The idea that basin-like dynamics may influence or control the Antarctic Circumpolar Current (ACC) is investigated with idealized analytic and numerical models. A simple 2-layer analytic model is developed to predict the transport evolution with the wind stress amplitude. At very low forcing, a non-zero minimum is predicted. This is followed by two distinct dynamical regimes for stronger forcing: a linearly increasing Stommel regime and a saturation regime in which the transport ceases to increase. The vertical distribution of the flow obtained using the geometry of the geostrophic contours (or characteristics) is key to predicting the occurrence of this transport saturation.;Experiments investigating the relative roles of the wind stress and wind stress curl in Drake Passage latitudes are also carried out. It is found that the transport is increased when adding a significant constant wind stress. In this regime dominated by the wind stress itself, there is an offset between the numerical results and what is predicted by the analytic model. The vertical momentum flux by mesoscale eddies can be used to distinguish between different regimes: an upward momentum transfer is observed when the dynamics is dominated by the wind stress curl and a downward flux is observed when it is not. In the regime where the wind stress curl dominates, Sverdrup circulation applies over most of the domain --- even in absence of meridional barriers. Also in this regime, transport is saturated, as suggested by the analytic model.;The analytic model is also generalized to a continuous stratification and numerical experiments varying the vertical resolution are carried out to test its robustness. These simulations show that the 2-layer and 5-layer models give equivalent results when inertial effects are weak. However, in the 5-layer simulations, topographically-driven inertial recirculations blocking Drake Passage reduce the transport when inertial effects are strong. This behavior disapears, however, when realistic topography is used. In this context, the numerical results agree well with the predictions of the analytic model. It is also found that when the wind stress curl dominates, meridional walls play an important role in the dynamics at weak forcing but become less and less important as the forcing increases.;Many eddy-permitting numerical simulations in large domains are carried over a wide range of parameters. The simulations using a reference zonal wind stress profile agree qualitatively with the analytic model. However, quantitative discrepancies are observed in the saturation regime: i) when a topographic continental ridge is added along the western boundary and ii) when the bottom drag is varied. When a continental ridge is added, eddy fluxes associated with zonal jets enhance the bottom layer recirculation and lower the saturation transport values. When the bottom drag is increased, the lower layer recirculation is suppressed, and this increases the saturation transport values.
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