111-731: The Ross Sea is a deep bay of the Southern Ocean in Antarctica , between Victoria Land and Marie Byrd Land and within the Ross Embayment , and is the southernmost sea on Earth. It derives its name from the British explorer James Clark Ross who visited this area in 1841. To the west of the sea lies Ross Island and Victoria Land, to the east Roosevelt Island and Edward VII Peninsula in Marie Byrd Land, while
222-463: A Northwest Passage to "the Western and Southern Ocean of America ". Authors using "Southern Ocean" to name the waters encircling the unknown southern polar regions used varying limits. James Cook 's account of his second voyage implies New Caledonia borders it. Peacock's 1795 Geographical Dictionary said it lay "to the southward of America and Africa"; John Payne in 1796 used 40 degrees as
333-440: A submerged continent , continental fragment , and microcontinent . The name and concept for Zealandia was proposed by Bruce Luyendyk in 1995, and satellite imagery shows it to be almost the size of Australia. A 2021 study suggests Zealandia is over a billion years old, about twice as old as geologists previously thought. By approximately 23 million years ago, the landmass may have been completely submerged. Today, most of
444-523: A billion years ago and sources from an expanded-Ur continent between 3.5 and 2 billion years ago. The breakup of Gondwana formed Northern Zealandia. Zealandia underwent extension resulting from east to northeast-directed rollback of west to southwest-dipping subduction of the Pacific Plate . which terminated between 95 million to 85 million years ago. After 85 million years ago Zealandia separated from Australia through seafloor spreading of
555-658: A captain in the Russian Imperial Navy ; Edward Bransfield , a captain in the Royal Navy ; and Nathaniel Palmer , an American sailor out of Stonington, Connecticut . It is certain that the expedition, led by von Bellingshausen and Lazarev on the ships Vostok and Mirny , reached a point within 32 km (20 mi) from Princess Martha Coast and recorded the sight of an ice shelf at 69°21′28″S 2°14′50″W / 69.35778°S 2.24722°W / -69.35778; -2.24722 that became known as
666-544: A coincident decrease in the number of orcas. The report recommended a full moratorium on fishing over the Ross shelf. In October 2012, Philippa Ross, James Ross' great, great, great granddaughter, voiced her opposition to fishing in the area. In the southern winter of 2017 New Zealand scientists discovered the breeding ground of the Antarctic toothfish in the northern Ross Sea seamounts for the first time underscoring how little
777-462: A land in 50° S which he called South France, and believed to be the central mass of the southern continent. He was sent out again to complete the exploration of the new land, and found it to be only an inhospitable island which he renamed the Isle of Desolation, but which was ultimately named after him . The obsession of the undiscovered continent culminated in the brain of Alexander Dalrymple ,
888-545: A microcontinent, Zealandia would be the world's largest microcontinent. Its area is six times the area of the next-largest microcontinent, Madagascar , and more than half the area of the Australian continent . Zealandia is more than twice the size of the largest intraoceanic large igneous province (LIP) in the world, the Ontong Java Plateau (approximately 1,900,000 km or 730,000 sq mi), and
999-528: A note in the publication read: The Antarctic or Southern Ocean has been omitted from this publication as the majority of opinions received since the issue of the 2nd Edition in 1937 are to the effect that there exists no real justification for applying the term Ocean to this body of water, the northern limits of which are difficult to lay down owing to their seasonal change. The limits of the Atlantic, Pacific and Indian Oceans have therefore been extended South to
1110-748: A proposal for a Ross Sea MPA at the September 2012 meeting of the CCAMLR . At this stage, a sustained campaign by various international and national NGOs commenced to accelerate the process. In July 2013, the CCAMLR held a meeting in Bremerhaven in Germany, to decide whether to turn the Ross Sea into an MPA. The deal failed due to Russia voting against it, citing uncertainty about whether the commission had
1221-698: A stratigraphy for most of the older glacial sequences, which comprise Oligocene and younger sediments. The Ross Sea-wide major unconformity RSU-6 has been proposed to mark a global climate event and the first appearance of the Antarctic Ice Sheet in the Oligocene. During 2018, Expedition 374 of the International Ocean Discovery Program (IODP), the latest successor to the DSDP, drilled additional holes (U1521–1525) in
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#17327650582931332-701: Is 286,660.25 km (110,680.14 sq mi). Of this, New Zealand comprises the overwhelming majority, at 267,988 km (103,471 sq mi, or 93.49%) that includes the mainland ( North Island and South Island ), nearby islands, and most outlying islands , including the Chatham Islands , the New Zealand Subantarctic Islands , the Solander Islands , and the Three Kings Islands (but not
1443-480: Is a relatively warm, salty and nutrient-rich water mass that flows onto the continental shelf at certain locations. The Ross Sea is covered with ice for most of the year. The nutrient-laden water supports an abundance of plankton and this encourages a rich marine fauna. At least ten mammal species, six bird species and 95 fish species are found here, as well as many invertebrates, and the sea remains relatively unaffected by human activities. New Zealand has claimed that
1554-446: Is about 500 meters. It is shallower in the western Ross Sea (east longitudes) than the east (west longitudes). This over-deepened condition is due to cycles of erosion and deposition of sediments from expanding and contracting ice sheets overriding the shelf during Oligocene and later time, and is also found on other locations around Antarctica. Erosion was more focused on the inner parts of the shelf while deposition of sediment dominated
