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Graham Land

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66°00′S 63°30′W  /  66.000°S 63.500°W  / -66.000; -63.500

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128-638: Graham Land is the portion of the Antarctic Peninsula that lies north of a line joining Cape Jeremy and Cape Agassiz . This description of Graham Land is consistent with the 1964 agreement between the British Antarctic Place-names Committee and the US Advisory Committee on Antarctic Names , in which the name "Antarctic Peninsula" was approved for the major peninsula of Antarctica , and

256-685: A conspiracy among climate scientists to make up global warming, and said Doran's study definitively proved there was no warming in Antarctica outside of the Peninsula. Relatively few scientists responded to the book at the time, but it was mentioned in a 2006 US Senate hearing in support of climate change denial . Peter Doran published a statement in The New York Times decrying the misinterpretation of his work. The British Antarctic Survey and NASA also issued statements affirming

384-569: A corresponding increase in precipitation in the Northern Hemisphere, and an eventual decline of fisheries in the Southern Ocean, which could lead to a potential collapse of some marine ecosystems . These effects are expected to occur over centuries, but there has been limited research to date and few specifics are currently known. Contrasting temperature trends across parts of Antarctica mean some locations, particularly at

512-434: A funneling effect, which channels the winds into the relatively narrow Drake Passage . Hope Bay , at 63°23′S 057°00′W  /  63.383°S 57.000°W  / -63.383; -57.000 , is near the northern extremity of the peninsula, Prime Head , at 63°13′S. Near the tip at Hope Bay is Sheppard Point . The part of the peninsula extending northeastwards from a line connecting Cape Kater to Cape Longing

640-492: A high albedo (reflectivity), adds to the albedo of the ice sheets' own bright, white surface. Antarctica's coldness means it is the only place on Earth where an atmospheric temperature inversion occurs every winter; elsewhere on Earth, the atmosphere is at its warmest near the surface and becomes cooler as elevation increases. During the Antarctic winter, the surface of central Antarctica becomes cooler than middle layers of

768-581: A maritime Antarctic climate, is the mildest part of the Antarctic Peninsula. Within this part of the Antarctic Peninsula, temperatures exceed 0 °C (32 °F) for 3 or 4 months during the summer, and rarely fall below −10 °C (14 °F) during the winter. Farther south along the west coast and the northeast coast of the peninsula, mean monthly temperatures exceed 0 °C (32 °F) for only one or two months of summer and average around −15 °C (5 °F) in winter. The east coast of

896-670: A marked increase in the number of research bases as Britain, Chile and Argentina competed to make claims over the same area. Meteorology and geology were the primary research subjects. Since the peninsula has the mildest climate in Antarctica, the highest concentration of research stations on the continent can be found there, or on the many nearby islands, and it is the part of Antarctica most often visited by tour vessels and yachts. Occupied bases include Base General Bernardo O'Higgins Riquelme , Bellingshausen Station , Carlini Base , Comandante Ferraz Antarctic Station , Palmer Station , Rothera Research Station , and San Martín Base . Today on

1024-510: A reduction in atmospheric CO 2 concentrations. Initially, during the Eocene, this climate cooling resulted in a decrease in diversity of the angiosperm-dominated vegetation that inhabited the northern Antarctic Peninsula. During the Oligocene, about 34–23  Ma , these woodlands were replaced by a mosaic of southern beech ( Nothofagus ) and conifer-dominated woodlands and tundra as

1152-480: A sea-level rise of 0.5 m (1 ft 8 in) – 0.9 m (2 ft 11 in) from the current level of warming, a small fraction of the 53.3 m (175 ft) contained in the full ice sheet. With global warming of around 3 °C (5.4 °F), vulnerable areas like Wilkes Basin and Aurora Basin may collapse over around 2,000 years, potentially adding up to 6.4 m (21 ft 0 in) to sea levels. The complete melting and disappearance of

1280-537: A similar risk; with no climate mitigation, 80% of populations are at risk of extinction by 2100. With Paris-Agreement temperature goals in place, that number may fall to 31% under the 2 °C (3.6 °F) goal, and to 19% under the 1.5 °C (2.7 °F) goal. A 27-year study of the largest colony of Magellanic penguins that was published in 2014 found extreme weather caused by climate change kills seven percent of penguin chicks in an average year, accounting for up to 50% of all chick deaths in some years. Since 1987,

1408-505: A string of bedrock islands; these are separated by deep channels whose bottoms lie at depths considerably below current sea level. They are joined by a grounded ice sheet. Tierra del Fuego , the southernmost tip of South America , is about 1,000 km (620 miles) away across the Drake Passage . The Antarctic Peninsula is 522,000 square kilometres (202,000 sq mi) in area and 80% ice-covered. The marine ecosystem around

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1536-438: Is 35 cm (14 in) or less with occasional rain. Along the east coast of the Antarctic Peninsula south of 63° S, precipitation ranges from 10 to 15 cm (3.9 to 5.9 in). In comparison, the subantarctic islands have precipitation of 100–200 cm (39–79 in) per year and the dry interior of Antarctica is a virtual desert with only 10 cm (3.9 in) precipitation per year. The climate in and around

1664-564: Is a cormorant which is native to many sub-Antarctic islands, the Antarctic Peninsula and southern South America. Also present are the Antarctic petrel , Antarctic shag , king penguin , macaroni penguin , and Arctic tern . Although this very remote part of the world has never been inhabited and is protected by the Antarctic Treaty System , which bans industrial development, waste disposal and nuclear testing, there

1792-531: Is a risk future acidification would threaten the eggs of pteropods , a type of zooplankton . Antarctic krill are a key species in the Antarctic food web ; they feed on phytoplankton, and are the main food for fish and penguins. Krill are likely to abandon the fastest-warming areas, such as the Weddell Sea , while icefish may find shelf waters around Antarctic islands unsuitable. The shifts or declines in krill and copepod numbers are known to prevent

1920-492: Is also warming faster than the average. It is also a highly important carbon sink . These properties are connected to the Southern Ocean overturning circulation (SOOC), one half of the global thermohaline circulation . It is important estimates on when global warming will reach 2 °C (3.6 °F) – inevitable in all scenarios where greenhouse gas emissions have not been significantly lowered – depend on

2048-635: Is an active volcano at the southern end of this rift zone. Notable fossil locations include the Late Jurassic to Early Cretaceous Fossil Bluff Group of Alexander Island , Early Cretaceous sediments in Byers Peninsula on Livingston Island , and the sediments on Seymour Island , which include the Cretaceous extinction . The peninsula is very mountainous, its highest peaks rising to about 2,800 m (9,200 ft). Notable peaks on

