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Wednesday, October 4, 2023

Geography of Greenland

From Wikipedia, the free encyclopedia
 
Greenland
Native name:
Kalaallit Nunaat
Grønland
Greenland
Outline map of Greenland with ice sheet depths. (Much of the area in green has permanent snow cover, but less than 10m (33ft) thick.)
Geography
LocationBetween the Arctic Ocean and the North Atlantic Ocean
Coordinates64°10′N 51°43′W
Area2,166,086 km2 (836,330 sq mi)
Area rank1st
Coastline44,087 km (27394.4 mi)
Highest elevation3,694 m (12119 ft)
Highest pointGunnbjørn
Administration
Province Greenland
Largest settlementNuuk (Godthåb) (pop. 17,984)
Demographics
Population56,732 (February 8, 2020)
Pop. density0.028/km2 (0.073/sq mi)
Ethnic groups

Greenland is located between the Arctic Ocean and the North Atlantic Ocean, northeast of Canada and northwest of Iceland. The territory comprises the island of Greenland—the largest island in the world—and more than a hundred other smaller islands (see alphabetic list). Greenland has a 1.2 kilometre (0.75 mi) long border with Canada on Hans Island. A sparse population is confined to small settlements along certain sectors of the coast. Greenland possesses the world's second-largest ice sheet.

Greenland sits atop the Greenland plate, a subplate of the North American plate. The Greenland craton is made up of some of the oldest rocks on the face of the earth. The Isua greenstone belt in southwestern Greenland contains the oldest known rocks on Earth, dated at 3.7–3.8 billion years old.

The vegetation is generally sparse, with the only patch of forested land being found in Nanortalik Municipality in the extreme south near Cape Farewell.

The climate is arctic to subarctic, with cool summers and cold winters. The terrain is mostly a flat but gradually sloping icecap that covers all land except for a narrow, mountainous, barren, rocky coast. The lowest elevation is sea level and the highest elevation is the summit of Gunnbjørn Fjeld, the highest point in the Arctic at 3,694 meters (12,119 ft). The northernmost point of the island of Greenland is Cape Morris Jesup, discovered by Admiral Robert Peary in 1900. Natural resources include zinc, lead, iron ore, coal, molybdenum, gold, platinum, uranium, hydropower and fish.

Area

Total area: 2,166,086 km2

Land area: 2,166,086 km2 (410,449 km2 ice-free, 1,755,637 km2 ice-covered)

Maritime claims:

Territorial sea: 3 nautical miles (5.6 km; 3.5 mi)

Exclusive fishing zone: 200 nautical miles (370.4 km; 230.2 mi)

Land use

Arable land: approximately 6%; some land is used to grow silage.
Permanent crops: Approximately 0%
Other: 100% (2012 est.)

The total population comprises around 56,000 inhabitants, of whom approximately 18,000 live in the capital, Nuuk.

Natural hazards

Continuous ice sheet covers 84% of the country; the rest is permafrost.

Environment – current issues

Protection of the Arctic environment, climate change, pollution of the food chain, excessive hunting of endangered species (walrus, polar bears, narwhal, beluga whale and several sea birds).

Climate

Greenland map of Köppen climate classification
Retreat of the Helheim Glacier, Greenland
Map of Greenland's rate of change in ice sheet height
Map of Greenland bedrock

Greenland's climate is a tundra climate on and near the coasts and an ice cap climate in inland areas. It typically has short, cool summers and long, moderately cold winters.

Due to Gulf Stream influences, Greenland's winter temperatures are very mild for its latitude. In Nuuk, the capital, average winter temperatures are only −9 °C (16 °F). In comparison, the average winter temperatures for Iqaluit, Nunavut, Canada, are around −27 °C (−17 °F). Conversely, summer temperatures are very low, with an average high around 10 °C (50 °F). This is too low to sustain trees, and the land is treeless tundra.

On the Greenland ice sheet, the temperature is far below freezing throughout the year, and record high temperatures have peaked only slightly above freezing. The record high temperature at Summit Camp is 2.2 °C (36.0 °F).

In the far south of Greenland, there is a very small forest in the Qinngua Valley, due to summer temperatures being barely high enough to sustain trees. There are mountains over 1,500 metres (4,900 ft) high surrounding the valley, which protect it from cold, fast winds travelling across the ice sheet. It is the only natural forest in Greenland, but is only 15 kilometres (9.3 mi) long.


