We used the Massachusetts Institute of Technology general circulation model (MITgcm; Marshall et al.
[1997]), coupled to the sea ice model of Losch et al. [2010]. Our model domain (Figure 1a) was extracted
from a conformally mapped expanded spherical cube projection [Adcroft et al., 2004]. The grid consists of
840 by 1000 cells with a mean horizontal grid spacing of 1 km, which is much smaller than the local
Rossby radius of deformation of 6–10 km. The 1 km grid spacing is also required to allow adequate resolution of steep bottom topography where slopes can exceed 0.3, e.g., between moorings M1 and M2
(Figure 1a). The vertical discretization uses 80 levels with thickness exponentially increasing with depth
from 5 m at the surface to 30 m at 500 m and 80 m at 2000 m. Such relatively high horizontal and vertical resolution enables us to resolve the small-scale shelf-slope dynamical processes associated with the
complex and often extremely steep bathymetry of the South Scotia Ridge.