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Lake Thun ( German : Thunersee ) is an Alpine lake in the Bernese Oberland in Switzerland named after the city of Thun , on its northern shore. At 48.3 km (18.6 sq mi) in surface area, it is the largest Swiss lake entirely within a single canton.

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117-531: The lake was created after the last glacial period . After the 10th century, it split from Lake Brienz , before which the two lakes were combined, as Wendelsee ("Lake Wendel"). The culminating point of the lake's drainage basin is the Finsteraarhorn at 4,274 metres (14,022 ft) above sea level. Lake Thun's approximate 2,500 square kilometres (970 sq mi) catchment area frequently causes local flooding after heavy rainfalls. This occurs because

234-660: A maritime border , to the west and southwest across Nares Strait and Baffin Bay, as well as a shared land border on Hans Island ; and Iceland, southeast of Greenland in the Atlantic Ocean. Greenland also contains the world's largest national park , and it is the largest constituent country by area in the world, and is the fourth largest country subdivision in the world , after Sakha Republic in Russia, Australia's state of Western Australia , and Russia's Krasnoyarsk Krai , and

351-476: A series of expeditions to Greenland and Arctic waterways to locate the lost eastern Norse settlement and assert Danish-Norwegian sovereignty over Greenland. The expeditions were mostly unsuccessful, partly due to leaders who lacked experience with the difficult Arctic ice and weather conditions, and partly because the expedition leaders were given instructions to search for the Eastern Settlement on

468-1325: A lesser extent in the Southern Hemisphere. They have different names, historically developed and depending on their geographic distributions: Fraser (in the Pacific Cordillera of North America), Pinedale (in the Central Rocky Mountains ), Wisconsinan or Wisconsin (in central North America), Devensian (in the British Isles), Midlandian (in Ireland), Würm (in the Alps ), Mérida (in Venezuela ), Weichselian or Vistulian (in Northern Europe and northern Central Europe), Valdai in Russia and Zyryanka in Siberia , Llanquihue in Chile , and Otira in New Zealand. The geochronological Late Pleistocene includes

585-486: A number lost their cultural ties to Greenland. While the policies "succeeded" in the sense of shifting Greenlanders from being primarily subsistence hunters into being urbanized wage earners, the Greenlandic elite began to reassert a Greenlandic cultural identity. A movement developed in favour of independence, reaching its peak in the 1970s. As a consequence of political complications in relation to Denmark's entry into

702-423: A number of governmental services and areas of competence. The Danish government retains control of citizenship, monetary policy, and foreign affairs, including defence. Most residents of Greenland are Inuit. The population is concentrated mainly on the southwest coast, and the rest of the island is sparsely populated. Three-quarters of Greenland is covered by the only permanent ice sheet outside Antarctica . With

819-693: A population of 56,583 (2022), Greenland is the least densely populated region in the world. Sixty-seven percent of its electricity production comes from renewable energy, mostly from hydropower . The early Norse settlers named the island Greenland . In the Icelandic sagas , the Norwegian Erik the Red was exiled from Iceland with his father, Thorvald, who had committed manslaughter. With his extended family and his thralls ( slaves or serfs ) , he set out in ships to explore an icy land known to lie to

936-527: A relatively mild climate, several degrees Celsius warmer than usual in the North Atlantic with trees and herbaceous plants growing and livestock being farmed. Barley was grown as a crop up to the 70th parallel. The ice cores show that Greenland has had dramatic temperature shifts many times in the past 100,000 years. Similarly the Icelandic Book of Settlements records famines during

1053-527: A result of melting ice, the land has continued to rise yearly in Scandinavia, mostly in northern Sweden and Finland, where the land is rising at a rate of as much as 8–9 mm per year, or 1 m in 100 years. This is important for archaeologists, since a site that was coastal in the Nordic Stone Age now is inland and can be dated by its relative distance from the present shore. The term Würm

1170-494: A result of the COVID-19 pandemic ; one source describes it as being the "biggest economic victim of the coronavirus" (the overall economy did not suffer too severely as of mid-2020, thanks to the fisheries "and a hefty subsidy from Copenhagen"). Greenland's goal for returning tourism is to develop it "right" and to "build a more sustainable tourism for the long run". Greenland is the world's largest non-continental island and

1287-464: A sense of self-reliance through self-government and independent communication with the outside world. Despite this change, in 1946 a commission including the highest Greenlandic council, the Landsrådene , recommended patience and no radical reform of the system. Two years later, the first step towards a change of government was initiated when a grand commission was established. A final report (G-50)

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1404-403: A separate people under international law . Denmark maintains control of foreign affairs and defence matters. Denmark upholds the annual block grant of 3.2 billion Danish kroner, but as Greenland begins to collect revenues of its natural resources, the grant will gradually be diminished. This is generally considered to be a step toward eventual full independence from Denmark. Greenlandic

1521-458: A single ice age given the continual presence of ice sheets near both poles. Glacials are somewhat better defined, as colder phases during which glaciers advance, separated by relatively warm interglacials . The end of the last glacial period, which was about 10,000 years ago, is often called the end of the ice age, although extensive year-round ice persists in Antarctica and Greenland . Over

1638-797: A still lesser extent, glaciers existed in Africa, for example in the High Atlas , the mountains of Morocco , the Mount Atakor massif in southern Algeria , and several mountains in Ethiopia . Just south of the equator, an ice cap of several hundred square kilometers was present on the east African mountains in the Kilimanjaro massif , Mount Kenya , and the Rwenzori Mountains , which still bear relic glaciers today. Glaciation of

1755-532: Is Nuuk . Greenland lies between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago . It is the world's largest island , and is the location of the northernmost point of land in the world – Kaffeklubben Island off the northern coast is the world's northernmost undisputed point of land , and Cape Morris Jesup on the mainland was thought to be so until

