Here's why:
* Surface currents are driven by wind patterns. These winds are influenced by the Coriolis effect, which causes them to be deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.
* At the poles, the Coriolis effect is at its strongest. This means that surface currents are deflected strongly towards the east in the Southern Hemisphere. However, there isn't a physical barrier like a continent or a mountain range that would cause a significant deflection at the South Pole itself.
* The convergence of currents at the South Pole forms the Antarctic Circumpolar Current (ACC). This powerful current flows eastward around Antarctica and is a major influence on the global ocean circulation.
Therefore, the deflection of surface currents at the South Pole is primarily due to the strong Coriolis effect, leading to the formation of the ACC. There isn't a specific "thing" that deflects the currents at the South Pole itself.
