Articles | Volume 23, issue 9
https://doi.org/10.5194/hess-23-3807-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/hess-23-3807-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
18 Sep 2019
Research article |
| 18 Sep 2019
| 18 Sep 2019
A topographic index explaining hydrological similarity by accounting for the joint controls of runoff formation
Institute for Water and River Basin Management, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
Axel Kleidon
Max-Planck-Institut für Biogeochemie, Jena, Germany
Conrad Jackisch
Institute for Water and River Basin Management, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
Institute of Geoecology, Department of Landscape Ecology and Environmental Systems Analysis, Technische Universität Braunschweig, Braunschweig, Germany
Martijn Westhoff
Faculty of Earth Science, Vrije Universiteit, Amsterdam, the Netherlands
Uwe Ehret
Institute for Water and River Basin Management, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
Hoshin Gupta
Department of Hydrology and Atmospheric
Sciences, The University of Arizona, Tucson, Arizona, USA
Erwin Zehe
Institute for Water and River Basin Management, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
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Downward longwave radiation (Rld) is critical for the surface energy budget, but its climatological variation on a global scale is not yet well understood physically. We use a semi-empirical equation derived by Brutsaert (1975) to identify the controlling role that atmospheric heat storage plays in spatiotemporal variations of Rld. Our work helps us to better understand aspects of climate variability, extreme events, and global warming by linking these to the mechanistic contributions of Rld.
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
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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.
Axel Kleidon
Earth Syst. Dynam., 14, 861–896, https://doi.org/10.5194/esd-14-861-2023, https://doi.org/10.5194/esd-14-861-2023, 2023
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The second law of thermodynamics has long intrigued scientists, but what role does it play in the Earth system? This review shows that its main role is that it shapes the conversion of sunlight into work. This work can then maintain the dynamics of the physical climate system, the biosphere, and human societies. The relevance of it is that apparently many processes work at their limits, directly or indirectly, so they become predictable by simple means.
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
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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
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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.
Luis Andres De la Fuente, Mohammad Reza Ehsani, Hoshin Vijai Gupta, and Laura E. Condon
EGUsphere, https://doi.org/10.5194/egusphere-2023-666, https://doi.org/10.5194/egusphere-2023-666, 2023
Preprint archived
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Long Short-Term Memory (LSTM) is a widely-used machine learning (ML) model in hydrology. However, it is difficult to extract knowledge from it. We propose HydroLSTM which represents processes analogous to a hydrological reservoir. Models using HydroLSTM perform similarly to LSTM but require fewer cell states. The learned parameters are informative about the dominant hydroclimatic characteristics of a catchment. Our results demonstrate how hydrological knowledge is encoded in the new structure.
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
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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.
Axel Kleidon, Gabriele Messori, Somnath Baidya Roy, Ira Didenkulova, and Ning Zeng
Earth Syst. Dynam., 14, 241–242, https://doi.org/10.5194/esd-14-241-2023, https://doi.org/10.5194/esd-14-241-2023, 2023
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
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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
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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.
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
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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.
Sarosh Alam Ghausi, Subimal Ghosh, and Axel Kleidon
Hydrol. Earth Syst. Sci., 26, 4431–4446, https://doi.org/10.5194/hess-26-4431-2022, https://doi.org/10.5194/hess-26-4431-2022, 2022
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The observed response of extreme precipitation to global warming remains unclear with significant regional variations. We show that a large part of this uncertainty can be removed when the imprint of clouds in surface temperatures is removed. We used a thermodynamic systems approach to remove the cloud radiative effect from temperatures. We then found that precipitation extremes intensified with global warming at positive rates which is consistent with physical arguments and model simulations.
Jonathan M. Frame, Frederik Kratzert, Daniel Klotz, Martin Gauch, Guy Shalev, Oren Gilon, Logan M. Qualls, Hoshin V. Gupta, and Grey S. Nearing
Hydrol. Earth Syst. Sci., 26, 3377–3392, https://doi.org/10.5194/hess-26-3377-2022, https://doi.org/10.5194/hess-26-3377-2022, 2022
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The most accurate rainfall–runoff predictions are currently based on deep learning. There is a concern among hydrologists that deep learning models may not be reliable in extrapolation or for predicting extreme events. This study tests that hypothesis. The deep learning models remained relatively accurate in predicting extreme events compared with traditional models, even when extreme events were not included in the training set.