1665-623: Is at the northern end of the ancient continent, while New Zealand rises at the plate boundary that bisects it. These land masses constitute two outposts of the Antarctic flora , featuring araucarias and podocarps . At Curio Bay , logs of a fossilized forest closely related to modern kauri and Norfolk pine can be seen that grew on Zealandia approximately 180 million years ago during the Jurassic period, before it split from Gondwana. The trees growing in these forests were buried by volcanic mud flows and gradually replaced by silica to produce
1776-528: Is known about the species. On 28 October 2016, at its annual meeting in Hobart , a Ross Sea marine park was declared by the CCAMLR, under an agreement signed by 24 countries and the European Union . It protected over 1.5 million square kilometers of sea and was the world's largest protected area at the time. However, a sunset provision of 35 years was part of negotiations, which means it does not meet
1887-405: Is regarded by marine biologists as having a very high biological diversity and as such has a long history of human exploration and scientific research, with some datasets going back over 150 years. The Ross Sea is home to at least 10 mammal species, half a dozen species of birds, 95 species of fish, and over 1,000 invertebrate species. Some species of birds that nest in and near the Ross Sea include
1998-558: Is restricted to the Victoria Land Basin and Northern Basin. Basement grabens are filled with rift sediments of uncertain character and age. A widespread unconformity has cut into the basement and sedimentary fill of the large basins. Above this major unconformity (named RSU-6) are a series of glacial marine sedimentary units deposited during multiple advances and retreats of the Antarctic Ice Sheet across
2109-476: Is thinner than usual, approximately 20 km (12 mi) thick, and consequently, they do not float so high above Earth's mantle as that of most landmasses. About 25 million years ago, the southern part of Zealandia (on the Pacific Plate ) began to shift relative to the northern part (on the Indo-Australian Plate ). The resulting displacement by approximately 500 km (310 mi) along
2220-419: Is usually free of ice during the summer. The southernmost part of the Ross Sea is Gould Coast , which is approximately 200 miles (320 km) from the geographic South Pole . The Ross Sea (and Ross Ice Shelf ) overlies a deep continental shelf . Although the average depth of the world's continental shelves (at the shelf break joining the continental slope) is about 130 meters, the Ross shelf average depth
2331-628: Is widespread across Zealandia, but on present land generally it is of low volume apart from the huge mid to late Miocene shield volcanoes that developed the Banks and Otago Peninsulas . In addition, it took place continually in numerous limited regions all through the Late Cretaceous and the Cenozoic . Some of its causes remain in dispute perhaps because of data gaps. During the Miocene ,
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#17327650582932442-597: The Adélie penguin , emperor penguin , Antarctic petrel , snow petrel , and south polar skua . Marine mammals in the Ross Sea include the Antarctic minke whale , killer whale , Weddell seal , crabeater seal , and leopard seal . Antarctic toothfish , Antarctic silverfish , Antarctic krill , and crystal krill also swim in the cold Antarctic water of the Ross Sea. The flora and fauna are considered similar to other southern Antarctic marine regions. Particularly in Summer,
2553-751: The Alpine Fault is evident in geological maps. Movement along this plate boundary also has offset the New Caledonia Basin from its previous continuation through the Bounty Trough . Compression across the boundary has uplifted the Southern Alps , although due to rapid erosion their height reflects only a small fraction of the uplift. Farther north, subduction of the Pacific Plate has led to extensive volcanism, including
2664-593: The Antarctic Ocean , comprises the southernmost waters of the world ocean , generally taken to be south of 60° S latitude and encircling Antarctica . With a size of 21,960,000 km (8,480,000 sq mi), it is the second-smallest of the five principal oceanic divisions, smaller than the Pacific , Atlantic and Indian oceans, and larger than the Arctic Ocean . The maximum depth of
2775-514: The Coral and Tasman seas until this ceased 52 million years ago. Shortening on an active convergent northern margin of Zealandia occurred mainly between 45 and 35 million years ago. This was followed by the opening of the backarc basins of the southwest Pacific and the migration of the Tonga and Kermadec Trenchs to the east. Shear extrusion followed between 23.3 million to 5 million years ago with
2886-617: The Coromandel and Taupo Volcanic Zones . Associated rifting and subsidence has produced the Hauraki Rift and more recently, the Whakatane Graben and Wanganui Basin. Volcanism on Zealandia has taken place repeatedly in various parts of the continental fragment before, during, and after it rifted away from the supercontinent Gondwana . Although Zealandia has shifted approximately 6,000 km (3,700 mi) to
2997-796: The Cretaceous suggesting extreme stretching of the Ross Embayment during that time. Marie Byrd Land – Rocks exposed in western Marie Byrd Land on the Edward VII Peninsula and within the Ford Ranges are candidates for basement in the eastern Ross Sea. The oldest rocks are Permian sediments of the Swanson Formation, which is slightly metamorphosed. The Ford granodiorite of Devonian age intrudes these sediments. Cretaceous Byrd Coast granite in turn intrudes
3108-694: The Ferarr volcanic rocks of Jurassic age are separated from the Ross Supergroup by the Kukri Peneplain . Beacon rocks are reported to have been recovered in the drill cores of the Cape Roberts Project at the western edge of the Ross Sea. The Ross Sea circulation, dominated by polynya processes, is in general very slow-moving. Circumpolar Deep Water (CDW) is a relatively warm, salty and nutrient-rich water mass that flows onto
