Articles | Volume 21, issue 6
https://doi.org/10.5194/hess-21-2817-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/hess-21-2817-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
09 Jun 2017
Research article |
| 09 Jun 2017
Unravelling abiotic and biotic controls on the seasonal water balance using data-driven dimensionless diagnostics
Simon Paul Seibert
CORRESPONDING AUTHOR
Karlsruhe Institute of Technology (KIT), Institute for Water and River Basin Management,
Chair of Hydrology, Kaiserstrasse 12, 76131 Karlsruhe, Germany
Conrad Jackisch
Karlsruhe Institute of Technology (KIT), Institute for Water and River Basin Management,
Chair of Hydrology, Kaiserstrasse 12, 76131 Karlsruhe, Germany
Uwe Ehret
Karlsruhe Institute of Technology (KIT), Institute for Water and River Basin Management,
Chair of Hydrology, Kaiserstrasse 12, 76131 Karlsruhe, Germany
Laurent Pfister
Luxembourg Institute of Science and Technology, Department Environmental Research
and Innovation, Catchment and Eco-hydrology research group, 5 avenue des
Hauts-Fourneaux, 4362 Esch/Alzette, Luxembourg
Erwin Zehe
Karlsruhe Institute of Technology (KIT), Institute for Water and River Basin Management,
Chair of Hydrology, Kaiserstrasse 12, 76131 Karlsruhe, Germany
Related authors
Simon Paul Seibert, Uwe Ehret, and Erwin Zehe
Hydrol. Earth Syst. Sci., 20, 3745–3763, https://doi.org/10.5194/hess-20-3745-2016, https://doi.org/10.5194/hess-20-3745-2016, 2016
Short summary
Short summary
While the assessment of "vertical" (magnitude) errors of streamflow simulations is standard practice, "horizontal" (timing) errors are rarely considered. To assess their role, we propose a method to quantify both errors simultaneously which closely resembles visual hydrograph comparison. Our results reveal differences in time–magnitude error statistics for different flow conditions. The proposed method thus offers novel perspectives for model diagnostics and evaluation.
Manuel Álvarez Chaves, Eduardo Acuña Espinoza, Uwe Ehret, and Anneli Guthke
EGUsphere, https://doi.org/10.5194/egusphere-2025-1699, https://doi.org/10.5194/egusphere-2025-1699, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
This study evaluates hybrid hydrological models that combine physics-based and data-driven components, using Information Theory to measure their relative contributions. When testing conceptual models with LSTMs that adjust parameters over time, we found performance primarily comes from the data-driven component, with physics constraints adding minimal value. We propose a quantitative tool to analyse this behaviour and suggest a workflow for diagnosing hybrid models.
Eduardo Acuña Espinoza, Frederik Kratzert, Daniel Klotz, Martin Gauch, Manuel Álvarez Chaves, Ralf Loritz, and Uwe Ehret
Hydrol. Earth Syst. Sci., 29, 1749–1758, https://doi.org/10.5194/hess-29-1749-2025, https://doi.org/10.5194/hess-29-1749-2025, 2025
Short summary
Short summary
Long short-term memory (LSTM) networks have demonstrated state-of-the-art performance for rainfall-runoff hydrological modelling. However, most studies focus on predictions at a daily scale, limiting the benefits of sub-daily (e.g. hourly) predictions in applications like flood forecasting. In this study, we introduce a new architecture, multi-frequency LSTM (MF-LSTM), designed to use inputs of various temporal frequencies to produce sub-daily (e.g. hourly) predictions at a moderate computational cost.
Evgeny Shavelzon, Erwin Zehe, and Yaniv Edery
EGUsphere, https://doi.org/10.22541/essoar.173687429.91307309/v1, https://doi.org/10.22541/essoar.173687429.91307309/v1, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
We analyze how chemical reactions and fluid movement interact in porous materials, focusing on how water paths form in underground environments. Using a thermodynamic approach, we track energy dissipation and entropy changes to understand this process. Over time, water channels become more defined, reducing chemical mixing and energy loss. Eventually, the system stabilizes, with flow concentrated in efficient pathways, minimizing further reactions and energy use.
Tim Busker, Daniela Rodriguez Castro, Sergiy Vorogushyn, Jaap Kwadijk, Davide Zoccatelli, Rafaella Loureiro, Heather J. Murdock, Laurent Pfister, Benjamin Dewals, Kymo Slager, Annegret H. Thieken, Jan Verkade, Patrick Willems, and Jeroen C. J. H. Aerts
EGUsphere, https://doi.org/10.5194/egusphere-2025-828, https://doi.org/10.5194/egusphere-2025-828, 2025
This preprint is open for discussion and under review for Natural Hazards and Earth System Sciences (NHESS).
Short summary
Short summary
In July 2021, the Netherlands, Luxembourg, Germany, and Belgium were hit by an extreme flood event with over 200 fatalities. Our study provides, for the first time, critical insights into the operational flood early-warning systems in this entire region. Based on 13 expert interviews, we conclude that the systems strongly improved in all countries. Interviewees stressed the need for operational impact-based forecasts, but emphasized that its operational implementation is challenging.
Maria Staudinger, Anna Herzog, Ralf Loritz, Tobias Houska, Sandra Pool, Diana Spieler, Paul D. Wagner, Juliane Mai, Jens Kiesel, Stephan Thober, Björn Guse, and Uwe Ehret
EGUsphere, https://doi.org/10.5194/egusphere-2025-1076, https://doi.org/10.5194/egusphere-2025-1076, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
Four process-based and four data-driven hydrological models are compared using different training data. We found process-based models to perform better with small data sets but stop learning soon, while data-driven models learn longer. The study highlights the importance of memory in data and the impact of different data sampling methods on model performance. The direct comparison of these models is novel and provides a clear understanding of their performance under various data conditions.
Eduardo Acuña Espinoza, Ralf Loritz, Frederik Kratzert, Daniel Klotz, Martin Gauch, Manuel Álvarez Chaves, and Uwe Ehret
Hydrol. Earth Syst. Sci., 29, 1277–1294, https://doi.org/10.5194/hess-29-1277-2025, https://doi.org/10.5194/hess-29-1277-2025, 2025
Short summary
Short summary
Data-driven techniques have shown the potential to outperform process-based models in rainfall–runoff simulations. Hybrid models, combining both approaches, aim to enhance accuracy and maintain interpretability. Expanding the set of test cases to evaluate hybrid models under different conditions, we test their generalization capabilities for extreme hydrological events.
Guilhem Türk, Christoph Johannes Gey, Bernd Reinhard Schöne, and Laurent Pfister
EGUsphere, https://doi.org/10.5194/egusphere-2024-4169, https://doi.org/10.5194/egusphere-2024-4169, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
Past stream flow dynamics can be assessed using the stable isotopes of oxygen (O16/O18) in streams and precipitation from various proxy sources. Here, we show how they are retrieved in precipitation for ~150 years using temperature records and an atmospheric circulation classification scheme. Our robust and assumption-lean approach compares to model performances in the literature, demonstrating atmospheric controls of the temperature influence on precipitation O16/O18 compositions.
Huibin Gao, Laurent Pfister, and James W. Kirchner
EGUsphere, https://doi.org/10.5194/egusphere-2025-613, https://doi.org/10.5194/egusphere-2025-613, 2025
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
Some streams respond to rainfall with flow that peaks twice: a sharp first peak followed by a broad second peak. We analyzed data from a catchment in Luxembourg to better understand the processes behind this phenomenon. Our results show that the first peak is mostly driven directly by rainfall, and the second peak is mostly driven by rain that infiltrates to groundwater. We also show that the relative importance of these two processes depends on how wet the landscape is before the rain falls.
Paolo Nasta, Günter Blöschl, Heye R. Bogena, Steffen Zacharias, Roland Baatz, Gabriëlle De Lannoy, Karsten H. Jensen, Salvatore Manfreda, Laurent Pfister, Ana M. Tarquis, Ilja van Meerveld, Marc Voltz, Yijian Zeng, William Kustas, Xin Li, Harry Vereecken, and Nunzio Romano
Hydrol. Earth Syst. Sci., 29, 465–483, https://doi.org/10.5194/hess-29-465-2025, https://doi.org/10.5194/hess-29-465-2025, 2025
Short summary
Short summary
The Unsolved Problems in Hydrology (UPH) initiative has emphasized the need to establish networks of multi-decadal hydrological observatories to tackle catchment-scale challenges on a global scale. This opinion paper provocatively discusses two endmembers of possible future hydrological observatory (HO) networks for a given hypothesized community budget: a comprehensive set of moderately instrumented observatories or, alternatively, a small number of highly instrumented supersites.
Ashish Manoj J, Ralf Loritz, Hoshin Gupta, and Erwin Zehe
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-375, https://doi.org/10.5194/hess-2024-375, 2024
Revised manuscript under review for HESS
Short summary
Short summary
Traditional hydrological models typically operate in a forward mode, simulating streamflow and other catchment fluxes based on precipitation input. In this study, we explored the possibility of reversing this process—inferring precipitation from streamflow data—to improve flood event modelling. We then used the generated precipitation series to run hydrological models, resulting in more accurate estimates of streamflow and soil moisture.
Karl Nicolaus van Zweel, Laurent Gourdol, Jean François Iffly, Loïc Léonard, François Barnich, Laurent Pfister, Erwin Zehe, and Christophe Hissler
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-259, https://doi.org/10.5194/essd-2024-259, 2024
Revised manuscript accepted for ESSD
Short summary
Short summary
Our study monitored groundwater in a Luxembourg forest over a year to understand water and chemical changes. We found seasonal variations in water chemistry, influenced by rainfall and soil interactions. This data helps predict environmental responses and manage water resources better. By measuring key parameters like pH and dissolved oxygen, our research provides valuable insights into groundwater behavior and serves as a resource for future environmental studies.
Svenja Hoffmeister, Rafael Bohn Reckziegel, Ben du Toit, Sibylle K. Hassler, Florian Kestel, Rebekka Maier, Jonathan P. Sheppard, and Erwin Zehe
Hydrol. Earth Syst. Sci., 28, 3963–3982, https://doi.org/10.5194/hess-28-3963-2024, https://doi.org/10.5194/hess-28-3963-2024, 2024
Short summary
Short summary
We studied a tree–crop ecosystem consisting of a blackberry field and an alder windbreak. In the water-scarce region, irrigation provides sufficient water for plant growth. The windbreak lowers the irrigation amount by reducing wind speed and therefore water transport into the atmosphere. These ecosystems could provide sustainable use of water-scarce landscapes, and we studied the complex interactions by observing several aspects (e.g. soil, nutrients, carbon assimilation, water).
Andrea L. Campoverde, Uwe Ehret, Patrick Ludwig, and Joaquim G. Pinto
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2024-134, https://doi.org/10.5194/gmd-2024-134, 2024
Revised manuscript not accepted
Short summary
Short summary
We looked at how well the model WRF-Hydro performed during the 2018 drought event in the River Rhine basin, even though it is typically used for floods. We used the meteorological ERA5 reanalysis dataset to simulate River Rhine’s streamflow and adjusted the model using parameters and actual discharge measurements. We focused on Lake Constance, a key part of the basin, but found issues with the model’s lake outflow simulation. By removing the lake module, we obtained more accurate results.
Laurent Gourdol, Michael K. Stewart, Uwe Morgenstern, and Laurent Pfister
Hydrol. Earth Syst. Sci., 28, 3519–3547, https://doi.org/10.5194/hess-28-3519-2024, https://doi.org/10.5194/hess-28-3519-2024, 2024
Short summary
Short summary
Determining water transit times in aquifers is key to a better understanding of groundwater resources and their sustainable management. For our research, we used high-accuracy tritium data from 35 springs draining the Luxembourg Sandstone aquifer. We assessed the mean transit times of groundwater and found that water moves on average more than 10 times more slowly vertically in the vadose zone of the aquifer (~12 m yr-1) than horizontally in its saturated zone (~170 m yr-1).
Tobias Karl David Weber, Lutz Weihermüller, Attila Nemes, Michel Bechtold, Aurore Degré, Efstathios Diamantopoulos, Simone Fatichi, Vilim Filipović, Surya Gupta, Tobias L. Hohenbrink, Daniel R. Hirmas, Conrad Jackisch, Quirijn de Jong van Lier, John Koestel, Peter Lehmann, Toby R. Marthews, Budiman Minasny, Holger Pagel, Martine van der Ploeg, Shahab Aldin Shojaeezadeh, Simon Fiil Svane, Brigitta Szabó, Harry Vereecken, Anne Verhoef, Michael Young, Yijian Zeng, Yonggen Zhang, and Sara Bonetti
Hydrol. Earth Syst. Sci., 28, 3391–3433, https://doi.org/10.5194/hess-28-3391-2024, https://doi.org/10.5194/hess-28-3391-2024, 2024
Short summary
Short summary
Pedotransfer functions (PTFs) are used to predict parameters of models describing the hydraulic properties of soils. The appropriateness of these predictions critically relies on the nature of the datasets for training the PTFs and the physical comprehensiveness of the models. This roadmap paper is addressed to PTF developers and users and critically reflects the utility and future of PTFs. To this end, we present a manifesto aiming at a paradigm shift in PTF research.
Sarah Quỳnh Giang Ho and Uwe Ehret
EGUsphere, https://doi.org/10.5194/egusphere-2024-2167, https://doi.org/10.5194/egusphere-2024-2167, 2024
Short summary
Short summary
In this paper, we use models to demonstrate that even small flood reservoirs – which capture water to avoid floods downstream – can be repurposed to release water in drier conditions without affecting their ability to protect against floods. By capturing water and releasing once water levels are low, we show that reservoirs can greatly increase water available in drought. Having more water coming in, however, is not necessarily better for drought protection.
Eduardo Acuña Espinoza, Ralf Loritz, Manuel Álvarez Chaves, Nicole Bäuerle, and Uwe Ehret
Hydrol. Earth Syst. Sci., 28, 2705–2719, https://doi.org/10.5194/hess-28-2705-2024, https://doi.org/10.5194/hess-28-2705-2024, 2024
Short summary
Short summary
Hydrological hybrid models promise to merge the performance of deep learning methods with the interpretability of process-based models. One hybrid approach is the dynamic parameterization of conceptual models using long short-term memory (LSTM) networks. We explored this method to evaluate the effect of the flexibility given by LSTMs on the process-based part.
Tobias L. Hohenbrink, Conrad Jackisch, Wolfgang Durner, Kai Germer, Sascha C. Iden, Janis Kreiselmeier, Frederic Leuther, Johanna C. Metzger, Mahyar Naseri, and Andre Peters
Earth Syst. Sci. Data, 15, 4417–4432, https://doi.org/10.5194/essd-15-4417-2023, https://doi.org/10.5194/essd-15-4417-2023, 2023
Short summary
Short summary
The article describes a collection of 572 data sets of soil water retention and unsaturated hydraulic conductivity data measured with state-of-the-art laboratory methods. Furthermore, the data collection contains basic soil properties such as soil texture and organic carbon content. We expect that the data will be useful for various important purposes, for example, the development of soil hydraulic property models and related pedotransfer functions.
