The Drake Passage, South America to Antarctica

Drake Passage, deep waterway, 600 miles (1,000 km) wide, connecting the Atlantic and Pacific oceans between Cape Horn (the southernmost point of South America) and the South Shetland Islands, situated about 100 miles (160 km) north of the Antarctic Peninsula. The Drake Passage defines the zone of climatic transition separating the cool, humid, subpolar conditions of Tierra del Fuego and the frigid, polar regions of Antarctica. Though bearing the name of the famous English seaman and global circumnavigator Sir Francis Drake, the passage was first traversed in 1616.

The passage has an average depth of about 11,000 feet (3,400 metres) with deeper regions of up to 15,600 feet (4,800 metres) near the northern and southern boundaries. The sediments on the seafloor vary from sandy to clayey silts immediately south of Tierra del Fuego, with an increasing predominance of ice-rafted materials (dropped by icebergs) near Antarctica.

The winds over the Drake Passage are predominantly from the west and are most intense to the north around Cape Horn. Cyclones (atmospheric low pressure systems) formed in the Pacific sweep west to east across the southern edge of the passage. The mean annual air temperature ranges from 41 °F (5 °C) in the north to 27 °F (−3 °C) in the south. Surface water temperatures vary from 43 °F (6 °C) in the north to 30 °F (−1 °C) in the south, with the temperatures altering sharply around latitude 60° S—the zone of the Antarctic Convergence.