1872-560: Is 2,166,086 km (836,330 sq mi) (including other offshore minor islands), of which the Greenland ice sheet covers 1,755,637 km (677,855 sq mi) (81%) and has a volume of approximately 2,850,000 km (680,000 cu mi). The highest point on Greenland is Gunnbjørn Fjeld at 3,700 m (12,100 ft) of the Watkins Range ( East Greenland mountain range ). The majority of Greenland, however,

1989-736: Is a North American island autonomous territory of the Kingdom of Denmark . It is the larger of two autonomous territories within the Kingdom, the other being the Faroe Islands ; the citizens of both territories are full citizens of Denmark . As Greenland is one of the Overseas Countries and Territories of the European Union , citizens of Greenland are European Union citizens . The capital and largest city of Greenland

2106-605: Is derived from a river in the Alpine foreland, roughly marking the maximum glacier advance of this particular glacial period. The Alps were where the first systematic scientific research on ice ages was conducted by Louis Agassiz at the beginning of the 19th century. Here, the Würm glaciation of the LGP was intensively studied. Pollen analysis , the statistical analyses of microfossilized plant pollens found in geological deposits, chronicled

2223-461: Is less than 1,500 m (4,900 ft) in elevation. Below the ice there is a series of canyons, the biggest called Greenland’s Grand Canyon which was formed by flowing rivers of water from the repeated cycle of ice melting and new ice forming. Near the coast elevations rise suddenly and steeply. The ice flows generally to the coast from the centre of the island. A survey led by French scientist Paul-Emile Victor in 1951 concluded that, under

2340-782: Is low compared with other countries (over one million species have been described worldwide). The sea is rich in fish and invertebrates, especially in the milder West Greenland Current ; a large part of the Greenland fauna is associated with marine-based food chains, including large colonies of seabirds. The few native land mammals in Greenland include the polar bear , reindeer (introduced by Europeans), arctic fox , arctic hare , musk ox , collared lemming , ermine , and arctic wolf . The last four are found naturally only in East Greenland , having immigrated from Ellesmere Island . There are dozens of species of seals and whales along

2457-423: Is not part of any municipality, but it is the site of the world's largest national park, Northeast Greenland National Park . At least four scientific expedition stations and camps had been established on the ice sheet in the ice-covered central part of Greenland (indicated as pale blue in the adjacent map): Eismitte , North Ice , North GRIP Camp and The Raven Skiway. There is a year-round station Summit Camp on

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2574-603: Is ongoing. The glaciation and the current Quaternary Period both began with the formation of the Arctic ice cap . The Antarctic ice sheet began to form earlier, at about 34 Mya, in the mid- Cenozoic ( Eocene–Oligocene extinction event ), and the term Late Cenozoic Ice Age is used to include this early phase with the current glaciation. The previous ice age within the Quaternary is the Penultimate Glacial Period , which ended about 128,000 years ago,

2691-506: The Skrælings (Norse word for Inuit, meaning "wretches" ). Recent archeological studies somewhat challenge the general assumption that the Norse colonization had a dramatic negative environmental effect on the vegetation. Data support traces of a possible Norse soil amendment strategy. More recent evidence suggests that the Norse, who never numbered more than about 2,500, gradually abandoned

2808-522: The Atlantic meridional overturning circulation , or AMOC, by diluting key currents, slowing it down. Due to this meltwater input, the circulation may even collapse outright, with widespread detrimental effects, although research suggests this is only likely if highest possible warming is sustained for multiple centuries. Greenland ice sheet has a great volume of ~2,900,000 cubic kilometres (696,000 cu mi). This means that if it were all to melt,

2925-710: The European Economic Community (EEC) upon achieving self-rule, as it did not agree with the EEC's commercial fishing regulations and an EEC ban on seal skin products. Greenland voters approved a referendum on greater autonomy on 25 November 2008. According to one study, the 2008 vote created what "can be seen as a system between home rule and full independence". On 21 June 2009, Greenland gained self-rule with provisions for assuming responsibility for self-government of judicial affairs , policing, and natural resources . Also, Greenlanders were recognized as

3042-695: The Last glacial cycle , occurred from the end of the Last Interglacial to the beginning of the Holocene , c.  115,000  – c.  11,700 years ago, and thus corresponds to most of the timespan of the Late Pleistocene . The LGP is part of a larger sequence of glacial and interglacial periods known as the Quaternary glaciation which started around 2,588,000 years ago and

3159-607: The Lesotho Highlands and parts of the Drakensberg . The development of glaciers was likely aided in part due to shade provided by adjacent cliffs. Various moraines and former glacial niches have been identified in the eastern Lesotho Highlands a few kilometres west of the Great Escarpment , at altitudes greater than 3,000 m on south-facing slopes. Studies suggest that the annual average temperature in

3276-727: The Owen Stanley Range , and the Saruwaged Range . Mount Giluwe in the Central Cordillera had a "more or less continuous ice cap covering about 188 km and extending down to 3200-3500 m". In Western New Guinea , remnants of these glaciers are still preserved atop Puncak Jaya and Ngga Pilimsit . Small glaciers developed in a few favorable places in Southern Africa during the last glacial period. These small glaciers would have been located in

3393-720: The Sierra Nevada in northern California . In northern Eurasia, the Scandinavian ice sheet once again reached the northern parts of the British Isles , Germany , Poland , and Russia, extending as far east as the Taymyr Peninsula in western Siberia. The maximum extent of western Siberian glaciation was reached by about 18,000 to 17,000 BP, later than in Europe (22,000–18,000 BP). Northeastern Siberia