Uwe Ehret and Pankaj Dey
Hydrol. Earth Syst. Sci., 27, 2591–2605, https://doi.org/10.5194/hess-27-2591-2023, https://doi.org/10.5194/hess-27-2591-2023, 2023
Short summary
Short summary
We propose the
c-u-curvemethod to characterize dynamical (time-variable) systems of all kinds.
Uis for uncertainty and expresses how well a system can be predicted in a given period of time.
Cis for complexity and expresses how predictability differs between different periods, i.e. how well predictability itself can be predicted. The method helps to better classify and compare dynamical systems across a wide range of disciplines, thus facilitating scientific collaboration.
Samuel Schroers, Ulrike Scherer, and Erwin Zehe
Hydrol. Earth Syst. Sci., 27, 2535–2557, https://doi.org/10.5194/hess-27-2535-2023, https://doi.org/10.5194/hess-27-2535-2023, 2023
Short summary
Short summary
The hydrological cycle shapes our landscape. With an accelerating change of the world's climate and hydrological dynamics, concepts of evolution of natural systems become more important. In this study, we elaborated a thermodynamic framework for runoff and sediment transport and show from model results as well as from measurements during extreme events that the developed concept is useful for understanding the evolution of the system's mass, energy, and entropy fluxes.
Patrick Ludwig, Florian Ehmele, Mário J. Franca, Susanna Mohr, Alberto Caldas-Alvarez, James E. Daniell, Uwe Ehret, Hendrik Feldmann, Marie Hundhausen, Peter Knippertz, Katharina Küpfer, Michael Kunz, Bernhard Mühr, Joaquim G. Pinto, Julian Quinting, Andreas M. Schäfer, Frank Seidel, and Christina Wisotzky
Nat. Hazards Earth Syst. Sci., 23, 1287–1311, https://doi.org/10.5194/nhess-23-1287-2023, https://doi.org/10.5194/nhess-23-1287-2023, 2023
Short summary
Short summary
Heavy precipitation in July 2021 led to widespread floods in western Germany and neighboring countries. The event was among the five heaviest precipitation events of the past 70 years in Germany, and the river discharges exceeded by far the statistical 100-year return values. Simulations of the event under future climate conditions revealed a strong and non-linear effect on flood peaks: for +2 K global warming, an 18 % increase in rainfall led to a 39 % increase of the flood peak in the Ahr river.
Susanna Mohr, Uwe Ehret, Michael Kunz, Patrick Ludwig, Alberto Caldas-Alvarez, James E. Daniell, Florian Ehmele, Hendrik Feldmann, Mário J. Franca, Christian Gattke, Marie Hundhausen, Peter Knippertz, Katharina Küpfer, Bernhard Mühr, Joaquim G. Pinto, Julian Quinting, Andreas M. Schäfer, Marc Scheibel, Frank Seidel, and Christina Wisotzky
Nat. Hazards Earth Syst. Sci., 23, 525–551, https://doi.org/10.5194/nhess-23-525-2023, https://doi.org/10.5194/nhess-23-525-2023, 2023
Short summary
Short summary
The flood event in July 2021 was one of the most severe disasters in Europe in the last half century. The objective of this two-part study is a multi-disciplinary assessment that examines the complex process interactions in different compartments, from meteorology to hydrological conditions to hydro-morphological processes to impacts on assets and environment. In addition, we address the question of what measures are possible to generate added value to early response management.
Judith Meyer, Malte Neuper, Luca Mathias, Erwin Zehe, and Laurent Pfister
Hydrol. Earth Syst. Sci., 26, 6163–6183, https://doi.org/10.5194/hess-26-6163-2022, https://doi.org/10.5194/hess-26-6163-2022, 2022
Short summary
Short summary
We identified and analysed the major atmospheric components of rain-intense thunderstorms that can eventually lead to flash floods: high atmospheric moisture, sufficient latent instability, and weak thunderstorm cell motion. Between 1981 and 2020, atmospheric conditions became likelier to support strong thunderstorms. However, the occurrence of extreme rainfall events as well as their rainfall intensity remained mostly unchanged.
Audrey Douinot, Jean François Iffly, Cyrille Tailliez, Claude Meisch, and Laurent Pfister
Hydrol. Earth Syst. Sci., 26, 5185–5206, https://doi.org/10.5194/hess-26-5185-2022, https://doi.org/10.5194/hess-26-5185-2022, 2022
Short summary
Short summary
The objective of the paper is to highlight the seasonal and singular shift of the transfer time distributions of two catchments (≅10 km2).
Based on 2 years of rainfall and discharge observations, we compare variations in the properties of TTDs with the physiographic characteristics of catchment areas and the eco-hydrological cycle. The paper eventually aims to deduce several factors conducive to particularly rapid and concentrated water transfers, which leads to flash floods.
Ralf Loritz, Maoya Bassiouni, Anke Hildebrandt, Sibylle K. Hassler, and Erwin Zehe
Hydrol. Earth Syst. Sci., 26, 4757–4771, https://doi.org/10.5194/hess-26-4757-2022, https://doi.org/10.5194/hess-26-4757-2022, 2022
Short summary
Short summary
In this study, we combine a deep-learning approach that predicts sap flow with a hydrological model to improve soil moisture and transpiration estimates at the catchment scale. Our results highlight that hybrid-model approaches, combining machine learning with physically based models, are a promising way to improve our ability to make hydrological predictions.
Alessandro Montemagno, Christophe Hissler, Victor Bense, Adriaan J. Teuling, Johanna Ziebel, and Laurent Pfister
Biogeosciences, 19, 3111–3129, https://doi.org/10.5194/bg-19-3111-2022, https://doi.org/10.5194/bg-19-3111-2022, 2022
Short summary
Short summary
We investigated the biogeochemical processes that dominate the release and retention of elements (nutrients and potentially toxic elements) during litter degradation. Our results show that toxic elements are retained in the litter, while nutrients are released in solution during the first stages of degradation. This seems linked to the capability of trees to distribute the elements between degradation-resistant and non-degradation-resistant compounds of leaves according to their chemical nature.
Samuel Schroers, Olivier Eiff, Axel Kleidon, Ulrike Scherer, Jan Wienhöfer, and Erwin Zehe
Hydrol. Earth Syst. Sci., 26, 3125–3150, https://doi.org/10.5194/hess-26-3125-2022, https://doi.org/10.5194/hess-26-3125-2022, 2022
Short summary
Short summary
In hydrology the formation of landform patterns is of special interest as changing forcings of the natural systems, such as climate or land use, will change these structures. In our study we developed a thermodynamic framework for surface runoff on hillslopes and highlight the differences of energy conversion patterns on two related spatial and temporal scales. The results indicate that surface runoff on hillslopes approaches a maximum power state.
Alexander Sternagel, Ralf Loritz, Brian Berkowitz, and Erwin Zehe
Hydrol. Earth Syst. Sci., 26, 1615–1629, https://doi.org/10.5194/hess-26-1615-2022, https://doi.org/10.5194/hess-26-1615-2022, 2022
Short summary
Short summary
We present a (physically based) Lagrangian approach to simulate diffusive mixing processes on the pore scale beyond perfectly mixed conditions. Results show the feasibility of the approach for reproducing measured mixing times and concentrations of isotopes over pore sizes and that typical shapes of breakthrough curves (normally associated with non-uniform transport in heterogeneous soils) may also occur as a result of imperfect subscale mixing in a macroscopically homogeneous soil matrix.
Erwin Zehe, Ralf Loritz, Yaniv Edery, and Brian Berkowitz
Hydrol. Earth Syst. Sci., 25, 5337–5353, https://doi.org/10.5194/hess-25-5337-2021, https://doi.org/10.5194/hess-25-5337-2021, 2021
Short summary
Short summary
This study uses the concepts of entropy and work to quantify and explain the emergence of preferential flow and transport in heterogeneous saturated porous media. We found that the downstream concentration of solutes in preferential pathways implies a downstream declining entropy in the transverse distribution of solute transport pathways. Preferential flow patterns with lower entropies emerged within media of higher heterogeneity – a stronger self-organization despite a higher randomness.
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, https://doi.org/10.5194/hess-25-5277-2021, https://doi.org/10.5194/hess-25-5277-2021, 2021
Laurent Gourdol, Rémi Clément, Jérôme Juilleret, Laurent Pfister, and Christophe Hissler
Hydrol. Earth Syst. Sci., 25, 1785–1812, https://doi.org/10.5194/hess-25-1785-2021, https://doi.org/10.5194/hess-25-1785-2021, 2021
Short summary
Short summary
Electrical resistivity tomography (ERT) is a remarkable tool for characterizing the regolith, but its use over large areas remains cumbersome due to the requirement of small electrode spacing (ES). In this study we document the issues of using oversized ESs and propose a new approach to overcome this limitation. We demonstrate that our protocol significantly improves the accuracy of ERT profiles using large ES and offers a cost-effective means for carrying out large-scale surveys.
Jan Bondy, Jan Wienhöfer, Laurent Pfister, and Erwin Zehe
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2021-174, https://doi.org/10.5194/hess-2021-174, 2021
Manuscript not accepted for further review
Short summary
Short summary
The Budyko curve is a widely-used and simple framework to predict the mean water balance of river catchments. While many catchments are in close accordance with the Budyko curve, others show more or less significant deviations. Our study aims at better understanding the role of soil storage characteristics in the mean water balance and offsets from the Budyko curve. Soil storage proved to be a very sensitive property and potentially explains significant deviations from the curve.
Alexander Sternagel, Ralf Loritz, Julian Klaus, Brian Berkowitz, and Erwin Zehe
Hydrol. Earth Syst. Sci., 25, 1483–1508, https://doi.org/10.5194/hess-25-1483-2021, https://doi.org/10.5194/hess-25-1483-2021, 2021
Short summary
Short summary
The key innovation of the study is a method to simulate reactive solute transport in the vadose zone within a Lagrangian framework. We extend the LAST-Model with a method to account for non-linear sorption and first-order degradation processes during unsaturated transport of reactive substances in the matrix and macropores. Model evaluations using bromide and pesticide data from irrigation experiments under different flow conditions on various timescales show the feasibility of the method.
Elnaz Azmi, Uwe Ehret, Steven V. Weijs, Benjamin L. Ruddell, and Rui A. P. Perdigão
Hydrol. Earth Syst. Sci., 25, 1103–1115, https://doi.org/10.5194/hess-25-1103-2021, https://doi.org/10.5194/hess-25-1103-2021, 2021
Short summary
Short summary
Computer models should be as simple as possible but not simpler. Simplicity refers to the length of the model and the effort it takes the model to generate its output. Here we present a practical technique for measuring the latter by the number of memory visits during model execution by
Strace, a troubleshooting and monitoring program. The advantage of this approach is that it can be applied to any computer-based model, which facilitates model intercomparison.
Samuel Schroers, Olivier Eiff, Axel Kleidon, Jan Wienhöfer, and Erwin Zehe
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2021-79, https://doi.org/10.5194/hess-2021-79, 2021
Manuscript not accepted for further review
Short summary
Short summary
In this study we ask the basic question why surface runoff forms drainage networks and confluences at all and how structural macro form and micro topography is a result of thermodynamic laws. We find that on a macro level hillslopes should tend from negative exponential towards exponential forms and that on a micro level the formation of rills goes hand in hand with drainage network formation of river basins. We hypothesize that we can learn more about erosion processes if we extend this theory.
Nicolas Björn Rodriguez, Laurent Pfister, Erwin Zehe, and Julian Klaus
Hydrol. Earth Syst. Sci., 25, 401–428, https://doi.org/10.5194/hess-25-401-2021, https://doi.org/10.5194/hess-25-401-2021, 2021
Short summary
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.
Ralf Loritz, Markus Hrachowitz, Malte Neuper, and Erwin Zehe
Hydrol. Earth Syst. Sci., 25, 147–167, https://doi.org/10.5194/hess-25-147-2021, https://doi.org/10.5194/hess-25-147-2021, 2021
Short summary
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.
Conrad Jackisch, Samuel Knoblauch, Theresa Blume, Erwin Zehe, and Sibylle K. Hassler
Biogeosciences, 17, 5787–5808, https://doi.org/10.5194/bg-17-5787-2020, https://doi.org/10.5194/bg-17-5787-2020, 2020
Short summary
Short summary
We developed software to calculate the root water uptake (RWU) of beech tree roots from soil moisture dynamics. We present our approach and compare RWU to measured sap flow in the tree stem. The study relates to two sites that are similar in topography and weather but with contrasting soils. While sap flow is very similar between the two sites, the RWU is different. This suggests that soil characteristics have substantial influence. Our easy-to-implement RWU estimate may help further studies.
Jasper Foets, Carlos E. Wetzel, Núria Martínez-Carreras, Adriaan J. Teuling, Jean-François Iffly, and Laurent Pfister
Hydrol. Earth Syst. Sci., 24, 4709–4725, https://doi.org/10.5194/hess-24-4709-2020, https://doi.org/10.5194/hess-24-4709-2020, 2020
Short summary
Short summary
Diatoms (microscopic algae) are regarded as useful tracers in catchment hydrology. However, diatom analysis is labour-intensive; therefore, only a limited number of samples can be analysed. To reduce this number, we explored the potential for a time-integrated mass-flux sampler to provide a representative sample of the diatom assemblage for a whole storm run-off event. Our results indicate that the Phillips sampler did indeed sample representative communities during two of the three events.
Stephanie Thiesen, Diego M. Vieira, Mirko Mälicke, Ralf Loritz, J. Florian Wellmann, and Uwe Ehret
Hydrol. Earth Syst. Sci., 24, 4523–4540, https://doi.org/10.5194/hess-24-4523-2020, https://doi.org/10.5194/hess-24-4523-2020, 2020
Short summary
Short summary
A spatial interpolator has been proposed for exploring the information content of the data in the light of geostatistics and information theory. It showed comparable results to traditional interpolators, with the advantage of presenting generalization properties. We discussed three different ways of combining distributions and their implications for the probabilistic results. By its construction, the method provides a suitable and flexible framework for uncertainty analysis and decision-making.
Uwe Ehret, Rik van Pruijssen, Marina Bortoli, Ralf Loritz, Elnaz Azmi, and Erwin Zehe
Hydrol. Earth Syst. Sci., 24, 4389–4411, https://doi.org/10.5194/hess-24-4389-2020, https://doi.org/10.5194/hess-24-4389-2020, 2020
Short summary
Short summary
In this paper we propose adaptive clustering as a new method for reducing the computational efforts of distributed modelling. It consists of identifying similar-acting model elements during the runtime, clustering them, running the model for just a few representatives per cluster, and mapping their results to the remaining model elements in the cluster. With the example of a hydrological model, we show that this saves considerable computation time, while largely maintaining the output quality.
