Articles | Volume 29, issue 15
https://doi.org/10.5194/hess-29-3727-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/hess-29-3727-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
14 Aug 2025
Research article |
| 14 Aug 2025
| 14 Aug 2025
Unsupervised image velocimetry for automated computation of river flow velocities
Matthew T. Perks
CORRESPONDING AUTHOR
School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, United Kingdom
Borbála Hortobágyi
School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, United Kingdom
UMR5600 EVS, CNRS, ENS Lyon, Lyon, France
Nick Everard
UK Centre for Ecology and Hydrology, Wallingford, United Kingdom
Susan Manson
Flood and Coastal Risk Management, Environment Agency, Crosskill House, Mill Lane, Beverley, United Kingdom
Juliet Rowland
Environment Agency, Manley House, Kestrel Way, Exeter, UK
Andrew Large
School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, United Kingdom
Andrew J. Russell
School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, United Kingdom
Related authors
Robert Ljubičić, Dariia Strelnikova, Matthew T. Perks, Anette Eltner, Salvador Peña-Haro, Alonso Pizarro, Silvano Fortunato Dal Sasso, Ulf Scherling, Pietro Vuono, and Salvatore Manfreda
Hydrol. Earth Syst. Sci., 25, 5105–5132, https://doi.org/10.5194/hess-25-5105-2021, https://doi.org/10.5194/hess-25-5105-2021, 2021
Short summary
Short summary
The rise of new technologies such as drones (unmanned aerial systems – UASs) has allowed widespread use of image velocimetry techniques in place of more traditional, usually slower, methods during hydrometric campaigns. In order to minimize the velocity estimation errors, one must stabilise the acquired videos. In this research, we compare the performance of different UAS video stabilisation tools and provide guidelines for their use in videos with different flight and ground conditions.
Matthew T. Perks
Geosci. Model Dev., 13, 6111–6130, https://doi.org/10.5194/gmd-13-6111-2020, https://doi.org/10.5194/gmd-13-6111-2020, 2020
Short summary
Short summary
KLT-IV v1.0 offers a user-friendly graphical interface for the determination of river flow velocity and river discharge using videos acquired from both fixed and mobile remote sensing platforms. Platform motion can be accounted for using ground control points and/or stable features or a GPS device and inertial measurement unit sensor. Examples of the KLT-IV workflow are provided for two case studies where footage is acquired using unmanned aerial systems and fixed cameras.
Alonso Pizarro, Silvano F. Dal Sasso, Matthew T. Perks, and Salvatore Manfreda
Hydrol. Earth Syst. Sci., 24, 5173–5185, https://doi.org/10.5194/hess-24-5173-2020, https://doi.org/10.5194/hess-24-5173-2020, 2020
Short summary
Short summary
An innovative approach is presented to optimise image-velocimetry performances for surface flow velocity estimates (and thus remotely sensed river discharges). Synthetic images were generated under different tracer characteristics using a numerical approach. Based on the results, the Seeding Distribution Index was introduced as a descriptor of the optimal portion of the video to analyse. A field case study was considered as a proof of concept of the proposed framework showing error reductions.
Matthew T. Perks, Silvano Fortunato Dal Sasso, Alexandre Hauet, Elizabeth Jamieson, Jérôme Le Coz, Sophie Pearce, Salvador Peña-Haro, Alonso Pizarro, Dariia Strelnikova, Flavia Tauro, James Bomhof, Salvatore Grimaldi, Alain Goulet, Borbála Hortobágyi, Magali Jodeau, Sabine Käfer, Robert Ljubičić, Ian Maddock, Peter Mayr, Gernot Paulus, Lionel Pénard, Leigh Sinclair, and Salvatore Manfreda
Earth Syst. Sci. Data, 12, 1545–1559, https://doi.org/10.5194/essd-12-1545-2020, https://doi.org/10.5194/essd-12-1545-2020, 2020
Short summary
Short summary
We present datasets acquired from seven countries across Europe and North America consisting of image sequences. These have been subjected to a range of pre-processing methods in preparation for image velocimetry analysis. These datasets and accompanying reference data are a resource that may be used for conducting benchmarking experiments, assessing algorithm performances, and focusing future software development.
Matthew T. Perks, Andrew J. Russell, and Andrew R. G. Large
Hydrol. Earth Syst. Sci., 20, 4005–4015, https://doi.org/10.5194/hess-20-4005-2016, https://doi.org/10.5194/hess-20-4005-2016, 2016
Short summary
Short summary
Unmanned aerial vehicles (UAVs) have the potential to capture information about the earth’s surface in dangerous and previously inaccessible locations. Here we present a method whereby image acquisition and subsequent analysis have enabled the highly dynamic and oft-immeasurable hydraulic phenomenon present during high-energy flash floods to be quantified at previously unattainable spatial and temporal resolutions.
Matthew Thomas Perks and Jeff Warburton
Earth Surf. Dynam., 4, 705–719, https://doi.org/10.5194/esurf-4-705-2016, https://doi.org/10.5194/esurf-4-705-2016, 2016
Short summary
Short summary
We appraise the success of a novel mitigation approach and subsequent adaptive management, designed to reduce the transfer of fine sediment in a small upland catchment in the UK. Analysis of the river response demonstrates that the fluvial sediment system has become more restrictive with reduced fine sediment transfer. The study demonstrates that channel reconfiguration can be effective in mitigating fine sediment flux in upland streams but the full value of this may take many years to achieve.
