While the circumpolar current is the dominant feature of the Southern Ocean, there are other important flows in the north-south direction and in the vertical plane. The average depth of the ocean ranges from 2,000 to 4,000 metres.he temperature of the water in the Southern Ocean has a powerful influence on the climate of much of the earth. The current is not always stable. It can develop disturbances called waves or eddies which involve the entire water column.