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
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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
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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
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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
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
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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
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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
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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
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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
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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
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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
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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.
Axel Kleidon and Lee M. Miller
Geosci. Model Dev., 13, 4993–5005, https://doi.org/10.5194/gmd-13-4993-2020, https://doi.org/10.5194/gmd-13-4993-2020, 2020
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When winds are used as renewable energy by more and more wind turbines, one needs to account for the effect of wind turbines on the atmospheric flow. The Kinetic Energy Budget of the Atmosphere (KEBA) model provides a simple, physics-based approach to account for this effect very well when compared to much more detailed numerical simulations with an atmospheric model. KEBA should be useful to derive lower, more realistic wind energy resource potentials of different regions.
Annu Panwar, Maik Renner, and Axel Kleidon
Hydrol. Earth Syst. Sci., 24, 4923–4942, https://doi.org/10.5194/hess-24-4923-2020, https://doi.org/10.5194/hess-24-4923-2020, 2020
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Here we examine the effect of evaporative cooling across different vegetation types. Evaporation cools surface temperature significantly in short vegetation. In the forest, the high aerodynamic conductance explains 56 % of the reduced surface temperature. Therefore, the main cooling agent in the forest is the high aerodynamic conductance and not evaporation. Additionally, we propose the diurnal variation in surface temperature as being a potential indicator of evaporation in short vegetation.
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
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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
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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
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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
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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
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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.
Jianjun Zhang, Guangyao Gao, Bojie Fu, Cong Wang, Hoshin V. Gupta, Xiaoping Zhang, and Rui Li
Hydrol. Earth Syst. Sci., 24, 809–826, https://doi.org/10.5194/hess-24-809-2020, https://doi.org/10.5194/hess-24-809-2020, 2020
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We proposed an approach that integrates universal multifractals and a segmentation algorithm to precisely identify extreme precipitation (EP) and assess spatiotemporal EP variation over the Loess Plateau, using daily data. Our results explain how EP contributes to the widely distributed severe natural hazards. These findings are of great significance for ecological management in the Loess Plateau. Our approach is also helpful for spatiotemporal EP assessment at the regional scale.
Gabriela Chiquito Gesualdo, Paulo Tarso Oliveira, Dulce Buchala Bicca Rodrigues, and Hoshin Vijai Gupta
Hydrol. Earth Syst. Sci., 23, 4955–4968, https://doi.org/10.5194/hess-23-4955-2019, https://doi.org/10.5194/hess-23-4955-2019, 2019
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We investigate the influence of anticipated climate change on water security in the Jaguari Basin, which is the main source of freshwater for 9 million people in the São Paulo metropolitan region. Our findings indicate an expansion of the basin critical period, and identify October and November as the most vulnerable months. There is an urgent need to implement efficient mitigation and adaptation policies that recognize the annual pattern of variation between insecure and secure periods.
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
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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
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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.
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
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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.
Naoki Mizukami, Oldrich Rakovec, Andrew J. Newman, Martyn P. Clark, Andrew W. Wood, Hoshin V. Gupta, and Rohini Kumar
Hydrol. Earth Syst. Sci., 23, 2601–2614, https://doi.org/10.5194/hess-23-2601-2019, https://doi.org/10.5194/hess-23-2601-2019, 2019
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We find that Nash–Sutcliffe (NSE)-based model calibrations result in poor reproduction of high-flow events, such as the annual peak flows that are used for flood frequency estimation. The use of Kling–Gupta efficiency (KGE) results in annual peak flow estimates that are better than from NSE, with only a slight degradation in performance with respect to other related metrics.