3219-586: The Fimbul Ice Shelf . On 30 January 1820, Bransfield sighted Trinity Peninsula , the northernmost point of the Antarctic mainland, while Palmer sighted the mainland in the area south of Trinity Peninsula in November 1820. Von Bellingshausen's expedition also discovered Peter I Island and Alexander I Island , the first islands to be discovered south of the circle. In December 1839, as part of
3330-516: The Great South Basin were issued in 2007. Offshore mineral resources include ironsands , volcanic massive sulfides and ferromanganese nodule deposits. GNS Science recognises two names for the landmass. In English, the most common name is Zealandia , a latinate name for New Zealand; the name was coined in the mid-1990s and became established through common use. In the Māori language ,
3441-675: The International Union for Conservation of Nature definition of a marine protected area , which requires it to be permanent. Beginning in 2005, the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) commissioned scientific analysis and planning for Marine Protected Areas (MPA) in the Antarctic. In 2010, the CCAMLR endorsed their Scientific Committee's proposal to develop Antarctic MPAs for conservation purposes. The US State Department submitted
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3552-590: The Kermadec Islands or Macquarie Island ( Australia ), which are parts of the rift). New Caledonia and the islands surrounding it comprise some 18,576 km (7,172 sq mi or 6.48%) and the remainder is made up of various territories of Australia including the Lord Howe Island Group ( New South Wales ) at 56 km (22 sq mi or 0.02%), Norfolk Island at 35 km (14 sq mi or 0.01%), as well as
3663-503: The Southern Ocean Observing System . The Ross Sea is one of the last stretches of seas on Earth that remains relatively unaffected by human activities. Consequently, the Ross Sea has become a focus of numerous environmentalist groups who have campaigned to make the area a world marine reserve, citing the rare opportunity to protect the Ross Sea from a growing number of threats and destruction. The Ross Sea
3774-627: The Strait of Magellan in 1520, assumed that the islands of Tierra del Fuego to the south were an extension of this unknown southern land. In 1564, Abraham Ortelius published his first map, Typus Orbis Terrarum , an eight-leaved wall map of the world, on which he identified the Regio Patalis with Locach as a northward extension of the Terra Australis , reaching as far as New Guinea . European geographers continued to connect
3885-598: The Transantarctic Mountains on the western side of the Ross Sea are possible basement rock below the sedimentary cover of the sea floor. The rocks are of upper Precambrian to lower Paleozoic in age, deformed in many places during the Ross Orogeny in the Cambrian . These miogeosyncline metasedimentary rocks are partly composed of calcium carbonate , often including limestone . Groups within
3996-709: The United States Exploring Expedition of 1838–42 conducted by the United States Navy (sometimes called "the Wilkes Expedition"), an expedition sailed from Sydney, Australia, on the sloops-of-war USS Vincennes and USS Peacock , the brig USS Porpoise , the full-rigged ship Relief , and two schooners Sea Gull and USS Flying Fish . They sailed into the Antarctic Ocean, as it
4107-687: The parallel 60° south latitude was discovered by the Englishman William Smith , who sighted Livingston Island on 19 February 1819. A few months later Smith returned to explore the other islands of the South Shetlands archipelago, landed on King George Island , and claimed the new territories for Britain. In the meantime, the Spanish Navy ship San Telmo sank in September 1819 when trying to cross Cape Horn. Parts of her wreckage were found months later by sealers on
4218-399: The "South Land" – described by a half legendary " sieur de Gonneyville " – resulted in the discovery of Bouvet Island in 54°10′ S, and in the navigation of 48° of longitude of ice-cumbered sea nearly in 55° S in 1730. In 1771, Yves Joseph Kerguelen sailed from France with instructions to proceed south from Mauritius in search of "a very large continent". He lighted upon
4329-608: The 16th and the early part of the 17th centuries. The Spaniard Gabriel de Castilla , who claimed having sighted "snow-covered mountains" beyond the 64° S in 1603, is recognized as the first explorer that discovered the continent of Antarctica, although he was ignored in his time. In 1606, Pedro Fernández de Quirós took possession for the king of Spain all of the lands he had discovered in Australia del Espiritu Santo (the New Hebrides ) and those he would discover "even to
4440-514: The 2002 edition the limits of oceans explicitly excluded the seas lying within each of them. The Great Australian Bight was unnamed in the 1928 edition, and delineated as shown in the figure above in the 1937 edition. It therefore encompassed former Southern Ocean waters—as designated in 1928—but was technically not inside any of the three adjacent oceans by 1937. In the 2002 draft edition, the IHO have designated "seas" as subdivisions within "oceans", so
4551-548: The Antarctic Circle, or knew it, if they did. In a voyage from 1822 to 1824, James Weddell commanded the 160-ton brig Jane , accompanied by his second ship Beaufoy captained by Matthew Brisbane. Together they sailed to the South Orkneys where sealing proved disappointing. They turned south in the hope of finding a better sealing ground. The season was unusually mild and tranquil, and on 20 February 1823
Ross Sea - Misplaced Pages Continue
4662-557: The Antarctic Continent. Hydrographic Offices who issue separate publications dealing with this area are therefore left to decide their own northern limits (Great Britain uses Latitude of 55 South.) Instead, in the IHO 1953 publication, the Atlantic, Indian and Pacific Oceans were extended southward, the Indian and Pacific Oceans (which had not previously touched pre 1953, as per the first and second editions) now abutted at
