A report on Southern Ocean and Drake Passage

The Antarctic Ocean, as delineated by the draft 4th edition of the International Hydrographic Organization's Limits of Oceans and Seas (2002)

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

A general delineation of the Antarctic Convergence, sometimes used by scientists as the demarcation of the Southern Ocean

Tourist expedition ship sailing across the Drake Passage to Antarctica

The International Hydrographic Organization's delineation of the "Southern Ocean" has moved steadily southwards since the original 1928 edition of its Limits of Oceans and Seas.

"Southern Ocean" as alternative to the Aethiopian Ocean, 18th century

The Drake Passage (middle of image) in relation to the global thermohaline circulation [ (animation)]

The plot shows an yearly average (2020) of the surface current strength (from GODAS dataset), together with streamlines. Following the streamlines, it is easy to see that the current is not closed in itself but interacts with the other ocean basins (connecting them). The Drake Passage plays a major role in this mechanism.

Water circulates around the globe as if it was on a conveyor belt. The Drake Passage is the narrowest channel, and its shape (width, depth and bottom roughness) strongly affects the global circulation.

Area inside the black line indicates the area constituting the Pacific Ocean prior to 2002; darker blue areas are its informal current borders following the recreation of the Southern Ocean and the reinclusion of marginal seas

The Drake Passage influences the global surface temperature and Atlantic circulation. With a closed Drake Passage, there is no Antarctic Circumpolar Current (as the Pacific and Atlantic are not connected), no North Atlantic Deep Water cell, the Southern Hemisphere is warmer and the Northern Hemisphere is colder. Gradually deepening the Drake Passage, a lighter ACC appears, but with a DP of 690m depth there is still no NADW, and the Northern Hemisphere is still colder. Only with the current shape (width and depth) of the Drake Passage the Southern Hemisphere is cold enough for the Antarctic Ice Sheet to appear, and the Atlantic Circulation is strong enough for the Northern Hemisphere to warm. (adapted from [Sijp and England, 2003] )

Continents and islands of the Southern Ocean

Density (buoyancy) drives an internal circulation only if the denser (colder or saltier) water mass lays above the less dense (warmer or less salty) one. In absence of any perturbation, the fluid assumes a stratified form. Neglecting salinity differences, the only possible drivers of such a circulation is vertical temperature differences. However, water gets heated and cooled at the same level, namely at the surface at the equator and at the surface at the poles. The force that pushes colder water above warmer water is internal mixing, which is more intense in presence of rough topography, such as in the Drake Passage.

A map of Australia's official interpretation of the names and limits of oceans and seas around Australia

Rough seas are common in the Drake Passage

1564 Typus Orbis Terrarum, a map by Abraham Ortelius showed the imagined link between the proposed continent of Antarctica and South America.

Tourists watch whales in the Drake Passage

Portrait of Edmund Halley by Godfrey Kneller (before 1721)

Seabird (light-mantled sooty albatross) flying over the Drake Passage

"Terres Australes" (sic) label without any charted landmass

Humpback whales are a common sight in the Drake Passage

James Weddell's second expedition in 1823, depicting the brig and the cutter Beaufroy

Hourglass dolphins leaping in the Passage

Famous official portrait of Captain James Cook who proved that waters encompassed the southern latitudes of the globe. "He holds his own chart of the Southern Ocean on the table and his right hand points to the east coast of Australia on it."

Drake Passage or Mar de Hoces between South America and Antarctica

USS Vincennes at Disappointment Bay, Antarctica in early 1840.

1911 South Polar Regions exploration map

Frank Hurley, As time wore on it became more and more evident that the ship was doomed ( trapped in pack ice), National Library of Australia.

MS Explorer in Antarctica in January 1999. She sank on 23 November 2007 after hitting an iceberg.

Seas that are parts of the Southern Ocean

An iceberg being pushed out of a shipping lane by (L to R) USS Burton Island (AGB-1), USS Atka (AGB-3), and USS Glacier (AGB-4) near McMurdo Station, Antarctica, 1965

The Antarctic Circumpolar Current (ACC) is the strongest current system in the world oceans, linking the Atlantic, Indian and Pacific basins.

Orca (Orcinus orca) hunting a Weddell seal in the Southern Ocean

A wandering albatross (Diomedea exulans) on South Georgia

Fish of the Notothenioidei suborder, such as this young icefish, are mostly restricted to the Antarctic and Subantarctic

Weddell seals (Leptonychotes weddellii) are the most southerly of Antarctic mammals.

Antarctic krill (Euphausia superba) are a keystone species of the food web.

A female warty squid (Moroteuthis ingens)

An adult and sub-adult Minke whale are dragged aboard the Japanese whaling vessel

Severe cracks in an ice pier in use for four seasons at McMurdo Station slowed cargo operations in 1983 and proved a safety hazard.

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.

- Drake Passage

The new delineation of seas being subdivisions of oceans has avoided the need to interrupt the northern boundary of the Southern Ocean where intersected by Drake Passage which includes all of the waters from South America to the Antarctic coast, nor interrupt it for the Scotia Sea, which also extends below the 60th parallel south.

- Southern Ocean

5 related topics with Alpha

Antarctic Peninsula

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Northernmost part of mainland Antarctica.

Location of the Antarctic Peninsula within Antarctica

Booth Island and Mount Scott flank the narrow Lemaire Channel on the west side of the Antarctic Peninsula, 2001

Off the coast of the Peninsula are numerous islands. Here is Webb Island and, behind it, Adelaide Island. See the image description page for a detailed description of the other geographical features.