Mirko Mälicke, Sibylle K. Hassler, Theresa Blume, Markus Weiler, and Erwin Zehe
Hydrol. Earth Syst. Sci., 24, 2633–2653, https://doi.org/10.5194/hess-24-2633-2020, https://doi.org/10.5194/hess-24-2633-2020, 2020
Short summary
Short summary
We could show that distributed soil moisture time series bear a considerable amount of information about dynamic changes in soil moisture. We developed a new method to describe spatial patterns and analyze their persistency. By combining uncertainty propagation with information theory, we were able to calculate the information content of spatial similarity with respect to measurement uncertainty. This does help to understand when and why the soil is drying in an organized manner.
Brian Berkowitz and Erwin Zehe
Hydrol. Earth Syst. Sci., 24, 1831–1858, https://doi.org/10.5194/hess-24-1831-2020, https://doi.org/10.5194/hess-24-1831-2020, 2020
Short summary
Short summary
We present a
blueprintfor a unified modelling framework to quantify chemical transport in both surface water and groundwater systems. There has been extensive debate over recent decades, particularly in the surface water literature, about how to explain and account for long travel times of chemical species that are distinct from water flow (rainfall-runoff) travel times. We suggest a powerful modelling framework known to be robust and effective from the field of groundwater hydrology.
Conrad Jackisch, Kai Germer, Thomas Graeff, Ines Andrä, Katrin Schulz, Marcus Schiedung, Jaqueline Haller-Jans, Jonas Schneider, Julia Jaquemotte, Philipp Helmer, Leander Lotz, Andreas Bauer, Irene Hahn, Martin Šanda, Monika Kumpan, Johann Dorner, Gerrit de Rooij, Stefan Wessel-Bothe, Lorenz Kottmann, Siegfried Schittenhelm, and Wolfgang Durner
Earth Syst. Sci. Data, 12, 683–697, https://doi.org/10.5194/essd-12-683-2020, https://doi.org/10.5194/essd-12-683-2020, 2020
Short summary
Short summary
Soil water content and matric potential are central hydrological state variables. A large variety of automated probes and sensor systems for field monitoring exist. In a field experiment under idealised conditions we compared 15 systems for soil moisture and 14 systems for matric potential. The individual records of one system agree well with the others. Most records are also plausible. However, the absolute values of the different measuring systems span a very large range of possible truths.
Bernd R. Schöne, Aliona E. Meret, Sven M. Baier, Jens Fiebig, Jan Esper, Jeffrey McDonnell, and Laurent Pfister
Hydrol. Earth Syst. Sci., 24, 673–696, https://doi.org/10.5194/hess-24-673-2020, https://doi.org/10.5194/hess-24-673-2020, 2020
Short summary
Short summary
We present the first annually resolved stable isotope record (1819–1998) from shells of Swedish river mussels. Data reflect hydrological processes in the catchment and changes in the isotope value of local precipitation. The latter is related to the origin of moisture from which precipitation formed (North Atlantic or the Arctic) and governed by large-scale atmospheric circulation patterns. Results help to better understand climate dynamics and constrain ecological changes in river ecosystems.
Alexander Sternagel, Ralf Loritz, Wolfgang Wilcke, and Erwin Zehe
Hydrol. Earth Syst. Sci., 23, 4249–4267, https://doi.org/10.5194/hess-23-4249-2019, https://doi.org/10.5194/hess-23-4249-2019, 2019
Short summary
Short summary
We present our hydrological LAST-Model to simulate preferential soil water flow and tracer transport in macroporous soils. It relies on a Lagrangian perspective of the movement of discrete water particles carrying tracer masses through the subsoil and is hence an alternative approach to common models. Sensitivity analyses reveal the physical validity of the model concept and evaluation tests show that LAST can depict well observed tracer mass profiles with fingerprints of preferential flow.
Axel Kleidon, Erwin Zehe, and Ralf Loritz
Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2019-52, https://doi.org/10.5194/esd-2019-52, 2019
Manuscript not accepted for further review
Short summary
Short summary
Many fluxes in Earth systems are not homogeneously distributed across space, but occur highly concentrated in structures, such as turbulent eddies, river networks, vascular networks of plants, or human-made infrastructures. Yet, the highly-organized nature of these fluxes is typically only described at a rudimentary level, if at all. We propose that it requires a novel approach to describe these structures that focuses on the work done to build and maintain these structures, and the feedbacks.
Ralf Loritz, Axel Kleidon, Conrad Jackisch, Martijn Westhoff, Uwe Ehret, Hoshin Gupta, and Erwin Zehe
Hydrol. Earth Syst. Sci., 23, 3807–3821, https://doi.org/10.5194/hess-23-3807-2019, https://doi.org/10.5194/hess-23-3807-2019, 2019
Short summary
Short summary
In this study, we develop a topographic index explaining hydrological similarity within a energy-centered framework, with the observation that the majority of potential energy is dissipated when rainfall becomes runoff.
Malte Neuper and Uwe Ehret
Hydrol. Earth Syst. Sci., 23, 3711–3733, https://doi.org/10.5194/hess-23-3711-2019, https://doi.org/10.5194/hess-23-3711-2019, 2019
Short summary
Short summary
In this study, we apply a data-driven approach to quantitatively estimate precipitation using weather radar data. The method is based on information theory concepts. It uses predictive relations expressed by empirical discrete probability distributions, which are directly derived from data rather than the standard deterministic functions.
Stephanie Thiesen, Paul Darscheid, and Uwe Ehret
Hydrol. Earth Syst. Sci., 23, 1015–1034, https://doi.org/10.5194/hess-23-1015-2019, https://doi.org/10.5194/hess-23-1015-2019, 2019
Short summary
Short summary
We present a data-driven approach created to explore the full information of data sets, avoiding parametric assumptions. The evaluations are based on Information Theory concepts, introducing an objective measure of information and uncertainty. The approach was applied to automatically identify rainfall-runoff events in discharge time series, however it is generic enough to be adapted to other practical applications.
Erwin Zehe, Ralf Loritz, Conrad Jackisch, Martijn Westhoff, Axel Kleidon, Theresa Blume, Sibylle K. Hassler, and Hubert H. Savenije
Hydrol. Earth Syst. Sci., 23, 971–987, https://doi.org/10.5194/hess-23-971-2019, https://doi.org/10.5194/hess-23-971-2019, 2019
Martijn Westhoff, Axel Kleidon, Stan Schymanski, Benjamin Dewals, Femke Nijsse, Maik Renner, Henk Dijkstra, Hisashi Ozawa, Hubert Savenije, Han Dolman, Antoon Meesters, and Erwin Zehe
Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2019-6, https://doi.org/10.5194/esd-2019-6, 2019
Publication in ESD not foreseen
Short summary
Short summary
Even models relying on physical laws have parameters that need to be measured or estimated. Thermodynamic optimality principles potentially offer a way to reduce the number of estimated parameters by stating that a system evolves to an optimum state. These principles have been applied successfully within the Earth system, but it is often unclear what to optimize and how. In this review paper we identify commonalities between different successful applications as well as some doubtful applications.
Nevil Quinn, Günter Blöschl, András Bárdossy, Attilio Castellarin, Martyn Clark, Christophe Cudennec, Demetris Koutsoyiannis, Upmanu Lall, Lubomir Lichner, Juraj Parajka, Christa D. Peters-Lidard, Graham Sander, Hubert Savenije, Keith Smettem, Harry Vereecken, Alberto Viglione, Patrick Willems, Andy Wood, Ross Woods, Chong-Yu Xu, and Erwin Zehe
Proc. IAHS, 380, 3–8, https://doi.org/10.5194/piahs-380-3-2018, https://doi.org/10.5194/piahs-380-3-2018, 2018
Laurent Gourdol, Rémi Clément, Jérôme Juilleret, Laurent Pfister, and Christophe Hissler
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2018-519, https://doi.org/10.5194/hess-2018-519, 2018
Revised manuscript not accepted
Short summary
Short summary
Electrical Resistivity Tomography (ERT) is a remarkable tool for characterizing the geometry and properties of the regolith. However, its use for large horizontal surveys remains cumbersome to characterize shallow subsurface structures due to the requirement of small electrode spacing increments. Here we propose a new approach to overcome this limitation. We demonstrate that our protocol significantly improves the accuracy of ERT profiles when using large electrode spacing increments.
Barbara Glaser, Marta Antonelli, Marco Chini, Laurent Pfister, and Julian Klaus
Hydrol. Earth Syst. Sci., 22, 5987–6003, https://doi.org/10.5194/hess-22-5987-2018, https://doi.org/10.5194/hess-22-5987-2018, 2018
Short summary
Short summary
We demonstrate how thermal infrared images can be used for mapping the appearance and disappearance of water at the surface. The use of thermal infrared images allows for mapping this appearance and disappearance for various temporal and spatial resolutions, and the images can be understood intuitively. We explain the necessary steps in detail, from image acquisition to final processing, by relying on image examples and experience from an 18-month mapping campaign.
Nevil Quinn, Günter Blöschl, András Bárdossy, Attilio Castellarin, Martyn Clark, Christophe Cudennec, Demetris Koutsoyiannis, Upmanu Lall, Lubomir Lichner, Juraj Parajka, Christa D. Peters-Lidard, Graham Sander, Hubert Savenije, Keith Smettem, Harry Vereecken, Alberto Viglione, Patrick Willems, Andy Wood, Ross Woods, Chong-Yu Xu, and Erwin Zehe
Hydrol. Earth Syst. Sci., 22, 5735–5739, https://doi.org/10.5194/hess-22-5735-2018, https://doi.org/10.5194/hess-22-5735-2018, 2018
Mirko Mälicke, Sibylle K. Hassler, Markus Weiler, Theresa Blume, and Erwin Zehe
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2018-396, https://doi.org/10.5194/hess-2018-396, 2018
Manuscript not accepted for further review
Short summary
Short summary
In this study we use time dependent variograms to identify periods of organized soil moisture during drying. We could identify emerging spatial patterns which imply periods of terrestrial control on soil moisture organization. The coupling of time dependent variograms with density based clustering is a new approach to detect similarity in spatial patterns. The presented method is useful to describe states of organization and improve kriging workflows by extending their prerequisites.
Ralf Loritz, Hoshin Gupta, Conrad Jackisch, Martijn Westhoff, Axel Kleidon, Uwe Ehret, and Erwin Zehe
Hydrol. Earth Syst. Sci., 22, 3663–3684, https://doi.org/10.5194/hess-22-3663-2018, https://doi.org/10.5194/hess-22-3663-2018, 2018
Short summary
Short summary
In this study we explore the role of spatially distributed information on hydrological modeling. For that, we develop and test an approach which draws upon information theory and thermodynamic reasoning. We show that the proposed set of methods provide a powerful framework for understanding and diagnosing how and when process organization and functional similarity of hydrological systems emerge in time and, hence, when which landscape characteristic is important in a model application.
Conrad Jackisch and Erwin Zehe
Hydrol. Earth Syst. Sci., 22, 3639–3662, https://doi.org/10.5194/hess-22-3639-2018, https://doi.org/10.5194/hess-22-3639-2018, 2018
Short summary
Short summary
We present a Lagrangian model for non-uniform soil water dynamics. It handles 2-D diffusion (based on a spatial random walk and implicit pore space redistribution) and 1-D advection in representative macropores (as film flow with dynamic interaction with the soil matrix). The interplay between the domains is calculated based on an energy-balance approach which does not require any additional parameterisation. Model tests give insight into the evolution of the non-uniform infiltration patterns.
Michael P. Schwab, Julian Klaus, Laurent Pfister, and Markus Weiler
Biogeosciences, 15, 2177–2188, https://doi.org/10.5194/bg-15-2177-2018, https://doi.org/10.5194/bg-15-2177-2018, 2018
Short summary
Short summary
We studied the diel fluctuations of dissolved organic carbon (DOC) concentrations in a small stream in Luxembourg. We identified an increased proportion of DOC from terrestrial sources as responsible for the peaks in DOC in the afternoon. Warmer water temperatures in the riparian zone in the afternoon increased the amount of water flowing towards the stream. Consequently, an increased amount of DOC-rich water from the riparian zone was entering the stream.
Simon Höllering, Jan Wienhöfer, Jürgen Ihringer, Luis Samaniego, and Erwin Zehe
Hydrol. Earth Syst. Sci., 22, 203–220, https://doi.org/10.5194/hess-22-203-2018, https://doi.org/10.5194/hess-22-203-2018, 2018
Short summary
Short summary
Hydrological fingerprints are introduced as response targets for sensitivity analysis and combined with a conventional approach using streamflow data for a temporally resolved sensitivity analysis. The joint benefit of both approaches is presented for several headwater catchments. The approach allows discerning a clarified pattern for parameter influences pinpointed to diverse response characteristics and detecting even slight regional differences.
Michael P. Schwab, Julian Klaus, Laurent Pfister, and Markus Weiler
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2017-416, https://doi.org/10.5194/hess-2017-416, 2017
Revised manuscript not accepted
Lisa Angermann, Conrad Jackisch, Niklas Allroggen, Matthias Sprenger, Erwin Zehe, Jens Tronicke, Markus Weiler, and Theresa Blume
Hydrol. Earth Syst. Sci., 21, 3727–3748, https://doi.org/10.5194/hess-21-3727-2017, https://doi.org/10.5194/hess-21-3727-2017, 2017
Short summary
Short summary
This study investigates the temporal dynamics and response velocities of lateral preferential flow at the hillslope. The results are compared to catchment response behavior to infer the large-scale implications of the observed processes. A large portion of mobile water flows through preferential flow paths in the structured soils, causing an immediate discharge response. The study presents a methodological approach to cover the spatial and temporal domain of these highly heterogeneous processes.
Conrad Jackisch, Lisa Angermann, Niklas Allroggen, Matthias Sprenger, Theresa Blume, Jens Tronicke, and Erwin Zehe
Hydrol. Earth Syst. Sci., 21, 3749–3775, https://doi.org/10.5194/hess-21-3749-2017, https://doi.org/10.5194/hess-21-3749-2017, 2017
Short summary
Short summary
Rapid subsurface flow in structured soils facilitates fast vertical and lateral redistribution of event water. We present its in situ exploration through local measurements and irrigation experiments. Special emphasis is given to a coherent combination of hydrological and geophysical methods. The study highlights that form and function operate as conjugated pairs. Dynamic imaging through time-lapse GPR was key to observing both and to identifying hydrologically relevant structures.
