This work was supported in part through funding received from project INTAROS, funded by the European Union (Grant 727890). We thank NCEP for offering the NCEP-RA1 atmosphere reanalysis data (
https://psl.noaa.gov/ ). We also thank the Met Office, C3S, BGEP, and NABOS for sharing in-situ profiles and mooring observations. The ocean-sea ice reanalysis presented here is available at
https://catalog-intaros.nersc.no/dataset/ocean-sea-ice-synthesis-from-2007-2016. The model simulations were performed at the Deutsches Klimarechenzentrum (DKRZ), Hamburg, Germany. Contribution to the DFG funded Excellence Cluster CLICCS at the Center for Earth System Research and Sustainability of the University of Hamburg