4773-482: The Antarctic mix with warmer Subantarctic waters, or not defined at all, with its waters instead treated as the southern limits of the Pacific, Atlantic, and Indian oceans. The International Hydrographic Organization (IHO) finally settled the debate after the full importance of Southern Ocean overturning circulation had been ascertained, and the term Southern Ocean now defines the body of water which lies south of
4884-518: The Bight would have still been within the Southern Ocean in 1937 if the 2002 convention were in place then. To perform direct comparisons of current and former limits of oceans it is necessary to consider, or at least be aware of, how the 2002 change in IHO terminology for "seas" can affect the comparison. The Southern Ocean did not appear in the 1953 third edition of Limits of Oceans and Seas ,
4995-626: The CIA World Fact Book ) which already adopted the principle that seas are contained within oceans. This difference in practice is markedly seen for the Pacific Ocean in the adjacent figure. Thus, for example, previously the Tasman Sea between Australia and New Zealand was not regarded by the IHO as part of the Pacific, but as of the 2002 draft edition it is. The new delineation of seas as subdivisions of oceans has avoided
5106-487: The Eastern Basin, which has approximately the same width as the other three. The Coulman High separates the Victoria Land Basin and Central Trough and the Central High separates the Central Trough and Eastern Basin. The majority of the faulting and accompanying graben formation along with crustal extension occurred during the rifting away of the Zealandia microcontinent from Antarctica in Gondwana during Cretaceous time. Paleogene and Neogene -age and faulting and extension
5217-404: The National Geographic web site have begun to reference the Southern Ocean. A radical shift from past IHO practices (1928–1953) was also seen in the 2002 draft edition when the IHO delineated "seas" as subdivisions within the boundaries of "oceans". While the IHO are often considered the authority for such conventions, the shift brought them into line with the practices of other publications (e.g.
5328-419: The New Zealand Alpine Fault rupture and a southwestward extension of the Campbell Plateau relative to the Challenger Plateau . Southeast Indian Ocean Ridge expansion movement completely separated Zealandia from the Antarctic at about 10 million years ago. In the last 5 million years Zealandia has been generally subsiding owing to the Pacific Plate subducting westward and retreating eastward. New Caledonia
5439-487: The Pole". Francis Drake , like Spanish explorers before him, had speculated that there might be an open channel south of Tierra del Fuego. When Willem Schouten and Jacob Le Maire discovered the southern extremity of Tierra del Fuego and named it Cape Horn in 1615, they proved that the Tierra del Fuego archipelago was of small extent and not connected to the southern land, as previously thought. Subsequently, in 1642, Abel Tasman showed that even New Holland (Australia)
5550-487: The Priestley and Campbell glaciers. For thirty miles along the lower Skelton Glacier are the calcareous greywackes and argillites of the Skelton Group. The region between the lower Beardmore Glacier and the lower Shackelton Glacier sits the Beardmore Group. North of the Nimrod Glacier are four block faulted ranges that make up the Byrd Group. The contents of the Queen Maud Group area are mainly post-tectonic granite . Beacon Sandstone of Devonian - Triassic age and
5661-420: The Ross Sea is dominated by a wind-driven gyre . The flow is strongly influenced by three submarine ridges that run from southwest to northeast. Flow over the shelf below the surface layer consists of two anticyclonic gyres connected by a central cyclonic flow. The flow is considerable in spring and winter, due to influencing tides. The Ross Sea is covered with ice for much of the year and ice concentrations and in
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#17327650582935772-406: The Ross System include the Robertson Bay Group, Priestley Group, Skelton Group, Beardmore Group, Byrd Group, Queen Maud Group, and Koettlitz Group. The Robertson Bay Group compares closely with other Ross System members. The Priestley Group rocks are similar to those of the Robertson Bay Group and include dark slates, argillites , siltstones , fine sandstones and limestones. They can be found near
5883-593: The South Atlantic to the Cape of Good Hope between 55° and 60° . He thereby laid open the way for future Antarctic exploration by exploding the myth of a habitable southern continent. Cook's most southerly discovery of land lay on the temperate side of the 60th parallel , and he convinced himself that if land lay farther south it was practically inaccessible and without economic value. Voyagers rounding Cape Horn frequently met with contrary winds and were driven southward into snowy skies and ice-encumbered seas; but so far as can be ascertained none of them before 1770 reached
5994-420: The Southern Ocean as extending as far north as South America, and confers great significance on the Antarctic Convergence , yet its description of the Indian Ocean contradicts this, describing the Indian Ocean as extending south to Antarctica. Other sources, such as the National Geographic Society , show the Atlantic , Pacific , and Indian oceans as extending to Antarctica on its maps, although articles on
6105-411: The Southern Ocean as lying immediately south of Australia (see § Australian standpoint ). The National Geographic Society recognized the ocean officially in June 2021. Prior to this, it depicted it in a typeface different from the other world oceans; instead, it shows the Pacific, Atlantic, and Indian Oceans extending to Antarctica on both its print and online maps. Map publishers using
6216-508: The Southern Ocean was inspired by a belief in the existence of a Terra Australis – a vast continent in the far south of the globe to "balance" the northern lands of Eurasia and North Africa – which had existed since the times of Ptolemy . The rounding of the Cape of Good Hope in 1487 by Bartolomeu Dias first brought explorers within touch of the Antarctic cold, and proved that there was an ocean separating Africa from any Antarctic land that might exist. Ferdinand Magellan , who passed through