Ralf Loritz, Sibylle K. Hassler, Conrad Jackisch, Niklas Allroggen, Loes van Schaik, Jan Wienhöfer, and Erwin Zehe
Hydrol. Earth Syst. Sci., 21, 1225–1249, https://doi.org/10.5194/hess-21-1225-2017, https://doi.org/10.5194/hess-21-1225-2017, 2017
Short summary
Short summary
In this study we examine whether we can step beyond the qualitative character of perceptual models by using them as a blueprint for setting up representative hillslope models. Thereby we test the hypothesis of whether a single hillslope can represent the functioning of an entire lower mesoscale catchment in a spatially aggregated way.
Benjamin Müller, Matthias Bernhardt, Conrad Jackisch, and Karsten Schulz
Hydrol. Earth Syst. Sci., 20, 3765–3775, https://doi.org/10.5194/hess-20-3765-2016, https://doi.org/10.5194/hess-20-3765-2016, 2016
Short summary
Short summary
A technology for the spatial derivation of soil texture classes is presented. Information about soil texture is key for predicting the local and regional hydrological cycle. It is needed for the calculation of soil water movement, the share of surface runoff, the evapotranspiration rate and others. Nevertheless, the derivation of soil texture classes is expensive and time-consuming. The presented technique uses soil samples and remotely sensed data for estimating their spatial distribution.
Simon Paul Seibert, Uwe Ehret, and Erwin Zehe
Hydrol. Earth Syst. Sci., 20, 3745–3763, https://doi.org/10.5194/hess-20-3745-2016, https://doi.org/10.5194/hess-20-3745-2016, 2016
Short summary
Short summary
While the assessment of "vertical" (magnitude) errors of streamflow simulations is standard practice, "horizontal" (timing) errors are rarely considered. To assess their role, we propose a method to quantify both errors simultaneously which closely resembles visual hydrograph comparison. Our results reveal differences in time–magnitude error statistics for different flow conditions. The proposed method thus offers novel perspectives for model diagnostics and evaluation.
Erwin Zehe and Conrad Jackisch
Hydrol. Earth Syst. Sci., 20, 3511–3526, https://doi.org/10.5194/hess-20-3511-2016, https://doi.org/10.5194/hess-20-3511-2016, 2016
Simon Höllering, Jürgen Ihringer, Luis Samaniego, and Erwin Zehe
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2016-249, https://doi.org/10.5194/hess-2016-249, 2016
Preprint withdrawn
M. Westhoff, E. Zehe, P. Archambeau, and B. Dewals
Hydrol. Earth Syst. Sci., 20, 479–486, https://doi.org/10.5194/hess-20-479-2016, https://doi.org/10.5194/hess-20-479-2016, 2016
Short summary
Short summary
We derived mathematical formulations of relations between relative wetness and gradients driving run-off and evaporation for a one-box model such that, when conductances are optimized with the maximum power principle, the model leads exactly to a point on the Budyko curve.
With dry spells and dynamics in actual evaporation added, the model compared well with catchment observations without calibrating any parameter.
The maximum-power principle may thus be used to derive the Budyko curve.
N. Martínez-Carreras, C. E. Wetzel, J. Frentress, L. Ector, J. J. McDonnell, L. Hoffmann, and L. Pfister
Hydrol. Earth Syst. Sci., 19, 3133–3151, https://doi.org/10.5194/hess-19-3133-2015, https://doi.org/10.5194/hess-19-3133-2015, 2015
Short summary
Short summary
We tested the hypothesis that different diatom species assemblages inhabit specific moisture domains of the catchment and, consequently, the presence of certain species assemblages in the stream during runoff events offers the potential for recording whether there was hydrological connectivity between these domains or not. In the Weierbach catchment, the transport of aerial diatoms during events suggested a rapid connectivity between the soil surface and the stream.
U. Scherer and E. Zehe
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hessd-12-3527-2015, https://doi.org/10.5194/hessd-12-3527-2015, 2015
Revised manuscript not accepted
Short summary
Short summary
This paper presents the development, parameterization and verification of a process-based soil erosion model for the catchment scale, which balances necessary complexity with greatest possible simplicity. We used the hydrologic model CATFLOW as a platform and further developed it to CATFLOW-SED by integrating approaches to simulate soil erosion. The model was validated on a hierarchy of scales which is characteristic for the governing processes.
E. Zehe, U. Ehret, L. Pfister, T. Blume, B. Schröder, M. Westhoff, C. Jackisch, S. J. Schymanski, M. Weiler, K. Schulz, N. Allroggen, J. Tronicke, L. van Schaik, P. Dietrich, U. Scherer, J. Eccard, V. Wulfmeyer, and A. Kleidon
Hydrol. Earth Syst. Sci., 18, 4635–4655, https://doi.org/10.5194/hess-18-4635-2014, https://doi.org/10.5194/hess-18-4635-2014, 2014
U. Ehret, H. V. Gupta, M. Sivapalan, S. V. Weijs, S. J. Schymanski, G. Blöschl, A. N. Gelfan, C. Harman, A. Kleidon, T. A. Bogaard, D. Wang, T. Wagener, U. Scherer, E. Zehe, M. F. P. Bierkens, G. Di Baldassarre, J. Parajka, L. P. H. van Beek, A. van Griensven, M. C. Westhoff, and H. C. Winsemius
Hydrol. Earth Syst. Sci., 18, 649–671, https://doi.org/10.5194/hess-18-649-2014, https://doi.org/10.5194/hess-18-649-2014, 2014
J. Wienhöfer and E. Zehe
Hydrol. Earth Syst. Sci., 18, 121–138, https://doi.org/10.5194/hess-18-121-2014, https://doi.org/10.5194/hess-18-121-2014, 2014
M. Liu, A. Bárdossy, and E. Zehe
Hydrol. Earth Syst. Sci., 17, 4685–4699, https://doi.org/10.5194/hess-17-4685-2013, https://doi.org/10.5194/hess-17-4685-2013, 2013
E. Zehe, U. Ehret, T. Blume, A. Kleidon, U. Scherer, and M. Westhoff
Hydrol. Earth Syst. Sci., 17, 4297–4322, https://doi.org/10.5194/hess-17-4297-2013, https://doi.org/10.5194/hess-17-4297-2013, 2013
M. C. Westhoff and E. Zehe
Hydrol. Earth Syst. Sci., 17, 3141–3157, https://doi.org/10.5194/hess-17-3141-2013, https://doi.org/10.5194/hess-17-3141-2013, 2013
A. M. J. Coenders-Gerrits, L. Hopp, H. H. G. Savenije, and L. Pfister
Hydrol. Earth Syst. Sci., 17, 1749–1763, https://doi.org/10.5194/hess-17-1749-2013, https://doi.org/10.5194/hess-17-1749-2013, 2013
A. Kleidon, E. Zehe, U. Ehret, and U. Scherer
Hydrol. Earth Syst. Sci., 17, 225–251, https://doi.org/10.5194/hess-17-225-2013, https://doi.org/10.5194/hess-17-225-2013, 2013
J. Wienhöfer, K. Germer, F. Lindenmaier, A. Färber, and E. Zehe
Hydrol. Earth Syst. Sci., 13, 1145–1161, https://doi.org/10.5194/hess-13-1145-2009, https://doi.org/10.5194/hess-13-1145-2009, 2009
Related subject area
Subject: Catchment hydrology | Techniques and Approaches: Theory development
Causal relationships of vegetation productivity with root zone water availability and atmospheric dryness at the catchment scale
Annual memory in the terrestrial water cycle
Can system dynamics explain long-term hydrological behaviors? The role of endogenous linking structure
Catchment hydrological response and transport are affected differently by precipitation intensity and antecedent wetness
Characterizing nonlinear, nonstationary, and heterogeneous hydrologic behavior using ensemble rainfall–runoff analysis (ERRA): proof of concept
The role of catchment characteristics, discharge, and active layer thaw on seasonal stream chemistry across ten permafrost catchments
Ratio limits of water storage and outflow in a rainfall–runoff process
Delayed Stormflow Generation in a Semi-humid Forested Watershed Controlled by Soil Water Storage and Groundwater
Technical Note: The divide and measure nonconformity – how metrics can mislead when we evaluate on different data partitions
Bimodal hydrographs in a semi-humid forested watershed: characteristics and occurrence conditions
Flood drivers and trends: a case study of the Geul River catchment (the Netherlands) over the past half century
Power law between the apparent drainage density and the pruning area
HESS Opinion: Floods and droughts – Land use, soil management, and landscape hydrology are more significant drivers than increasing temperatures
Stream water sourcing from high-elevation snowpack inferred from stable isotopes of water: a novel application of d-excess values
Elasticity curves describe streamflow sensitivity to precipitation across the entire flow distribution
Seasonal and interannual dissolved organic carbon transport process dynamics in a subarctic headwater catchment revealed by high-resolution measurements
Links between seasonal suprapermafrost groundwater, the hydrothermal change of the active layer, and river runoff in alpine permafrost watersheds
Technical note: Isotopic fractionation of evaporating waters: effect of sub-daily atmospheric variations and eventual depletion of heavy isotopes
Increased nonstationarity of stormflow threshold behaviors in a forested watershed due to abrupt earthquake disturbance
HESS Opinions: Are soils overrated in hydrology?
Hydrologic implications of projected changes in rain-on-snow melt for Great Lakes Basin watersheds
A hydrological framework for persistent pools along non-perennial rivers
Evidence-based requirements for perceptualising intercatchment groundwater flow in hydrological models
Droughts can reduce the nitrogen retention capacity of catchments
Explaining changes in rainfall–runoff relationships during and after Australia's Millennium Drought: a community perspective
Three hypotheses on changing river flood hazards
A multivariate-driven approach for disentangling the reduction in near-natural Iberian water resources post-1980
Hydrology and riparian forests drive carbon and nitrogen supply and DOC : NO3− stoichiometry along a headwater Mediterranean stream
Event controls on intermittent streamflow in a temperate climate
Inclusion of flood diversion canal operation in the H08 hydrological model with a case study from the Chao Phraya River basin: model development and validation
Flood generation: process patterns from the raindrop to the ocean
Use of streamflow indices to identify the catchment drivers of hydrographs
Theoretical and empirical evidence against the Budyko catchment trajectory conjecture
Spatial distribution of groundwater recharge, based on regionalised soil moisture models in Wadi Natuf karst aquifers, Palestine
Barriers to mainstream adoption of catchment-wide natural flood management: a transdisciplinary problem-framing study of delivery practice
Low hydrological connectivity after summer drought inhibits DOC export in a forested headwater catchment
Rainbow color map distorts and misleads research in hydrology – guidance for better visualizations and science communication
Attribution of growing season evapotranspiration variability considering snowmelt and vegetation changes in the arid alpine basins
Event and seasonal hydrologic connectivity patterns in an agricultural headwater catchment
Exploring the role of hydrological pathways in modulating multi-annual climate teleconnection periodicities from UK rainfall to streamflow
Technical note: “Bit by bit”: a practical and general approach for evaluating model computational complexity vs. model performance
Hillslope and groundwater contributions to streamflow in a Rocky Mountain watershed underlain by glacial till and fractured sedimentary bedrock
A framework for seasonal variations of hydrological model parameters: impact on model results and response to dynamic catchment characteristics
Hydrology and beyond: the scientific work of August Colding revisited
The influence of a prolonged meteorological drought on catchment water storage capacity: a hydrological-model perspective
Hydrological and runoff formation processes based on isotope tracing during ablation period in the source regions of Yangtze River
Importance of snowmelt contribution to seasonal runoff and summer low flows in Czechia
Concentration–discharge relationships vary among hydrological events, reflecting differences in event characteristics
Recession analysis revisited: impacts of climate on parameter estimation
Understanding the effects of climate warming on streamflow and active groundwater storage in an alpine catchment: the upper Lhasa River
Guta Wakbulcho Abeshu, Hong-Yi Li, Mingjie Shi, and L. Ruby Leung
Hydrol. Earth Syst. Sci., 29, 1847–1864, https://doi.org/10.5194/hess-29-1847-2025, https://doi.org/10.5194/hess-29-1847-2025, 2025
Short summary
Short summary
This study examined how water availability, climate dryness, and plant productivity interact at the catchment scale. Using various indices and statistical methods, we found a 0–2-month lag in these interactions. Strong correlations during peak-productivity months were observed, with a notable hysteresis effect in vegetation response to changes in water availability and climate dryness. The findings help better understand catchment responses to climate variability.
Wouter R. Berghuijs, Ross A. Woods, Bailey J. Anderson, Anna Luisa Hemshorn de Sánchez, and Markus Hrachowitz
Hydrol. Earth Syst. Sci., 29, 1319–1333, https://doi.org/10.5194/hess-29-1319-2025, https://doi.org/10.5194/hess-29-1319-2025, 2025
Short summary
Short summary
Water balances of catchments will often strongly depend on their state in the recent past, but such memory effects may persist at annual timescales. We use global data sets to show that annual memory is typically absent in precipitation but strong in terrestrial water stores and also present in evaporation and streamflow (including low flows and floods). Our experiments show that hysteretic models provide behaviour that is consistent with these observed memory behaviours.
Xinyao Zhou, Zhuping Sheng, Kiril Manevski, Rongtian Zhao, Qingzhou Zhang, Yanmin Yang, Shumin Han, Jinghong Liu, and Yonghui Yang
Hydrol. Earth Syst. Sci., 29, 159–177, https://doi.org/10.5194/hess-29-159-2025, https://doi.org/10.5194/hess-29-159-2025, 2025
Short summary
Short summary
Conventional hydrological models erratically replicate slow hydrological dynamics, necessitating model modification and paradigm shift in hydrological science. The system dynamics approach successfully explains patterns of slow hydrological behaviors at inter-annual and decadal scales by dividing a hydrological system into different hierarchies and building endogenous linking structure among stocks. In spite of the simplicity, it holds potential to integrate hydrological behaviors across scales.
Julia L. A. Knapp, Wouter R. Berghuijs, Marius G. Floriancic, and James W. Kirchner
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2024-371, https://doi.org/10.5194/hess-2024-371, 2024
Revised manuscript accepted for HESS
Short summary
Short summary
This study explores how streams react to rain and how water travels through the landscape to reach them, two processes rarely studied together. Using detailed data from two temperate areas, it shows that streams respond to rain much faster than rainwater travels to them. Wetter conditions lead to stronger runoff by releasing older stored water, while heavy rainfall moves newer rainwater to streams faster. These findings offer new insights into how water moves through the environment.
James W. Kirchner
Hydrol. Earth Syst. Sci., 28, 4427–4454, https://doi.org/10.5194/hess-28-4427-2024, https://doi.org/10.5194/hess-28-4427-2024, 2024
Short summary
Short summary
Here, I present a new way to quantify how streamflow responds to rainfall across a range of timescales. This approach can estimate how different rainfall intensities affect streamflow. It can also quantify how runoff response to rainfall varies, depending on how wet the landscape already is before the rain falls. This may help us to understand processes and landscape properties that regulate streamflow and to assess the susceptibility of different landscapes to flooding.