2176-681: Is called the Trinity Peninsula. Brown Bluff is a rare tuya and Sheppard Nunatak is found here also. The Airy , Seller , Fleming and Prospect Glaciers form the Forster Ice Piedmont along the west coast of the peninsula. Charlotte Bay , Hughes Bay and Marguerite Bay are all on the west coast as well. On the east coast is the Athene Glacier ; the Arctowski and Åkerlundh Nunataks are both just off

2304-697: Is evident in the Scotia Metamorphic Complex, which outcrops on Elephant Island , along with Clarence and Smith Islands of the South Shetland Islands . The Drake Passage opened about 30 Ma as Antarctica separated from South America. The South Shetland Island separated from Graham Land about 4 Ma as a volcanic rift formed within the Bransfield Strait . Three dormant submarine volcanoes along this rift include The Axe, Three Sisters, and Orca. Deception Island

2432-408: Is expected to add about 11 cm (5 in) to global sea level rise . Marine ice sheet instability may cause West Antarctica to contribute tens of centimeters more if it is triggered before 2100. With higher warming, instability would be much more likely, and could double global, 21st-century sea-level rise. The fresh, 1100-1500 billion tons (GT) per year of meltwater from the ice dilutes

2560-686: Is far more stable than the West Antarctic ice sheet. The loss of the entire East Antarctic ice sheet would require global warming of between 5 °C (9.0 °F) and 10 °C (18 °F), and a minimum of 10,000 years. Some of its parts, such as Totten Glacier and Wilkes Basin , are in vulnerable subglacial basins that lie below sea level. Estimates suggest the irreversible loss of those basins would begin once global warming reaches 3 °C (5.4 °F), although this loss may become irreversible at warming of between 2 °C (3.6 °F) and 6 °C (11 °F). After global warming reaches

2688-468: Is followed and global warming is limited to 2 °C (3.6 °F), the loss of ice in Antarctica will continue at the 2020 rate for the rest of the 21st century, but if a trajectory leading to 3 °C (5.4 °F) is followed, Antarctica ice loss will accelerate after 2060 and start adding 0.5 cm (0.20 in) per year to global sea levels by 2100. Sea levels will continue to rise long after 2100 but potentially at very different rates. According to

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2816-659: Is likely to completely melt unless temperatures are reduced by 2 °C (3.6 °F) below 2020 levels. The loss of this ice sheet would take between 2,000 and 13,000 years, although several centuries of high greenhouse emissions could shorten this time to 500 years. A sea-level rise of 3.3 m (10 ft 10 in) would occur if the ice sheet collapses, leaving ice caps on the mountains, and 4.3 m (14 ft 1 in) if those ice caps also melt. Isostatic rebound may contribute an additional 1 m (3 ft 3 in) to global sea levels over another 1,000 years. The far-stabler East Antarctic ice sheet may only cause

2944-569: Is much-less certain than for the majority of tipping points in the climate system . Such a collapse would be prolonged; one estimate says it would occur before 2300. As with the better-studied Atlantic meridional overturning circulation (AMOC), a major slowing or collapse of the SOOC would have substantial regional and global effects. Some likely effects include a decline in precipitation in Southern Hemisphere countries like Australia,

3072-452: Is particularly threatening to penguins. As early as 2008, it was estimated every Southern Ocean temperature increase of 0.26 °C (0.47 °F) reduces king penguin populations by nine percent. Under the worst-case warming scenario, king penguins will permanently lose at least two of their current eight breeding sites, and 70% of the species (1.1 million pairs) will have to relocate to avoid extinction. Emperor penguin populations may be at

3200-616: Is still a threat to these fragile ecosystems from increasing tourism, primarily on cruises across the Southern Ocean from the port of Ushuaia , Argentina . A rich record of fossil leaves, wood, pollen, and flowers demonstrates that flowering plants thrived in subtropical climates within the volcanic island arcs that occupied the Antarctic Peninsula region during the Cretaceous and very early Paleogene periods. The analysis of fossil leaves and flowers indicates that semitropical woodlands, which were composed of ancestors of plants that live in

3328-670: Is subject to thaw. The permafrost in Antarctica traps various compounds, including persistent organic pollutants (POPs) like polycyclic aromatic hydrocarbons , many of which are known carcinogens or can cause liver damage; and polychlorinated biphenyls such as hexachlorobenzene (HCB) and DDT , which are associated with decreased reproductive success and immunohematological disorders. Antarctic soils also contain heavy metals, including mercury , lead and cadmium , all of which can cause endocrine disruption , DNA damage, immunotoxicity and reproductive toxicity. These compounds are released when contaminated permafrost thaws; this can change

3456-521: Is the potential for warm water currents to enter between the seafloor and the base of the ice sheet once the sheet is no longer heavy enough to displace such flows. Marine ice-cliff instability may cause ice cliffs taller than 100 m (330 ft) to collapse under their own weight once they are no longer buttressed by ice shelves. This process has never been observed and it only occurs in some models. By 2100, these processes may increase sea-level rise caused by Antarctica to 41 cm (16 in) under

3584-434: Is to lower the global temperature to 1 °C (1.8 °F) below the pre-industrial level, to 2 °C (3.6 °F) below the temperature of 2020. Other researchers said a climate engineering intervention to stabilize the ice sheet's glaciers may delay its loss by centuries and give the environment more time to adapt. This is an uncertain proposal and would be one of the most-expensive projects ever attempted. Otherwise,

3712-612: The Antarctic Circle , is the most northerly part of Antarctica, it has the mildest climates within this continent. Its climate is therefore classified as a tundra , rather than an ice cap . Its temperatures are warmest in January, averaging 1 to 2 °C (34 to 36 °F), and coldest in June, averages from −15 to −20 °C (5 to −4 °F). Its west coast from the tip of the Antarctic Peninsula south to 68° S , which has

3840-512: The Antarctic hair grass ( Deschampsia antarctica ) and Antarctic pearlwort ( Colobanthus quitensis ) are found on the northern and western parts of the Antarctic Peninsula, including offshore islands, where the climate is relatively mild. Lagotellerie Island in Marguerite Bay is an example of this habitat. Xanthoria elegans and Caloplaca are visible crustose lichens seen on coastal rocks. Antarctic krill are found in

3968-659: The British Antarctic Territory ) and Chile (as part of the Chilean Antarctic Territory ). Graham Land is the closest part of Antarctica to South America. Thus it is the usual destination for small ships taking paying visitors on Antarctic trips from South America . (Larger ships are not allowed to disembark passengers.) Until the discoveries of the British Graham Land Expedition of 1934–1937, it