Robert Ljubičić, Dariia Strelnikova, Matthew T. Perks, Anette Eltner, Salvador Peña-Haro, Alonso Pizarro, Silvano Fortunato Dal Sasso, Ulf Scherling, Pietro Vuono, and Salvatore Manfreda
Hydrol. Earth Syst. Sci., 25, 5105–5132, https://doi.org/10.5194/hess-25-5105-2021, https://doi.org/10.5194/hess-25-5105-2021, 2021
Short summary
Short summary
The rise of new technologies such as drones (unmanned aerial systems – UASs) has allowed widespread use of image velocimetry techniques in place of more traditional, usually slower, methods during hydrometric campaigns. In order to minimize the velocity estimation errors, one must stabilise the acquired videos. In this research, we compare the performance of different UAS video stabilisation tools and provide guidelines for their use in videos with different flight and ground conditions.
Chloe Leach, Tom Coulthard, Andrew Barkwith, Daniel R. Parsons, and Susan Manson
Geosci. Model Dev., 14, 5507–5523, https://doi.org/10.5194/gmd-14-5507-2021, https://doi.org/10.5194/gmd-14-5507-2021, 2021
Short summary
Short summary
Numerical models can be used to understand how coastal systems evolve over time, including likely responses to climate change. However, many existing models are aimed at simulating 10- to 100-year time periods do not represent a vertical dimension and are thus unable to include the effect of sea-level rise. The Coastline Evolution Model 2D (CEM2D) presented in this paper is an advance in this field, with the inclusion of the vertical coastal profile against which the water level can be altered.
Matthew T. Perks
Geosci. Model Dev., 13, 6111–6130, https://doi.org/10.5194/gmd-13-6111-2020, https://doi.org/10.5194/gmd-13-6111-2020, 2020
Short summary
Short summary
KLT-IV v1.0 offers a user-friendly graphical interface for the determination of river flow velocity and river discharge using videos acquired from both fixed and mobile remote sensing platforms. Platform motion can be accounted for using ground control points and/or stable features or a GPS device and inertial measurement unit sensor. Examples of the KLT-IV workflow are provided for two case studies where footage is acquired using unmanned aerial systems and fixed cameras.
Alonso Pizarro, Silvano F. Dal Sasso, Matthew T. Perks, and Salvatore Manfreda
Hydrol. Earth Syst. Sci., 24, 5173–5185, https://doi.org/10.5194/hess-24-5173-2020, https://doi.org/10.5194/hess-24-5173-2020, 2020
Short summary
Short summary
An innovative approach is presented to optimise image-velocimetry performances for surface flow velocity estimates (and thus remotely sensed river discharges). Synthetic images were generated under different tracer characteristics using a numerical approach. Based on the results, the Seeding Distribution Index was introduced as a descriptor of the optimal portion of the video to analyse. A field case study was considered as a proof of concept of the proposed framework showing error reductions.
Louise Arnal, Liz Anspoks, Susan Manson, Jessica Neumann, Tim Norton, Elisabeth Stephens, Louise Wolfenden, and Hannah Louise Cloke
Geosci. Commun., 3, 203–232, https://doi.org/10.5194/gc-3-203-2020, https://doi.org/10.5194/gc-3-203-2020, 2020
Short summary
Short summary
The Environment Agency (EA), responsible for flood risk management in England, is moving towards the use of probabilistic river flood forecasts. By showing the likelihood of future floods, they can allow earlier anticipation. But making decisions on probabilistic information is complex and interviews with EA decision-makers highlight the practical challenges and opportunities of this transition. We make recommendations to support a successful transition for flood early warning in England.
Matthew T. Perks, Silvano Fortunato Dal Sasso, Alexandre Hauet, Elizabeth Jamieson, Jérôme Le Coz, Sophie Pearce, Salvador Peña-Haro, Alonso Pizarro, Dariia Strelnikova, Flavia Tauro, James Bomhof, Salvatore Grimaldi, Alain Goulet, Borbála Hortobágyi, Magali Jodeau, Sabine Käfer, Robert Ljubičić, Ian Maddock, Peter Mayr, Gernot Paulus, Lionel Pénard, Leigh Sinclair, and Salvatore Manfreda
Earth Syst. Sci. Data, 12, 1545–1559, https://doi.org/10.5194/essd-12-1545-2020, https://doi.org/10.5194/essd-12-1545-2020, 2020
Short summary
Short summary
We present datasets acquired from seven countries across Europe and North America consisting of image sequences. These have been subjected to a range of pre-processing methods in preparation for image velocimetry analysis. These datasets and accompanying reference data are a resource that may be used for conducting benchmarking experiments, assessing algorithm performances, and focusing future software development.
Matthew T. Perks, Andrew J. Russell, and Andrew R. G. Large
Hydrol. Earth Syst. Sci., 20, 4005–4015, https://doi.org/10.5194/hess-20-4005-2016, https://doi.org/10.5194/hess-20-4005-2016, 2016
Short summary
Short summary
Unmanned aerial vehicles (UAVs) have the potential to capture information about the earth’s surface in dangerous and previously inaccessible locations. Here we present a method whereby image acquisition and subsequent analysis have enabled the highly dynamic and oft-immeasurable hydraulic phenomenon present during high-energy flash floods to be quantified at previously unattainable spatial and temporal resolutions.
Matthew Thomas Perks and Jeff Warburton
Earth Surf. Dynam., 4, 705–719, https://doi.org/10.5194/esurf-4-705-2016, https://doi.org/10.5194/esurf-4-705-2016, 2016
Short summary
Short summary
We appraise the success of a novel mitigation approach and subsequent adaptive management, designed to reduce the transfer of fine sediment in a small upland catchment in the UK. Analysis of the river response demonstrates that the fluvial sediment system has become more restrictive with reduced fine sediment transfer. The study demonstrates that channel reconfiguration can be effective in mitigating fine sediment flux in upland streams but the full value of this may take many years to achieve.