6327-506: The Southern Ocean, in an open boat called James Caird , and then trekked over South Georgia to raise the alarm at the whaling station Grytviken . Zealandia Zealandia (pronounced / z iː ˈ l æ n d i ə / ), also known as Te Riu-a-Māui ( Māori ) or Tasmantis (from Tasman Sea ), is an almost entirely submerged mass of continental crust in Oceania that subsided after breaking away from Gondwana 83–79 million years ago. It has been described variously as
6438-429: The Southern Ocean, using the definition that it lies south of 60th parallel, was surveyed by the Five Deeps Expedition in early February 2019. The expedition's multibeam sonar team identified the deepest point at 60° 28' 46"S, 025° 32' 32"W, with a depth of 7,434 metres (24,390 ft). The expedition leader and chief submersible pilot Victor Vescovo , has proposed naming this deepest point the "Factorian Deep", based on
6549-444: The Southern Ocean. In Australia, cartographical authorities define the Southern Ocean as including the entire body of water between Antarctica and the south coasts of Australia and New Zealand, and up to 60°S elsewhere. Coastal maps of Tasmania and South Australia label the sea areas as Southern Ocean and Cape Leeuwin in Western Australia is described as the point where the Indian and Southern Oceans meet. Exploration of
6660-598: The authority to establish a marine protected area. In October 2014, the MPA proposal was again defeated at the CCAMLR by votes against from China and Russia. At the October 2015 meeting a revised MPA proposal from the US and New Zealand was expanded with the assistance of China, who however shifted the MPA's priorities from conservation by allowing commercial fishing. The proposal was again blocked by Russia. [REDACTED] Media related to Ross Sea at Wikimedia Commons Southern Ocean Main five oceans division: Further subdivision: The Southern Ocean , also known as
6771-531: The authors presented geological and ecological evidence in support of their thesis. In 2017, a team of eleven geologists from New Zealand, New Caledonia, and Australia concluded that Zealandia fulfills all the requirements to be considered a submerged continent , rather than a microcontinent or continental fragment . This verdict was widely covered in the news media . The younger Zealandia rocks have evidence of origins from early Gondwana formations of 500 to 700 million years ago, Rodinia formations about
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#17327650582936882-460: The brilliant and erratic hydrographer who was nominated by the Royal Society to command the Transit of Venus expedition to Tahiti in 1769. The command of the expedition was given by the admiralty to Captain James Cook . Sailing in 1772 with Resolution , a vessel of 462 tons under his own command and Adventure of 336 tons under Captain Tobias Furneaux , Cook first searched in vain for Bouvet Island , then sailed for 20 degrees of longitude to
6993-413: The calm. The coastal parts of the sea contain a number of rookeries of Adélie and Emperor penguins, which have been observed at a number of places around the Ross Sea, both towards the coast and outwards in open sea. A 10-metre (32.8 feet) long colossal squid weighing 495 kilograms (1,091 lb) was captured in the Ross Sea on February 22, 2007. In 2010, the Ross Sea Antarctic toothfish fishery
7104-436: The central Ross Sea for determining Neogene and Quaternary ice sheet history. The nature of the basement rocks and the fill within the grabens are known in few locations. Basement rocks have been sampled at DSDP Leg 28 drill site 270 where metamorphic rocks of unknown age were recovered, and in the eastern Ross Sea where a bottom dredge was collected. In both these locations the metamorphic rocks are mylonites deformed in
7215-405: The circulation substantially slowing or even passing a tipping point and collapsing outright. The latter would have adverse impacts on global weather and the function of marine ecosystems here, unfolding over centuries. The ongoing warming is already changing marine ecosystems here. Borders and names for oceans and seas were internationally agreed when the International Hydrographic Bureau ,
7326-419: The coast of Tierra del Fuego with the coast of New Guinea on their globes, and allowing their imaginations to run riot in the vast unknown spaces of the south Atlantic, south Indian and Pacific oceans they sketched the outlines of the Terra Australis Incognita ("Unknown Southern Land"), a vast continent stretching in parts into the tropics. The search for this great south land was a leading motive of explorers in
7437-405: The continental shelf at certain locations in the Ross Sea. Through heat flux, this water mass moderates the ice cover. The near-surface water also provides a warm environment for some animals and nutrients to excite primary production. CDW transport onto the shelf is known to be persistent and periodic, and is thought to occur at specific locations influenced by bottom topography. The circulation of
7548-433: The discovery of which he had received news at Cape Town , but from the rough determination of his longitude by Kerguelen, Cook reached the assigned latitude 10° too far east and did not see it. He turned south again and was stopped by ice in 61° 52′ S by 95° E and continued eastward nearly on the parallel of 60° S to 147° E . On 16 March, the approaching winter drove him northward for rest to New Zealand and
7659-429: The expedition regained Tahiti for refreshment. In November 1774, Cook started from New Zealand and crossed the South Pacific without sighting land between 53° and 57° S to Tierra del Fuego; then, passing Cape Horn on 29 December, he rediscovered Roché Island renaming it Isle of Georgia , and discovered the South Sandwich Islands (named Sandwich Land by him), the only ice-clad land he had seen, before crossing
