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
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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.
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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.
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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...