Related subject area
Subject: Rivers and Lakes | Techniques and Approaches: Instruments and observation techniques
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Hydrological, meteorological, and watershed controls on the water balance of thermokarst lakes between Inuvik and Tuktoyaktuk, Northwest Territories, Canada
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Assessing the influence of lake and watershed attributes on snowmelt bypass at thermokarst lakes
Technical note: Analyzing river network dynamics and the active length–discharge relationship using water presence sensors
Technical note: Efficient imaging of hydrological units below lakes and fjords with a floating, transient electromagnetic (FloaTEM) system
Drastic decline of flood pulse in the Cambodian floodplains (Mekong River and Tonle Sap system)
Seasonality of density currents induced by differential cooling
Implications of variations in stream specific conductivity for estimating baseflow using chemical mass balance and calibrated hydrograph techniques
Enhanced flood hazard assessment beyond decadal climate cycles based on centennial historical data (Duero basin, Spain)
Contrasting hydrological and thermal intensities determine seasonal lake-level variations – a case study at Paiku Co on the southern Tibetan Plateau
Technical note: Mobile open dynamic chamber measurement of methane macroseeps in lakes
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Technical note: Greenhouse gas flux studies: an automated online system for gas emission measurements in aquatic environments
Evolution and dynamics of the vertical temperature profile in an oligotrophic lake
Long-term changes in central European river discharge for 1869–2016: impact of changing snow covers, reservoir constructions and an intensified hydrological cycle
Reliable reference for the methane concentrations in Lake Kivu at the beginning of industrial exploitation
Small dams alter thermal regimes of downstream water
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Turbulent mixing and heat fluxes under lake ice: the role of seiche oscillations
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Long-term temporal trajectories to enhance restoration efficiency and sustainability on large rivers: an interdisciplinary study
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Effectiveness of distributed temperature measurements for early detection of piping in river embankments
Citizen observations contributing to flood modelling: opportunities and challenges
Dead Sea evaporation by eddy covariance measurements vs. aerodynamic, energy budget, Priestley–Taylor, and Penman estimates
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Application of CryoSat-2 altimetry data for river analysis and modelling
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Using radon to understand parafluvial flows and the changing locations of groundwater inflows in the Avon River, southeast Australia
Influence of environmental factors on spectral characteristics of chromophoric dissolved organic matter (CDOM) in Inner Mongolia Plateau, China
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The Global Network of Isotopes in Rivers (GNIR): integration of water isotopes in watershed observation and riverine research
A 2600-year history of floods in the Bernese Alps, Switzerland: frequencies, mechanisms and climate forcing
Technical Note: Semi-automated effective width extraction from time-lapse RGB imagery of a remote, braided Greenlandic river
Characterization of sediment layer composition in a shallow lake: from open water zones to reed belt areas
Morphological, hydrological, biogeochemical and ecological changes and challenges in river restoration – the Thur River case study
Dynamics of auto- and heterotrophic picoplankton and associated viruses in Lake Geneva
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Hydrochemical variability at the Upper Paraguay Basin and Pantanal wetland
Georgiy B. Kirillin, Tom Shatwell, and Alexander S. Izhitskiy
Hydrol. Earth Syst. Sci., 29, 3569–3588, https://doi.org/10.5194/hess-29-3569-2025, https://doi.org/10.5194/hess-29-3569-2025, 2025
Short summary
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The Aral Sea is both an example of large-scale environmental degradation caused by human activity and a message of hope through its partial restoration. Our study shows that the restored part of the Aral Sea is now healthy in terms of vertical mixing and oxygenation. However, small perturbations of water level or transparency could significantly alter the entire ecosystem. The results contribute to understanding the consequences of large-scale lake management worldwide.
Mauro Lourenco, Rutledge S. Boyes, Fenton P. D. Cotterill, Tyrel Flügel, Frank C. Nyoni, Goabaone J. Ramatlapeng, and Rainer von Brandis
EGUsphere, https://doi.org/10.5194/egusphere-2025-837, https://doi.org/10.5194/egusphere-2025-837, 2025
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This study focused on the sources of the Zambezi River, revealing new insights into its longest tributary and Angola’s key role in its flow. River expeditions and earth observation data show that Angola contributes over 70 % of the river's flow upstream of a major floodplain. We highlight Angola’s wetlands, which support river health and help mitigate pollution. These findings stress the need for improved monitoring and regional cooperation to protect the Zambezi River Basin and its ecosystems.
Domenico Miglino, Khim Cathleen Saddi, Francesco Isgrò, Seifeddine Jomaa, Michael Rode, and Salvatore Manfreda
EGUsphere, https://doi.org/10.5194/egusphere-2024-2172, https://doi.org/10.5194/egusphere-2024-2172, 2024
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Turbidity is a key factor for water quality monitoring. We tested an image-based procedure in a full-scale river monitoring experiment using digital cameras. This procedure can increase our knowledge of the real status of water bodies, solving the spatial and temporal data resolution problems of the existing techniques, promoting also the development of early warning networks, moving water research forward thanks to a large increase of information and the reduction of operating expenses.
Evan J. Wilcox, Brent B. Wolfe, and Philip Marsh
Hydrol. Earth Syst. Sci., 27, 2173–2188, https://doi.org/10.5194/hess-27-2173-2023, https://doi.org/10.5194/hess-27-2173-2023, 2023
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The Arctic is warming quickly and influencing lake water balances. We used water isotope concentrations taken from samples of 25 lakes in the Canadian Arctic and estimated the average ratio of evaporation to inflow (E / I) for each lake. The ratio of watershed area (the area that flows into the lake) to lake area (WA / LA) strongly predicted E / I, as lakes with relatively smaller watersheds received less inflow. The WA / LA could be used to predict the vulnerability of Arctic lakes to future change.
