Articles | Volume 21, issue 5
https://doi.org/10.5194/os-21-2505-2025
© Author(s) 2025. 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/os-21-2505-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
20 Oct 2025
Research article |
| 20 Oct 2025
| 20 Oct 2025
Amplified warming and marine heatwaves in the North Sea under a warming climate and their impacts
Bayoumy Mohamed
CORRESPONDING AUTHOR
GeoHydrodynamics and Environment Research (GHER), University of Liège, Liège, Belgium
Oceanography Department, Faculty of Science, Alexandria University, 21500 Alexandria, Egypt
Alexander Barth
GeoHydrodynamics and Environment Research (GHER), University of Liège, Liège, Belgium
Dimitry Van der Zande
Operational Directorate Natural Environment, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
Aida Alvera-Azcárate
GeoHydrodynamics and Environment Research (GHER), University of Liège, Liège, Belgium
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Earth-observing satellites provide routine measurement of several ocean parameters. However, these datasets have a significant amount of missing data due to the presence of clouds or other limitations of the employed sensors. This paper describes a method to infer the value of the missing satellite data based on a convolutional autoencoder (a specific type of neural network architecture). The technique also provides a reliable error estimate of the interpolated value.
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We present the first dedicated satellite salinity product in the Black Sea. We use the measurements provided by the European Soil Moisture and Ocean Salinity mission. We introduce enhanced algorithms for dealing with the contamination produced by the Radio Frequency Interferences that strongly affect this basin. We also provide a complete quality assessment of the new product and give an estimated accuracy of it.
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Short summary
We quantified the role of climate change and internal variability in marine heatwaves (MHWs) in the North Sea over more than 4 decades (1982–2024). A key finding is the 2013 climate shift, which was associated with increased warming and MHWs. Long-term warming accounted for 80 % of the observed trend in MHW frequency. The most intense MHW event in May 2024 was attributed to an anomalous anticyclonic atmospheric circulation. We also explored the impact of MHWs on chlorophyll concentration.
We quantified the role of climate change and internal variability in marine heatwaves (MHWs) in...