German research vessel RV Polarstern at the wharf of the British Rothera Research Station

Nearly cloud-free view of the northern tip of the Antarctic Peninsula during Spring

Glaciomarine sedimentation at the margin of an ice-covered continent during interglacial

The Antarctic fur seal, once reduced to a small population on South Georgia after being hunted towards extinction, has returned to the waters around the Antarctic Peninsula.

Tierra del Fuego, the southernmost tip of South America, is about 1000 km away across the Drake Passage.

Seabirds of the Southern Ocean and West Antarctica found on the peninsula include: southern fulmar (Fulmarus glacialoides), the scavenging southern giant petrel (Macronectes giganteus), Cape petrel (Daption capense), snow petrel (Pagodroma nivea), the small Wilson's storm-petrel (Oceanites oceanicus), imperial shag (Phalacrocorax atriceps), snowy sheathbill (Chionis alba), the large south polar skua (Catharacta maccormicki), brown skua (Catharacta lönnbergi), kelp gull (Larus dominicanus), and Antarctic tern (Sterna vittata).

Scotia Sea

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Approximate area of the sea in the Southern Hemisphere

Map of Scotia Sea. Toponyms: Undersea relief, maritime, nearby lands, countries and cities. Isobath interval: 2000 m

The Scotia Sea is a sea located at the northern edge of the Southern Ocean at its boundary with the South Atlantic Ocean.

It is bounded on the west by the Drake Passage and on the north, east, and south by the Scotia Arc, an undersea ridge and island arc system supporting various islands.

Livingston Island

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Eastern Byers Peninsula with Urvich Wall and Rotch Dome in the background; a carpet of Usnea antarctica lichen in the foreground

Cooler mountains: The Sphinx in front of Lyaskovets Peak

Antarctic hairgrass, the world's southernmost flowering plant

Williams Point, discovered on 19 February 1819

Derelict Norwegian whaling boat on Half Moon Island

Livingston on George Powell's 1822 chart; the track is that of his sloop Dove in November 1821

Devils Point and Hell Gates, with Morton Strait and Snow Island in the background, and Smith Island on the right horizon

Mount Friesland, with Presian Ridge in the foreground and The Synagogue in the left background

Huron Glacier with Atanasoff Nunatak on the left and Delchev Peak on the right, McFarlane Strait with Moon Bay and Half Moon Island, and Greenwich Island in the background

Bransfield Strait with Antarctic Peninsula in the background, Peshev Ridge, Brunow Bay and Needle Peak in the middle ground, and Catalunyan Saddle in the foreground

Cámara Base (Argentina) with Livingston Island in the background

Guillermo Mann Base (Chile, left) and Cape Shirreff Field Station (USA, right)

Livingston Island map on a souvenir sheet

Geography of the thriller novel
The Killing Ship by Simon Beaufort

Hurd Peninsula and Rozhen Peninsula from Hannah Point

Antarctic pearlwort, one of the two native flowering plants

Kubrat Knoll, Inott Point and Edinburgh Hill

Tangra Mountains from Chilean and US base vicinity

Livingston Island (Russian name Smolensk, -62.6°N, -60.5°W) is an Antarctic island in the Southern Ocean, part of the South Shetlands Archipelago, a group of Antarctic islands north of the Antarctic Peninsula.

The island is part of the South Shetlands archipelago, an islands chain extending 510 km in east-northeast to west-southwest direction, and separated from the nearby Antarctic Peninsula by Bransfield Strait, and from South America by the Drake Passage.

Antarctic Circumpolar Current

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Ocean current that flows clockwise (as seen from the South Pole) from west to east around Antarctica.

The Antarctic Circumpolar Current is the strongest current system in the world oceans and the only ocean current linking all major oceans: the Atlantic, Indian, and Pacific Oceans. Seawater density fronts after.

The ACC (red circle near the middle of the image) in relation to the global thermohaline circulation [ (animation)]

The Falkland Current transports nutrient-rich cold waters from the ACC north toward the Brazil–Malvinas Confluence. Phytoplankton chlorophyll concentration are shown in blue (lower concentrations) and yellow (higher concentrations).

The ACC is the dominant circulation feature of the Southern Ocean and has a mean transport estimated at 100–150 Sverdrups (Sv, million m3/s), or possibly even higher, making it the largest ocean current.

To trace it starting arbitrarily at South America, it flows through the Drake Passage between South America and the Antarctic Peninsula and then is split by the Scotia Arc to the east, with a shallow warm branch flowing to the north in the Falkland Current and a deeper branch passing through the Arc more to the east before also turning to the north.

Fiann Paul

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Icelandic explorer, athlete, artist, speaker and Jungian psychoanalyst.

"Dialog", large-scale, outdoor art installation in 2008

"See It", large-scale, outdoor art installation in 2011

Timelapse of endurance hunting presented by Fiann Paul during TEDx talk.

Fiann has crossed all five oceans in an unsupported human-powered row boat with world-record-breaking speed, setting the overall speed records for the Atlantic, Indian, Pacific and Arctic Ocean (he achieved the only human-powered crossing of the Antarctic Ocean and as a result no speed record was adjudicated due to lack of competition).

In 2019 Fiann Paul led the first human-powered transit (by rowing) across the Drake Passage, and the first human-powered expedition on the Southern Ocean.