Articles | Volume 22, issue 2
https://doi.org/10.5194/os-22-761-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-22-761-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Mar 2026
Research article |
| 04 Mar 2026
| 04 Mar 2026
Response of a semi-enclosed sea to perturbed freshwater and open ocean salinity forcing
Department of Research and Development, Swedish Meteorological and Hydrological Institute, 601 76 Norrköping, Sweden
Magnus Hieronymus
Department of Research and Development, Swedish Meteorological and Hydrological Institute, 601 76 Norrköping, Sweden
Per Pemberton
Department of Research and Development, Swedish Meteorological and Hydrological Institute, 601 76 Norrköping, Sweden
Department of Research and Development, Swedish Meteorological and Hydrological Institute, 601 76 Norrköping, Sweden
Sam T. Fredriksson
Department of Research and Development, Swedish Meteorological and Hydrological Institute, 601 76 Norrköping, Sweden
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Acoustic and satellite observations of turbulent ship wakes show that ships can mix the water column down to 30 m depth and that a temperature signature of the wake can last for tens of kilometres after ship passage. Turbulent wakes deeper than 12 m were frequently detected, which is deeper than previously reported. The observed extent of turbulent ship wakes implies that in areas with intensive ship traffic, ship mixing should be considered when assessing environmental impacts from shipping.
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Short summary
Climate change influences estuaries and their ecosystems not only by rising temperatures but also by salinity changes. This modeling study highlights the magnitude and causes of the Baltic Sea salinity sensitivity to fresh water forcing and changed ocean salinity. The large sensitivity to increased fresh water forcing is shown to be caused by dilution of fresh water within the estuary, recirculation of much of the outflow water back into the estuary, as well as decreasing inflows of ocean water.
Climate change influences estuaries and their ecosystems not only by rising temperatures but...
