Abstract
Owing to the rapid increase of European heat event occurrences over the past decades, the understanding of their physical drivers has become increasingly important for the scientific community. Recently, it has been shown that cold North Atlantic sea surface temperatures are strongly linked to European heat events such as in summers of 2015 and 2018. Thereby, an accurate representation of this mechanism in climate models is crucial for a more realistic European heat event simulation. Here, we investigate the mechanism by employing seven global coupled climate models, of which six models are embedded in the High Resolution Model Intercomparison Project. Our results show that, compared to the models with low-resolution versions, high-resolution ones simulate a more realistic relationship between North Atlantic sea surface temperatures and European summer temperature extremes. This is attributable to a better reproduction of the North Atlantic trough and the downstream ridge anomalies over central Europe. Improvements in high-resolution ocean configurations reduce the North Atlantic surface biases and improves air-sea interactions, thus having implications for the prediction and projection of climate extremes in the North Atlantic-European region.
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Data availability
The HighResMIP data is retrieved from and publicly accessible through https://esgf-node.ipsl.upmc.fr/search/cmip6-ipsl/. The ERA5 Reanalysis data is retrieved from and publicly accessible through https://cds.climate.copernicus.eu/datasets. The OA Flux data is retrieved from and publicly accessible through https://climatedataguide.ucar.edu/climate-data/.
Code availability
The analysis and production of all figures is performed using Python code as shown by Jupyter Notebooks, which are freely accessible on Github https://github.com/julian28295/HighResMIP_NA_SST_Euro_heat.
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Acknowledgements
We acknowledge the European Centre for Medium-Range Weather Forecasts (ECMWF) data server for the freely available reanalysis data. Further, we thank the Earth System Grid Federation (ESGF) archive for the freely available HighResMIP data, the National Centre for Atmospheric Research (NCAR) for the freely available OA Flux data and Torge Martin for providing the FOCI data. The work of J. Krüger for this publication was supported by the Hans-Ertel-Centre for Weather Research, funded by the German Federal Ministry for Transportation and Digital Infrastructure (grant number BMVI/DWD 4823DWDP1B). J.Krüger, K.L. and D.M. receive funding for the research of this work from JPI Climate & JPI Oceans (ROADMAP, grant number 01LP2002C). K.L. and D.M. are provided with support from the European Union (Horizon Europe) project IMPETUS4CHANGE (grant number 101081555).
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J. Krüger designed the analysis, produced the figures and wrote the manuscript. J.Kjellsson designed the analysis and contributed with helpful comments to the manuscript. K.L. provided data for the analysis and contributed together with D.M. and R.P.K. with helpful comments to the manuscript.
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Communications Earth and Environment thanks the anonymous reviewers for their contribution to the peer review of this work. Primary Handling Editors: ChenRui Diao. [A peer review file is available].
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Krüger, J., Kjellsson, J., Lohmann, K. et al. Improved European heat event simulation in eddy-resolving climate models. Commun Earth Environ (2026). https://doi.org/10.1038/s43247-025-03145-9
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DOI: https://doi.org/10.1038/s43247-025-03145-9