Monika Barbara Kalinowska, Kaisa Västilä, Michael Nones, Adam Kiczko, Emilia Karamuz, Andrzej Brandyk, Adam Kozioł, and Marcin Krukowski
Hydrol. Earth Syst. Sci., 27, 953–968, https://doi.org/10.5194/hess-27-953-2023, https://doi.org/10.5194/hess-27-953-2023, 2023
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Vegetation is commonly found in rivers and channels. Using field investigations, we evaluated the influence of different vegetation coverages on the flow and mixing in the small naturally vegetated channel. The obtained results are expected to be helpful for practitioners, enlarge our still limited knowledge, and show the further required scientific directions for a better understanding of the influence of vegetation on the flow and mixing of dissolved substances in real natural conditions.
Evan J. Wilcox, Brent B. Wolfe, and Philip Marsh
Hydrol. Earth Syst. Sci., 26, 6185–6205, https://doi.org/10.5194/hess-26-6185-2022, https://doi.org/10.5194/hess-26-6185-2022, 2022
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We estimated how much of the water flowing into lakes during snowmelt replaced the pre-snowmelt lake water. Our data show that, as lake depth increases, the amount of water mixed into lakes decreased, because vertical mixing is reduced as lake depth increases. Our data also show that the water mixing into lakes is not solely snow-sourced but is a mixture of snowmelt and soil water. These results are relevant for lake biogeochemistry given the unique properties of snowmelt runoff.
Francesca Zanetti, Nicola Durighetto, Filippo Vingiani, and Gianluca Botter
Hydrol. Earth Syst. Sci., 26, 3497–3516, https://doi.org/10.5194/hess-26-3497-2022, https://doi.org/10.5194/hess-26-3497-2022, 2022
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River networks are highly dynamical. Characterizing expansion and retraction of flowing streams is a significant scientific challenge. Electrical resistance sensors were used to monitor stream network patterns in an alpine catchment. Our data show the presence of spatial heterogeneity in network dynamics and that the active length is more sensitive than discharge to small rain events. The study unravels potentials and limitations of the sensors for the characterization of temporary streams.
Pradip Kumar Maurya, Frederik Ersted Christensen, Masson Andy Kass, Jesper B. Pedersen, Rasmus R. Frederiksen, Nikolaj Foged, Anders Vest Christiansen, and Esben Auken
Hydrol. Earth Syst. Sci., 26, 2813–2827, https://doi.org/10.5194/hess-26-2813-2022, https://doi.org/10.5194/hess-26-2813-2022, 2022
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In this paper, we present an application of the electromagnetic method to image the subsurface below rivers, lakes, or any surface water body. The scanning of the subsurface is carried out by sailing an electromagnetic sensor called FloaTEM. Imaging results show a 3D distribution of different sediment types below the freshwater lakes. In the case of saline water, the system is capable of identifying the probable location of groundwater discharge into seawater.
Samuel De Xun Chua, Xi Xi Lu, Chantha Oeurng, Ty Sok, and Carl Grundy-Warr
Hydrol. Earth Syst. Sci., 26, 609–625, https://doi.org/10.5194/hess-26-609-2022, https://doi.org/10.5194/hess-26-609-2022, 2022
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We found that the annual flood at the Cambodian floodplains decreased from 1960 to 2019. Consequently, the Tonle Sap Lake, the largest lake in Southeast Asia, is shrinking. The results are worrying because the local fisheries and planting calendar might be disrupted. This drastic decline of flooding extent is caused mostly by local factors, namely water withdrawal for irrigation and channel incision from sand mining activities.
Tomy Doda, Cintia L. Ramón, Hugo N. Ulloa, Alfred Wüest, and Damien Bouffard
Hydrol. Earth Syst. Sci., 26, 331–353, https://doi.org/10.5194/hess-26-331-2022, https://doi.org/10.5194/hess-26-331-2022, 2022
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At night or during cold periods, the shallow littoral region of lakes cools faster than their deeper interior. This induces a cold downslope current that carries littoral waters offshore. From a 1-year-long database collected in a small temperate lake, we resolve the seasonality of this current and report its frequent occurrence from summer to winter. This study contributes to a better quantification of lateral exchange in lakes, with implications for the transport of dissolved compounds.
Ian Cartwright
Hydrol. Earth Syst. Sci., 26, 183–195, https://doi.org/10.5194/hess-26-183-2022, https://doi.org/10.5194/hess-26-183-2022, 2022
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Using specific conductivity (SC) to estimate groundwater inflow to rivers is complicated by bank return waters, interflow, and flows off floodplains contributing to baseflow in all but the driest years. Using the maximum SC of the river in dry years to estimate the SC of groundwater produces the best baseflow vs. streamflow trends. The variable composition of baseflow hinders calibration of hydrograph-based techniques to estimate groundwater inflows.
Gerardo Benito, Olegario Castillo, Juan A. Ballesteros-Cánovas, Maria Machado, and Mariano Barriendos
Hydrol. Earth Syst. Sci., 25, 6107–6132, https://doi.org/10.5194/hess-25-6107-2021, https://doi.org/10.5194/hess-25-6107-2021, 2021
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Climate change is expected to increase the intensity of floods, but changes are difficult to project. We compiled historical and modern flood data of the Rio Duero (Spain) to evaluate flood hazards beyond decadal climate cycles. Historical floods were obtained from documentary sources, identifying 69 floods over 1250–1871 CE. Discharges were calculated from reported flood heights. Flood frequency using historical datasets showed the most robust results, guiding climate change adaptation.
