Drake Passage

Drake Passage
GMT (OMC) base map modified by Giovanni Fattori · CC BY-SA 3.0 · source
Name	Drake Passage
Location	Southern Ocean
Type	Channel
Basin countries	Argentina; Chile

Drake Passage The Drake Passage lies between the southern tip of South America and Antarctica, linking the Atlantic Ocean with the Pacific Ocean and forming a key part of the Southern Ocean. It is a major conduit for the Antarctic Circumpolar Current, influences global thermohaline circulation, and has played a decisive role in the history of exploration and marine science.

Geography and boundaries

The Passage separates Cape Horn on Tierra del Fuego and Isla Grande de Tierra del Fuego from South Shetland Islands and Antarctic Peninsula features such as Graham Land. Its northern approaches include the waters off Beagle Channel and the Falkland Islands, while southern limits border Bransfield Strait and the shelf seas adjacent to South Orkney Islands. Territorial proximity involves Chile and Argentina with nearby claims overlapping Antártica Chilena Province and zones referenced by British Antarctic Territory and Argentine Antarctica interests. Shipping routes connect ports like Punta Arenas, Ushuaia, Port Stanley, and transit lanes to Cape Town and Hobart, Tasmania.

Geology and oceanography

The opening of the Passage resulted from plate motions involving the South American Plate, Antarctic Plate, and fragments such as the Scotia Plate during the Cenozoic, a tectonic evolution linked to rifting events contemporaneous with the formation of the Drake Fault and back-arc dynamics near the Andean orogeny. Bathymetry includes the deep South Scotia Ridge, submarine troughs, and seafloor features mapped by expeditions from vessels like RV Polarstern and institutions such as the British Antarctic Survey. Oceanographically it is dominated by the Antarctic Circumpolar Current, Southern Ocean fronts including the Polar Front and Subantarctic Front, and by water masses like Antarctic Intermediate Water and Circumpolar Deep Water that influence global Meridional Overturning Circulation. Eddy fields, mesoscale jets, and internal waves have been studied by programs at Scripps Institution of Oceanography and Lamont–Doherty Earth Observatory.

Climate and weather patterns

Weather in the Passage is shaped by the interaction of Westerlies with the Southern Ocean and the influence of large-scale modes such as the Southern Annular Mode and El Niño–Southern Oscillation. The region experiences frequent low-pressure systems tied to the Roaring Forties and Furious Fifties, producing intense cyclones that drive high seas and strong winds documented by meteorological services including Met Office and Servicio Meteorológico Nacional (Argentina). Sea ice variability relates to phenomena studied by National Snow and Ice Data Center and agencies like National Oceanic and Atmospheric Administration. Extreme waves measured by buoys deployed by National Institute of Water and Atmospheric Research and satellites from European Space Agency have informed understanding of storm-driven ocean dynamics.

Marine life and ecosystems

The Passage supports rich ecosystems including krill dependent webs involving Antarctic krill (Euphausia superba), pelagic predators such as blue whale, humpback whale, southern right whale, and apex foragers including orca. Seabird assemblages include albatrosses like wandering albatross, petrels such as snow petrel, and penguin species including Adélie penguin and chinstrap penguin nesting on nearby islands. Benthic communities on continental shelves harbor sponges, corals, and echinoderms surveyed by teams from Monterey Bay Aquarium Research Institute and museums like Natural History Museum, London. Food web dynamics have been central to research by Commission for the Conservation of Antarctic Marine Living Resources and programs assessing impacts from commercial whaling and industrial fishing.

Human history and exploration

European awareness followed voyages by explorers associated with Sir Francis Drake and later navigators including James Cook and Falklands-era mariners, while sealing and whaling fleets from Great Britain, United States, Norway, and Argentina operated in proximate waters. 19th-century sealing expeditions out of ports such as Port Stanley and Valparaiso were succeeded by scientific voyages like HMS Challenger (1872–1876) and exploratory missions by Robert Falcon Scott-era programs. The Passage became a regular route for 20th-century voyages by research vessels from institutions including Scripps Institution of Oceanography, British Antarctic Survey, Instituto Antártico Chileno, and naval operations of Royal Navy and United States Navy supporting bases like Rothera Research Station and Marambio Base.

Shipping, navigation, and hazards

Mariners face hazards including extreme seas, rogue waves, icebergs calved from Larsen Ice Shelf and Antarctic Peninsula glaciers, and limited search-and-rescue assets; national authorities like Compañía Sudamericana de Vapores and cruise operators from Hurtigruten and Quark Expeditions plan routes accordingly. Navigational aids include satellite services from Inmarsat and Iridium Communications and charts produced by offices such as the United Kingdom Hydrographic Office and Servicio Hidrográfico y Oceanográfico de la Armada de Chile. The Passage is a critical segment for commercial traffic linking routes between Cape Horn passages and global shipping lanes to Panama Canal alternatives; incidents like historical shipwrecks highlighted by archives at Maritime Museum of Tasmania emphasize risk management.

Conservation and scientific research

Conservation measures are informed by treaties and organizations such as the Antarctic Treaty System, Convention on the Conservation of Antarctic Marine Living Resources, and scientific programs funded by national agencies including National Science Foundation (United States), Consejo Nacional de Ciencia y Tecnología (CONACYT), and European Commission research initiatives. Long-term monitoring by platforms like ARGO floats, remote sensing from satellites operated by NASA and European Space Agency, and field studies supported by institutes including British Antarctic Survey, Scripps Institution of Oceanography, and Australian Antarctic Division address climate change, biodiversity, and ocean acidification. Conservationists and researchers collaborate with non-governmental organizations such as World Wildlife Fund and BirdLife International to assess impacts of fisheries managed under Commission for the Conservation of Antarctic Marine Living Resources protocols.

Category:Channels of the Southern Ocean Category:Bodies of water of Chile Category:Bodies of water of Argentina