7770-431: The fossils now exposed by the sea. As sea levels drop during glacial periods, more of Zealandia becomes a terrestrial environment rather than a marine environment. Originally, it was thought that Zealandia had no native land mammal fauna, but the discovery in 2006 of a fossil mammal jaw from the Miocene in the Otago region demonstrates otherwise. The total land area (including inland water bodies ) of Zealandia
7881-410: The island in 1775. Edmond Halley 's voyage in HMS Paramour for magnetic investigations in the South Atlantic met the pack ice in 52° S in January 1700, but that latitude (he reached 140 mi [230 km] off the north coast of South Georgia ) was his farthest south. A determined effort on the part of the French naval officer Jean-Baptiste Charles Bouvet de Lozier to discover
7992-413: The landmass (94%) remains submerged beneath the Pacific Ocean . New Zealand is the largest part of Zealandia that is above sea level, followed by New Caledonia . Mapping of Zealandia concluded in 2023. With a total area of approximately 4,900,000 km (1,900,000 sq mi), Zealandia is substantially larger than any features termed microcontinents and continental fragments. If classified as
8103-529: The landmass is named Te Riu-a-Māui , meaning 'the hills, valleys, and plains of Māui '. The Zealandia continent is largely made up of two nearly parallel ridges, separated by a failed rift , where the rift breakup of the continent stops and becomes a filled graben . The ridges rise above the sea floor to heights of 1,000–1,500 m (3,300–4,900 ft), with a few rocky islands rising above sea level . The ridges are continental rock, but are lower in elevation than normal continents because their crust
8214-543: The latter of which contains most of the Median Batholith crust. These two features are separated by the Alpine Fault and Kermadec Trench and by the wedge-shaped Hikurangi Plateau , and they are moving separately from each other. The case for Zealandia being a continent in its own right has been argued in the Nick Mortimer and Hamish Campbell book Zealandia: Our continent revealed (2014), in which
8325-489: The meridian of South East Cape , and the southern limits of the Great Australian Bight and the Tasman Sea were moved northward. The IHO readdressed the question of the Southern Ocean in a survey in 2000. Of its 68 member nations, 28 responded, and all responding members except Argentina agreed to redefine the ocean, reflecting the importance placed by oceanographers on ocean currents . The proposal for
8436-534: The name Southern Ocean won 18 votes, beating the alternative Antarctic Ocean . Half of the votes supported a definition of the ocean's northern limit at the 60th parallel south —with no land interruptions at this latitude—with the other 14 votes cast for other definitions, mostly the 50th parallel south , but a few for as far north as the 35th parallel south . Notably the Southern Ocean Observing System collates data from latitudes higher than 40 degrees south. A draft fourth edition of Limits of Oceans and Seas
8547-490: The name of the crewed submersible DSV Limiting Factor , in which he successfully visited the bottom for the first time on February 3, 2019. By way of his voyages in the 1770s, James Cook proved that waters encompassed the southern latitudes of the globe. Yet, geographers have often disagreed on whether the Southern Ocean should be defined as a body of water bound by the seasonally fluctuating Antarctic Convergence - an oceanic zone where cold, northward flowing waters from
8658-525: 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. The new delineation of seas has also meant that the long-time named seas around Antarctica, excluded from the 1953 edition (the 1953 map did not even extend that far south), are automatically part of
8769-469: The north coast of Livingston Island ( South Shetlands ). It is unknown if some survivor managed to be the first to set foot on these Antarctic islands. The first confirmed sighting of mainland Antarctica cannot be accurately attributed to one single person. It can be narrowed down to three individuals. According to various sources, three men all sighted the ice shelf or the continent within days or months of each other: Fabian Gottlieb von Bellingshausen ,
8880-414: The northern limit of that circulation. The Southern Ocean overturning circulation is important because it makes up the second half of the global thermohaline circulation , after the better known Atlantic meridional overturning circulation (AMOC). Much like AMOC, it has also been substantially affected by climate change , in ways that have increased ocean stratification , and which may also result in
8991-485: The northern limit; the 1827 Edinburgh Gazetteer used 50 degrees. The Family Magazine in 1835 divided the "Great Southern Ocean" into the "Southern Ocean" and the "Antarctick [ sic ] Ocean" along the Antarctic Circle, with the northern limit of the Southern Ocean being lines joining Cape Horn, the Cape of Good Hope, Van Diemen's Land and the south of New Zealand. The United Kingdom's South Australia Act 1834 described
9102-566: The northern section of Zealandia ( Lord Howe Rise ) might have slid over a stationary hotspot , forming the Lord Howe Seamount Chain . It has been suggested that Zealandia may have played an important part in the origin of the Pacific Ocean's volcanic Ring of Fire . Occasionally, Zealandia is divided into two regions by scientists: North Zealandia (or Western Province); and South Zealandia (or Eastern Province),
9213-555: The northwest with respect to the underlying mantle from the time when it rifted from Antarctica , recurring intracontinental volcanism exhibits magma composition similar to that of volcanoes in previously adjacent parts of Antarctica and Australia. Large volume magmatism occurred in two periods, being in the Devonian (370 to 368 million years ago) and the Early Cretaceous (129 to 105 million years ago). This volcanism
