The interannual variability of the Antarctic Circumpolar Current (ACC) transport in the Drake Passage is studied on the basis of simulations performed using the Argo-based model for Investigation of the Global Ocean (AMIGO), which consists of a block for variational interpolation of the Argo floats data to a regular grid and a block for model hydrodynamic adjustment of variationally interpolated fields. Such a technique allows us to obtain a complete set of oceanographic characteristics from irregularly located Argo measurements: temperature, salinity, density, and current velocity. The calculation results are presented as monthly, seasonal, and annual means and climatological fields. The mean ACC transport through the Drake Passage in 2005--2014 was estimated at $162 \pm 5$~Sv (1 Sv $= 10^6$~m$^3$~s$^{-1}$). Two additional numerical experiments were carried out in order to study the contribution of the wind forcing to the interannual variability of the ACC transport: the real thermohaline fields corresponding to the particular time period were replaced by climatic ones (Experiment~1); the real wind forcing data were replaced by the climatic ones (Experiment~2). Analysis of the results of numerical experiments has shown that variable wind stress forcing is the key factor controlling the interannual variability of the ACC transport through the Drake Passage.
Antarctic Circumpolar Current, transport, variability, modeling, Argo floats
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