3510-494: The Skaergaard intrusion . Notable rock provinces ( metamorphic igneous rocks, ultramafics, and anorthosites) are found on the southwest coast at Qeqertarsuatsiaat. East of Nuuk, the banded iron ore region of Isukasia, over three billion years old, contains the world's oldest rocks, such as greenlandite (a rock composed predominantly of hornblende and hyperthene), formed 3.8 billion years ago, and nuummite. In southern Greenland,

3627-732: The Upper Mississippi River , which in turn was formed during an earlier glacial period. In its retreat, the Wisconsin episode glaciation left terminal moraines that form Long Island , Block Island , Cape Cod , Nomans Land , Martha's Vineyard , Nantucket , Sable Island , and the Oak Ridges Moraine in south-central Ontario, Canada. In Wisconsin itself, it left the Kettle Moraine . The drumlins and eskers formed at its melting edge are landmarks of

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3744-537: The Younger Dryas , began around 12,800 years ago and ended around 11,700 years ago, also marking the end of the LGP and the Pleistocene epoch. It was followed by the Holocene , the current geological epoch . The LGP is often colloquially referred to as the "last ice age", though the term ice age is not strictly defined, and on a longer geological perspective, the last few million years could be termed

3861-584: The grooves left by these glaciers can be easily observed. In southwestern Saskatchewan and southeastern Alberta, a suture zone between the Laurentide and Cordilleran ice sheets formed the Cypress Hills , which is the northernmost point in North America that remained south of the continental ice sheets. The Great Lakes are the result of glacial scour and pooling of meltwater at the rim of

3978-586: The isostatically depressed area, a temporary marine incursion that geologists dub the Yoldia Sea . Then, as postglacial isostatic rebound lifted the region about 9500 BP, the deepest basin of the Baltic became a freshwater lake, in palaeological contexts referred to as Ancylus Lake , which is identifiable in the freshwater fauna found in sediment cores. The lake was filled by glacial runoff, but as worldwide sea level continued rising, saltwater again breached

4095-430: The 13th century and later, and are not primary sources for the history of early Norse Greenland. Those accounts are closer to primary for more contemporaneous accounts of late Norse Greenland. Modern understanding therefore mostly depends on the physical data from archeological sites. Interpretation of ice-core and clam-shell data suggests that between AD 800 and 1300 the regions around the fjords of southern Greenland had

4212-563: The 1920s suggest that the condition of human bones from this period indicates that the Norse population was malnourished, possibly because of soil erosion resulting from the Norsemen's destruction of natural vegetation in the course of farming, turf-cutting, and wood-cutting. Malnutrition may also have resulted from widespread deaths from pandemic plague; the decline in temperatures during the Little Ice Age; and armed conflicts with

4329-411: The 1960s. Though a part of the continent of North America, Greenland has been politically and culturally associated with Europe (specifically Norway and Denmark, the colonial powers) for more than a millennium, beginning in 986. Greenland has been inhabited at intervals over at least the last 4,500 years by circumpolar peoples whose forebears migrated there from what is now Canada. Norsemen settled

4446-486: The 2021 event, rain fell at Greenland's highest point for the first time in recorded history: an event so unexpected that the research station at the summit had no rain gauges for the occasion. As with the ice losses elsewhere, the melting of Greenland contributes to sea level rise. Between 2012 and 2017, this melting had added an average of 0.68 mm per year, which was equivalent to 37% of sea level rise from land ice sources (excluding thermal expansion of water from

4563-778: The Alpine foreland . Local ice fields or small ice sheets could be found capping the highest massifs of the Pyrenees , the Carpathian Mountains , the Balkan Mountains , the Caucasus , and the mountains of Turkey and Iran . In the Himalayas and the Tibetan Plateau , there is evidence that glaciers advanced considerably, particularly between 47,000 and 27,000 BP, but the exact ages, as well as

4680-745: The Center for Arctic Gas Hydrate, Environment and Climate at the University of Tromsø , published a study in June 2017 describing over a hundred ocean sediment craters, some 3,000 m wide and up to 300 m deep, formed by explosive eruptions of methane from destabilized methane hydrates , following ice-sheet retreat during the LGP, around 12,000 years ago. These areas around the Barents Sea still seep methane today. The study hypothesized that existing bulges containing methane reservoirs could eventually have

4797-687: The Early Dorset culture emerged in western Greenland and the Independence II culture in northern Greenland. The Dorset culture was the first culture to extend throughout the Greenlandic coastal areas, in the west and the east. It lasted until the total onset of the Thule culture , in AD ;1500. The people of the Dorset culture lived mainly by hunting whales and reindeer . From 986,

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4914-496: The European Common Market in 1972, Denmark began to seek a different status for Greenland, resulting in the Home Rule Act of 1979. This gave Greenland limited autonomy with its own legislature taking control of some internal policies, while the Parliament of Denmark maintained full control of external policies, security, and natural resources. The law came into effect on 1 May 1979. The King of Denmark , Frederik X , remains Greenland's head of state . In 1985, Greenland left

5031-474: The Greenland climate was dry during the LGP, with precipitation reaching perhaps only 20% of today's value. The name Mérida glaciation is proposed to designate the alpine glaciation that affected the central Venezuelan Andes during the Late Pleistocene. Two main moraine levels have been recognized - one with an elevation of 2,600–2,700 m (8,500–8,900 ft), and another with an elevation of 3,000–3,500 m (9,800–11,500 ft). The snow line during

5148-447: The Greenland settlements over the 15th century as walrus ivory , the most valuable export from Greenland, decreased in price because of competition with other sources of higher-quality ivory, and that there was actually little evidence of starvation or difficulties. Other explanations of the disappearance of the Norse settlements have been proposed: The Thule people are the ancestors of the current Greenlandic population. No genes from