Yanbin Lei, Tandong Yao, Kun Yang, Lazhu, Yaoming Ma, and Broxton W. Bird
Hydrol. Earth Syst. Sci., 25, 3163–3177, https://doi.org/10.5194/hess-25-3163-2021, https://doi.org/10.5194/hess-25-3163-2021, 2021
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Lake evaporation from Paiku Co on the TP is low in spring and summer and high in autumn and early winter. There is a ~ 5-month lag between net radiation and evaporation due to large lake heat storage. High evaporation and low inflow cause significant lake-level decrease in autumn and early winter, while low evaporation and high inflow cause considerable lake-level increase in summer. This study implies that evaporation can affect the different amplitudes of lake-level variations on the TP.
Frederic Thalasso, Katey Walter Anthony, Olya Irzak, Ethan Chaleff, Laughlin Barker, Peter Anthony, Philip Hanke, and Rodrigo Gonzalez-Valencia
Hydrol. Earth Syst. Sci., 24, 6047–6058, https://doi.org/10.5194/hess-24-6047-2020, https://doi.org/10.5194/hess-24-6047-2020, 2020
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Methane (CH4) seepage is the steady or episodic flow of gaseous hydrocarbons from subsurface reservoirs that has been identified as a significant source of atmospheric CH4. The monitoring of these emissions is important and despite several available methods, large macroseeps are still difficult to measure due to a lack of a lightweight and inexpensive method deployable in remote environments. Here, we report the development of a mobile chamber for measuring intense CH4 macroseepage in lakes.
Shangbin Xiao, Liu Liu, Wei Wang, Andreas Lorke, Jason Woodhouse, and Hans-Peter Grossart
Hydrol. Earth Syst. Sci., 24, 3871–3880, https://doi.org/10.5194/hess-24-3871-2020, https://doi.org/10.5194/hess-24-3871-2020, 2020
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To better understand the fate of methane (CH4) and carbon dioxide (CO2) in freshwaters, dissolved CH4 and CO2 need to be measured with a high temporal resolution. We developed the Fast-Response Automated Gas Equilibrator (FaRAGE) for real-time in situ measurement of dissolved gases in water. FaRAGE can achieve a short response time (CH4:
t95 % = 12 s; CO2:
t95 % = 10 s) while retaining a high equilibration ratio and accuracy.
Nguyen Thanh Duc, Samuel Silverstein, Martin Wik, Patrick Crill, David Bastviken, and Ruth K. Varner
Hydrol. Earth Syst. Sci., 24, 3417–3430, https://doi.org/10.5194/hess-24-3417-2020, https://doi.org/10.5194/hess-24-3417-2020, 2020
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Under rapid ongoing climate change, accurate quantification of natural greenhouse gas emissions in aquatic environments such as lakes and ponds is needed to understand regulation and feedbacks. Building on the rapid development in wireless communication, sensors, and computation technology, we present a low-cost, open-source, automated and remotely accessed and controlled device for carbon dioxide and methane fluxes from open-water environments along with tests showing their potential.
Zvjezdana B. Klaić, Karmen Babić, and Mirko Orlić
Hydrol. Earth Syst. Sci., 24, 3399–3416, https://doi.org/10.5194/hess-24-3399-2020, https://doi.org/10.5194/hess-24-3399-2020, 2020
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Fine-resolution lake temperature measurements (2 min, 15 depths) show different lake responses to atmospheric forcings: (1) continuous diurnal oscillations in the temperature in the first 5 m of the lake, (2) occasional diurnal oscillations in the temperature at depths from 7 to 20 m, and (3) occasional surface and internal seiches. Due to the sloped lake bottom, surface seiches produced the high-frequency oscillations in the lake temperatures with periods of 9 min at depths from 9 to 17 m.
Erwin Rottler, Till Francke, Gerd Bürger, and Axel Bronstert
Hydrol. Earth Syst. Sci., 24, 1721–1740, https://doi.org/10.5194/hess-24-1721-2020, https://doi.org/10.5194/hess-24-1721-2020, 2020
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In the attempt to identify and disentangle long-term impacts of changes in snow cover and precipitation along with reservoir constructions, we employ a set of analytical tools on hydro-climatic time series. We identify storage reservoirs as an important factor redistributing runoff from summer to winter. Furthermore, our results hint at more (intense) rainfall in recent decades. Detected increases in high discharge can be traced back to corresponding changes in precipitation.
Bertram Boehrer, Wolf von Tümpling, Ange Mugisha, Christophe Rogemont, and Augusta Umutoni
Hydrol. Earth Syst. Sci., 23, 4707–4716, https://doi.org/10.5194/hess-23-4707-2019, https://doi.org/10.5194/hess-23-4707-2019, 2019
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Dissolved methane in Lake Kivu (East Africa) represents a precious energy deposit, but the high gas loads have also been perceived as a threat by the local population. Our measurements confirm the huge amount of methane and carbon dioxide present, but do not support the current theory of a significant recharge. Direct measurements of gas pressure indicate no imminent danger due to limnic eruptions. A continuous survey is mandatory to support responsible action during industrial exploitation.
André Chandesris, Kris Van Looy, Jacob S. Diamond, and Yves Souchon
Hydrol. Earth Syst. Sci., 23, 4509–4525, https://doi.org/10.5194/hess-23-4509-2019, https://doi.org/10.5194/hess-23-4509-2019, 2019
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We found that small dams in rivers alter the thermal regimes of downstream waters in two distinct ways: either only the downstream daily minimum temperatures increase, or both the downstream daily minimum and maximum temperatures increase. We further show that only two physical dam characteristics can explain this difference in temperature response: (1) residence time, and (2) surface area. These results may help managers prioritize efforts to restore the fragmented thermalscapes of rivers.