9324-450: The nutrient-rich sea water supports an abundant planktonic life in turn providing food for larger species, such as fish , seals , whales , and sea- and shore- birds . Albatrosses rely on wind to travel and cannot get airborne in a calm. The westerlies do not extend as far south as the ice edge and therefore albatrosses do not travel often to the ice-pack. An albatross would be trapped on an ice floe for many days if it landed in
9435-586: The ocean and its definition as the waters south of the 60th parallel south in its 2000 revisions, but this has not been formally adopted, due to continuing impasses about some of the content, such as the naming dispute over the Sea of Japan . The 2000 IHO definition was circulated as a draft edition in 2002, and is used by some within the IHO and other organizations, such as the CIA World Factbook and Merriam-Webster . The Australian Government regards
9546-622: The ocean's northern limit ceased to abut land masses. In the second edition, the Southern Ocean then extended from Antarctica northward to latitude 40°S between Cape Agulhas in Africa (long. 20°E) and Cape Leeuwin in Western Australia (long. 115°E), and extended to latitude 55°S between Auckland Island of New Zealand (165 or 166°E east) and Cape Horn in South America (67°W). As is discussed in more detail below, prior to
9657-745: The older rocks. The Byrd Coast and older formations have been cut by basalt dikes . Scattered through the Ford Ranges and Fosdick Mountains are late Cenozoic volcanic rocks that are not found to the west on Edward VII Peninsula. Metamorphic rocks, migmatites , are found in the Fosdick Mountains and Alexandra Mountains . These were metamorphosed and deformed in the Cretaceous. The Ross Supergroup system and Beacon Supergroup – Ross System rocks exposed in Victoria Land and in
9768-496: The other new sea names within the "Southern Ocean", such as the " Cosmonauts Sea ") and Merriam-Webster , scientists and nations – and even by some within the IHO. Some nations' hydrographic offices have defined their own boundaries; the United Kingdom used the 55th parallel south for example. Other organisations favour more northerly limits for the Southern Ocean. For example, Encyclopædia Britannica describes
9879-529: The outer shelf, making the inner shelf deeper than the outer. Seismic studies in the latter half of the twentieth century defined the major features of the geology of the Ross Sea. The deepest or basement rocks, are faulted into four major north trending graben systems, which are basins for sedimentary fill. These basins include the Northern and Victoria Land Basin in the west, the Central Trough, and
9990-511: The precursor to the IHO, convened the First International Conference on 24 July 1919. The IHO then published these in its Limits of Oceans and Seas , the first edition being 1928. Since the first edition, the limits of the Southern Ocean have moved progressively southward; since 1953, it has been omitted from the official publication and left to local hydrographic offices to determine their own limits. The IHO included
10101-483: The requirements to be considered a continent rather than a microcontinent or continental fragment. Geologist Nick Mortimer commented that if it were not for the ocean level, it would have been recognised as such long ago. Zealandia supports substantial inshore fisheries and contains gas fields, of which the largest known is the New Zealand Maui gas field , near Taranaki . Permits for oil exploration in
10212-483: The sea comes under its jurisdiction as part of the Ross Dependency . Marine biologists consider the sea to have a high level of biological diversity and it is the site of much scientific research. It is also the focus of some environmentalist groups who have campaigned to have the area proclaimed as a world marine reserve. In 2016 an international agreement established the region as a marine park . The Ross Sea
10323-589: The sea floor of the Ross Sea during the Oligocene and later. Drill holes have recovered cores of rock from the western edges of the sea. The most ambitious recent efforts are the Cape Roberts Project (CRP) and the ANDRILL project. Deep Sea Drilling Project (DSDP) Leg 28 completed several holes (270–273) farther from land in the central and western portions of the sea. These resulted in defining
10434-552: The south, and South America, Africa, Australia, and Broughton Island, New Zealand to the north. The detailed land-limits used were from Cape Horn in Chile eastward to Cape Agulhas in Africa, then further eastward to the southern coast of mainland Australia to Cape Leeuwin , Western Australia . From Cape Leeuwin, the limit then followed eastward along the coast of mainland Australia to Cape Otway , Victoria , then southward across Bass Strait to Cape Wickham , King Island , along
10545-549: The south-central region little melting occurs. Ice concentrations in the Ross Sea are influenced by winds with ice remaining in the western region throughout the austral spring and generally melting in January due to local heating. This leads to extremely strong stratification and shallow mixed layers in the western Ross Sea. Observation and data access in the region is coordinated by the Ross Sea Working Group of
10656-727: The southernmost part is covered by the Ross Ice Shelf , and is about 200 miles (320 km) from the South Pole . Its boundaries and area have been defined by the New Zealand National Institute of Water and Atmospheric Research as having an area of 637,000 square kilometres (246,000 sq mi). The circulation of the Ross Sea is dominated by a wind-driven ocean gyre and the flow is strongly influenced by three submarine ridges that run from southwest to northeast. The circumpolar deep water current
10767-518: The term Southern Ocean on their maps include Hema Maps and GeoNova. "Southern Ocean" is an obsolete name for the Pacific Ocean or South Pacific, coined by the Spanish explorer Vasco Núñez de Balboa , the first European to discover the Pacific, who approached it from the north in Panama . The "South Seas" is a less archaic synonym. A 1745 British Act of Parliament established a prize for discovering