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4096-675: The Cretaceous to present times, and outcrops are found along the Gerlache Strait , the Lemaire Channel , Argentine Islands , and Adelaide Island . These rocks in western Graham Land include andesite lavas and granite from the magma , and indicate Graham Land was a continuation of the Andes . This line of volcanoes are associated with subduction of the Phoenix Plate . Metamorphism associated with this subduction

4224-675: The Gondwanaland supercontinent. Analysis of paleontologic, stratigraphic, and sedimentologic data acquired from the study of drill core and seismic acquired during the Shallow Drilling on the Antarctic Continental Shelf (SHALDRIL) and other projects and from fossil collections from and rock outcrops within Alexander, James Ross, King George, Seymour, and South Shetland Islands has yielded a record of

4352-727: The McMurdo Dry Valleys in East Antarctica had experienced cooling of 0.7 °C per decade, a local trend that was confirmed by subsequent research at McMurdo. Multiple journalists said these findings were "contradictory" to global warming, even though the paper noted the limited data and found warming over 42% of the continent. What became known as the Antarctic Cooling Controversy received further attention in 2004, when Michael Crichton wrote that novel State of Fear , which said

4480-537: The Northern Hemisphere , an eventual decline of fisheries in the Southern Ocean and a potential collapse of certain marine ecosystems . While many Antarctic species remain undiscovered, there are documented increases in Antarctic flora , and large fauna such as penguins are already having difficulty retaining suitable habitat. On ice-free land, permafrost thaws release greenhouse gases and formerly frozen pollution. The West Antarctic ice sheet

4608-594: The Pleistocene shows partial loss can occur at lower warming levels; Wilkes Basin is estimated to have lost enough ice to add 0.5 m (1 ft 8 in) to sea levels between 115,000 and 129,000 years ago during the Eemian , and about 0.9 m (2 ft 11 in) between 318,000 and 339,000 years ago during Marine Isotope Stage 9 . Antarctica has much less permafrost than the Arctic . Antarctic permafrost

4736-564: The Swedish Antarctic Expedition , one of the first expeditions to explore parts of Antarctica. They landed on the Antarctic Peninsula in February 1902, aboard the ship Antarctic , which sank not far from the peninsula. All crew were rescued by an Argentine ship. The British Graham Land expedition between 1934 and 1937 carried out aerial surveys using a de Havilland Fox Moth aircraft, and concluded that Graham Land

4864-494: The United Kingdom . None of these claims have international recognition and, under the Antarctic Treaty System , the respective countries do not attempt to enforce their claims. The British claim, however, is recognised by Australia , France , New Zealand , and Norway . Argentina has the most bases and personnel stationed on the peninsula. The most likely first sighting of the Antarctic Peninsula, and therefore also of

4992-628: The dinosaur genus Antarctopelta , which was the first dinosaur fossil to be found on Antarctica. Paleogene and Early Eocene marine sediments that outcrop on Seymour Island contain plant-rich horizons. The fossil plants are dominated by permineralized branches of conifers and compressions of angiosperm leaves, and are found within carbonate concretions. These Seymour Island region fossils date to about 51.5–49.5  Ma and are dominated by leaves, cone scales, and leafy branches of Araucarian conifers, very similar in all respects to living Araucaria araucana (monkey puzzle) from Chile. They suggest that

5120-408: The killer whale . The animals of Antarctica live on food they find in the sea—not on land—and include seabirds , seals and penguins . The seals include: leopard seal ( Hydrurga leptonyx ), Weddell seal ( Leptonychotes weddellii ), the huge southern elephant seal ( Mirounga leonina ), and crabeater seal ( Lobodon carcinophagus ). Penguin species found on the peninsula, especially near

5248-440: The paleontology , sedimentology , stratigraphy , structural geology , and volcanology of glacial and nonglacial deposits of the Antarctic Peninsula has allowed the reconstruction of the paleoclimatology and prehistoric ice sheet fluctuation of it for over the last 100 million years. This research shows the dramatic changes in climate, which have occurred within this region after it reached its approximate position within

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5376-493: The 2010s, a temporary reduction in ice-shelf melting in West Antarctica allowed for the partial recovery of Antarctic bottom water and the lower cell of the circulation. Greater melting and further decline of the circulation is expected in the future. As bottom water weakens while the flow of warmer, fresher waters strengthens near the surface, the surface waters become more buoyant, and less likely to sink and mix with

5504-409: The 20th century, with the only uncertainty being the magnitude. During 2012-2013, estimates based on WAIS Divide ice cores and revised temperature records from Byrd Station suggested a much-larger West-Antarctica warming of 2.4 °C (4.3 °F) since 1958, or around 0.46 °C (0.83 °F) per decade, although there has been uncertainty about it. In 2022, a study narrowed the warming of

5632-805: The Antarctic Circle during the Cretaceous Period. The Fossil Bluff Group , which outcrops within Alexander Island , provides a detailed record, which includes paleosols and fossil plants, of Middle Cretaceous ( Albian ) terrestrial climates. The sediments that form the Fossil Bluff Group accumulated within a volcanic island arc , which now forms the bedrock backbone of the Antarctic Peninsula, in prehistoric floodplains and deltas and offshore as submarine fans and other marine sediments. As reflected in

5760-541: The Antarctic Peninsula formed as the bedrock islands underlying it were overridden and joined by an ice sheet in the early Pliocene about 5.3–3.6  Ma . During the Quaternary period, the size of the West Antarctic Ice Sheet has fluctuated in response to glacial–interglacial cycles. During glacial epochs, this ice sheet was significantly thicker than it is currently and extended to the edge of

5888-404: The Antarctic Peninsula is changing dramatically in 2024. The most recent temperature recorded was 10°C, which is higher than the peninsula region's average and deviates from the patterns of typical temperatures. The peninsula is getting very much affected by these sudden climate changes. In past years, researchers have seen northwesterly winds over the peninsula, and it is proven that this is one of

6016-685: The Antarctic Peninsula northward of a line between Cape Jeremy and Cape Agassiz ; and Palmer Land the part southward of that line, which is roughly 69° S. Palmer Land is named for the United States seal hunter Nathaniel Palmer . The Chilean name for the feature, O'Higgins Land, is in honor of Bernardo O'Higgins , the Chilean patriot and Antarctic visionary. Most other Spanish-speaking countries call it la Península Antártica , though Argentina also officially refers to this as Tierra de San Martín ; as of 2018 Argentina has more bases and personnel in

