For the ATMOS part of the project, a correction system was implemented in the Max-Planck
Institute Earth System Model in its low resolution version (MPI-ESM-LR), that was successfully
used in the Kiel Climate Model (KCM) previously. The correction method had to be modified
compared to the KCM and, for example, the use of surface flux correction was not necessary
in the MPI-ESM-LR. The correction system now removes the North Atlantic cold bias in the
MPI-ESM and leads to a more realistic path of the North Atlantic current. However, the
corrected model has less power on decadal and longer timescales so that, for example, the
Atlantic Multidecadal Variability (AMV) appears less realistic than in the uncorrected model. In
the KCM on the other hand, the simulation of the AMV was improved compared to the
uncorrected model. A further aspect of the ATMOS part was the analysis of a high resolution
model of the North Atlantic available in Kiel. As well as pointing to the importance of the deep
circulation in the shaping the North Atlantic cold bias in models, the results show the role of
advection by the mean flow for shielding the Labrador Sea from the rest of the North Atlantic
leading to the formation of the so-called Lavender recirculation gyre (Wang et al., 2017).