Arsh Grewal, Erin M. Nicholls, and Sean K. Carey
EGUsphere, https://doi.org/10.5194/egusphere-2024-2645, https://doi.org/10.5194/egusphere-2024-2645, 2024
Short summary
Short summary
Stream chemistry in permafrost watersheds is highly seasonal. This variability can be driven by the seasonal thawing of the active layer (the layer of soil above the permafrost that thaws each year) or by streamflow (streamflow is typically highest during snowmelt). In this paper, we disentangle the influence of active layer thaw and streamflow on the seasonality of stream chemistry. We found that topography and the extent of permafrost are key factors controlling the degree of this seasonality.
Yulong Zhu, Yang Zhou, Xiaorong Xu, Changqing Meng, and Yuankun Wang
Hydrol. Earth Syst. Sci., 28, 4251–4261, https://doi.org/10.5194/hess-28-4251-2024, https://doi.org/10.5194/hess-28-4251-2024, 2024
Short summary
Short summary
A timely local flood forecast is an effective way to reduce casualties and economic losses. The current theoretical or numerical models play an important role in local flood forecasting. However, they still cannot bridge the contradiction between high calculation accuracy, high calculation efficiency, and simple operability. Therefore, this paper expects to propose a new flood forecasting model with higher computational efficiency and simpler operation.
Zhen Cui and Fuqiang Tian
EGUsphere, https://doi.org/10.5194/egusphere-2024-2177, https://doi.org/10.5194/egusphere-2024-2177, 2024
Short summary
Short summary
This study investigates stormflow patterns in a forested watershed in North China, revealing that delayed stormflow is influenced by soil water content and groundwater levels. When soil moisture exceeds its storage capacity, excess water recharges groundwater, which then flows into streams more slowly. As groundwater levels rise, they enhance water movement and connectivity, causing a delayed stormflow peak to merge with the direct stormflow peak.
Daniel Klotz, Martin Gauch, Frederik Kratzert, Grey Nearing, and Jakob Zscheischler
Hydrol. Earth Syst. Sci., 28, 3665–3673, https://doi.org/10.5194/hess-28-3665-2024, https://doi.org/10.5194/hess-28-3665-2024, 2024
Short summary
Short summary
The evaluation of model performance is essential for hydrological modeling. Using performance criteria requires a deep understanding of their properties. We focus on a counterintuitive aspect of the Nash–Sutcliffe efficiency (NSE) and show that if we divide the data into multiple parts, the overall performance can be higher than all the evaluations of the subsets. Although this follows from the definition of the NSE, the resulting behavior can have unintended consequences in practice.
Zhen Cui, Fuqiang Tian, Zilong Zhao, Zitong Xu, Yongjie Duan, Jie Wen, and Mohd Yawar Ali Khan
Hydrol. Earth Syst. Sci., 28, 3613–3632, https://doi.org/10.5194/hess-28-3613-2024, https://doi.org/10.5194/hess-28-3613-2024, 2024
Short summary
Short summary
We investigated the response characteristics and occurrence conditions of bimodal hydrographs using 10 years of hydrometric and isotope data in a semi-humid forested watershed in north China. Our findings indicate that bimodal hydrographs occur when the combined total of the event rainfall and antecedent soil moisture index exceeds 200 mm. Additionally, we determined that delayed stormflow is primarily contributed to by shallow groundwater.
Athanasios Tsiokanos, Martine Rutten, Ruud J. van der Ent, and Remko Uijlenhoet
Hydrol. Earth Syst. Sci., 28, 3327–3345, https://doi.org/10.5194/hess-28-3327-2024, https://doi.org/10.5194/hess-28-3327-2024, 2024
Short summary
Short summary
We focus on past high-flow events to find flood drivers in the Geul. We also explore flood drivers’ trends across various timescales and develop a new method to detect the main direction of a trend. Our results show that extreme 24 h precipitation alone is typically insufficient to cause floods. The combination of extreme rainfall and wet initial conditions determines the chance of flooding. Precipitation that leads to floods increases in winter, whereas no consistent trends are found in summer.
Soohyun Yang, Kwanghun Choi, and Kyungrock Paik
Hydrol. Earth Syst. Sci., 28, 3119–3132, https://doi.org/10.5194/hess-28-3119-2024, https://doi.org/10.5194/hess-28-3119-2024, 2024
Short summary
Short summary
In extracting a river network from a digital elevation model, an arbitrary pruning area should be specified. As this value grows, the apparent drainage density is reduced following a power function. This reflects the fractal topographic nature. We prove this relationship related to the known power law in the exceedance probability distribution of drainage area. The power-law exponent is expressed with fractal dimensions. Our findings are supported by analysis of 14 real river networks.
Karl Auerswald, Juergen Geist, John N. Quinton, and Peter Fiener
EGUsphere, https://doi.org/10.5194/egusphere-2024-1702, https://doi.org/10.5194/egusphere-2024-1702, 2024
Short summary
Short summary
Floods, droughts, and heatwaves are increasing globally. This is often attributed to CO2-driven climate change. However, at the global scale, CO2-driven climate change neither reduces precipitation nor adequately explains droughts. Land-use change, particularly soil sealing, compaction, and drainage, are likely more significant for water losses by runoff leading to flooding and water scarcity and are therefore an important part the solution to mitigate floods, droughts, and heatwaves.
Matthias Sprenger, Rosemary W. H. Carroll, David Marchetti, Carleton Bern, Harsh Beria, Wendy Brown, Alexander Newman, Curtis Beutler, and Kenneth H. Williams
Hydrol. Earth Syst. Sci., 28, 1711–1723, https://doi.org/10.5194/hess-28-1711-2024, https://doi.org/10.5194/hess-28-1711-2024, 2024
Short summary
Short summary
Stable isotopes of water (described as d-excess) in mountain snowpack can be used to infer proportions of high-elevation snowmelt in stream water. In a Colorado River headwater catchment, nearly half of the water during peak streamflow is derived from melted snow at elevations greater than 3200 m. High-elevation snowpack contributions were higher for years with lower snowpack and warmer spring temperatures. Thus, we suggest that d-excess could serve to assess high-elevation snowpack changes.
Bailey J. Anderson, Manuela I. Brunner, Louise J. Slater, and Simon J. Dadson
Hydrol. Earth Syst. Sci., 28, 1567–1583, https://doi.org/10.5194/hess-28-1567-2024, https://doi.org/10.5194/hess-28-1567-2024, 2024
Short summary
Short summary
Elasticityrefers to how much the amount of water in a river changes with precipitation. We usually calculate this using average streamflow values; however, the amount of water within rivers is also dependent on stored water sources. Here, we look at how elasticity varies across the streamflow distribution and show that not only do low and high streamflows respond differently to precipitation change, but also these differences vary with water storage availability.
Danny Croghan, Pertti Ala-Aho, Jeffrey Welker, Kaisa-Riikka Mustonen, Kieran Khamis, David M. Hannah, Jussi Vuorenmaa, Bjørn Kløve, and Hannu Marttila
Hydrol. Earth Syst. Sci., 28, 1055–1070, https://doi.org/10.5194/hess-28-1055-2024, https://doi.org/10.5194/hess-28-1055-2024, 2024
Short summary
Short summary
The transport of dissolved organic carbon (DOC) from land into streams is changing due to climate change. We used a multi-year dataset of DOC and predictors of DOC in a subarctic stream to find out how transport of DOC varied between seasons and between years. We found that the way DOC is transported varied strongly seasonally, but year-to-year differences were less apparent. We conclude that the mechanisms of transport show a higher degree of interannual consistency than previously thought.
Jia Qin, Yongjian Ding, Faxiang Shi, Junhao Cui, Yaping Chang, Tianding Han, and Qiudong Zhao
Hydrol. Earth Syst. Sci., 28, 973–987, https://doi.org/10.5194/hess-28-973-2024, https://doi.org/10.5194/hess-28-973-2024, 2024
Short summary
Short summary
The linkage between the seasonal hydrothermal change of active layer, suprapermafrost groundwater, and surface runoff, which has been regarded as a “black box” in hydrological analyses and simulations, is a bottleneck problem in permafrost hydrological studies. Based on field observations, this study identifies seasonal variations and causes of suprapermafrost groundwater. The linkages and framework of watershed hydrology responding to the freeze–thaw of the active layer also are explored.
Francesc Gallart, Sebastián González-Fuentes, and Pilar Llorens
Hydrol. Earth Syst. Sci., 28, 229–239, https://doi.org/10.5194/hess-28-229-2024, https://doi.org/10.5194/hess-28-229-2024, 2024
Short summary
Short summary
Normally, lighter oxygen and hydrogen isotopes are preferably evaporated from a water body, which becomes enriched in heavy isotopes. However, we observed that, in a water body subject to prolonged evaporation, some periods of heavy isotope depletion instead of enrichment happened. Furthermore, the usual models that describe the isotopy of evaporating waters may be in error if the atmospheric conditions of temperature and relative humidity are time-averaged instead of evaporation flux-weighted.
Guotao Zhang, Peng Cui, Carlo Gualtieri, Nazir Ahmed Bazai, Xueqin Zhang, and Zhengtao Zhang
Hydrol. Earth Syst. Sci., 27, 3005–3020, https://doi.org/10.5194/hess-27-3005-2023, https://doi.org/10.5194/hess-27-3005-2023, 2023
Short summary
Short summary
This study used identified stormflow thresholds as a diagnostic tool to characterize abrupt variations in catchment emergent patterns pre- and post-earthquake. Earthquake-induced landslides with spatial heterogeneity and temporally undulating recovery increase the hydrologic nonstationary; thus, large post-earthquake floods are more likely to occur. This study contributes to mitigation and adaptive strategies for unpredictable hydrologic regimes triggered by abrupt natural disturbances.
Hongkai Gao, Fabrizio Fenicia, and Hubert H. G. Savenije
Hydrol. Earth Syst. Sci., 27, 2607–2620, https://doi.org/10.5194/hess-27-2607-2023, https://doi.org/10.5194/hess-27-2607-2023, 2023
Short summary
Short summary
It is a deeply rooted perception that soil is key in hydrology. In this paper, we argue that it is the ecosystem, not the soil, that is in control of hydrology. Firstly, in nature, the dominant flow mechanism is preferential, which is not particularly related to soil properties. Secondly, the ecosystem, not the soil, determines the land–surface water balance and hydrological processes. Moving from a soil- to ecosystem-centred perspective allows more realistic and simpler hydrological models.
Daniel T. Myers, Darren L. Ficklin, and Scott M. Robeson
Hydrol. Earth Syst. Sci., 27, 1755–1770, https://doi.org/10.5194/hess-27-1755-2023, https://doi.org/10.5194/hess-27-1755-2023, 2023
Short summary
Short summary
We projected climate change impacts to rain-on-snow (ROS) melt events in the Great Lakes Basin. Decreases in snowpack limit future ROS melt. Areas with mean winter/spring air temperatures near freezing are most sensitive to ROS changes. The projected proportion of total monthly snowmelt from ROS decreases. The timing for ROS melt is projected to be 2 weeks earlier by the mid-21st century and affects spring streamflow. This could affect freshwater resources management.
Sarah A. Bourke, Margaret Shanafield, Paul Hedley, Sarah Chapman, and Shawan Dogramaci
Hydrol. Earth Syst. Sci., 27, 809–836, https://doi.org/10.5194/hess-27-809-2023, https://doi.org/10.5194/hess-27-809-2023, 2023
Short summary
Short summary
Here we present a hydrological framework for understanding the mechanisms supporting the persistence of water in pools along non-perennial rivers. Pools may collect water after rainfall events, be supported by water stored within the river channel sediments, or receive inflows from regional groundwater. These hydraulic mechanisms can be identified using a range of diagnostic tools (critiqued herein). We then apply this framework in north-west Australia to demonstrate its value.
Louisa D. Oldham, Jim Freer, Gemma Coxon, Nicholas Howden, John P. Bloomfield, and Christopher Jackson
Hydrol. Earth Syst. Sci., 27, 761–781, https://doi.org/10.5194/hess-27-761-2023, https://doi.org/10.5194/hess-27-761-2023, 2023
Short summary
Short summary
Water can move between river catchments via the subsurface, termed intercatchment groundwater flow (IGF). We show how a perceptual model of IGF can be developed with relatively simple geological interpretation and data requirements. We find that IGF dynamics vary in space, correlated to the dominant underlying geology. We recommend that IGF
loss functionsmay be used in conceptual rainfall–runoff models but should be supported by perceptualisation of IGF processes and connectivities.
Carolin Winter, Tam V. Nguyen, Andreas Musolff, Stefanie R. Lutz, Michael Rode, Rohini Kumar, and Jan H. Fleckenstein
Hydrol. Earth Syst. Sci., 27, 303–318, https://doi.org/10.5194/hess-27-303-2023, https://doi.org/10.5194/hess-27-303-2023, 2023
Short summary
Short summary
The increasing frequency of severe and prolonged droughts threatens our freshwater resources. While we understand drought impacts on water quantity, its effects on water quality remain largely unknown. Here, we studied the impact of the unprecedented 2018–2019 drought in Central Europe on nitrate export in a heterogeneous mesoscale catchment in Germany. We show that severe drought can reduce a catchment's capacity to retain nitrogen, intensifying the internal pollution and export of nitrate.
Keirnan Fowler, Murray Peel, Margarita Saft, Tim J. Peterson, Andrew Western, Lawrence Band, Cuan Petheram, Sandra Dharmadi, Kim Seong Tan, Lu Zhang, Patrick Lane, Anthony Kiem, Lucy Marshall, Anne Griebel, Belinda E. Medlyn, Dongryeol Ryu, Giancarlo Bonotto, Conrad Wasko, Anna Ukkola, Clare Stephens, Andrew Frost, Hansini Gardiya Weligamage, Patricia Saco, Hongxing Zheng, Francis Chiew, Edoardo Daly, Glen Walker, R. Willem Vervoort, Justin Hughes, Luca Trotter, Brad Neal, Ian Cartwright, and Rory Nathan
Hydrol. Earth Syst. Sci., 26, 6073–6120, https://doi.org/10.5194/hess-26-6073-2022, https://doi.org/10.5194/hess-26-6073-2022, 2022
Short summary
Short summary
Recently, we have seen multi-year droughts tending to cause shifts in the relationship between rainfall and streamflow. In shifted catchments that have not recovered, an average rainfall year produces less streamflow today than it did pre-drought. We take a multi-disciplinary approach to understand why these shifts occur, focusing on Australia's over-10-year Millennium Drought. We evaluate multiple hypotheses against evidence, with particular focus on the key role of groundwater processes.