6144-448: The Antarctic Peninsula south of 63° S is generally much colder, with mean temperatures exceeding 0 °C (32 °F) for at most one month of summer, and winter mean temperatures ranging from −5 to −25 °C (23 to −13 °F). The colder temperatures of the southeast, Weddell Sea side, of the Antarctic Peninsula are reflected in the persistence of ice shelves that cling to the eastern side. Precipitation varies greatly within

6272-544: The Antarctic Peninsula there are many abandoned scientific and military bases. Argentina's Esperanza Base was the birthplace of Emilio Marcos Palma , the first person to be born in Antarctica. The grounding of the Argentine ship the ARA Bahía Paraíso and subsequent 170,000 US gal (640,000 L; 140,000 imp gal) oil spill occurred near the Antarctic Peninsula in 1989. Antarctica

6400-610: The Antarctic Peninsula was overridden by an ice sheet, which has persisted without any interruption to this day, in the early Pliocene, about 5.3–3.6  Ma . Climate change in Antarctica Climate change caused by greenhouse gas emissions from human activities occurs everywhere on Earth, and while Antarctica is less vulnerable to it than any other continent, climate change in Antarctica has been observed. Since 1959, there has been an average temperature increase of >0.05 °C/decade since 1957 across

6528-473: The Antarctic Peninsula, where human activity is higher than elsewhere. Black carbon deposits near common tourist sites and research stations increase summer seasonal melting by between about 5 to 23 kg (11 to 51 lb) of snow per m . By 2100, net ice loss from Antarctica is expected to add about 11 cm (4.3 in) to global sea-level rise. Other processes may cause West Antarctica to contribute more to sea-level rise. Marine ice-sheet instability

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6656-423: The Antarctic Peninsula. From the tip of the Antarctic Peninsula to 68° S, precipitation averages 35–50 cm (14–20 in) per year. A good portion of this precipitation falls as rain during the summer, on two-thirds of the days of the year, and with little seasonal variation in amounts. Between about 68° S and 63° S on the west coast of the Antarctic Peninsula and along its northeast coast, precipitation

6784-701: The Central area of the West Antarctic Ice Sheet between 1959 and 2000 to 0.31 °C (0.56 °F) per decade, and conclusively attributed it to increases in greenhouse gas concentrations caused by human activity. Between 2000 and 2020, local changes in atmospheric circulation patterns like the Interdecadal Pacific Oscillation (IPO) and the Southern Annular Mode (SAM) slowed or partially reversed

6912-520: The Cretaceous thermal maximum the climate, both regionally and globally, appears to have cooled as seen in the Antarctic fossil wood record. Later, warm high-latitude climates returned to the Antarctic Peninsula region during the Paleocene and early Eocene as reflected in fossil plants. Abundant plant and marine fossils from Paleogene marine sediments that outcrop on Seymour Island indicate the presence of cool and moist, high-latitudes environment during

7040-585: The East Antarctic ice sheet would require at least 10,000 years and would only occur if global warming reaches 5 °C (9.0 °F) to 10 °C (18 °F). Antarctica is the coldest, driest continent on Earth, and has the highest average elevation. Antarctica's dryness means the air contains little water vapor and conducts heat poorly. The Southern Ocean surrounding the continent is far more effective at absorbing heat than any other ocean. The presence of extensive, year-around sea ice , which has

7168-579: The East Antarctica interior demonstrated clear warming over those two decades. In particular, the South Pole warmed by 0.61 ± 0.34 °C per decade between 1990 and 2020, which is three times the global average. The Antarctica-wide warming trend continued after 2000, and in February 2020, the continent recorded its highest temperature of 18.3 °C, which is one degree higher than the previous record of 17.5 °C in March 2015. Models predict under

7296-600: The Late Cretaceous ( Coniacian and Santonian -early Campanian ) strata of the Hidden Lake and Santa Maria formations, which outcrop within James Ross , Seymour , and adjacent islands, indicate that this emergent volcanic island arc enjoyed warm temperate or subtropical climates with adequate moisture for growth and without extended periods of below freezing winter temperatures. After the peak warmth of

7424-610: The United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctica . The Antarctic Peninsula is part of the larger peninsula of West Antarctica , protruding 1,300 km (810 miles) from a line between Cape Adams ( Weddell Sea ) and a point on the mainland south of the Eklund Islands . Beneath the ice sheet that covers it, the Antarctic Peninsula consists of

7552-504: The West Antarctic ice sheet would cause around 3.3 m (10 ft 10 in) of sea-level rise. This kind of collapse is now considered almost inevitable because it appears to have occurred during the Eemian period 125,000 years ago, when temperatures were similar to those in the early 21st century. The Amundsen Sea also appears to be warming at rates that, if continued, make the ice sheet's collapse inevitable. The only way to reverse ice loss from West Antarctica once triggered

7680-440: The West Antarctic ice sheet, which is much smaller than the East Antarctic ice sheet and is grounded deep below sea level, is considered highly vulnerable. The melting of all of the ice in West Antarctica would increase global sea-level rise to 4.3 m (14 ft 1 in). Mountain ice caps that are not in contact with water are less vulnerable than the majority of the ice sheet, which is located below sea level. The collapse of

7808-529: The West Antarctic, the ocean has warmed by 1 °C (1.8 °F) since 1955. The warming of the Southern Ocean around Antarctica has caused the weakening or collapse of ice shelves , which float just offshore of glaciers and stabilize them. Many coastal glaciers have been losing mass and retreating, causing net-annual ice loss across Antarctica, although the East Antarctic ice sheet continues to gain ice inland. By 2100, net ice loss from Antarctica

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7936-511: The adjacent parts of the prehistoric Antarctic Peninsula were covered by forests that grew in a cool and moist, high-latitude environment during the early Eocene. During the Cenozoic climatic cooling, the Antarctic Peninsula was the last region of Antarctica to have been fully glaciated according to current research. As a result, this region was probably the last refugium for plants and animals that had inhabited Antarctica after it separated from

8064-487: The atmosphere; this means greenhouse gases trap heat in the middle atmosphere, and reduce its flow toward the surface and toward space, rather than preventing the flow of heat from the lower atmosphere to the upper layers. This effect lasts until the end of the Antarctic winter. Early climate models predicted temperature trends over Antarctica would emerge more slowly and be more subtle than those elsewhere. There were fewer than twenty permanent weather stations across

