. M. Knoben, Jefferson S. Wong, and Alain Pietroniro
Hydrol. Earth Syst. Sci., 24, 5953–5971,Short summary
This work explores the trade-off between the accuracy of the representation of geospatial data, such as land cover, soil type, and elevation zones, in a land (surface) model and its performance in the context of modeling. We used a vector-based setup instead of the commonly used grid-based setup to identify this trade-off. We also assessed the often neglected parameter uncertainty and its impact on the land model simulations.
Ganggang Zuo, Jungang Luo, Ni Wang, Yani Lian, and Xinxin He
Hydrol. Earth Syst. Sci., 24, 5491–5518,Short summary
A two-stage variational mode decomposition and support vector regression is designed to reduce the influence of boundary effects without removing or correcting boundary-affected decompositions. The proposed model significantly reduces the boundary effect consequences, saves modeling time and computation resources, barely overfits the calibration samples, and forecasts monthly runoff reasonably well compared to the benchmark models.
Nils Hinrich Kaplan, Theresa Blume, and Markus Weiler
Hydrol. Earth Syst. Sci., 24, 5453–5472,Short summary
In recent decades the demand for detailed information of spatial and temporal dynamics of the stream network has grown in the fields of eco-hydrology and extreme flow prediction. We use temporal streamflow intermittency data obtained at various sites using innovative sensing technology as well as spatial predictors to predict and map probabilities of streamflow intermittency. This approach has the potential to provide intermittency maps for hydrological modelling and management practices.
Mattia Neri, Juraj Parajka, and Elena Toth
Hydrol. Earth Syst. Sci., 24, 5149–5171,Short summary
One of the most informative ways to gain information on ungauged river sections is through the implementation of a rainfall-runoff model, exploiting the information collected in gauged catchments in the study area. This study analyses how the performances of different model regionalisation approaches are influenced by the informative content of the available regional data set, in order to identify the methods that are more suitable for the data availability in the region.
Stefania Camici, Christian Massari, Luca Ciabatta, Ivan Marchesini, and Luca Brocca
Hydrol. Earth Syst. Sci., 24, 4869–4885,Short summary
The paper performs the most comprehensive European-scale evaluation to date of satellite rainfall products for river flow prediction. In doing so, how errors transfer from satellite-based rainfall products into flood simulation is investigated in depth and, for the first time, quantitative guidelines on the use of these products for hydrological applications are provided. This result can represent a keystone in the use of satellite rainfall products, especially in data-scarce regions.
Renaud Hostache, Dominik Rains, Kaniska Mallick, Marco Chini, Ramona Pelich, Hans Lievens, Fabrizio Fenicia, Giovanni Corato, Niko E. C. Verhoest, and Patrick Matgen
Hydrol. Earth Syst. Sci., 24, 4793–4812,Short summary
Our objective is to investigate how satellite microwave sensors, particularly Soil Moisture and Ocean Salinity (SMOS), may help to reduce errors and uncertainties in soil moisture simulations with a large-scale conceptual hydro-meteorological model. We assimilated a long time series of SMOS observations into a hydro-meteorological model and showed that this helps to improve model predictions. This work therefore contributes to the development of faster and more accurate drought prediction tools.
Hui Sheng, Xiaomei Xu, Jian Hua Gao, Albert J. Kettner, Yong Shi, Chengfeng Xue, Ya Ping Wang, and Shu Gao
Hydrol. Earth Syst. Sci., 24, 4743–4761,Short summary
This paper investigates the variability of past flooding by applying a numerical model coupled with historical records of regional climate and anthropogenic activity under the deficiency of observations. We conclude that trends in flooding frequency were predominantly modulated by the intensity and frequency of extreme rainfall events, which highlights the need for the implementation of effective river engineering measures to counteract increasing flood risks as a result of the future.
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A numerical model was used to estimate annual and seasonal mean travel times across 14 long-term nested monitored catchments in the boreal region. The estimated travel times and young water fractions were consistent with observed variations of base cation concentration and stable water isotopes, δ18O. Soil type was the most important factor regulating the variation in mean travel times among sub-catchments, while the areal coverage of mires increased the young water fraction.
A numerical model was used to estimate annual and seasonal mean travel times across 14 long-term...