5265-614: The Illimaussaq alkaline complex consists of pegmatites such as nepheline, syenites (especially kakortokite or naujaite) and sodalite (sodalite-foya). In Ivittuut, where cryolite was formerly mined, there are fluoride -bearing pegmatites. To the north of Igaliku, there are the Gardar alkaline pegmatitic intrusions of augite syenite, gabbro, etc. To the west and southwest are Palaeozoic carbonatite complexes at Kangerlussuaq (Gardiner complex) and Safartoq, and basic and ultrabasic igneous rocks at Uiffaq on Disko Island, where there are masses of heavy native iron up to 25 t (28 short tons) in

5382-495: The Inuit. It is republished in The Norse Atlantic Sagas , by Gwyn Jones. Jones reports that there is also an account of perhaps the same incident, of more doubtful provenance, told by the Norse side. In 1500, King Manuel I of Portugal sent Gaspar Corte-Real to Greenland in search of a Northwest Passage to Asia which, according to the Treaty of Tordesillas , was part of Portugal's sphere of influence. In 1501, Corte-Real returned with his brother, Miguel Corte-Real . Finding

5499-570: The LGP as the Devensian . Irish geologists, geographers, and archaeologists refer to the Midlandian glaciation, as its effects in Ireland are largely visible in the Irish Midlands . The name Devensian is derived from the Latin Dēvenses , people living by the Dee ( Dēva in Latin), a river on the Welsh border near which deposits from the period are particularly well represented. The effects of this glaciation can be seen in many geological features of England, Wales, Scotland, and Northern Ireland . Its deposits have been found overlying material from

5616-484: The Norse. When it re-established contact with Greenland in the early 17th century, Denmark-Norway asserted its sovereignty over the island. In 1721 a joint mercantile and clerical expedition led by Dano-Norwegian missionary Hans Egede was sent to Greenland, not knowing whether a Norse civilization remained there. This expedition is part of the Dano-Norwegian colonization of the Americas . After 15 years in Greenland, Hans Egede left his son Paul Egede in charge of

5733-505: The North American Laurentide ice sheet. At the height of glaciation, the Bering land bridge potentially permitted migration of mammals, including people, to North America from Siberia . It radically altered the geography of North America north of the Ohio River . At the height of the Wisconsin episode glaciation, ice covered most of Canada, the Upper Midwest , and New England , as well as parts of Montana and Washington . On Kelleys Island in Lake Erie or in New York's Central Park ,

5850-402: The Paleo-Inuit have been found in the present population of Greenland. The Thule culture migrated eastward from what is now known as Alaska around 1000 AD, reaching Greenland around 1300. The Thule culture was the first to introduce to Greenland such technological innovations as dog sleds and toggling harpoons . There is an account of contact and conflict with the Norse population, as told by

5967-410: The Polish River Vistula or its German name Weichsel). Evidence suggests that the ice sheets were at their maximum size for only a short period, between 25,000 and 13,000 BP. Eight interstadials have been recognized in the Weichselian, including the Oerel, Glinde, Moershoofd, Hengelo, and Denekamp. Correlation with isotope stages is still in process. During the glacial maximum in Scandinavia, only

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6084-437: The Southern Hemisphere was less extensive. Ice sheets existed in the Andes ( Patagonian Ice Sheet ), where six glacier advances between 33,500 and 13,900 BP in the Chilean Andes have been reported. Antarctica was entirely glaciated, much like today, but unlike today the ice sheet left no uncovered area. In mainland Australia only a very small area in the vicinity of Mount Kosciuszko was glaciated, whereas in Tasmania glaciation

6201-441: The Thule culture, who entered from the north. Norse Greenlanders submitted to Norwegian rule in 1261 under the Kingdom of Norway . The Kingdom of Norway entered a personal union with Denmark in 1380, and from 1397 was a part of the Kalmar Union . The Norse settlements, such as Brattahlíð , thrived for centuries, before disappearing in the 15th century, perhaps at the onset of the Little Ice Age . Except some runic inscriptions,

6318-431: The United States developed a geopolitical interest in Greenland and in 1946 offered to buy the island from Denmark for $ 100,000,000; the Danish rejected the offer. In the 21st century, the United States remains interested in investing in the resource base of Greenland and in tapping hydrocarbons off the Greenlandic coast. In August 2019, the US again proposed to buy the country, prompting premier Kim Kielsen to issue

6435-452: The Wisconsin episode. It began about 30,000 years ago, reached its greatest advance 21,000 years ago, and ended about 10,000 years ago. In northwest Greenland, ice coverage attained a very early maximum in the LGP around 114,000. After this early maximum, ice coverage was similar to today until the end of the last glacial period. Towards the end, glaciers advanced once more before retreating to their present extent. According to ice core data,

6552-448: The atlas's editor, commented: In the last two or three decades, global warming has reduced the size of glaciers throughout the Arctic and earlier this year, news sources confirmed what climate scientists already knew: water, not rock, lay beneath this ice bridge on the east coast of Greenland. More islets are likely to appear as the sheet of frozen water covering the world's largest island continues to melt. Some controversy surrounds

6669-473: The basalts. The paleontology of East Greenland is specially rich, with some of the early tetrapods such as the Devonian Acanthostega and Ichthyostega , and unique triassic animals such as the phytosaur Mystriosuchus alleroq and the dinosaurs Issi saaneq and tracks. Greenland is home to two ecoregions: Kalaallit Nunaat high arctic tundra and Kalaallit Nunaat low arctic tundra . There are approximately 700 known species of insects in Greenland, which

