Articles | Volume 29, issue 23
https://doi.org/10.5194/hess-29-7127-2025
© 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-29-7127-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 Dec 2025
Research article |
| 12 Dec 2025
| 12 Dec 2025
Field-scale modelling reveals dynamic groundwater flow and transport patterns in a high-energy subterranean estuary
Janek Greskowiak
CORRESPONDING AUTHOR
Working group Hydrogeology and Landscape Hydrology, Institute of Biology and Environmental Science & Institute for Chemistry and Biology of the Marine Environment (ass.), Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
Rena Meyer
Working group Hydrogeology and Landscape Hydrology, Institute of Biology and Environmental Science & Institute for Chemistry and Biology of the Marine Environment (ass.), Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
Jairo Cueto
Coastal Geology and Sedimentology Group, Institute of Geosciences, Kiel University, Kiel, Germany
Research Group in Natural and Exact Sciences – GICNEX, Department of Natural and Exact Sciences, Universidad de la Costa, Barranquilla, Colombia
Nico Skibbe
LIAG Institute for Applied Geophysics, Hannover, Germany
Anja Reckhardt
Working group Marine Isotope Geochemistry, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
Thomas Günther
LIAG Institute for Applied Geophysics, Hannover, Germany
Institute of Geophysics and Geoinformatics, TU Bergakademie Freiberg, Freiberg, Germany
Stephan L. Seibert
Working group Hydrogeology and Landscape Hydrology, Institute of Biology and Environmental Science & Institute for Chemistry and Biology of the Marine Environment (ass.), Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
Kai Schwalfenberg
Working group Marine Sensor Systems, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
Dietmar Pommerin
Working group Marine Sensor Systems, Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
Mike Müller-Petke
LIAG Institute for Applied Geophysics, Hannover, Germany
Gudrun Massmann
Working group Hydrogeology and Landscape Hydrology, Institute of Biology and Environmental Science & Institute for Chemistry and Biology of the Marine Environment (ass.), Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
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Short summary
Mixing of fresh groundwater and circulating seawater below beaches triggers water-rock chemical reactions and may affect coastal water quality. The subsurface of so-called high-energy beaches that are exposed to high tides, waves and storm floods are understudied as monitoring under these conditions is difficult. For the first time, this study quantifies the subsurface flow and mixing processes of a high-energy beach with the help of computer simulations based on an extensive set of field data.
Mixing of fresh groundwater and circulating seawater below beaches triggers water-rock chemical...
