Drake Passage

Drake Passage showing the boundary points A, B, C, D, E and F accorded by the Treaty of Peace and Friendship of 1984 between Chile and Argentina
Tourist expedition ship Akademik Ioffe sailing across the Drake Passage to Antarctica
Depth profile with salinity and temperature for surface water.

The Drake Passage (Spanish: Pasaje de Drake) or Mar de Hoces—Sea of Hoces—is the body of water between South America's Cape Horn and the South Shetland Islands of Antarctica. It connects the southwestern part of the Atlantic Ocean (Scotia Sea) with the southeastern part of the Pacific Ocean and extends into the Southern Ocean.

History

The passage receives its English-language name from the 16th-century English privateer Sir Francis Drake. Drake's only remaining ship, after having passed through the Strait of Magellan, was blown far south in September 1578. This incident implied an open connection between the Atlantic and Pacific oceans.

Half a century earlier, after a gale had pushed them south from the entrance of the Strait of Magellan, the crew of the Spanish navigator Francisco de Hoces thought they saw a land's end and possibly inferred this passage in 1525.[1] For this reason, some Spanish and Latin American historians and sources call it Mar de Hoces after Francisco de Hoces.

The first recorded voyage through the passage was that of Eendracht, captained by the Dutch navigator Willem Schouten in 1616, naming Cape Horn in the process.

Geography

The 800-kilometre (500 mi) wide passage between Cape Horn and Livingston Island is the shortest crossing from Antarctica to any other landmass. The boundary between the Atlantic and Pacific Oceans is sometimes taken to be a line drawn from Cape Horn to Snow Island (130 kilometres (81 mi) north of mainland Antarctica). Alternatively, the meridian that passes through Cape Horn may be taken as the boundary. Both boundaries lie entirely within the Drake Passage.

The other two passages around the extreme southern part of South America (though not going around Cape Horn as such), Strait of Magellan and Beagle Channel, are very narrow, leaving little room for a ship. They can also become icebound, and sometimes the wind blows so strongly no sailing vessel can make headway against it. Hence most sailing ships preferred the Drake Passage, which is open water for hundreds of miles, despite very rough conditions. The small Diego Ramírez Islands lie about 100 kilometres (62 mi) south-southwest of Cape Horn.

There is no significant land anywhere around the world at the latitudes of Drake Passage, which is important to the unimpeded flow of the Antarctic Circumpolar Current which carries a huge volume of water (about 600 times the flow of the Amazon River) through the Passage and around Antarctica.

Ships in the Passage are often good platforms for the sighting of whales, dolphins and seabirds including giant petrels, other petrels, albatrosses and penguins.

Geology

The passage is known to have been closed until around 41 million years ago[2] according to a chemical study of fish teeth found in oceanic sedimentary rock. Before the passage opened, the Atlantic and Pacific Oceans were separated entirely with Antarctica being much warmer and having no ice cap. The joining of the two great oceans started the Antarctic Circumpolar Current and cooled the continent significantly.

See also

References

  1. ↑ Oyarzun, Javier, Expediciones españolas al Estrecho de Magallanes y Tierra de Fuego, 1976, Madrid: Ediciones Cultura Hispánica ISBN 84-7232-130-4
  2. ↑ Helen Briggs (21 April 2006). "Fossil gives clue to big chill". BBC News. Retrieved 1 November 2007.

Media related to Drake Passage at Wikimedia Commons

Coordinates: 58°34′49″S 65°54′34″W / 58.58028°S 65.90944°W / -58.58028; -65.90944

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