6786-552: The continual increase in the ocean heat content ). By the end of the century, the melting of Greenland alone would add between ~ 6 cm ( 2 + 1 ⁄ 2  in) if the temperatures are kept below 2 °C (3.6 °F), to around 13 cm (5 in) if the most intense climate change scenario with ever-increasing greenhouse gas emissions is followed. Under this scenario, the worst case for Greenland melting could reach 33 cm (13 in) of sea level rise equivalent. The large quantities of fresh meltwater also affect

6903-418: The control of the Danish monarch. Norway occupied then-uninhabited eastern Greenland as Erik the Red's Land in July 1931, claiming that it constituted terra nullius . Norway and Denmark agreed to submit the matter in 1933 to the Permanent Court of International Justice , which decided against Norway. Greenland's connection to Denmark was severed on 9 April 1940, early in World War II , after Denmark

7020-400: The dramatic changes in the European environment during the Würm glaciation. During the height of Würm glaciation, c.  24,000  – c.  10,000  BP, most of western and central Europe and Eurasia was open steppe-tundra, while the Alps presented solid ice fields and montane glaciers. Scandinavia and much of Britain were under ice. During the Würm, the Rhône Glacier covered

7137-410: The east coast of Greenland just north of Cape Farewell , which is almost inaccessible due to southward drifting ice . The pilot on all three trips was English explorer James Hall . After the Norse settlements died off, Greenland came under the de facto control of various Inuit groups, but the Dano-Norwegian government never forgot or relinquished the claims to Greenland that it had inherited from

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7254-418: The existence of a new island was announced. Named " Uunartoq Qeqertaq " (English: Warming Island ), this island has always been present off the coast of Greenland, but was covered by a glacier. This glacier was discovered in 2002 to be shrinking rapidly, and by 2007 had completely melted away, leaving the exposed island. The island was named Place of the Year by the Oxford Atlas of the World in 2007. Ben Keene,

7371-484: The facilities. After the collapse of the Third Reich, Albert Speer briefly considered escaping in a small aeroplane to hide out in Greenland, but changed his mind and decided to surrender to the United States Armed Forces . Greenland had been a protected and very isolated society until 1940. The Danish government had maintained a strict monopoly of Greenlandic trade , allowing no more than small scale barter trading with British whalers. In wartime Greenland developed

7488-423: The formation of a single contiguous ice sheet on the Tibetan Plateau, is controversial. Other areas of the Northern Hemisphere did not bear extensive ice sheets, but local glaciers were widespread at high altitudes. Parts of Taiwan , for example, were repeatedly glaciated between 44,250 and 10,680 BP as well as the Japanese Alps . In both areas, maximum glacier advance occurred between 60,000 and 30,000 BP. To

7605-447: The global sea levels would increase by ~7.4 m (24 ft) from that alone. However, it also means that it will take at least 1,000 years for the ice sheet to disappear even with very high warming, and in around 10,000 years under lower warming which still crosses the threshold for the ice sheet's disappearance. This threshold likely lies for the global warming between 1.7 °C (3.1 °F) and 2.3 °C (4.1 °F). Reducing

7722-405: The history of the island, specifically over whether the island might have been revealed during a brief warm period in Greenland during the mid-20th century. Greenland ice sheet always loses some mass from ice calving at its coasts, but it used to gain more ice on average due to the accumulation of snowfall. Yet, Greenland has been warming starting from around 1900, and starting from 1980s,

7839-422: The ice sheet, Greenland is composed of three large islands. This is disputed, but if it is so, they would be separated by narrow straits, reaching the sea at Ilulissat Icefjord , at Greenland's Grand Canyon and south of Nordostrundingen . All towns and settlements of Greenland are situated along the ice-free coast, with the population being concentrated along the west coast. The northeastern part of Greenland

7956-402: The ice sheet, established in 1989. The radio station Jørgen Brønlund Fjord was, until 1950, the northernmost permanent outpost in the world. The extreme north of Greenland, Peary Land , is not covered by an ice sheet, because the air there is too dry to produce snow, which is essential in the production and maintenance of an ice sheet. If the Greenland ice sheet were to melt away completely,

8073-405: The largest in North America. The lowest temperature ever recorded in the Northern Hemisphere was recorded in Greenland, near the topographic summit of the Greenland Ice Sheet , on 22 December 1991, when the temperature reached −69.6 °C (−93.3 °F). In Nuuk, the average daily temperature varies over the seasons from −5.1 to 9.9 °C (22.8 to 49.8 °F). The total area of Greenland

8190-447: The last glacial advance was lowered approximately 1,200 m (3,900 ft) below the present snow line, which is 3,700 m (12,100 ft). The glaciated area in the Cordillera de Mérida was about 600 km (230 sq mi); this included these high areas, from southwest to northeast: Páramo de Tamá, Páramo Batallón, Páramo Los Conejos, Páramo Piedras Blancas, and Teta de Niquitao. Around 200 km (77 sq mi) of

8307-444: The last glacial maximum, the Patagonian ice sheet extended over the Andes from about 35°S to Tierra del Fuego at 55°S. The western part appears to have been very active, with wet basal conditions, while the eastern part was cold-based. Cryogenic features such as ice wedges , patterned ground , pingos , rock glaciers , palsas , soil cryoturbation , and solifluction deposits developed in unglaciated extra-Andean Patagonia during

8424-574: The last glaciation, but not all these reported features have been verified. The area west of Llanquihue Lake was ice-free during the last glacial maximum, and had sparsely distributed vegetation dominated by Nothofagus . Valdivian temperate rain forest was reduced to scattered remnants on the western side of the Andes. Greenland Greenland ( Greenlandic : Kalaallit Nunaat , pronounced [kalaːɬːit nʉnaːt] ; Danish : Grønland , pronounced [ˈkʁɶnˌlænˀ] )