Günter Blöschl
Hydrol. Earth Syst. Sci., 26, 5015–5033, https://doi.org/10.5194/hess-26-5015-2022, https://doi.org/10.5194/hess-26-5015-2022, 2022
Short summary
Short summary
There is serious concern that river floods are increasing. Starting from explanations discussed in public, the article addresses three hypotheses: land-use change, hydraulic structures, and climate change increase floods. This review finds that all three changes have the potential to not only increase floods, but also to reduce them. It is crucial to consider all three factors of change in flood risk management and communicate them to the general public in a nuanced way.
Amar Halifa-Marín, Miguel A. Torres-Vázquez, Enrique Pravia-Sarabia, Marc Lemus-Canovas, Pedro Jiménez-Guerrero, and Juan Pedro Montávez
Hydrol. Earth Syst. Sci., 26, 4251–4263, https://doi.org/10.5194/hess-26-4251-2022, https://doi.org/10.5194/hess-26-4251-2022, 2022
Short summary
Short summary
Near-natural Iberian water resources have suddenly decreased since the 1980s. These declines have been promoted by the weakening (enhancement) of wintertime precipitation (the NAOi) in the most humid areas, whereas afforestation and drought intensification have played a crucial role in semi-arid areas. Future water management would benefit from greater knowledge of North Atlantic climate variability and reforestation/afforestation processes in semi-arid catchments.
José L. J. Ledesma, Anna Lupon, Eugènia Martí, and Susana Bernal
Hydrol. Earth Syst. Sci., 26, 4209–4232, https://doi.org/10.5194/hess-26-4209-2022, https://doi.org/10.5194/hess-26-4209-2022, 2022
Short summary
Short summary
We studied a small stream located in a Mediterranean forest. Our goal was to understand how stream flow and the presence of riparian forests, which grow in flat banks near the stream, influence the availability of food for aquatic microorganisms. High flows were associated with higher amounts of food because rainfall episodes transfer it from the surrounding sources, particularly riparian forests, to the stream. Understanding how ecosystems work is essential to better manage natural resources.
Nils Hinrich Kaplan, Theresa Blume, and Markus Weiler
Hydrol. Earth Syst. Sci., 26, 2671–2696, https://doi.org/10.5194/hess-26-2671-2022, https://doi.org/10.5194/hess-26-2671-2022, 2022
Short summary
Short summary
This study is analyses how characteristics of precipitation events and soil moisture and temperature dynamics during these events can be used to model the associated streamflow responses in intermittent streams. The models are used to identify differences between the dominant controls of streamflow intermittency in three distinct geologies of the Attert catchment, Luxembourg. Overall, soil moisture was found to be the most important control of intermittent streamflow in all geologies.
Saritha Padiyedath Gopalan, Adisorn Champathong, Thada Sukhapunnaphan, Shinichiro Nakamura, and Naota Hanasaki
Hydrol. Earth Syst. Sci., 26, 2541–2560, https://doi.org/10.5194/hess-26-2541-2022, https://doi.org/10.5194/hess-26-2541-2022, 2022
Short summary
Short summary
The modelling of diversion canals using hydrological models is important because they play crucial roles in water management. Therefore, we developed a simplified canal diversion scheme and implemented it into the H08 global hydrological model. The developed diversion scheme was validated in the Chao Phraya River basin, Thailand. Region-specific validation results revealed that the H08 model with the diversion scheme could effectively simulate the observed flood diversion pattern in the basin.
Günter Blöschl
Hydrol. Earth Syst. Sci., 26, 2469–2480, https://doi.org/10.5194/hess-26-2469-2022, https://doi.org/10.5194/hess-26-2469-2022, 2022
Short summary
Short summary
Sound understanding of how floods come about allows for the development of more reliable flood management tools that assist in mitigating their negative impacts. This article reviews river flood generation processes and flow paths across space scales, starting from water movement in the soil pores and moving up to hillslopes, catchments, regions and entire continents. To assist model development, there is a need to learn from observed patterns of flood generation processes at all spatial scales.
Jeenu Mathai and Pradeep P. Mujumdar
Hydrol. Earth Syst. Sci., 26, 2019–2033, https://doi.org/10.5194/hess-26-2019-2022, https://doi.org/10.5194/hess-26-2019-2022, 2022
Short summary
Short summary
With availability of large samples of data in catchments, it is necessary to develop indices that describe the streamflow processes. This paper describes new indices applicable for the rising and falling limbs of streamflow hydrographs. The indices provide insights into the drivers of the hydrographs. The novelty of the work is on differentiating hydrographs by their time irreversibility property and offering an alternative way to recognize primary drivers of streamflow hydrographs.
Nathan G. F. Reaver, David A. Kaplan, Harald Klammler, and James W. Jawitz
Hydrol. Earth Syst. Sci., 26, 1507–1525, https://doi.org/10.5194/hess-26-1507-2022, https://doi.org/10.5194/hess-26-1507-2022, 2022
Short summary
Short summary
The Budyko curve emerges globally from the behavior of multiple catchments. Single-parameter Budyko equations extrapolate the curve concept to individual catchments, interpreting curves and parameters as representing climatic and biophysical impacts on water availability, respectively. We tested these two key components theoretically and empirically, finding that catchments are not required to follow Budyko curves and usually do not, implying the parametric framework lacks predictive ability.
Clemens Messerschmid and Amjad Aliewi
Hydrol. Earth Syst. Sci., 26, 1043–1061, https://doi.org/10.5194/hess-26-1043-2022, https://doi.org/10.5194/hess-26-1043-2022, 2022
Short summary
Short summary
Temporal distribution of groundwater recharge has been widely studied; yet, much less attention has been paid to its spatial distribution. Based on a previous study of field-measured and modelled formation-specific recharge in the Mediterranean, this paper differentiates annual recharge coefficients in a novel approach and basin classification framework for physical features such as lithology, soil and LU/LC characteristics, applicable also in other previously ungauged basins around the world.
Thea Wingfield, Neil Macdonald, Kimberley Peters, and Jack Spees
Hydrol. Earth Syst. Sci., 25, 6239–6259, https://doi.org/10.5194/hess-25-6239-2021, https://doi.org/10.5194/hess-25-6239-2021, 2021
Short summary
Short summary
Human activities are causing greater and more frequent floods. Natural flood management (NFM) uses processes of the water cycle to slow the flow of rainwater, bringing together land and water management. Despite NFM's environmental and social benefits, it is yet to be widely adopted. Two environmental practitioner groups collaborated to produce a picture of the barriers to delivery, showing that there is a perceived lack of support from government and the public for NFM.
Katharina Blaurock, Burkhard Beudert, Benjamin S. Gilfedder, Jan H. Fleckenstein, Stefan Peiffer, and Luisa Hopp
Hydrol. Earth Syst. Sci., 25, 5133–5151, https://doi.org/10.5194/hess-25-5133-2021, https://doi.org/10.5194/hess-25-5133-2021, 2021
Short summary
Short summary
Dissolved organic carbon (DOC) is an important part of the global carbon cycle with regards to carbon storage, greenhouse gas emissions and drinking water treatment. In this study, we compared DOC export of a small, forested catchment during precipitation events after dry and wet preconditions. We found that the DOC export from areas that are usually important for DOC export was inhibited after long drought periods.
Michael Stoelzle and Lina Stein
Hydrol. Earth Syst. Sci., 25, 4549–4565, https://doi.org/10.5194/hess-25-4549-2021, https://doi.org/10.5194/hess-25-4549-2021, 2021
Short summary
Short summary
We found with a scientific paper survey (~ 1000 papers) that 45 % of the papers used rainbow color maps or red–green visualizations. Those rainbow visualizations, although attracting the media's attention, will not be accessible for up to 10 % of people due to color vision deficiency. The rainbow color map distorts and misleads scientific communication. The study gives guidance on how to avoid, improve and trust color and how the flaws of the rainbow color map should be communicated in science.
Tingting Ning, Zhi Li, Qi Feng, Zongxing Li, and Yanyan Qin
Hydrol. Earth Syst. Sci., 25, 3455–3469, https://doi.org/10.5194/hess-25-3455-2021, https://doi.org/10.5194/hess-25-3455-2021, 2021
Short summary
Short summary
Previous studies decomposed ET variance in precipitation, potential ET, and total water storage changes based on Budyko equations. However, the effects of snowmelt and vegetation changes have not been incorporated in snow-dependent basins. We thus extended this method in arid alpine basins of northwest China and found that ET variance is primarily controlled by rainfall, followed by coupled rainfall and vegetation. The out-of-phase seasonality between rainfall and snowmelt weaken ET variance.
Lovrenc Pavlin, Borbála Széles, Peter Strauss, Alfred Paul Blaschke, and Günter Blöschl
Hydrol. Earth Syst. Sci., 25, 2327–2352, https://doi.org/10.5194/hess-25-2327-2021, https://doi.org/10.5194/hess-25-2327-2021, 2021
Short summary
Short summary
We compared the dynamics of streamflow, groundwater and soil moisture to investigate how different parts of an agricultural catchment in Lower Austria are connected. Groundwater is best connected around the stream and worse uphill, where groundwater is deeper. Soil moisture connectivity increases with increasing catchment wetness but is not influenced by spatial position in the catchment. Groundwater is more connected to the stream on the seasonal scale compared to the event scale.
William Rust, Mark Cuthbert, John Bloomfield, Ron Corstanje, Nicholas Howden, and Ian Holman
Hydrol. Earth Syst. Sci., 25, 2223–2237, https://doi.org/10.5194/hess-25-2223-2021, https://doi.org/10.5194/hess-25-2223-2021, 2021
Short summary
Short summary
In this paper, we find evidence for the cyclical behaviour (on a 7-year basis) in UK streamflow records that match the main cycle of the North Atlantic Oscillation. Furthermore, we find that the strength of these 7-year cycles in streamflow is dependent on proportional contributions from groundwater and the response times of the underlying groundwater systems. This may allow for improvements to water management practices through better understanding of long-term streamflow behaviour.
Elnaz Azmi, Uwe Ehret, Steven V. Weijs, Benjamin L. Ruddell, and Rui A. P. Perdigão
Hydrol. Earth Syst. Sci., 25, 1103–1115, https://doi.org/10.5194/hess-25-1103-2021, https://doi.org/10.5194/hess-25-1103-2021, 2021
Short summary
Short summary
Computer models should be as simple as possible but not simpler. Simplicity refers to the length of the model and the effort it takes the model to generate its output. Here we present a practical technique for measuring the latter by the number of memory visits during model execution by
Strace, a troubleshooting and monitoring program. The advantage of this approach is that it can be applied to any computer-based model, which facilitates model intercomparison.
Sheena A. Spencer, Axel E. Anderson, Uldis Silins, and Adrian L. Collins
Hydrol. Earth Syst. Sci., 25, 237–255, https://doi.org/10.5194/hess-25-237-2021, https://doi.org/10.5194/hess-25-237-2021, 2021
Short summary
Short summary
We used unique chemical signatures of precipitation, hillslope soil water, and groundwater sources of streamflow to explore seasonal variation in runoff generation in a snow-dominated mountain watershed underlain by glacial till and permeable bedrock. Reacted hillslope water reached the stream first at the onset of snowmelt, followed by a dilution effect by snowmelt from May to June. Groundwater and riparian water were important sources later in the summer. Till created complex subsurface flow.
Tian Lan, Kairong Lin, Chong-Yu Xu, Zhiyong Liu, and Huayang Cai
Hydrol. Earth Syst. Sci., 24, 5859–5874, https://doi.org/10.5194/hess-24-5859-2020, https://doi.org/10.5194/hess-24-5859-2020, 2020
Dan Rosbjerg
Hydrol. Earth Syst. Sci., 24, 4575–4585, https://doi.org/10.5194/hess-24-4575-2020, https://doi.org/10.5194/hess-24-4575-2020, 2020
Short summary
Short summary
August Colding contributed the first law of thermodynamics, evaporation from water and grass, steady free surfaces in conduits, the cross-sectional velocity distribution in conduits, a complete theory for the Gulf Stream, air speed in cyclones, the piezometric surface in confined aquifers, the unconfined elliptic water table in soil between drain pipes, and the wind-induced set-up in the sea during storms.
Zhengke Pan, Pan Liu, Chong-Yu Xu, Lei Cheng, Jing Tian, Shujie Cheng, and Kang Xie
Hydrol. Earth Syst. Sci., 24, 4369–4387, https://doi.org/10.5194/hess-24-4369-2020, https://doi.org/10.5194/hess-24-4369-2020, 2020
Short summary
Short summary
This study aims to identify the response of catchment water storage capacity (CWSC) to meteorological drought by examining the changes of hydrological-model parameters after drought events. This study improves our understanding of possible changes in the CWSC induced by a prolonged meteorological drought, which will help improve our ability to simulate the hydrological system under climate change.
Zong-Jie Li, Zong-Xing Li, Ling-Ling Song, Juan Gui, Jian Xue, Bai Juan Zhang, and Wen De Gao
Hydrol. Earth Syst. Sci., 24, 4169–4187, https://doi.org/10.5194/hess-24-4169-2020, https://doi.org/10.5194/hess-24-4169-2020, 2020
Short summary
Short summary
This study mainly explores the hydraulic relations, recharge–drainage relations and their transformation paths, and the processes of each water body. It determines the composition of runoff, quantifies the contribution of each runoff component to different types of tributaries, and analyzes the hydrological effects of the temporal and spatial variation in runoff components. More importantly, we discuss the hydrological significance of permafrost and hydrological processes.
Michal Jenicek and Ondrej Ledvinka
Hydrol. Earth Syst. Sci., 24, 3475–3491, https://doi.org/10.5194/hess-24-3475-2020, https://doi.org/10.5194/hess-24-3475-2020, 2020
Short summary
Short summary
Changes in snow affect the runoff seasonality, including summer low flows. Here we analyse this effect in 59 mountain catchments in Czechia. We show that snow is more effective in generating runoff compared to rain. Snow-poor years generated lower groundwater recharge than snow-rich years, which resulted in higher deficit volumes in summer. The lower recharge and runoff in the case of a snowfall-to-rain transition due to air temperature increase might be critical for water supply in the future.
Julia L. A. Knapp, Jana von Freyberg, Bjørn Studer, Leonie Kiewiet, and James W. Kirchner
Hydrol. Earth Syst. Sci., 24, 2561–2576, https://doi.org/10.5194/hess-24-2561-2020, https://doi.org/10.5194/hess-24-2561-2020, 2020
Short summary
Short summary
Changes of stream water chemistry in response to discharge changes provide important insights into the storage and release of water from the catchment. Here we investigate the variability in concentration–discharge relationships among different solutes and hydrologic events and relate it to catchment conditions and dominant water sources.