Giulia Valerio, Marco Pilotti, Maximilian Peter Lau, and Michael Hupfer
Hydrol. Earth Syst. Sci., 23, 1763–1777, https://doi.org/10.5194/hess-23-1763-2019, https://doi.org/10.5194/hess-23-1763-2019, 2019
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This paper provides experimental evidence of the occurrence of large and periodic movements induced by the wind at 95 m in depth in Lake Iseo, where a permanent chemocline is located. These movements determine vertical oscillations of the oxycline up to 20 m. Accordingly, in 3 % of the sediment area alternating redox conditions occur, which might force unsteady sediment–water fluxes. This finding has major implications for the internal matter cycle in Lake Iseo.
Georgiy Kirillin, Ilya Aslamov, Matti Leppäranta, and Elisa Lindgren
Hydrol. Earth Syst. Sci., 22, 6493–6504, https://doi.org/10.5194/hess-22-6493-2018, https://doi.org/10.5194/hess-22-6493-2018, 2018
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We have discovered transient appearances of strong turbulent mixing beneath the ice of an Arctic lake. Such mixing events increase heating of the ice base up to an order of magnitude and can significantly accelerate ice melting. The source of mixing was identified as oscillations of the entire lake water body triggered by strong winds over the lake surface. This previously unknown mechanism of ice melt may help understand the link between the climate conditions and the seasonal ice formation.
Peter O. Zavialov, Alexander S. Izhitskiy, Georgiy B. Kirillin, Valentina M. Khan, Boris V. Konovalov, Peter N. Makkaveev, Vadim V. Pelevin, Nikolay A. Rimskiy-Korsakov, Salmor A. Alymkulov, and Kubanychbek M. Zhumaliev
Hydrol. Earth Syst. Sci., 22, 6279–6295, https://doi.org/10.5194/hess-22-6279-2018, https://doi.org/10.5194/hess-22-6279-2018, 2018
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This paper reports the results of field surveys conducted in Lake Issyk-Kul in 2015–2017 and compares the present-day data with the available historical records. Our data do not confirm the reports of progressive warming of the deep Issyk-Kul waters as suggested in some previous publications. However, they do indicate a positive trend of salinity in the lake’s interior over the last 3 decades. An important newly found feature is a persistent salinity maximum at depths of 70–120 m.
Xin Luo, Xingxing Kuang, Jiu Jimmy Jiao, Sihai Liang, Rong Mao, Xiaolang Zhang, and Hailong Li
Hydrol. Earth Syst. Sci., 22, 5579–5598, https://doi.org/10.5194/hess-22-5579-2018, https://doi.org/10.5194/hess-22-5579-2018, 2018
David Eschbach, Laurent Schmitt, Gwenaël Imfeld, Jan-Hendrik May, Sylvain Payraudeau, Frank Preusser, Mareike Trauerstein, and Grzegorz Skupinski
Hydrol. Earth Syst. Sci., 22, 2717–2737, https://doi.org/10.5194/hess-22-2717-2018, https://doi.org/10.5194/hess-22-2717-2018, 2018
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In this study we show the relevance of an interdisciplinary study for improving restoration within the framework of a European LIFE+ project on the French side of the Upper Rhine (Rohrschollen Island). Our results underscore the advantage of combining functional restoration with detailed knowledge of past trajectories in complex hydrosystems. We anticipate our approach will expand the toolbox of decision-makers and help orientate functional restoration actions in the future.
Eddie W. Banks, Margaret A. Shanafield, Saskia Noorduijn, James McCallum, Jörg Lewandowski, and Okke Batelaan
Hydrol. Earth Syst. Sci., 22, 1917–1929, https://doi.org/10.5194/hess-22-1917-2018, https://doi.org/10.5194/hess-22-1917-2018, 2018
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This study used a portable 56-sensor, 3-D temperature array with three heat pulse sources to measure the flow direction and magnitude below the water–sediment interface. Breakthrough curves from each of the sensors were analyzed using a heat transport equation. The use of short-duration heat pulses provided a rapid, accurate assessment technique for determining dynamic and multi-directional flow patterns in the hyporheic zone and is a basis for improved understanding of biogeochemical processes.
Nicholas Voichick, David J. Topping, and Ronald E. Griffiths
Hydrol. Earth Syst. Sci., 22, 1767–1773, https://doi.org/10.5194/hess-22-1767-2018, https://doi.org/10.5194/hess-22-1767-2018, 2018
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This paper describes instances in the Grand Canyon study area and a laboratory experiment in which very high suspended-sediment concentrations result in incorrectly low turbidity recorded with a commonly used field instrument. If associated with the monitoring of a construction or dredging project, false low turbidity could result in regulators being unaware of environmental damage caused by the actually much higher turbidity.
Silvia Bersan, André R. Koelewijn, and Paolo Simonini
Hydrol. Earth Syst. Sci., 22, 1491–1508, https://doi.org/10.5194/hess-22-1491-2018, https://doi.org/10.5194/hess-22-1491-2018, 2018
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Backward erosion piping is the cause of a significant percentage of failures and incidents involving dams and river embankments. In the past 20 years fibre-optic Distributed Temperature Sensing (DTS) has proved to be effective for the detection of leakages and internal erosion in dams. This work investigates the effectiveness of DTS for monitoring backward erosion piping in river embankments. Data from a large-scale piping test performed on an instrumented dike are presented and discussed.
Thaine H. Assumpção, Ioana Popescu, Andreja Jonoski, and Dimitri P. Solomatine
Hydrol. Earth Syst. Sci., 22, 1473–1489, https://doi.org/10.5194/hess-22-1473-2018, https://doi.org/10.5194/hess-22-1473-2018, 2018
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Citizens can contribute to science by providing data, analysing them and as such contributing to decision-making processes. For example, citizens have collected water levels from gauges, which are important when simulating/forecasting floods, where data are usually scarce. This study reviewed such contributions and concluded that integration of citizen data may not be easy due to their spatio-temporal characteristics but that citizen data still proved valuable and can be used in flood modelling.