8541-627: The late glacial (Weichselian) and the immediately preceding penultimate interglacial ( Eemian ) period. Canada was almost completely covered by ice, as was the northern part of the United States , both blanketed by the huge Laurentide Ice Sheet . Alaska remained mostly ice free due to arid climate conditions. Local glaciations existed in the Rocky Mountains and the Cordilleran ice sheet and as ice fields and ice caps in

8658-479: The losses became larger than the gains. After 1996, Greenland has not had a single year when it did not lose mass on average. In 2010s, Greenland ice sheet had been melting at its fastest rate over at least the past 12,000 years, and on track to exceed that later in the century. In 2012, 2019 and 2021, so-called "massive melting events" had occurred, when practically the entire surface of the ice sheet had been melting and no accumulation had been taking place. During

8775-454: The lower Connecticut River Valley . In the Sierra Nevada , three stages of glacial maxima, sometimes incorrectly called ice ages , were separated by warmer periods. These glacial maxima are called, from oldest to youngest, Tahoe, Tenaya, and Tioga. The Tahoe reached its maximum extent perhaps about 70,000 years ago. Little is known about the Tenaya. The Tioga was the least severe and last of

8892-448: The main Wisconsin glacial advance. The upper level probably represents the last glacial advance (Late Wisconsin). The Llanquihue glaciation takes its name from Llanquihue Lake in southern Chile , which is a fan-shaped piedmont glacial lake. On the lake's western shores, large moraine systems occur, of which the innermost belong to the LGP. Llanquihue Lake's varves are a node point in southern Chile's varve geochronology . During

9009-484: The massive Missoula Floods . USGS geologists estimate that the cycle of flooding and reformation of the lake lasted an average of 55 years and that the floods occurred about 40 times over the 2,000-year period starting 15,000 years ago. Glacial lake outburst floods such as these are not uncommon today in Iceland and other places. The Wisconsin glacial episode was the last major advance of continental glaciers in

9126-469: The mission there and returned to Denmark, where he established a Greenland Seminary. This new colony was centred at Godthåb ("Good Hope") on the southwest coast. Gradually, Greenland was opened up to Danish merchants, but closed to those from other countries. When the union between the crowns of Denmark and Norway was dissolved in 1814, the Treaty of Kiel severed Norway's former colonies and left them under

9243-502: The mountains of Southern Africa was about 6 °C colder than at present, in line with temperature drops estimated for Tasmania and southern Patagonia during the same time. This resulted in an environment of relatively arid periglaciation without permafrost , but with deep seasonal freezing on south-facing slopes. Periglaciation in the eastern Drakensberg and Lesotho Highlands produced solifluction deposits and blockfields ; including blockstreams and stone garlands. Scientists from

9360-411: The northwest. After finding a habitable area and settling there, he named it Grœnland (translated as "Greenland"), supposedly in the hope that the pleasant name would attract settlers. The Saga of Erik the Red states: "In the summer, Erik left to settle in the country he had found, which he called Greenland, as he said people would be attracted there if it had a favorable name." The name of

9477-512: The only contemporary records or historiography that survives from the Norse settlements is of their contact with Iceland or Norway. Medieval Norwegian sagas and historical works mention Greenland's economy, the bishops of Gardar , and the collection of tithes. A chapter in the Konungs skuggsjá ( The King's Mirror ) describes Norse Greenland 's exports, imports, and grain cultivation. Icelandic saga accounts of life in Greenland were composed in

9594-592: The past few million years, the glacial-interglacial cycles have been "paced" by periodic variations in the Earth's orbit via Milankovitch cycles . The LGP has been intensively studied in North America, northern Eurasia, the Himalayas , and other formerly glaciated regions around the world. The glaciations that occurred during this glacial period covered many areas, mainly in the Northern Hemisphere and to

9711-543: The people in Greenland citizens of Denmark. In the 1979 Greenlandic home rule referendum , Denmark granted home rule to Greenland; in the 2008 Greenlandic self-government referendum , Greenlanders voted for the Self-Government Act, which transferred more power from the Danish government to the local Naalakkersuisut (Greenlandic government). Under this structure, Greenland gradually assumed responsibility for

9828-745: The preceding Ipswichian stage and lying beneath those from the following Holocene , which is the current stage. This is sometimes called the Flandrian interglacial in Britain. The latter part of the Devensian includes pollen zones I–IV, the Allerød oscillation and Bølling oscillation , and the Oldest Dryas , Older Dryas , and Younger Dryas cold periods. Alternative names include Weichsel glaciation or Vistulian glaciation (referring to

9945-493: The proglacial rivers' shifting and redepositing gravels. Beneath the surface, they had profound and lasting influence on geothermal heat and the patterns of deep groundwater flow. The Pinedale (central Rocky Mountains) or Fraser (Cordilleran ice sheet) glaciation was the last of the major glaciations to appear in the Rocky Mountains in the United States. The Pinedale lasted from around 30,000 to 10,000 years ago, and

10062-529: The receding ice. When the enormous mass of the continental ice sheet retreated, the Great Lakes began gradually moving south due to isostatic rebound of the north shore. Niagara Falls is also a product of the glaciation, as is the course of the Ohio River, which largely supplanted the prior Teays River . With the assistance of several very broad glacial lakes, it released floods through the gorge of

10179-568: The river Aare ( German : Aare ), which drains Lake Thun, has only limited capacity to handle the excess runoff. The lake is fed by water from Lake Brienz to the southeast, which is 6 metres (20 ft) higher than Lake Thun, and various streams in the Oberland, including the Kander . In 1835, passenger steamships began operating regularly on the lake. Ten passenger ships, operated by the local railway company BLS AG like Blümlisalp , serve

10296-399: The same fate. During the last glacial period, Antarctica was blanketed by a massive ice sheet, much as it is today. The ice covered all land areas and extended into the ocean onto the middle and outer continental shelf. Counterintuitively though, according to ice modeling done in 2002, ice over central East Antarctica was generally thinner than it is today. British geologists refer to