Elizabeth R. Jachens, David E. Rupp, Clément Roques, and John S. Selker
Hydrol. Earth Syst. Sci., 24, 1159–1170, https://doi.org/10.5194/hess-24-1159-2020, https://doi.org/10.5194/hess-24-1159-2020, 2020
Short summary
Short summary
Recession analysis uses the receding streamflow following precipitation events to estimate watershed-average properties. Two methods for recession analysis use recession events individually or all events collectively. Using synthetic case studies, this paper shows that analyzing recessions collectively produces flawed interpretations. Moving forward, recession analysis using individual recessions should be used to describe the average and variability of watershed behavior.
Lu Lin, Man Gao, Jintao Liu, Jiarong Wang, Shuhong Wang, Xi Chen, and Hu Liu
Hydrol. Earth Syst. Sci., 24, 1145–1157, https://doi.org/10.5194/hess-24-1145-2020, https://doi.org/10.5194/hess-24-1145-2020, 2020
Short summary
Short summary
In this paper, recession flow analysis – assuming nonlinearized outflow from aquifers into streams – was used to quantify active groundwater storage in a headwater catchment with high glacierization and large-scale frozen ground on the Tibetan Plateau. Hence, this work provides a perspective to clarify the impact of glacial retreat and frozen ground degradation due to climate change on hydrological processes.
Cited articles
Ali, G., Tetzlaff, D., Soulsby, C., McDonnell, J. J., and Capell, R.: A comparison of similarity indices for catchment classification using a cross-regional dataset, Adv. Water Resour., 40, 11–22, https://doi.org/10.1016/j.advwatres.2012.01.008, 2012.
Barthold, F. K. and Woods, R. A.: Stormflow generation: A meta-analysis of field evidence from small, forested catchments, Water Resour. Res., 51, 3730–3753, https://doi.org/10.1002/2014WR016221, 2015.
Bayerisches Landesamt für Umwelt: Hochwassernachrichtendienst Bayern, available at: http://www.hnd.bayern.de/, 2017.
Bergstroem, S.: Development and application of a conceptual runoff model for Scandinavian catchments, Tech. rep., Swedish Meteorological and Hydrological Institute (SMHI), Report RHO 7, Norrkoping, 1976.
Beven, K. and Germann, P.: Macropores and water flow in soils revisited, Water Resour. Res., 49, 3071–3092, https://doi.org/10.1002/wrcr.20156, 2013.
Beven, K. and Kirkby, M. J.: A physically based, variable contributing area model of basin hydrology, Hydrological Sciences Bulletin, 24, 43–69, 1979.
BGR and SGD: Hydrogeological spatial structure of Germany (HYRAUM). Digital map data v3.2. German Federal States Geological Surveys (SGD) and Federal Institute for Geosciences and Natural Resources (BGR), 2015.
Black, P. E.: Watershed Functions, J. Am. Water Resour. As., 33, 1–11, https://doi.org/10.1111/j.1752-1688.1997.tb04077.x, 1997.
Blöschl, G. and Sivapalan, M.: Scale issues in hydrological modelling: A review, Hydrol. Process., 9, 251–290, https://doi.org/10.1002/hyp.3360090305, 1995.
Blöschl, G., Sivapalan, M., Wagener, T., Viglione, A., and Savenije, H. H. G.: Runoff prediction in ungauged basins: synthesis across processes, places and scales, Cambridge University Press, Cambridge, 2013.
Boorman, D. B., Hollis, J. M., and Lilly, A.: Hydrology of soil types: a hydrologically-based classification of the soils of United Kingdom., Tech. Rep. 126, Institut of Hydrology, Wallingford, 1995.
Capell, R., Tetzlaff, D., Hartley, A. J., and Soulsby, C.: Linking metrics of hydrological function and transit times to landscape controls in a heterogeneous mesoscale catchment, Hydrol. Process., 26, 405–420, https://doi.org/10.1002/hyp.8139, 2012.
Casper, M. C., Grigoryan, G., Gronz, O., Gutjahr, O., Heinemann, G., Ley, R., and Rock, A.: Analysis of projected hydrological behavior of catchments based on signature indices, Hydrol. Earth Syst. Sci., 16, 409–421, https://doi.org/10.5194/hess-16-409-2012, 2012.
Cerdan, O., Souchère, V., Lecomte, V., Couturier, A., and Le Bissonnais, Y.: Incorporating soil surface crusting processes in an expert-based runoff model: Sealing and Transfer by Runoff and Erosion related to Agricultural Management, Catena, 46, 189–205, https://doi.org/10.1016/S0341-8162(01)00166-7, 2002.
Duan, Q., Schaake, J., Andréassian, V., Franks, S., Goteti, G., Gupta, H. V., Gusev, Y. M., Habets, F., Hall, A., Hay, L., Hogue, T., Huang, M., Leavesley, G., Liang, X., Nasonova, O. N., Noilhan, J., Oudin, L., Sorooshian, S., Wagener, T., and Wood, E. F.: Model Parameter Estimation Experiment (MOPEX): An overview of science strategy and major results from the second and third workshops, J. Hydrol., 320, 3–17, https://doi.org/10.1016/j.jhydrol.2005.07.031, 2006.
Euser, T., Winsemius, H. C., Hrachowitz, M., Fenicia, F., Uhlenbrook, S., and Savenije, H. H. G.: A framework to assess the realism of model structures using hydrological signatures, Hydrol. Earth Syst. Sci., 17, 1893–1912, https://doi.org/10.5194/hess-17-1893-2013, 2013.
Euser, T., Hrachowitz, M., Winsemius, H. C., and Savenije, H. H.: The effect of forcing and landscape distribution on performance and consistency of model structures, Hydrol. Process., 29, 3727–3743, https://doi.org/10.1002/hyp.10445, 2015.
Fogler, S. H.: Elements of Chemical Reaction Engineering, Prentice Hall, New Jersey, 1999.
Gassmann, M., Stamm, C., Olsson, O., Lange, J., Kümmerer, K., and Weiler, M.: Model-based estimation of pesticides and transformation products and their export pathways in a headwater catchment, Hydrol. Earth Syst. Sci., 17, 5213–5228, https://doi.org/10.5194/hess-17-5213-2013, 2013.
Graeff, T., Zehe, E., Blume, T., Francke, T., and Schröder, B.: Predicting event response in a nested catchment with generalized linear models and a distributed watershed model, Hydrol. Process., 26, 3749–3769, https://doi.org/10.1002/hyp.8463, 2012.
Gupta, H. V., Wagener, T., and Liu, Y.: Reconciling theory with observations: Elements of a diagnostic approach to model evaluation, Hydrol. Process., 22, 3802–3813, https://doi.org/10.1002/hyp.6989, 2008.
Hartwich, R., Behrens, J., Eckelmann, W., Haase, G., Richter, A., Roeschmann, G., and Schmidt, R.: Bodenübersichtskarte der Bundesrepublik Deutschland 1 : 1 000 000, Karte mit Erläuterungen, Textlegende und Leitprofilen, 1995.
Hellebrand, H., Van Den Bos, R., Hoffmann, L., Juilleret, J., and Pfister, L.: The potential of winter stormflow coefficients for hydrological regionalization purposes in poorly gauged basins of the middle Rhine region, Hydrolog. Sci. J., 53, 773–788, https://doi.org/10.1623/hysj.53.4.773, 2008.
Hillel, D.: Introduction to Environmental Soil Physics, Academic Press, Elsevier, San Diego, California, 2004.
Holdridge, L. R.: Life zone ecology, Tropical Science Center, San Jose, Costa Rica, 1967.
Horton, R. E.: The role of infiltration in the hydrologic cycle, Transactions of the American Geophysical Union, 14, 446–460, 1933.
Hrachowitz, M., Bohte, R., Mul, M. L., Bogaard, T. A., Savenije, H. H. G., and Uhlenbrook, S.: On the value of combined event runoff and tracer analysis to improve understanding of catchment functioning in a data-scarce semi-arid area, Hydrol. Earth Syst. Sci., 15, 2007–2024, https://doi.org/10.5194/hess-15-2007-2011, 2011.
Hrachowitz, M., Savenije, H. H. G., Bloschl, G., McDonnell, J. J., Sivapalan, M., Pomeroy, J. W., Arheimer, B., Blume, T., Clark, M. P., Ehret, U., Fenicia, F., Freer, J. E., Gelfan, A., Gupta, H. V., Hughes, D. A., Hut, R. W., Montanari, A., Pande, S., Tetzlaff, D., Troch, P. A., Uhlenbrook, S., Wagener, T., Winsemius, H. C., Woods, R. A., Zehe, E., and Cudennec, C.: A decade of Predictions in Ungauged Basins (PUB) a review, Hydrolog. Sci. J., 58, 1198–1255, https://doi.org/10.1080/02626667.2013.803183, 2013.
Jackisch, C.: Linking structure and functioning of hydrological systems. How to achieve necessary experimental and model complexity with adequate effort., PhD thesis, Institut für Wasser und Gewässerentwicklung, Bereich Hydrologie, Karlsruher Institut für Technologie (KIT), https://doi.org/10.5445/IR/1000051494, 2015.
Kenney, B. C.: Beware of spurious self-correlations!, Water Resour. Res., 18, 1041–1048, https://doi.org/10.1029/WR018i004p01041, 1982.
Kirby, M.: Hydrograph modelling strategies, in: Progress in Physical and Human Geograph, edited by: Peel, R., 69–90, Heinemann, London, 1975.
Kirchner, J. W.: Getting the right answers for the right reasons: Linking measurements, analyses, and models to advance the science of hydrology, Water Resour. Res., 42, 5 pp., https://doi.org/10.1029/2005WR004362, 2006.
Kirchner, J. W.: Catchments as simple dynamical systems: Catchment characterization, rainfall-runoff modeling, and doing hydrology backward, Water Resour. Res., 45, W02429, https://doi.org/10.1029/2008WR006912, 2009.
Klaus, J., Wetzel, C. E., Martinez-Carreras, N., Ector, L., and Pfister, L.: A tracer to bridge the scales: On the value of diatoms for tracing fast flow path connectivity from headwaters to meso-scale catchments, Hydrol. Process., 29, 5275–5289, https://doi.org/10.1002/hyp.10628, 2015.
Larsen, J. E., Sivapalan, M., Coles, N. A., and Linnet, P. E.: Similarity analysis of runoff generation processes in real-world catchments, Water Resour. Res., 30, 1641–1652, https://doi.org/10.1029/94WR00555, 1994.
Leavesley, G. H.: A mountain watershed simulation model, PhD thesis, Colorado State University, Fort Collins, 1973.
Ley, R., Casper, M. C., Hellebrand, H., and Merz, R.: Catchment classification by runoff behaviour with self-organizing maps (SOM), Hydrol. Earth Syst. Sci., 15, 2947–2962, https://doi.org/10.5194/hess-15-2947-2011, 2011.
Li, H., Sivapalan, M., and Tian, F.: Comparative diagnostic analysis of runoff generation processes in Oklahoma DMIP2 basins: The Blue River and the Illinois River, J. Hydrol., 418–419, 90–109, https://doi.org/10.1016/j.jhydrol.2010.08.005, 2012.
Lindsay, J. B.: The Whitebox Geospatial Analysis Tools project and open-access GIS, in: Proceedings of the GIS Research UK 22nd Annual Conference, p. 8, https://doi.org/10.13140/RG.2.1.1010.8962, 2014.
Loritz, R., Hassler, S. K., Jackisch, C., Allroggen, N., van Schaik, L., Wienhöfer, J., and Zehe, E.: Picturing and modeling catchments by representative hillslopes, Hydrol. Earth Syst. Sci., 21, 1225–1249, https://doi.org/10.5194/hess-21-1225-2017, 2017.
Ludwig, K. and Bremicker, M.: The Water Balance Model LARSIM, Tech. Rep. 22, Institut für Hydrologie der Universität Freiburg i.Br., 2006.
Mäkelä, A., Hari, P., Berninger, F., Hänninen, H., and Nikinmaa, E.: Acclimation of photosynthetic capacity in Scots pine to the annual cycle of temperature., Tree physiology, 24, 369–76, https://doi.org/10.1093/TREEPHYS/24.4.369, 2004.
Martínez-Carreras, N., Krein, A., Gallart, F., Iffly, J. F., Pfister, L., Hoffmann, L., and Owens, P. N.: Assessment of different colour parameters for discriminating potential suspended sediment sources and provenance: A multi-scale study in Luxembourg, Geomorphology, 118, 118–129, https://doi.org/10.1016/j.geomorph.2009.12.013, 2010.
Martínez-Carreras, N., Wetzel, C. E., Frentress, J., Ector, L., McDonnell, J. J., Hoffmann, L., and Pfister, L.: Hydrological connectivity inferred from diatom transport through the riparian-stream system, Hydrol. Earth Syst. Sci., 19, 3133–3151, https://doi.org/10.5194/hess-19-3133-2015, 2015.
Maurer, T.: Physikalisch begründete zeitkontinuierliche Modellierung des Wassertransports in kleinen ländlichen Einzugsgebieten, Phd thesis, Mitteilungen des Instituts für Hydrologie und Wasserwirtschaft, Bd. 61, Universitat Fridericiana zu Karlsruhe (TH), 1997.
McGuire, K. J., McDonnell, J. J., Weiler, M., Kendall, C., McGlynn, B. L., Welker, J. M., and Seibert, J.: The role of topography on catchment-scale water residence time, Water Resour. Res., 41, W05002, https://doi.org/10.1029/2004WR003657, 2005.
McMillan, H., Gueguen, M., Grimon, E., Woods, R., Clark, M., and Rupp, D. E.: Spatial variability of hydrological processes and model structure diagnostics in a 50 km2 catchment, Hydrol. Process., 28, 4896–4913, https://doi.org/10.1002/hyp.9988, 2014.
McMillan, H. K., Clark, M. P., Bowden, W. B., Duncan, M., and Woods, R. A.: Hydrological field data from a modeller's perspective: Part 1. Diagnostic tests for model structure, Hydrol. Process., 25, 511–522, https://doi.org/10.1002/hyp.7841, 2011.
Menzel, A., Jakobi, G., Ahas, R., Scheifinger, H., and Estrella, N.: Variations of the climatological growing season (1951–2000) in Germany compared with other countries, Int. J. Climatol., 23, 793–812, https://doi.org/10.1002/joc.915, 2003.
Merz, R., Blöschl, G., and Parajka, J.: Spatio-temporal variability of event runoff coefficients, J. Hydrol., 331, 591–604, https://doi.org/10.1016/j.jhydrol.2006.06.008, 2006.
Milly, P. C. D., Betancourt, J., Falkenmark, M., Hirsch, R. M., Kundzewicz, Z. W., Lettenmaier, D. P., and Stouffer, R. J.: Stationarity Is Dead: Whither Water Management?, Science, 319, 573–574, https://doi.org/10.1126/science.1151915, 2008.