8192-437: The changes in terrestrial vegetation that occurred within the Antarctic Peninsula over the course of the past 37 million years. This research found that vegetation within the Antarctic Peninsula changed in response to a progressive climatic cooling that started with the initiation of mountain glaciation in the latest Eocene, about 37–34  Ma . The cooling was contemporaneous with glaciation elsewhere in Antarctica and

8320-586: The chemistry of surface water. Bioaccumulation and biomagnification spread these compounds throughout the food web. Permafrost thaw also results in greenhouse gas emissions , though the limited volume of Antarctic permafrost relative to Arctic permafrost means Antarctic permafrost is not considered a significant cause of climate change. Nearly all of the species in Antarctic are marine; by 2015, 8,354 species had been discovered in Antarctica and taxonomically accepted; of these species, only 57 were not marine. Antarctica may have up to 17,000 species; while 90% of

8448-407: The climate continued to cool. By middle Miocene, 16–11.6  Ma , a tundra landscape completely replaced any remaining woodlands. At this time, woodlands became completely extirpated from the Antarctic Peninsula and all of Antarctica. A tundra landscape probably persisted until about 12.8  Ma when the transition from a temperate, alpine glaciation to a dynamic ice sheet occurred. Eventually,

8576-473: The climate continues to warm and as human activity on the continent increases. Tourism in Antarctica has significantly increased since 2020; 74,400 tourists arrived there in late 2019 and early 2020. The development of Antarctica for the purposes of industry, tourism, and an increase in research facilities may put pressure on the continent and threaten its status as largely untouched land. Regulated tourism in Antarctica brings about awareness, and encourages

8704-409: The climate optimum, a distinct climate cooling, which lasted until historic times, occurred. The Antarctic Peninsula is a part of the world that is experiencing extraordinary warming. Each decade for the last five, average temperatures in the Antarctic Peninsula have risen by 0.5 °C (0.90 °F). Ice mass loss on the peninsula occurred at a rate of 60 billion tons / year in 2006, with

8832-588: The coasts, lose mass while locations further inland continue to gain mass. These contrasting trends and the remoteness of the region make estimating an average trend difficult. In 2018, a systematic review of all previous studies and data by the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE) estimated an increase in the West Antarctic ice sheet from 53 ± 29 Gt (gigatonnes) in 1992 to 159 ± 26 Gt in

8960-468: The commonest plants are lichens , followed by mosses and ice algae . In the Antarctic Peninsula, green snow algae have a combined biomass of around 1,300 t (2,900,000 lb). As glaciers retreat, they expose areas that often become colonized by pioneer lichen species. The reduction in precipitation in East Antarctica had turned many green mosses from green to red or brown as they respond to this drought. Schistidium antarctici had declined, while

9088-410: The continent and only two in the continent's interior. Automatic weather stations were deployed relatively late, and their observational record was brief for much of the 20th century satellite temperature measurements began in 1981 and are typically limited to cloud-free conditions. Thus, datasets representing the entire continent only began to appear by the very end of the 20th century. The exception

9216-496: The continent, although it had been uneven. West Antarctica warmed by over 0.1 °C/decade from the 1950s to the 2000s, and the exposed Antarctic Peninsula has warmed by 3 °C (5.4 °F) since the mid-20th century. The colder, stabler East Antarctica had been experiencing cooling until the 2000s. Around Antarctica, the Southern Ocean has absorbed more oceanic heat than any other ocean, and has seen strong warming at depths below 2,000 m (6,600 ft). Around

9344-620: The continental shelves. During interglacial epochs, the West Antarctica Ice Sheet was thinner than during glacial epochs and its margins lay significantly inland of the continental margins. During the Last Glacial Maximum , about 20,000 to 18,000 years ago, the ice sheet covering the Antarctic Peninsula was significantly thicker than it is now. Except for a few isolated nunataks , the Antarctic Peninsula and its associated islands were completely buried by

9472-494: The control of oil discharge, appropriate sewage disposal, and the prevention of pollution by toxic liquids. Antarctic Specially Protected Areas (ASPA) and Antarctic Specially Managed Areas (ASMA) are designated by the Antarctic Treaty to protect flora and fauna. Both ASPAs and ASMAs restrict entry but to different extents, with ASPAs being the highest level of protection. Designation of ASPAs has decreased 84% since

9600-513: The critical threshold for the collapse of these subglacial basins, their loss will likely occur over around 2,000 years, although the loss may be as fast as 500 years or as slow as 10,000 years. The loss of all of this ice would add between 1.4 m (4 ft 7 in) and 6.4 m (21 ft 0 in) to sea levels, depending on the ice sheet model used. Isostatic rebound of the newly ice-free land would add between 8 cm (3.1 in) and 57 cm (1 ft 10 in). Evidence from

9728-648: The desiccation-tolerant species Bryum pseudotriquetrum and Ceratodon purpureus have increased. The Antarctic ozone hole has led to an increase in UV-B radiation, which also causes observed damage to plant cells and photosynthesis . The only vascular plants on continental Antarctica are Deschampsia antarctica and Colobanthus quitensis , which are found on the Antarctic Peninsula. Increased temperatures have boosted photosynthesis and allowed these species to increase their population and range. Other plant species are increasingly likely to spread to Antarctica as

9856-431: The disappearance of the West Antarctic ice sheet would take an estimated 2,000 years. The loss of West Antarctica ice would take at least 500 years and possibly as long as 13,000 years. Once the ice sheet is lost, the isostatic rebound of the land previously covered by the ice sheet would result in an additional 1 m (3 ft 3 in) of sea-level rise over the following 1,000 years. The East Antarctic ice sheet

9984-812: The diversity of Antarctic species would decline by nearly 17% and the suitable climate area would shrink by 50%. Penguins are the highest species in the Antarctic food web and are already being substantially affected by climate change. Numbers of Adélie penguins , chinstrap penguins , emperor penguin and king penguins have already been declining, while the number of gentoo penguins has increased. Gentoo penguins, which are ice intolerant and use mosses as nesting material, have been able to spread into previously inaccessible territories and substantially increase in number. The vulnerable penguin species can respond through acclimatization , adaptation , or range shift. Range shift through dispersal leads to colonization elsewhere but results in local extinction. Climate change

10112-474: The early Eocene. Detailed studies of the paleontology, sedimentology, and stratigraphy of glacial and nonglacial deposits within the Antarctic Peninsula and adjacent parts of the Weddell Sea and its Pacific continental shelf have found that it has become progressively glaciated as the climate of Antarctica dramatically and progressively cooled during the last 37 million years. This progressive cooling