Jutta Metzger, Manuela Nied, Ulrich Corsmeier, Jörg Kleffmann, and Christoph Kottmeier
Hydrol. Earth Syst. Sci., 22, 1135–1155, https://doi.org/10.5194/hess-22-1135-2018, https://doi.org/10.5194/hess-22-1135-2018, 2018
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This paper is motivated by the need for more precise evaporation rates from the Dead Sea (DS) and methods to estimate and forecast evaporation. A new approach to measure lake evaporation with a station located at the shoreline, also transferable to other lakes, is introduced. The first directly measured DS evaporation rates are presented as well as applicable methods for evaporation calculation. These results enable us to further close the DS water budget and to facilitate the water management.
Pauline Leduc, Peter Ashmore, and Darren Sjogren
Hydrol. Earth Syst. Sci., 22, 1–11, https://doi.org/10.5194/hess-22-1-2018, https://doi.org/10.5194/hess-22-1-2018, 2018
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We show the utility of ground-based time-lapse cameras for automated monitoring of stream stage and flow characteristics. High-frequency flow stage, water surface width and other information on the state of flow can be acquired for extended time periods with simple local calibration using a low-cost time-lapse camera and a few simple field measurements for calibration and for automated image selection and sorting. The approach is a useful substitute or complement to the conventional stage data.
Christina Tecklenburg and Theresa Blume
Hydrol. Earth Syst. Sci., 21, 5043–5063, https://doi.org/10.5194/hess-21-5043-2017, https://doi.org/10.5194/hess-21-5043-2017, 2017
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We characterized groundwater–lake exchange patterns and identified their controls based on extensive field measurements. Our measurement design bridges the gap between the detailed local characterisation and low resolution regional investigations. Results indicated strong spatial variability in groundwater inflow rates: large scale inflow patterns correlated with topography and the groundwater flow field and small scale patterns correlated with grainsize distributions of the lake sediment.
H. J. Ilja van Meerveld, Marc J. P. Vis, and Jan Seibert
Hydrol. Earth Syst. Sci., 21, 4895–4905, https://doi.org/10.5194/hess-21-4895-2017, https://doi.org/10.5194/hess-21-4895-2017, 2017
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We tested the usefulness of stream level class data for hydrological model calibration. Only two stream level classes, e.g. above or below a rock in the stream, were already informative, particularly when the boundary was chosen at a high stream level. There was hardly any improvement in model performance when using more than five stream level classes. These results suggest that model based streamflow time series can be obtained from citizen science based water level class data.
Hidayat Hidayat, Adriaan J. Teuling, Bart Vermeulen, Muh Taufik, Karl Kastner, Tjitske J. Geertsema, Dinja C. C. Bol, Dirk H. Hoekman, Gadis Sri Haryani, Henny A. J. Van Lanen, Robert M. Delinom, Roel Dijksma, Gusti Z. Anshari, Nining S. Ningsih, Remko Uijlenhoet, and Antonius J. F. Hoitink
Hydrol. Earth Syst. Sci., 21, 2579–2594, https://doi.org/10.5194/hess-21-2579-2017, https://doi.org/10.5194/hess-21-2579-2017, 2017
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Hydrological prediction is crucial but in tropical lowland it is difficult, considering data scarcity and river system complexity. This study offers a view of the hydrology of two tropical lowlands in Indonesia. Both lowlands exhibit the important role of upstream wetlands in regulating the flow downstream. We expect that this work facilitates a better prediction of fire-prone conditions in these regions.
Kyutae Lee, Ali R. Firoozfar, and Marian Muste
Hydrol. Earth Syst. Sci., 21, 1863–1874, https://doi.org/10.5194/hess-21-1863-2017, https://doi.org/10.5194/hess-21-1863-2017, 2017
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Accurate estimation of stream/river flows is important in many aspects, including public safety during floods, effective uses of water resources for hydropower generation and irrigation, and environments. In this paper, we investigated a feasibility of the continuous slope area (CSA) method which measures dynamic changes in instantaneous water surface elevations, and the results showed promising capabilities of the suggested method for the accurate estimation of flows in natural streams/rivers.
Raphael Schneider, Peter Nygaard Godiksen, Heidi Villadsen, Henrik Madsen, and Peter Bauer-Gottwein
Hydrol. Earth Syst. Sci., 21, 751–764, https://doi.org/10.5194/hess-21-751-2017, https://doi.org/10.5194/hess-21-751-2017, 2017
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We use water level observations from the CryoSat-2 satellite in combination with a river model of the Brahmaputra River, extracting satellite data over a dynamic river mask derived from Landsat imagery. The novelty of this work is the use of the CryoSat-2 water level observations, collected using a complex spatio-temporal sampling scheme, to calibrate a hydrodynamic river model. The resulting model accurately reproduces water levels, without precise knowledge of river bathymetry.
Matthew T. Perks, Andrew J. Russell, and Andrew R. G. Large
Hydrol. Earth Syst. Sci., 20, 4005–4015, https://doi.org/10.5194/hess-20-4005-2016, https://doi.org/10.5194/hess-20-4005-2016, 2016
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Unmanned aerial vehicles (UAVs) have the potential to capture information about the earth’s surface in dangerous and previously inaccessible locations. Here we present a method whereby image acquisition and subsequent analysis have enabled the highly dynamic and oft-immeasurable hydraulic phenomenon present during high-energy flash floods to be quantified at previously unattainable spatial and temporal resolutions.
Ian Cartwright and Harald Hofmann
Hydrol. Earth Syst. Sci., 20, 3581–3600, https://doi.org/10.5194/hess-20-3581-2016, https://doi.org/10.5194/hess-20-3581-2016, 2016
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This paper uses the natural geochemical tracer Rn together with streamflow measurements to differentiate between actual groundwater inflows and water that exits the river, flows through the near-river sediments, and subsequently re-enters the river downstream (parafluvial flow). Distinguishing between these two components is important to understanding the water balance in gaining streams and in managing and protecting surface water resources.