Philipp Porada, Alexandra Tamm, Jose Raggio, Yafang Cheng, Axel Kleidon, Ulrich Pöschl, and Bettina Weber
Biogeosciences, 16, 2003–2031, https://doi.org/10.5194/bg-16-2003-2019, https://doi.org/10.5194/bg-16-2003-2019, 2019
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The trace gases NO and HONO are crucial for atmospheric chemistry. It has been suggested that biological soil crusts in drylands contribute substantially to global NO and HONO emissions, based on empirical upscaling of laboratory and field observations. Here we apply an alternative, process-based modeling approach to predict these emissions. We find that biological soil crusts emit globally significant amounts of NO and HONO, which also vary depending on the type of biological soil crust.
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
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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
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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.
Maik Renner, Claire Brenner, Kaniska Mallick, Hans-Dieter Wizemann, Luigi Conte, Ivonne Trebs, Jianhui Wei, Volker Wulfmeyer, Karsten Schulz, and Axel Kleidon
Hydrol. Earth Syst. Sci., 23, 515–535, https://doi.org/10.5194/hess-23-515-2019, https://doi.org/10.5194/hess-23-515-2019, 2019
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We estimate the phase lag of surface states and heat fluxes to incoming solar radiation at the sub-daily timescale. While evapotranspiration reveals a minor phase lag, the vapor pressure deficit used as input by Penman–Monteith approaches shows a large phase lag. The surface-to-air temperature gradient used by energy balance residual approaches shows a small phase shift in agreement with the sensible heat flux and thus explains the better correlation of these models at the sub-daily timescale.
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
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
Axel Kleidon and Maik Renner
Earth Syst. Dynam., 9, 1127–1140, https://doi.org/10.5194/esd-9-1127-2018, https://doi.org/10.5194/esd-9-1127-2018, 2018
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Turbulent fluxes represent an efficient way to transport heat and moisture from the surface into the atmosphere. Due to their inherently highly complex nature, they are commonly described by semiempirical relationships. What we show here is that these fluxes can also be predicted by viewing them as the outcome of a heat engine that operates between the warm surface and the cooler atmosphere and that works at its limit.
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
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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
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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
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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.
Corina Buendía, Axel Kleidon, Stefano Manzoni, Björn Reu, and Amilcare Porporato
Biogeosciences, 15, 279–295, https://doi.org/10.5194/bg-15-279-2018, https://doi.org/10.5194/bg-15-279-2018, 2018
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Amazonia is highly biodiverse and of global importance for regulating the climate system. Because soils are highly weathered, phosphorus (P) is suggested to limit ecosystem productivity. Here, we evaluate the importance of P redistribution by animals using a simple mathematical model synthesizing the major processes of the Amazon P cycle. Our findings suggest that food web complexity plays an important role for sustaining the productivity of terra firme forests.
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
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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.
Axel Kleidon and Hubert H. G. Savenije
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2017-674, https://doi.org/10.5194/hess-2017-674, 2017
Revised manuscript not accepted
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At larger scales, the flow of rivers can often be described by a relatively simple, exponential decay, and it is unclear how such simple behaviour can be explained given that river basins show such vast complexity. Here, we use a highly idealised model to show that such simple behaviour can be explained by viewing it as the emergent consequence of the groundwater system (which feeds river flow) minimising its energy dissipation.
Axel Kleidon and Maik Renner
Earth Syst. Dynam., 8, 849–864, https://doi.org/10.5194/esd-8-849-2017, https://doi.org/10.5194/esd-8-849-2017, 2017
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We provide an explanation why land temperatures respond more strongly to global warming than ocean temperatures, a robust finding in observations and models that has so far not been understood well. We explain it by the different ways by which ocean and land surfaces buffer the strong variation in solar radiation and demonstrate this with a simple, physically based model. Our explanation also illustrates why nighttime temperatures warm more strongly, another robust finding of global warming.
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
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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
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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.
Simon Paul Seibert, Conrad Jackisch, Uwe Ehret, Laurent Pfister, and Erwin Zehe
Hydrol. Earth Syst. Sci., 21, 2817–2841, https://doi.org/10.5194/hess-21-2817-2017, https://doi.org/10.5194/hess-21-2817-2017, 2017
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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.