10240-504: The east coast. A number of smaller peninsulas extend from the main Antarctic Peninsula, including Hollick-Kenyon Peninsula and Prehn Peninsula at the base of the Antarctic Peninsula. Also located here are the Scaife Mountains . The Eternity Range is found in the middle of the peninsula. Other geographical features include Avery Plateau , the twin towers of Una Peaks . Because the Antarctic Peninsula, which reaches north of

10368-558: The emergent parts of the volcanic island arc, the eroded roots of which now form the central part of the Antarctic Peninsula, were covered by either warm temperate or subtropical forests. These fossil plants are indicative of tropical and subtropical forest at high paleolatitudes during the Middle and Late Cretaceous, which grew in climates without extended periods of below freezing winter temperatures and with adequate moisture for growth. The Cretaceous strata of James Ross Island also yielded

10496-755: The final five years of the study. On the Antarctic Peninsula, the study estimated a loss of 20 ± 15 Gt per year with an increase in loss of roughly 15 Gt per year after 2000, a significant quantity of which was the loss of ice shelves. The review's overall estimate was that Antarctica lost 2,720 ± 1,390 gigatons of ice from 1992 to 2017, averaging 109 ± 56 Gt per year. This would amount to 7.6 mm (0.30 in) of sea-level rise. A 2021 analysis of data from four research satellite systems – Envisat , European Remote-Sensing Satellite , GRACE and GRACE-FO , and ICESat  – indicated an annual mass loss of about 12 Gt from 2012 to 2016 due to much-greater ice gain in East Antarctica than earlier estimated, which offset most of

10624-572: The greatest change occurring in the northern tip of the peninsula. Seven ice shelves along the Antarctic Peninsula have retreated or disintegrated in the last two decades. Research by the United States Geological Survey has revealed that every ice front on the southern half of the peninsula experienced a retreat between 1947 and 2009. According to a study by the British Antarctic Survey , glaciers on

10752-494: The ice sheet from the Pacific outer continental shelf and the continental margin within the Weddell Sea. Within the Weddell Sea, the transition from grounded ice to a floating ice shelf occurred about 10,000 years ago. The deglaciation of some locations within the Antarctic Peninsula continued until 4,000 to 3,000 years ago. Within the Antarctic Peninsula, an interglacial climatic optimum occurred about 3,000 to 5,000 years ago. After

10880-415: The ice sheet is melting nonstop. Because of issues concerning global climate change, the Antarctic Peninsula and adjacent parts of the Weddell Sea and its Pacific continental shelf have been the subject of intensive geologic, paleontologic, and paleoclimatic research by interdisciplinary and multinational groups over the last several decades. The combined study of the glaciology of its ice sheet and

11008-438: The ice sheet. In addition, the ice sheet extended past the present shoreline onto the Pacific outer continental shelf and completely filled the Weddell Sea up to the continental margin with grounded ice. The deglaciation of the Antarctic Peninsula largely occurred between 18,000 and 6,000 years ago as an interglacial climate was established in the region. It initially started about 18,000 to 14,000 years ago with retreat of

11136-447: The investment and public support needed to preserve Antarctica's distinctive environment. An unmitigated loss of ice on land and sea could greatly reduce its attractiveness. Policy can be used to increase climate-change resilience through the protection of ecosystems. Ships that operate in Antarctic waters adhere to the international Polar Code , which includes regulations and safety measures such as operational training and assessments,

11264-604: The land by pack ice . Separating the peninsula from nearby islands are the Antarctic Sound , Erebus and Terror Gulf , George VI Sound , Gerlache Strait and the Lemaire Channel . The Lemaire Channel is a popular destination for tourist cruise ships that visit Antarctica. Further to the west lies the Bellingshausen Sea and in the north is the Scotia Sea . The Antarctic Peninsula and Cape Horn create

11392-409: The losses from West Antarctica. The East Antarctic ice sheet can still gain mass despite warming because effects of climate change on the water cycle increase precipitation over its surface, which then freezes and helps to accrete more ice. Black carbon from incomplete fuel combustion is carried long distances by wind. If it reaches Antarctica, black carbon accumulates on snow and ice, reducing

11520-482: The low-emission scenario and by 57 cm (22 in) under the high-emission scenario. Some scientists have given greater estimates but all agree melting in Antarctica would have a greater impact and would be much more likely to occur under higher warming scenarios, where it may double the overall 21st-century sea-level rise to 2 m (7 ft) or more. According to one study, if the Paris Agreement

11648-493: The lower layers, increasing ocean stratification . One study says the strength of the circulation would halve by 2050 under the worst climate-change scenario, with greater losses occurring afterwards. Paleoclimate evidence shows the entire circulation has significantly weakened or completely collapsed in the past; preliminary research says such a collapse may become likely once global warming reaches between 1.7 °C (3.1 °F) and 3 °C (5.4 °F), but this estimate

11776-486: The most common on the Antarctic Peninsula are the chinstrap and gentoo, with the only breeding colony of emperor penguins in West Antarctica an isolated population on the Dion Islands , in Marguerite Bay on the west coast of the peninsula. Most emperor penguins breed in East Antarctica. Seabirds of the Southern Ocean and West Antarctica found on the peninsula include: southern fulmar ( Fulmarus glacialoides ),

11904-406: The most intense climate change scenario , known as RCP8.5 , Antarctic temperatures will rise by 4 °C (7.2 °F) on average by 2100; this rise will be accompanied by a 30% increase in precipitation and a 30% decrease in sea ice. RCPs were developed in the late 2000s, and early 2020s research considers RCP8.5 much less likely than the more-moderate scenarios like RCP 4.5, which lie in between

12032-627: The most-recent reports of the Intergovernmental Panel on Climate Change ( SROCC and the IPCC Sixth Assessment Report ), there will be a median rise of 16 cm (6.3 in) and maximum rise of 37 cm (15 in) under the low-emission scenario. The highest-emission scenario results in a median rise of 1.46 m (5 ft) with a minimum of 60 cm (2 ft) and a maximum of 2.89 m ( 9 + 1 ⁄ 2  ft). Over longer timescales,

12160-456: The names Graham Land and Palmer Land for the northern and southern portions, respectively. The line dividing them is roughly 69 degrees south. Graham Land is named after Sir James R. G. Graham , First Lord of the Admiralty at the time of John Biscoe 's exploration of the west side of Graham Land in 1832. It is claimed by Argentina (as part of Argentine Antarctica ), Britain (as part of