Z. D. Wen, K. S. Song, Y. Zhao, J. Du, and J. H. Ma
Hydrol. Earth Syst. Sci., 20, 787–801, https://doi.org/10.5194/hess-20-787-2016, https://doi.org/10.5194/hess-20-787-2016, 2016
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The study indicated that CDOM in rivers had higher aromaticity, molecular weight, and vascular plant contribution than in terminal lakes in the Hulun Buir plateau, Northeast China. The autochthonous sources of CDOM in plateau waters were higher than in other freshwater rivers reported in the literature. Study of the optical–physicochemical correlations is helpful in the evaluation of the potential influence of water quality factors on non-water light absorption in plateau water environments.
C. Schwatke, D. Dettmering, W. Bosch, and F. Seitz
Hydrol. Earth Syst. Sci., 19, 4345–4364, https://doi.org/10.5194/hess-19-4345-2015, https://doi.org/10.5194/hess-19-4345-2015, 2015
J. Halder, S. Terzer, L. I. Wassenaar, L. J. Araguás-Araguás, and P. K. Aggarwal
Hydrol. Earth Syst. Sci., 19, 3419–3431, https://doi.org/10.5194/hess-19-3419-2015, https://doi.org/10.5194/hess-19-3419-2015, 2015
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We introduce a new online global database of riverine water stable isotopes (Global Network of Isotopes in Rivers) and evaluate its longer-term data holdings. A regionalized, cluster-based precipitation isotope model was used to compare measured to predicted isotope compositions of riverine catchments. The study demonstrated that the seasonal isotopic composition and variation of river water can be predicted, which will improve the application of water stable isotopes in rivers.
L. Schulte, J. C. Peña, F. Carvalho, T. Schmidt, R. Julià, J. Llorca, and H. Veit
Hydrol. Earth Syst. Sci., 19, 3047–3072, https://doi.org/10.5194/hess-19-3047-2015, https://doi.org/10.5194/hess-19-3047-2015, 2015
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A 2600-year long composite palaeoflood record is reconstructed from high-resolution delta plain sediments of the Hasli-Aare floodplain on the northern slope of the Swiss Alps. Natural proxies compiled from sedimentary, geochemical and geomorphological data were calibrated by textual and factual sources and instrumental data. Geomorphological, historical and instrumental data provide evidence for flood damage intensities and discharge estimations of severe and catastrophic historical floods.
C. J. Gleason, L. C. Smith, D. C. Finnegan, A. L. LeWinter, L. H Pitcher, and V. W. Chu
Hydrol. Earth Syst. Sci., 19, 2963–2969, https://doi.org/10.5194/hess-19-2963-2015, https://doi.org/10.5194/hess-19-2963-2015, 2015
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Here, we give a semi-automated processing workflow to extract hydraulic parameters from over 10,000 time-lapse images of the remote Isortoq River in Greenland. This workflow allows efficient and accurate (mean accuracy 79.6%) classification of images following an automated similarity filtering process. We also give an effective width hydrograph (a proxy for discharge) for the Isortoq using this workflow, showing the potential of this workflow for enhancing understanding of remote rivers.
I. Kogelbauer and W. Loiskandl
Hydrol. Earth Syst. Sci., 19, 1427–1438, https://doi.org/10.5194/hess-19-1427-2015, https://doi.org/10.5194/hess-19-1427-2015, 2015
M. Schirmer, J. Luster, N. Linde, P. Perona, E. A. D. Mitchell, D. A. Barry, J. Hollender, O. A. Cirpka, P. Schneider, T. Vogt, D. Radny, and E. Durisch-Kaiser
Hydrol. Earth Syst. Sci., 18, 2449–2462, https://doi.org/10.5194/hess-18-2449-2014, https://doi.org/10.5194/hess-18-2449-2014, 2014
A. Parvathi, X. Zhong, A. S. Pradeep Ram, and S. Jacquet
Hydrol. Earth Syst. Sci., 18, 1073–1087, https://doi.org/10.5194/hess-18-1073-2014, https://doi.org/10.5194/hess-18-1073-2014, 2014
A. Zlinszky and G. Timár
Hydrol. Earth Syst. Sci., 17, 4589–4606, https://doi.org/10.5194/hess-17-4589-2013, https://doi.org/10.5194/hess-17-4589-2013, 2013
B. Fournier, C. Guenat, G. Bullinger-Weber, and E. A. D. Mitchell
Hydrol. Earth Syst. Sci., 17, 4031–4042, https://doi.org/10.5194/hess-17-4031-2013, https://doi.org/10.5194/hess-17-4031-2013, 2013
Y.-C. Chen
Hydrol. Earth Syst. Sci., 17, 1951–1962, https://doi.org/10.5194/hess-17-1951-2013, https://doi.org/10.5194/hess-17-1951-2013, 2013
A. T. Rezende Filho, S. Furian, R. L. Victoria, C. Mascré, V. Valles, and L. Barbiero
Hydrol. Earth Syst. Sci., 16, 2723–2737, https://doi.org/10.5194/hess-16-2723-2012, https://doi.org/10.5194/hess-16-2723-2012, 2012
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Short summary
Accurate river flow measurements are essential for understanding river processes. This study evaluates the freely available software KLT-IV for automatic river surface velocity measurement. Analysing over 11 000 videos and comparing them with 274 traditional flow measurements, we find strong correlations (r² = 0.95–0.97) between KLT-IV and traditional methods. KLT-IV effectively estimates river flow with high accuracy, making it a valuable tool for autonomous water resource management.
Accurate river flow measurements are essential for understanding river processes. This study...