Philipp Porada, Ulrich Pöschl, Axel Kleidon, Christian Beer, and Bettina Weber
Biogeosciences, 14, 1593–1602, https://doi.org/10.5194/bg-14-1593-2017, https://doi.org/10.5194/bg-14-1593-2017, 2017
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Lichens and bryophytes have been shown to release nitrous oxide, which is a strong greenhouse gas and atmospheric ozone-depleting agent. Here we apply a process-based computer model of lichens and bryophytes at the global scale, to estimate growth and respiration of the organisms. By relating respiration to nitrous oxide release, we simulate global nitrous oxide emissions of 0.27 (0.19–0.35) Tg yr−1. Moreover, we quantify different sources of uncertainty in nitrous oxide emission rates.
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
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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.
Tirthankar Roy, Hoshin V. Gupta, Aleix Serrat-Capdevila, and Juan B. Valdes
Hydrol. Earth Syst. Sci., 21, 879–896, https://doi.org/10.5194/hess-21-879-2017, https://doi.org/10.5194/hess-21-879-2017, 2017
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This study presents and compares two different approaches to using satellite-derived estimates of actual evapotranspiration (ET) to improve the performance of a conceptual rainfall–runoff model. In the first approach, the ET process within the model is constrained using the satellite ET estimates, while in the second one, the model structure is altered. Results indicate that both the approaches improve streamflow forecasting, while the second one also improves the ET simulations significantly.
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
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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
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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
Anke Hildebrandt, Axel Kleidon, and Marcel Bechmann
Hydrol. Earth Syst. Sci., 20, 3441–3454, https://doi.org/10.5194/hess-20-3441-2016, https://doi.org/10.5194/hess-20-3441-2016, 2016
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This theoretical paper describes the energy fluxes and dissipation along the flow paths involved in root water uptake, an approach that is rarely taken. We show that this provides useful additional insights for understanding the biotic and abiotic impediments to root water uptake. This approach shall be applied to explore efficient water uptake strategies and help locate the limiting processes in the complex soil–plant–atmosphere system.
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
Maik Renner, Sibylle K. Hassler, Theresa Blume, Markus Weiler, Anke Hildebrandt, Marcus Guderle, Stanislaus J. Schymanski, and Axel Kleidon
Hydrol. Earth Syst. Sci., 20, 2063–2083, https://doi.org/10.5194/hess-20-2063-2016, https://doi.org/10.5194/hess-20-2063-2016, 2016
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We estimated forest transpiration (European beech) along a steep valley cross section. Atmospheric demand, obtained by the thermodynamic limit of maximum power, is the dominant control of transpiration at all sites.
To our surprise we find that transpiration is rather similar across sites with different aspect (north vs. south) and different stand structure due to systematically varying sap velocities. Such a compensation effect is highly relevant for modeling and upscaling of transpiration.
Hernan A. Moreno, Hoshin V. Gupta, Dave D. White, and David A. Sampson
Hydrol. Earth Syst. Sci., 20, 1241–1267, https://doi.org/10.5194/hess-20-1241-2016, https://doi.org/10.5194/hess-20-1241-2016, 2016
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We use a distributed hydrologic model to document the potential impacts of a forest restoration project on the mean and extreme hydrologic conditions on a water-supply, semi-arid basin. Results show shifts in spatio-temporal patterns of interception, soil moisture, evapotranspiration, snow persistence and runoff production differently in contrasting aspect slopes. Forest thinning leads to net loss of surface water storage and to a less regulated runoff response during hydrologic extremes.
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
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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.
Z. H. He, F. Q. Tian, H. V. Gupta, H. C. Hu, and H. P. Hu
Hydrol. Earth Syst. Sci., 19, 1807–1826, https://doi.org/10.5194/hess-19-1807-2015, https://doi.org/10.5194/hess-19-1807-2015, 2015
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
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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.