12288-842: The northern peninsula ( Trinity Peninsula ) Península Trinidad or Tierra de la Trinidad . Similarly, Chile calls the entire Antarctic Peninsula Tierra de O'Higgins (Land of O'Higgins). The interior of Graham Land is occupied by a series of plateaus, namely (north to south) Laclavère Plateau , Louis Philippe Plateau , Detroit Plateau , Herbert Plateau , Foster Plateau , Forbidden Plateau , Bruce Plateau , Avery Plateau and Hemimont Plateau . Antarctic Peninsula 69°30′S 65°00′W  /  69.500°S 65.000°W  / -69.500; -65.000 The Antarctic Peninsula , known as O'Higgins Land in Chile and Tierra de San Martín in Argentina, and originally as Graham Land in

12416-517: The number of breeding pairs in the colony has fallen by 24%. Chinstrap penguins are also in decline, mainly due to a corresponding decline of Antarctic krill. It is estimated while Adélie penguins will retain some habitat past 2099, one-third of colonies along the West Antarctic Peninsula ;– around 20% of the species – will be in decline by 2060. On the Antarctic continent, plants are mainly found in coastal areas;

12544-403: The ocean around Antarctica is deeper than 1,000 m (3,281 ft), only 30% of the benthic-sample locations were taken at that depth. On the Antarctic continental shelves , bethnic-zone biomass may increase due to oceanic warming, which is likely to be of most benefit to seaweed . Around 12% of the native benthic species may be outcompeted and go extinct. These estimates are preliminary;

12672-494: The peninsula are not only retreating but also increasing their flow rate as a result of increased buoyancy in the lower parts of the glaciers. Professor David Vaughan has described the disintegration of the Wilkins Ice Shelf as the latest evidence of rapid warming in the area. The Intergovernmental Panel on Climate Change has been unable to determine the greatest potential effect on sea level rise that glaciers in

12800-402: The peninsula include Deschanel Peak , Mounts Castro , Coman , Gilbert , Jackson , William , Owen , Scott , and Hope , which is the highest point at 3,239 m (10,627 ft), Mount William , Mount Owen and Mount Scott . These mountains are considered to be a continuation of the Andes of South America , with a submarine spine or ridge connecting the two. This is the basis for

12928-552: The peninsula is typical Antarctic tundra . The peninsula has a sharp elevation gradient, with glaciers flowing into the Larsen Ice Shelf , which experienced significant breakup in 2002. Other ice shelves on the peninsula include the George VI , Wilkins , Wordie and Bach Ice Shelves . The Filchner-Ronne Ice Shelf lies to the east of the peninsula. Islands along the peninsula are mostly ice-covered and connected to

13056-466: The peninsula than any other nation. Other portions of the peninsula are named by and after the various expeditions that discovered them, including the Bowman , Black , Danco , Davis , English , Fallières , Nordenskjöld , Loubet , and Wilkins Coasts . The first Antarctic research stations were established during World War II by a British military operation, Operation Tabarin . The 1950s saw

13184-401: The plant fossils, paleosols, and climate models, the climate was warm, humid, and seasonally dry. According to climate models, the summers were dry and winters were wet. The rivers were perennial and subject to intermittent flooding as the result of heavy rainfall. Warm high-latitude climates reached a peak during the mid-Late Cretaceous Cretaceous Thermal Maximum . Plant fossils found within

13312-479: The position advanced by Chile and Argentina for their territorial claims. The Scotia Arc is the island arc system that links the mountains of the Antarctic Peninsula to those of Tierra del Fuego . There are various volcanoes in the islands around the Antarctic Peninsula. This volcanism is related to extensional tectonics in Bransfield Rift to the west and Larsen Rift to the east. The landscape of

13440-404: The reasons for the peninsula constantly melting and snow sublimation in 2024. Researchers are observing similar situations in 2024. Melting events have been observed on the eastern and western sides of the Peninsula in February and March. All three are contributing to the melting of ice in several Antarctic Peninsula areas, such as Larsen C and B. Furthermore, data from NASA's research indicates that

13568-445: The recovery in numbers of baleen whale following the declines caused by historical whaling . Without a reversal in temperature increases, baleen whales are likely to be forced to adapt their migratory patterns or face local extinction. Many other marine species are expected to move into Antarctic waters as the oceans continue to warm, forcing native species to compete with them. Some research says at 3 °C (5.4 °F) of warming,

13696-475: The reflectivity and causing it to absorb more energy. This accelerates melting and can create an ice-albedo feedback loop in which meltwater itself absorbs more heat from sunlight. Due to its remoteness, Antarctica has the cleanest snow in the world, and some research says the effects of black carbon across West and East Antarctica is minimal with an albedo reduction of about 0.5% in one 47-year ice core . The highest concentrations of black carbon are found on

13824-516: The region may cause. The coasts of the peninsula have the mildest climate in Antarctica and moss and lichen -covered rocks are free of snow during the summer months, although the weather is still intensely cold and the growing season very short. The plant life today is mainly mosses, lichens and algae adapted to this harsh environment, with lichens preferring the wetter areas of the rocky landscape. The most common lichens are Usnea and Bryoria species. Antarctica's two flowering plant species,

13952-488: The saline Antarctic bottom water , weakening the lower cell of the Southern Ocean overturning circulation (SOOC). According to some research, a full collapse of the SOOC may occur a between 1.7 °C (3.1 °F) and 3 °C (5.4 °F) of global warming, although the full effects are expected to occur over multiple centuries; these include less precipitation in the Southern Hemisphere but more in

14080-465: 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 ). The imperial shag

14208-432: The seas surrounding the peninsula and the rest of the continent. The crabeater seal spends most of its life in the same waters feeding on krill. Bald notothen is a cryopelagic fish that lives in sub-zero water temperatures around the peninsula. Vocalizations of the sei whale can be heard emanating from the waters surrounding the Antarctic Peninsula. Whales include the Antarctic minke whale , dwarf minke whale , and

14336-399: The spread of moss, alterations in phytoplankton and zooplankton community composition as well as changes in krill recruitment, abundance and availability to predators. The Antarctic Peninsula is currently dotted with numerous research stations, and nations have made multiple claims of sovereignty . The peninsula is part of disputed and overlapping claims by Argentina , Chile , and

14464-511: The strength of climate science after the hearing. By 2009, researchers were able to combine historical weather-station data with satellite measurements to create consistent temperature records going back to 1957 that demonstrated warming of >0.05 °C/decade since 1957 across the continent, with cooling in East Antarctica offset by the average temperature increase of at least 0.176 ± 0.06 °C per decade in West Antarctica. Subsequent research confirmed clear warming over West Antarctica in