10413-577: The sea frozen, they headed south and arrived in Labrador and Newfoundland . Upon the brothers' return to Portugal, the cartographic information supplied by Corte-Real was incorporated into a new map of the world which was presented to Ercole I d'Este , Duke of Ferrara , by Alberto Cantino in 1502. The Cantino planisphere , made in Lisbon, accurately depicts the southern coastline of Greenland. In 1605–1607, King Christian IV of Denmark and Norway sent

10530-472: The sill about 8000 BP, forming a marine Littorina Sea , which was followed by another freshwater phase before the present brackish marine system was established. "At its present state of development, the marine life of the Baltic Sea is less than about 4000 years old", Drs. Thulin and Andrushaitis remarked when reviewing these sequences in 2003. Overlying ice had exerted pressure on the Earth's surface. As

10647-490: The statement, "Greenland is not for sale and cannot be sold, but Greenland is open for trade and cooperation with other countries—including the United States." In 1950, Denmark agreed to allow the US to regain the use of Thule Air Base ; it was greatly expanded between 1951 and 1953 as part of a unified NATO Cold War defence strategy. The local population of three nearby villages was moved more than 100 km (62 miles) away in

10764-480: The surrounding ice sheets. According to the sediment composition retrieved from deep-sea cores , even times of seasonally open waters must have occurred. Outside the main ice sheets, widespread glaciation occurred on the highest mountains of the Alpide belt . In contrast to the earlier glacial stages, the Würm glaciation was composed of smaller ice caps and mostly confined to valley glaciers, sending glacial lobes into

10881-451: The system of government changed: Governor Eske Brun ruled the island under a law of 1925 that allowed governors to take control under extreme circumstances; Governor Aksel Svane was transferred to the United States to lead the commission to supply Greenland. The Danish Sirius Patrol guarded the northeastern shores of Greenland in 1942 using dog sleds. They detected several German weather stations and alerted American troops, who destroyed

10998-737: The territory in the Greenlandic language is Kalaallit Nunaat ' land of the Kalaallit ' . The Kalaallit are the Greenlandic Inuit who inhabit the territory's western region. In prehistoric times, Greenland was home to several successive Paleo-Inuit cultures known primarily through archaeological finds. The earliest entry of the Paleo-Inuit into Greenland is thought to have occurred about 2500 BC. From about 2500 BC to 800 BC, southern and western Greenland

11115-787: The third largest area in North America after Canada and the United States. It is between latitudes 59° and 83°N , and longitudes 11° and 74°W . Greenland is bordered by the Arctic Ocean to the north, the Greenland Sea to the east, the North Atlantic Ocean to the southeast, the Davis Strait to the southwest, Baffin Bay to the west, the Nares Strait and Lincoln Sea to the northwest. The nearest countries to Greenland are Canada, with which it shares

11232-447: The total glaciated area was in the Sierra Nevada de Mérida , and of that amount, the largest concentration, 50 km (19 sq mi), was in the areas of Pico Bolívar , Pico Humboldt [4,942 m (16,214 ft)], and Pico Bonpland [4,983 m (16,348 ft)]. Radiocarbon dating indicates that the moraines are older than 10,000 BP, and probably older than 13,000 BP. The lower moraine level probably corresponds to

11349-596: The towns of Interlaken and Thun ; the Interlaken ship canal and Thun ship canal connect the lake to Interlaken West railway station and Thun railway station respectively. Following World War II and up until 1964, the Swiss Government disposed of unused munitions into Lake Thun. The quantity of munitions dumped is reported to be from 3,000 to more than 9,020 tons. Last glacial period The Last Glacial Period ( LGP ), also known as

11466-427: The turn of the 14th century—as much as 6 to 8 °C (11 to 14 °F) lower than modern summer temperatures. The study also found that the lowest winter temperatures of the last 2,000 years occurred in the late 14th century and early 15th century. The Eastern Settlement was probably abandoned in the early to mid-15th century, during this cold period . Theories drawn from archeological excavations at Herjolfsnes in

11583-492: The uninhabited southern part of Greenland beginning in the 10th century (having previously settled Iceland ), and the 13th century saw the arrival of Inuit . In the early 17th century, Dano-Norwegian explorers reached Greenland again. When Denmark and Norway separated in 1814, Greenland was transferred to the Danish crown, and was fully integrated in the Danish state in 1953 under the Constitution of Denmark , which made

11700-411: The warming back to 1.5 °C (2.7 °F) above preindustrial levels or lower (such as through large-scale carbon dioxide removal ) would arrest the losses, but still cause greater ultimate sea level rise than if the threshold had never been exceeded. Further, 1.5 °C (2.7 °F) itself appears to commit the ice sheet to 1.4 m ( 4 + 1 ⁄ 2  ft) of sea level rise. The island

11817-614: The west coast was settled by Icelanders and Norwegians , through a contingent of 14 boats led by Erik the Red. They formed three settlements—the Eastern Settlement , the Western Settlement , and the Middle Settlement —on fjords near the southwestern tip of the island. They shared the island with the late Dorset culture inhabitants, who occupied the northern and western parts, and later with those of

11934-604: The western parts of Jutland were ice-free, and a large part of what is today the North Sea was dry land connecting Jutland with Britain (see Doggerland ). The Baltic Sea , with its unique brackish water , is a result of meltwater from the Weichsel glaciation combining with saltwater from the North Sea when the straits between Sweden and Denmark opened. Initially, when the ice began melting about 10,300 BP, seawater filled

