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Standing meanders along the Antarctic Circumpolar Current (ACC) have been shown to be regions of elevated eddy variability, meridional heat transport, and vertical exchange. In this study, we investigate the influence of a standing meander south of Australia on air‐sea heat fluxes, upper ocean structure, and subduction in the 1/10° ACCESS‐OM2 ocean‐sea ice model forced by the JRA55 atmospheric reanalysis. We track the model's Subantarctic and Polar Fronts based on their jet and water mass structure, and produce composites of thermodynamical and dynamical properties of the meander in relaxed and flexed states. The standing meander induces trough‐to‐crest variations in surface heat flux, mixed layer depth (MLD), wind stress curl, vertical velocity, and subduction. At the crests, the ocean loses heat and the mixed layer is deeper; at the troughs, the ocean gains heat and the mixed layer is shallower. Wind stress curl, vertical velocity, and subduction change sign on entering and exiting crests and troughs. Vertical velocity due to the curvature of the meander is an order of magnitude larger than Ekman vertical velocity. The poleward excursion of Polar Front meander crests extends subduction to Antarctic Intermediate Water density classes. Finally, flexing of the meander enhances both air‐sea exchange and vertical velocity. The results show that standing meanders of the ACC influence the distribution and magnitude of air‐sea fluxes of heat and momentum and exchange between the surface and interior ocean. Plain Language Summary: Meanders along the Antarctic Circumpolar Current (ACC) funnel heat toward Antarctica. The research clarifies how meandering of ocean currents shapes air‐sea interaction and the transfer of surface ocean properties into the ocean interior in the ACC south of Australia. Meanders refer to curved patterns in the ACC's flow. We track specific ACC features and look at what is different inside and outside the meander in a computer model. We find that ocean meanders shape where the Southern Ocean gains and loses heat. These changes in heat exchange shape the mixed layer depth (MLD) in the ocean. The MLD is important for climate, biology productivity, and absorption of heat and carbon by the ocean. Meandering produces stronger vertical motion and increases sinking of water from the surface into the ocean interior, compared to regions where meanders are not present. When the meander flexes and becomes more curved, the vertical motion and atmosphere‐ocean exchange become even stronger. The results show that small‐scale patterns in ocean flow can have a strong influence on the atmosphere, with implications for climate and ocean circulation. These patterns are not well represented in climate models and our study is a step toward accounting for their absence. Key Points: Meanders in the Antarctic Circumpolar Current are locations of enhanced vertical velocity and air‐sea exchange of momentum and heatFlexing of the meander further enhances air‐sea exchange and vertical velocities due to increased curvaturePoleward excursion of meander crests extends subduction to Antarctic Intermediate Water densities along the Polar Front [ABSTRACT FROM AUTHOR]

Abstract: This study evaluates the capability of eddy‐permitting regional ocean models to reproduce the interocean exchange south of Africa. In this highly turbulent region, we show that the vertical structure of the horizontal flows need to be appropriately resolved to realistically advect thermocline water masses into the South Atlantic. Our results point out that a grid‐spacing of 1/24° on the horizontal and 50 m on the vertical homogeneously distributed are required to account for a correct transport of surface and subsurface water masses properties and their in‐route transformation by mixing. Preliminary Lagrangian analyses highlight the primary role of the upper‐ocean mesoscale eddies on water masses transport and fate, with a particular emphasis on Antarctic Intermediate Waters (AAIWs) dynamics and characteristics. We evaluate the numerical results against observations (AVISO data and Argo floats profiles). Modeled and observed eddies were examined in number, polarity, size, trajectory, and for their contribution to AAIW properties. A clear asymmetry, in number and radius, emerges between cyclones and anticyclones. The high‐resolution simulation was the most energetic, with more abundant and smaller structures than those detected in AVISO. However, eddy statistics compare reasonably well in terms of mean pathways when restricted to Agulhas Rings, which are on average quasi‐Gaussian in shape. Regionally, the Ertel potential vorticity anomaly is marked at the surface by a temporal variability with winter intensification, directly reflected in the seasonal cycle of the eddies number. Noting the growth of the baroclinic Rossby radius in winter, this suggests baroclinic processes as essential for these eddies generation. [ABSTRACT FROM AUTHOR]