14592-439: The strength of the circulation more than any factor other than the overall emissions. The overturning circulation has two parts; the smaller upper cell, which is most-strongly affected by winds and precipitation, and the larger lower cell that is defined by the temperature and salinity of Antarctic bottom water . Since the 1970s, the upper cell has strengthened by 50-60% while the lower cell has weakened by 10-20%. Some of this

14720-465: The tip and surrounding islands, include the chinstrap penguin , emperor penguin , gentoo penguin and the Adélie penguin . Petermann Island is the world's southernmost colony of gentoo penguins. The exposed rocks on the island is one of many locations on the peninsula that provides a good habitat for rookeries . The penguins return each year and may reach populations of more than ten thousand. Of these

14848-938: The tropics today, thrived within this region during a global thermal maximum with summer temperatures that averaged 20 °C (68 °F). The oldest fossil plants come from the middle Cretaceous (Albian) Fossil Bluff Group, which outcrop along the edge of Alexander Island. These fossils reveal that at this time the forests consisted of large conifers , with mosses and ferns in the undergrowth. The paleosols, in which trees are rooted, have physical characteristics indicative of modern soils that form under seasonally dry climates with periodic high rainfall. Younger Cretaceous strata, which outcrop within James Ross, Seymour, and adjacent islands, contain fossil plants of Late Cretaceous angiosperms with leaf morphotypes that are similar to those of living families such as Sterculiaceae, Lauraceae, Winteraceae, Cunoniaceae, and Myrtaceae. They indicate that

14976-572: The vulnerabilities of most Antarctic species have yet to be assessed. Unlike the Arctic, there has been little change in marine primary production across the Southern Ocean in the available observations. Estimates say an increase in Southern Ocean primary production could occur after 2100; this increase would block many nutrients from travelling to other oceans, leading to decreased production elsewhere. Some microbial communities appear to have been negatively affected by ocean acidification and there

15104-596: The warming of West Antarctica , with the Antarctic Peninsula experiencing cooling from 2002. While a variability in those patterns is natural, ozone depletion had also led the SAM to be stronger than it had been in the past 600 years of observations. Studies predicted a reversal in the SAM once the ozone layer began to recover following the Montreal Protocol , starting from 2002, and these changes are consistent with their predictions. As these patterns reversed,

15232-596: The western continental shelf of the Antarctic Peninsula (WAP) has been subjected to rapid climate change . Over the past 50 years, the warm, moist maritime climate of the northern WAP has shifted south. This climatic change increasingly displaces the once dominant cold, dry continental Antarctic climate. This regional warming has caused multi-level responses in the marine ecosystem such as increased heat transport , decreased sea ice extent and duration, local declines in ice-dependent Adélie penguins , increase in ice-tolerant gentoo and chinstrap penguins, accelerated greening due to

15360-503: The whole Antarctic mainland, was on 27 January 1820 by an expedition of the Imperial Russian Navy led by Fabian Gottlieb von Bellingshausen . But the party did not recognize as the mainland what they thought was an icefield covered by small hillocks. Three days later, on 30 January 1820, Edward Bransfield and William Smith , with a British expedition, were the first to chart part of the Antarctic Peninsula. This area

15488-521: The worst-case scenario and the Paris Agreement goals. Between 1971 and 2018, over 90% of thermal energy from global heating entered the oceans. The Southern Ocean absorbs the most heat; after 2005, it accounted for between 67% and 98% of all heat entering the oceans. The temperature in the ocean's upper layer in West Antarctica has warmed by 1 °C (1.8 °F) since 1955, and the Antarctic Circumpolar Current (ACC)

15616-442: Was contemporaneous with a reduction in atmospheric CO 2 concentrations. During this climatic cooling, the Antarctic Peninsula was probably the last region of Antarctica to have been fully glaciated . Within the Antarctic Peninsula, mountain glaciation was initiated during the latest Eocene, about 37–34  Ma . The transition from temperate, alpine glaciation to a dynamic ice sheet occurred about 12.8  Ma . At this time,

15744-412: Was due to the natural cycle of Interdecadal Pacific Oscillation (IPO) but there is a clear effect of climate change, because it alters winds and precipitation through shifts in the Southern Annular Mode (SAM) pattern. Fresh meltwater from the erosion of the West Antarctic ice sheet dilutes the more-saline Antarctic bottom water, which flows at a rate of 1100-1500 billion tons (GT) per year. During

15872-469: Was generally supposed to be an archipelago rather than a peninsula. The mountains of Graham Land are the last range of the American Cordillera , the almost continuous sequence of mountain ranges forming the western "backbone" of North America, Central America, South America and the Antarctic Peninsula . Argentina calls the area Tierra de San Martín (Land of San Martin) and also calls

16000-594: Was later to be called Trinity Peninsula and is the extreme northeast portion of the peninsula. The next confirmed sighting was in 1832 by John Biscoe , a British explorer, who named the northern part of the Antarctic Peninsula as Graham Land . The first European to land on the continent is also disputed. A 19th-century seal hunter , John Davis , was almost certainly the first. But, sealers were secretive about their movements and their logbooks were deliberately unreliable, to protect any new sealing grounds from competition. Between 1901 and 1904, Otto Nordenskjöld led

16128-526: Was not an archipelago but a peninsula. Agreement on the name "Antarctic Peninsula" by the Advisory Committee on Antarctic Names and UK Antarctic Place-Names Committee in 1964 resolved a long-standing difference over the use of the United States' name "Palmer Peninsula" or the British name "Graham Land" for this geographic feature. This dispute was resolved by making Graham Land the part of

16256-814: Was once part of the Gondwana supercontinent . Outcrops from this time include Ordovician and Devonian granites and gneiss found in the Scar Inlet and Joerg Peninsula , while the Carboniferous - Triassic Trinity Peninsula Group are sedimentary rocks that outcrop in Hope Bay and Prince Gustav Channel . Ring of Fire volcanic rocks erupted in the Jurassic , with the breakup of Gondwana, and outcrop in eastern Graham Land as volcanic ash deposits. Volcanism along western Graham Land dates from

16384-501: Was the Antarctic Peninsula , where warming was pronounced and well-documented; it was eventually found to have warmed by 3 °C (5.4 °F) since the mid 20th century. Based on this limited data, several papers published in the early 2000s said there had been an overall cooling over continental Antarctica outside the Peninsula. A 2002 analysis led by Peter Doran received widespread media coverage after it also indicated stronger cooling than warming between 1966 and 2000, and found

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