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V. Maurer et al.: Evaluation of coupled and uncoupled simulations 
20 
—— Insitu data | 
— Reanalysis 
— NEMO NBS 
— ROAM NBS | 
Competing interests. The contact author has declared that none of 
the authors has any competing interests. 
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Disclaimer. Publisher’s note: Copernicus Publications remains 
neutral with regard to jJurisdictional claims made in the text, pub- 
lished maps, institutional affiliations, or any other geographical rep- 
resentation in this paper. The authors bear the ultimate responsibil- 
ity for providing appropriate place names. Views expressed in the 
text are those of the authors and do not necessarily reflect the views 
of the publisher. 
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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 
Figure A10. Seasonal climatology (continuous) and correspond- 
.ng 90th percentile threshold (dashed) computed for the location 
Leuchtturm Kiel in the western Baltic Sea from in-situ data at 
0.5 m depth (black). NEMO-NBS simulation (blue) and ROAM- 
NBS simulation (green) and Copernicus Reanalysis (orange). Com- 
mon climatological period is 1993 to 2020. 
Acknowledgements. We acknowledge the contributions by 
E. Maisonnave (CERFACS/IPSL) within the project IS-ENES 
funded by the European Union’s Horizon 2020 research and 
innovation programme under grant agreement no. 824084. 
We acknowledge Carsten Viergutz and Claudius Fleischer from 
ıhe Bundesanstalt für Gewässerkunde (BfG) for providing the 
runoff dataset, and Lars Axell from the Swedish Meteorological and 
Hydrological Institute (SMHI) for supplying hindcast data used in 
he ocean model initialization. 
This work used resources of the Deutsches Klimarechenzen- 
ırum (DKRZ) granted by its Scientific Steering Committee (WLA) 
under project ID bb1338. DWD and BSH are associated partners of 
Coastal Futures. ChatGPT and Perplexity were used to support the 
writing of evaluation scripts. We acknowledge the E-OBS dataset 
from the EU-FP6 project UERRA (http://www.uverra.eu, last ac- 
cess: 6 January 2026) and the data providers in the ECA&D project 
(https:/www.ecad.eu., last access: 6 January 2026). 
Code and data availability. For ICON, the open-source release 
2024.07 was used: https://gitlab.dkrz.de/icon/icon-model/-/tree/ 
release-2024.07-public (last access: 15 July 2025) and ICON part- 
a1ership (2024); see also https://www.icon-model.org/ (last access: 
19 September 2025) for further reference. The model version in- 
cluding OASIS3-MCT interfaces can be accessed at https://github. 
com/vmaurerDWD/icon-ROAM. For NEMO, the open-source re- 
lease 4.2.0 was used (https://forge.nemo-ocean.eu/nemo/nemo/-/ 
:ree/4.2.0, last access: 15 July 2025). All source codes (ICON, 
NEMO, OASIS3-MCT, and XIOS) are additionally stored on 
Zenodo (https://doi.org/10.5281/zenodo. 17035585; Meyer et al., 
2025a). Run scripts and configurations necessary to perform the 
ICON-CLM, NEMO-NBS, and the coupled simulation are also 
available on Zenodo (https://doi.org/10.5281/zenodo.17037353; 
Meyer et al., 2025b). Necessary input data for a short time period 
and additional post-processing scripts can be found under the same 
resource. 
DWD station data are available via CDC (https: 
//cdc.dwd.de/portal/, last access: 6 January 2026). Mea- 
surement data of FINO1 are freely available after registra- 
jon via https://www.bsh.de/DE/DATEN/Klima-und-Meer/ 
Meeresumweltmessnetz/_Module/Info_Stationen/info_fino1_node. 
html (last access: 15 July 2025). E-OBS data v27.0 were obtained 
from https://surfobs.climate.copernicus.eu/dataaccess/access_eobs. 
php#datafiles (last access: 15 July 2025). 
Financial support. The project CoastalFutures-2, on which the 
contribution by two of the co-authors of this publication is based, 
was funded by Germany’s Federal Ministry of Research, Technol- 
ogy and Space (BMFTR). 
Review statement. "This paper was edited by Sophie Valcke and re- 
viewed by two anonymous referees 
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