12051-728: The whole western Swiss plateau, reaching today's regions of Solothurn and Aargau. In the region of Bern, it merged with the Aar glacier. The Rhine Glacier is currently the subject of the most detailed studies. Glaciers of the Reuss and the Limmat advanced sometimes as far as the Jura. Montane and piedmont glaciers formed the land by grinding away virtually all traces of the older Günz and Mindel glaciation, by depositing base moraines and terminal moraines of different retraction phases and loess deposits, and by

12168-468: The winter. The United States tried to construct a subterranean network of secret nuclear missile launch sites in the Greenlandic ice cap, named Project Iceworm . According to documents declassified in 1996, this project was managed from Camp Century from 1960 to 1966 before abandonment as unworkable. The missiles were never fielded, and necessary consent from the Danish Government to do so

12285-490: The winters, in which "the old and helpless were killed and thrown over cliffs". These Norse settlements vanished during the 14th and early 15th centuries. The demise of the Western Settlement coincides with a decrease in summer and winter temperatures. A study of North Atlantic seasonal temperature variability during the Little Ice Age showed a significant decrease in maximum summer temperatures beginning about

12402-403: The world's sea level would rise by more than 7 m (23 ft). In 2003, a small island, 35 m × 15 m (115 ft × 49 ft) in length and width, was discovered by arctic explorer Dennis Schmitt and his team at the coordinates of 83-42 . Whether this island is permanent is not yet confirmed. If it is, it is the northernmost permanent known land on Earth. In 2007,

12519-464: Was at its greatest extent between 23,500 and 21,000 years ago. This glaciation was somewhat distinct from the main Wisconsin glaciation, as it was only loosely related to the giant ice sheets and was instead composed of mountain glaciers, merging into the Cordilleran ice sheet. The Cordilleran ice sheet produced features such as glacial Lake Missoula , which broke free from its ice dam, causing

12636-451: Was declared the sole official language of Greenland at the historic ceremony. Tourism increased significantly between 2015 and 2019, with the number of visitors increasing from 77,000 per year to 105,000. One source estimated that in 2019 the revenue from this aspect of the economy was about 450 million kroner (US$ 67 million). Like many aspects of the economy, this slowed dramatically in 2020 and into 2021, due to restrictions required as

12753-410: Was extended to Greenlanders. Danish policies toward Greenland consisted of a strategy of cultural assimilation — or de-Greenlandification. During this period, the Danish government promoted the exclusive use of the Danish language in official matters, and required Greenlanders to go to Denmark for their post-secondary education. Many Greenlandic children grew up in boarding schools in southern Denmark, and

12870-589: Was inhabited by the Saqqaq culture . Most finds of remains from that period have been around Disko Bay , including the site of Saqqaq, for which the culture is named. From 2400 BC to 1300 BC, the Independence I culture existed in northern Greenland. It was a part of the Arctic small-tool tradition . Towns, including Deltaterrasserne , appeared. About 800 BC, the Saqqaq culture disappeared and

12987-658: Was more severe than the Last Glacial Period in some areas such as Britain, but less severe in others. The last glacial period saw alternating episodes of glacier advance and retreat with the Last Glacial Maximum occurring between 26,000 and 20,000 years ago. While the general pattern of cooling and glacier advance around the globe was similar, local differences make it difficult to compare the details from continent to continent (see picture of ice core data below for differences). The most recent cooling,

13104-468: Was more widespread. An ice sheet formed in New Zealand, covering all of the Southern Alps, where at least three glacial advances can be distinguished. Local ice caps existed in the highest mountains of the island of New Guinea , where temperatures were 5 to 6 °C colder than at present. The main areas of Papua New Guinea where glaciers developed during the LGP were the Central Cordillera ,

13221-429: Was never sought. The Danish government did not become aware of the programme's mission until 1997, when they discovered it while looking, in the declassified documents, for records related to the crash of a nuclear equipped B-52  bomber at Thule in 1968. With the 1953 Danish constitution, Greenland's colonial status ended as the island was incorporated into the Danish realm as an amt (county). Danish citizenship

13338-512: Was not covered by a continental-scale ice sheet. Instead, large, but restricted, icefield complexes covered mountain ranges within northeast Siberia, including the Kamchatka-Koryak Mountains. The Arctic Ocean between the huge ice sheets of America and Eurasia was not frozen throughout, but like today, probably was covered only by relatively shallow ice, subject to seasonal changes and riddled with icebergs calving from

13455-705: Was occupied by Nazi Germany . On 8 April 1941, the United States occupied Greenland to defend it against a possible invasion by Germany. The United States' occupation of Greenland continued until 1945. Greenland was able to buy goods from the United States and Canada by selling cryolite from the mine at Ivittuut . In World War II , the United States military used Bluie as a code name for Greenland, where they kept several bases named "Bluie (East or West) (sequential numeral)". The major air bases were Bluie West-1 at Narsarsuaq and Bluie West-8 at Søndre Strømfjord (Kangerlussuaq), both of which are still used as Greenland's major international airports. During this war,

13572-666: Was part of the very ancient Precambrian continent of Laurentia , the eastern core of which forms the Greenland Shield, while the less exposed coastal strips become a plateau. On these ice-free coastal strips are sediments formed in the Precambrian , overprinted by metamorphism and now formed by glaciers, which continue into the Cenozoic and Mesozoic in parts of the island. In the east and west of Greenland there are remnants of flood basalts and igneous intrusions, such as

13689-604: Was presented in 1950, which recommended the introduction of a modern welfare state with Denmark's development as sponsor and model. In 1953, Greenland was made an equal part of the Danish Kingdom. Home rule was granted in 1979. In 1867, United States Secretary of State William H. Seward worked with former senator Robert J. Walker to explore the possibility of buying Greenland and, perhaps, Iceland . Opposition in Congress ended this project. Following World War II,

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