10878-524: The tropical islands of the Pacific. In November 1773, Cook left New Zealand, having parted company with the Adventure , and reached 60° S by 177° W , whence he sailed eastward keeping as far south as the floating ice allowed. The Antarctic Circle was crossed on 20 December and Cook remained south of it for three days, compelled after reaching 67° 31′ S to stand north again in 135° W . A long detour to 47° 50′ S served to show that there
10989-571: The two ships reached latitude 74°15' S and longitude 34°16'45″ W the southernmost position any ship had ever reached up to that time. A few icebergs were sighted but there was still no sight of land, leading Weddell to theorize that the sea continued as far as the South Pole. Another two days' sailing would have brought him to Coat's Land (to the east of the Weddell Sea ) but Weddell decided to turn back. The first land south of
11100-524: The waters forming the southern limit of the new province of South Australia as "the Southern Ocean". The Colony of Victoria 's Legislative Council Act 1881 delimited part of the division of Bairnsdale as "along the New South Wales boundary to the Southern ocean". In the 1928 first edition of Limits of Oceans and Seas , the Southern Ocean was delineated by land-based limits: Antarctica to
11211-567: The west coast of King Island, then the remainder of the way south across Bass Strait to Cape Grim , Tasmania . The limit then followed the west coast of Tasmania southward to the South East Cape and then went eastward to Broughton Island, New Zealand, before returning to Cape Horn. The northern limits of the Southern Ocean were moved southward in the IHO's 1937 second edition of the Limits of Oceans and Seas . From this edition, much of
11322-515: The westward in latitude 58° S , and then 30° eastward for the most part south of 60° S , a lower southern latitude than had ever been voluntarily entered before by any vessel. On 17 January 1773 the Antarctic Circle was crossed for the first time in history and the two ships reached 67° 15' S by 39° 35' E , where their course was stopped by ice. Cook then turned northward to look for French Southern and Antarctic Lands , of
11433-637: The world's largest island, Greenland (2,166,086 km or 836,330 sq mi). Zealandia is also substantially larger than the Arabian Peninsula (3,237,500 km or 1,250,000 sq mi), the world's largest peninsula , and the Indian subcontinent (4,300,000 km or 1,700,000 sq mi). Due to these and other geological considerations, such as crustal thickness and density, some geologists from New Zealand, New Caledonia, and Australia have concluded that Zealandia fulfills all
11544-451: Was changed. A reservation had also been lodged by Australia regarding the Southern Ocean limits. Effectively, the third edition—which did not delineate the Southern Ocean leaving delineation to local hydrographic offices—has yet to be superseded. Despite this, the fourth edition definition has partial de facto usage by many nations, scientists, and organisations such as the U.S. (the CIA World Factbook uses "Southern Ocean", but none of
11655-466: Was circulated to IHO member states in August 2002 (sometimes referred to as the "2000 edition" as it summarized the progress to 2000). It has yet to be published due to 'areas of concern' by several countries relating to various naming issues around the world – primarily the Sea of Japan naming dispute – and there have been various changes, 60 seas were given new names, and even the name of the publication
11766-548: Was discovered by the Ross expedition in 1841. In the west of the Ross Sea is Ross Island with the Mt. Erebus volcano ; in the east is Roosevelt Island . The southern part is covered by the Ross Ice Shelf . Roald Amundsen started his South Pole expedition in 1911 from the Bay of Whales , which was located at the shelf. In the western parts of the Ross Sea, McMurdo Sound is a port that
11877-636: Was independently certified by the Marine Stewardship Council, and has been rated as a 'Good Alternative' by the Monterey Bay Aquarium Seafood Watch program. However, a 2008 document submitted to the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) reported significant declines in toothfish populations of McMurdo Sound coinciding with the development of the industrial toothfishing industry since 1996, and other reports have noted
11988-523: Was later named the Ross Ice Shelf . Mount Erebus and Mount Terror are named after two ships from his expedition: HMS Erebus and HMS Terror . The Imperial Trans-Antarctic Expedition of 1914, led by Ernest Shackleton , set out to cross the continent via the pole, but their ship, Endurance , was trapped and crushed by pack ice before they even landed. The expedition members survived after an epic journey on sledges over pack ice to Elephant Island . Then Shackleton and five others crossed
12099-418: Was no land connection between New Zealand and Tierra del Fuego . Turning south again, Cook crossed the Antarctic Circle for the third time at 109° 30′ W before his progress was once again blocked by ice four days later at 71° 10′ S by 106° 54′ W . This point, reached on 30 January 1774, was the farthest south attained in the 18th century. With a great detour to the east, almost to the coast of South America,
12210-561: Was separated by sea from any continuous southern continent. The visit to South Georgia by Anthony de la Roché in 1675 was the first-ever discovery of land south of the Antarctic Convergence , i.e. in the Southern Ocean/Antarctic. Soon after the voyage cartographers started to depict " Roché Island ", honouring the discoverer. James Cook was aware of la Roché's discovery when surveying and mapping
12321-523: Was then known, and reported the discovery "of an Antarctic continent west of the Balleny Islands " on 25 January 1840. That part of Antarctica was later named " Wilkes Land ", a name it maintains to this day. Explorer James Clark Ross passed through what is now known as the Ross Sea and discovered Ross Island (both of which were named for him) in 1841. He sailed along a huge wall of ice that
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