S. Gharari, M. Shafiei, M. Hrachowitz, R. Kumar, F. Fenicia, H. V. Gupta, and H. H. G. Savenije
Hydrol. Earth Syst. Sci., 18, 4861–4870, https://doi.org/10.5194/hess-18-4861-2014, https://doi.org/10.5194/hess-18-4861-2014, 2014
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
C. Buendía, S. Arens, T. Hickler, S. I. Higgins, P. Porada, and A. Kleidon
Biogeosciences, 11, 3661–3683, https://doi.org/10.5194/bg-11-3661-2014, https://doi.org/10.5194/bg-11-3661-2014, 2014
A. Kleidon, M. Renner, and P. Porada
Hydrol. Earth Syst. Sci., 18, 2201–2218, https://doi.org/10.5194/hess-18-2201-2014, https://doi.org/10.5194/hess-18-2201-2014, 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
H. V. Gupta, C. Perrin, G. Blöschl, A. Montanari, R. Kumar, M. Clark, and V. Andréassian
Hydrol. Earth Syst. Sci., 18, 463–477, https://doi.org/10.5194/hess-18-463-2014, https://doi.org/10.5194/hess-18-463-2014, 2014
S. P. K. Bowring, L. M. Miller, L. Ganzeveld, and A. Kleidon
Earth Syst. Dynam., 5, 43–53, https://doi.org/10.5194/esd-5-43-2014, https://doi.org/10.5194/esd-5-43-2014, 2014
Z. He, F. Tian, H. C. Hu, H. V. Gupta, and H. P. Hu
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hessd-11-1253-2014, https://doi.org/10.5194/hessd-11-1253-2014, 2014
Revised manuscript not accepted
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
A. Kleidon and M. Renner
Earth Syst. Dynam., 4, 455–465, https://doi.org/10.5194/esd-4-455-2013, https://doi.org/10.5194/esd-4-455-2013, 2013
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
P. Porada, B. Weber, W. Elbert, U. Pöschl, and A. Kleidon
Biogeosciences, 10, 6989–7033, https://doi.org/10.5194/bg-10-6989-2013, https://doi.org/10.5194/bg-10-6989-2013, 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
E. Simoncini, N. Virgo, and A. Kleidon
Earth Syst. Dynam., 4, 317–331, https://doi.org/10.5194/esd-4-317-2013, https://doi.org/10.5194/esd-4-317-2013, 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. Kleidon and M. Renner
Hydrol. Earth Syst. Sci., 17, 2873–2892, https://doi.org/10.5194/hess-17-2873-2013, https://doi.org/10.5194/hess-17-2873-2013, 2013
V. López-Burgos, H. V. Gupta, and M. Clark
Hydrol. Earth Syst. Sci., 17, 1809–1823, https://doi.org/10.5194/hess-17-1809-2013, https://doi.org/10.5194/hess-17-1809-2013, 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
Delayed stormflow generation in a semi-humid forested watershed controlled by soil water storage and groundwater dynamics
HESS Opinions: Floods and droughts – are land use, soil management, and landscape hydrology more significant drivers than increasing CO2?
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
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
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
Zhen Cui and Fuqiang Tian
Hydrol. Earth Syst. Sci., 29, 2275–2291, https://doi.org/10.5194/hess-29-2275-2025, https://doi.org/10.5194/hess-29-2275-2025, 2025
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This study investigates stormflow patterns in a forested watershed in north China, highlighting the fact that delayed stormflow is governed by soil water content (SWC) and groundwater level (GWL). When SWC exceeds its storage capacity, excess water infiltrates, recharging groundwater and gradually elevating GWL. Rising GWL enhances subsurface connectivity and lateral flow, synchronizing watershed responses and, in extreme cases, causing a delayed stormflow peak to merge with the direct stormflow peak.
Karl Auerswald, Juergen Geist, John N. Quinton, and Peter Fiener
Hydrol. Earth Syst. Sci., 29, 2185–2200, https://doi.org/10.5194/hess-29-2185-2025, https://doi.org/10.5194/hess-29-2185-2025, 2025
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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, is likely to be more significant for water losses by runoff leading to flooding and water scarcity and is therefore an important part of the solution to mitigate floods, droughts, and heatwaves.
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
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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
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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
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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
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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
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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
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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
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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.
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
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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
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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
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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
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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.
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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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.
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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.
In this study, we develop a topographic index explaining hydrological similarity within a...
