 In its positive phase, the westerly wind belt that drives the Antarctic Circumpolar Current intensifies and contracts towards Antarctica, while its negative phase the belt moves towards the Equator.Winds associated with the Antarctic oscillation cause oceanic upwelling of warm circumpolar deep water along the Antarctic continental shelf.This has been linked to ice shelf basal melt, representing a possible wind-driven mechanism that could destabilize large portions of the Antarctic Ice Sheet.