Mualem, Y., Assouline, S., and Rohdenburg, H.: Rainfall induced soil seal (A) – A critical review of observations and models, CATENA, 17, 185–203, https://doi.org/10.1016/0341-8162(90)90008-2, 1990.
NOAA: National Weather Service River Forcast System Forecast Procedures, Tech. rep., NWS-Hydro-14, NOAA Technical Memorandum, US Department of Commerce, Washington, DC, 1972.
Oldham, C. E., Farrow, D. E., and Peiffer, S.: A generalized Damköhler number for classifying material processing in hydrological systems, Hydrol. Earth Syst. Sci., 17, 1133–1148, https://doi.org/10.5194/hess-17-1133-2013, 2013.
Oudin, L., Andreassian, V., Perrin, C., Michel, C., and Le Moine, N.: Spatial proximity, physical similarity, regression and ungaged catchments: A comparison of regionalization approaches based on 913 French catchments, Water Resour. Res., 44, W03413, https://doi.org/10.1029/2007WR006240, 2008.
Oudin, L., Kay, A., Andreassian, V., and Perrin, C.: Are seemingly physically similar catchments truly hydrologically similar?, Water Resour. Res., 46, W11558, https://doi.org/10.1029/2009wr008887, 2010.
Pearson, K.: Mathematical Contributions to the Theory of Evolution. – On a Form of Spurious Correlation Which May Arise When Indices Are Used in the Measurement of Organs, P. R. Soc. London, 60, 489–498, https://doi.org/10.1098/rspl.1896.0076, 1987.
Pelletier, J. D. and Rasmussen, C.: Geomorphically based predictive mapping of soil thickness in upland watersheds, Water Resour. Res., 45, W09417, https://doi.org/10.1029/2008WR007319, 2009.
Perry, K., Sanders, D., Granberry, D., Thomasgarrett, J., Decoteau, D., Nagata, R., Dufault, R., Deanbatal, K., and McLaurin, W.: Heat units, solar radiation and daylength as pepper harvest predictors, Agr. Forest Meteorol., 65, 197–205, https://doi.org/10.1016/0168-1923(93)90004-2, 1993.
Peschke, G., Etzenberg, C., Müller, G., Töpfer, J., and Zimmermann, S.: Das wissensbasierte System FLAB – ein Instrument zur rechnergestützten Bestimmung von Landschaftseinheiten mit gleicher Abflussbilung, Tech. rep., Internationales Hochschulinstitut Zittau, IHI-Schriften, BD. 10, Zittau, 1999.
Pfannerstill, M., Guse, B., and Fohrer, N.: Smart low flow signature metrics for an improved overall performance evaluation of hydrological models, J. Hydrol., 510, 447–458, https://doi.org/10.1016/j.jhydrol.2013.12.044, 2014.
Pfister, L., Iffly, J. F., and Hoffmann, L.: Use of regionalized stormflow coefficients with a view to hydroclimatological hazard mapping, Hydrolog. Sci. J., 47, 479–491, https://doi.org/10.1080/02626660209492948, 2002.
Pokhrel, P. and Yilmaz, K. K.: Multiple-criteria calibration of a distributed watershed model using spatial regularization and response signatures, J. Hydrol., 418, 49–60, https://doi.org/10.1016/j.jhydrol.2008.12.004, 2012.
R Core Team: R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, 2015.
Rawson, H. M. and Gomez-Macpherson, H.: Irrigated wheat – managing your crop, Food and Agriculture Organization of the United Nations (FAO), Rome, 2000.
Reaney, S. M., Bracken, L. J., and Kirkby, M. J.: The importance of surface controls on overland flow connectivity in semi-arid environments: results from a numerical experimental approach, Hydrol. Process., 28, 2116–2128, https://doi.org/10.1002/hyp.9769, 2014.
Reggiani, P., Sivapalan, M., and Majid Hassanizadeh, S.: A unifying framework for watershed thermodynamics: balance equations for mass, momentum, energy and entropy, and the second law of thermodynamics, Adv. Water Resour., 22, 367–398, https://doi.org/10.1016/S0309-1708(98)00012-8, 1998.
Reggiani, P., Sivapalan, M., and Hassanizadeh, S. M.: Conservation equations governing hillslope responses: Exploring the physical basis of water balance, Water Resour. Res., 36, 1845, https://doi.org/10.1029/2000WR900066, 2000.
Reichenau, T. G., Korres, W., Montzka, C., Fiener, P., Wilken, F., Stadler, A., Waldhoff, G., and Schneider, K.: Spatial heterogeneity of Leaf Area Index (LAI) and its temporal course on arable land: Combining field measurements, remote sensing and simulation in a Comprehensive Data Analysis Approach (CDAA), PLoS ONE, 11, 1–24, https://doi.org/10.1371/journal.pone.0158451, 2016.
Reynolds, O.: An experimental investigation of the circumstances which determine whether the motion of water shall be direct or sinuous, and of the law of resistance in parallel channels, Philos. T. R. Soc. Lond., 174, 935–982, https://doi.org/10.1098/rstl.1883.0029, 1883.
Robinson, J. S., Sivapalan, M., and Snell, J. D.: On the relative roles of hillslope processes, channel routing, and network geomorphology in the hydrologic response of natural catchments, Water Resour. Res., 31, 3089–3101, https://doi.org/10.1029/95WR01948, 1995.
Santhi, C., Allen, P. M., Muttiah, R. S., Arnold, J. G., and Tuppad, P.: Regional estimation of base flow for the conterminous United States by hydrologic landscape regions, J. Hydrol., 351, 139–153, https://doi.org/10.1016/j.jhydrol.2007.12.018, 2008.
Sawicz, K., Wagener, T., Sivapalan, M., Troch, P. A., and Carrillo, G.: Catchment classification: empirical analysis of hydrologic similarity based on catchment function in the eastern USA, Hydrol. Earth Syst. Sci., 15, 2895–2911, https://doi.org/10.5194/hess-15-2895-2011, 2011.
Sayama, T., McDonnell, J. J., Dhakal, A., and Sullivan, K.: How much water can a watershed store?, Hydrol. Process., 25, 3899–3908, https://doi.org/10.1002/hyp.8288, 2011.
Schaake, J., Duan, Q., Smith, M., and Koren, V.: Criteria to select basins for hydrologic model development and testing, 15th Conference on Hydrology (P1.8), AMS, January 9-14. Long Beach, CA, 2000.
Schaap, M. G., Leij, F. J., and van Genuchten, M. T.: Rosetta: A computer program for estimating soil hydraulic parameters with hierarchical pedotransfer functions, J. Hydrol., 251, 163–176, https://doi.org/10.1016/S0022-1694(01)00466-8, 2001.
Schaefli, B., Harman, C. J., Sivapalan, M., and Schymanski, S. J.: HESS Opinions: Hydrologic predictions in a changing environment: behavioral modeling, Hydrol. Earth Syst. Sci., 15, 635–646, https://doi.org/10.5194/hess-15-635-2011, 2011.
Scherrer, S. and Naef, F.: A decision scheme to indicate dominant hydrological flow processes on temperate grassland, Hydrol. Process., 17, 391–401, https://doi.org/10.1002/hyp.1131, 2003.
Schmocker-Fackel, P., Naef, F., and Scherrer, S.: Identifying runoff processes on the plot and catchment scale, Hydrol. Earth Syst. Sci., 11, 891–906, https://doi.org/10.5194/hess-11-891-2007, 2007.
Schulla, J.: Hydrologische Modellierung von Flussgebieten zur Abschätzung der Folgen von Klimaäderungen, Phd thesis, Zürcher Geographische Schriften, Bd. 69, ETH Zürich, https://doi.org/10.3929/ethz-a-001763261, 1997.
Seibert, S. P., Skublics, D., and Ehret, U.: The potential of coordinated reservoir operation for flood mitigation in large basins – A case study on the Bavarian Danube using coupled hydrological-hydrodynamic models, J. Hydrol., 517, 1128–1144, https://doi.org/10.1016/j.jhydrol.2014.06.048, 2014.
Seibert, S. P., Ehret, U., and Zehe, E.: Disentangling timing and amplitude errors in streamflow simulations, Hydrol. Earth Syst. Sci., 20, 3745–3763, https://doi.org/10.5194/hess-20-3745-2016, 2016a.
Seibert, S. P., Jackisch, C., Pfister, L., Ehret, U., and Zehe, E.: Exploring the interplay between state, structure and runoff behaviour of lower mesoscale catchments, Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2016-109, in review, 2016b.
Sivapalan, M.: Prediction in ungauged basins: a grand challenge for theoretical hydrology, Hydrol. Process., 17, 3163–3170, https://doi.org/10.1002/hyp.5155, 2003.
Sivapalan, M., Beven, K., and Wood, E. F.: On hydrologic similarity: 2. A scaled model of storm runoff production, Water Resour. Res., 23, 2266–2278, 1987.
Sivapalan, M., Takeuchi, K., Franks, S. W., Gupta, V., Karambiri, H., Lakshmi, W., Liang, X., McDonnell, J., Mendionde, E. M., O'Connel, P., Oki, T., Pomeroy, J. W., Schertzer, D., Uhlenbrook, S., and Zehe, E.: IAHS Decade on Predictions in Ungauged Basins (PUB), 2003-2012: shaping an exciting future for the hydrological sciences, Hydrol. Sci. J., 48, 857–880, 2003.
Solantie, R.: Daytime temperature sum - a new thermal variable describing growing season characteristics and explaining evapotranspiration, Boreal Environ. Res., 9, 319–333, 2004.
Soulsby, C., Tetzlaff, D., and Hrachowitz, M.: Are transit times useful process-based tools for flow prediction and classification in ungauged basins in montane regions?, Hydrol. Process., 24, 1685–1696, https://doi.org/10.1002/hyp.7578, 2010.
Struthers, I. and Sivapalan, M.: A conceptual investigation of process controls upon flood frequency: role of thresholds, Hydrol. Earth Syst. Sci., 11, 1405–1416, https://doi.org/10.5194/hess-11-1405-2007, 2007.
Varado, N., Braud, I., Galle, S., Le Lay, M., Séguis, L., Kamagate, B., and Depraetere, C.: Multi-criteria assessment of the Representative Elementary Watershed approach on the Donga catchment (Benin) using a downward approach of model complexity, Hydrol. Earth Syst. Sci., 10, 427–442, https://doi.org/10.5194/hess-10-427-2006, 2006.
Viglione, A., Parajka, J., Rogger, M., Salinas, J. L., Laaha, G., Sivapalan, M., and Blöschl, G.: Comparative assessment of predictions in ungauged basins – Part 3: Runoff signatures in Austria, Hydrol. Earth Syst. Sci., 17, 2263-2279, https://doi.org/10.5194/hess-17-2263-2013, 2013.
Vrugt, J. A. and Sadegh, M.: Toward diagnostic model calibration and evaluation: Approximate Bayesian computation, Water Resour. Res., 49, 4335–4345, https://doi.org/10.1002/wrcr.20354, 2013.
Wagener, T., Sivapalan, M., Troch, P., and Woods, R.: Catchment Classification and Hydrologic Similarity, Geography Compass, 1, 901–931, https://doi.org/10.1111/j.1749-8198.2007.00039.x, 2007.
Wang, D. and Wu, L.: Similarity of climate control on base flow and perennial stream density in the Budyko framework, Hydrol. Earth Syst. Sci., 17, 315–324, https://doi.org/10.5194/hess-17-315-2013, 2013.
Wienhöfer, J., Germer, K., Lindenmaier, F., Färber, A., and Zehe, E.: Applied tracers for the observation of subsurface stormflow at the hillslope scale, Hydrol. Earth Syst. Sci., 13, 1145–1161, https://doi.org/10.5194/hess-13-1145-2009, 2009.
Wood, E. F., Sivapalan, M., and Beven, K.: Scale and similarity in catchment storm response, Rev. Geophys., 28, 1–18, 1990.
Woods, R.: The relative roles of climate, soil, vegetation and topography in determining seasonal and long-term catchment dynamics, Adv. Water Resour., 26, 295–309, https://doi.org/10.1016/S0309-1708(02)00164-1, 2003.
Wrede, S., Fenicia, F., Martinez-Carreras, N., Juilleret, J., Hissler, C., Krein, A., Savenije, H. H. G., Uhlenbrook, S., Kavetski, D., and Pfister, L.: Towards more systematic perceptual model development: A case study using 3 Luxembourgish catchments, Hydrol. Process., 29, 2731–2750, https://doi.org/10.1002/hyp.10393, 2015.
Ye, S., Yaeger, M., Coopersmith, E., Cheng, L., and Sivapalan, M.: Exploring the physical controls of regional patterns of flow duration curves – Part 2: Role of seasonality, the regime curve, and associated process controls, Hydrol. Earth Syst. Sci., 16, 4447–4465, https://doi.org/10.5194/hess-16-4447-2012, 2012.
Zehe, E. and Jackisch, C.: A Lagrangian model for soil water dynamics during rainfall-driven conditions, Hydrol. Earth Syst. Sci., 20, 3511–3526, https://doi.org/10.5194/hess-20-3511-2016, 2016.
Zehe, E., Maurer, T., Ihringer, J., and Plate, E.: Modeling water flow and mass transport in a loess catchment, Phys. Chem. Earth Pt. B, 26, 487–507, https://doi.org/10.1016/S1464-1909(01)00041-7, 2001.
Zehe, E., Ehret, U., Pfister, L., Blume, T., Schröder, B., Westhoff, M., Jackisch, C., Schymanski, S. J., Weiler, M., Schulz, K., Allroggen, N., Tronicke, J., van Schaik, L., Dietrich, P., Scherer, U., Eccard, J., Wulfmeyer, V., and Kleidon, A.: HESS Opinions: From response units to functional units: a thermodynamic reinterpretation of the HRU concept to link spatial organization and functioning of intermediate scale catchments, Hydrol. Earth Syst. Sci., 18, 4635–4655, https://doi.org/10.5194/hess-18-4635-2014, 2014.
Zhang, G. P., Savenije, H. H. G., Fenicia, F., and Pfister, L.: Modelling subsurface storm flow with the Representative Elementary Watershed (REW) approach: application to the Alzette River Basin, Hydrol. Earth Syst. Sci., 10, 937–955, https://doi.org/10.5194/hess-10-937-2006, 2006.
Short summary
Runoff production mechanisms and their corresponding physiographic controls continue to pose major research challenges in catchment hydrology. We propose innovative data-driven diagnostic signatures for overcoming the prevailing status quo in inter-comparison studies. Specifically, we present dimensionless double mass curves which allow us to infer information on runoff generation at the seasonal and annual timescales. The method is based on commonly available data.
Runoff production mechanisms and their corresponding physiographic controls continue to pose...