Climate data for Nuuk
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °C (°F) 13.5
(56.3)
13.0
(55.4)
13.2
(55.8)
14.6
(58.3)
18.3
(64.9)
23.8
(74.8)
26.3
(79.3)
25.1
(77.2)
23.8
(74.8)
19.9
(67.8)
15.8
(60.4)
13.2
(55.8)
26.3
(79.3)
Average high °C (°F) −5.6
(21.9)
−6.3
(20.7)
−6.8
(19.8)
−1.4
(29.5)
3.4
(38.1)
7.7
(45.9)
10.2
(50.4)
10.4
(50.7)
6.3
(43.3)
1.8
(35.2)
−1.1
(30.0)
−3.4
(25.9)
1.3
(34.3)
Daily mean °C (°F) −8.2
(17.2)
−9.1
(15.6)
−9.2
(15.4)
−3.6
(25.5)
0.8
(33.4)
4.4
(39.9)
6.8
(44.2)
7.3
(45.1)
3.7
(38.7)
−0.3
(31.5)
−3.4
(25.9)
−5.8
(21.6)
−1.4
(29.5)
Average low °C (°F) −10.4
(13.3)
−11.5
(11.3)
−11.4
(11.5)
−5.7
(21.7)
−2.5
(27.5)
1.7
(35.1)
3.8
(38.8)
4.0
(39.2)
2.8
(37.0)
−2.1
(28.2)
−5.4
(22.3)
−8
(18)
−3.7
(25.3)
Record low °C (°F) −32.5
(−26.5)
−29.6
(−21.3)
−27.5
(−17.5)
−30.0
(−22.0)
−19.0
(−2.2)
−10.3
(13.5)
−6.6
(20.1)
−4.7
(23.5)
−8.2
(17.2)
−16.6
(2.1)
−24.4
(−11.9)
−25.2
(−13.4)
−32.5
(−26.5)
Average precipitation mm (inches) 54.7
(2.15)
51.1
(2.01)
49.1
(1.93)
45.6
(1.80)
56.5
(2.22)
60.6
(2.39)
81.3
(3.20)
89.1
(3.51)
90.2
(3.55)
66.5
(2.62)
75.2
(2.96)
62.0
(2.44)
781.6
(30.77)
Average precipitation days (≥ 0.1 mm) 13.8 12.7 15.1 13.2 13.0 10.5 12.5 12.5 14.1 13.5 14.3 14.4 159.6
Average snowy days 13.6 12.1 14.5 11.4 9.4 2.8 0.1 0.2 4.3 9.8 12.7 13.8 104.7
Average relative humidity (%) 78 79 81 81 84 84 87 87 83 78 76 77 81
Mean monthly sunshine hours 15.5 65.0 148.8 180.0 189.1 204.0 195.3 164.3 141.0 80.6 30.0 6.2 1,419.8
Mean daily sunshine hours 0.5 2.3 4.8 6.0 6.1 6.8 6.3 5.3 4.7 2.6 1.0 0.2 3.9
Source 1: Danish Meteorological Institute
Source 2: Meteo Climat (record highs and lows), Deutscher Wetterdienst (humidity 1961–1990, sun 1980–1990)

Climate change

The Greenland ice sheet is 3 kilometers (1.9 mi) thick and broad enough to blanket an area the size of Mexico. The ice is so massive that its weight presses the bedrock of Greenland below sea level and is so all-concealing that not until recently did scientists discover Greenland's Grand Canyon or the possibility that Greenland might actually be three islands.

If the ice melted, the interior bedrock below sea level would be covered by water. It is not clear whether this water would be at sea level or a lake above sea level. If it would be at sea level it could connect to the sea at Ilulissat Icefjord, in Baffin Bay and near Nordostrundingen, creating three large islands. But it is most likely that it would be a lake with one drain.

It is thought that before the last Ice Age, Greenland had mountainous edges and a lowland (and probably very dry) center which drained to the sea via one big river flowing out westwards, past where Disko Island is now.

There is concern about sea level rise caused by ice loss (melt and glaciers falling into the sea) on Greenland. Between 1997 and 2003 ice loss was 68–92 km3/a (16–22 cu mi/a), compared to about 60 km3/a (14 cu mi/a) for 1993/4-1998/9. Half of the increase was from higher summer melting, with the rest caused by the movements of some glaciers exceeding the speeds needed to balance upstream snow accumulation. A complete loss of ice on Greenland would cause a sea level rise of as much as 6.40 meters (21.0 ft).

Researchers at NASA's Jet Propulsion Laboratory and the University of Kansas reported in February 2006 that the glaciers are melting twice as fast as they were five years ago. By 2005, Greenland was beginning to lose more ice volume than anyone expected – an annual loss of up to 52 cubic miles or 217 cubic kilometres per year, according to more recent satellite gravity measurements released by JPL. The increased ice loss may be partially offset by increased snow accumulation due to increased precipitation.

Between 1991 and 2006, monitoring of the weather at one location (Swiss Camp) found that the average winter temperature had risen almost 10 °F (5.6 °C).

Recently, Greenland's three largest outlet glaciers have started moving faster, satellite data show. These are the Jakobshavn Isbræ at Ilulissat on the western edge of Greenland, and the Kangerdlugssuaq and Helheim glaciers on the eastern edge of Greenland. The two latter accelerated greatly during the years 2004–2005, but returned to pre-2004 velocities in 2006. The accelerating ice flow has been accompanied by a dramatic increase in seismic activity. In March 2006, researchers at Harvard University and the Lamont–Doherty Earth Observatory at Columbia University reported that the glaciers now generate swarms of earthquakes up to magnitude 5.0.

The retreat of Greenland's ice is revealing islands that were thought to be part of the mainland. In September 2005 Dennis Schmitt discovered an island 400 miles (644 km) north of the Arctic Circle in eastern Greenland which he named Uunartoq Qeqertaq, Inuit for "warming island".

Future projections

In the Arctic, temperatures are rising faster than anywhere else in the world. Greenland is losing 200 billion tonnes of ice per year. Research suggests that this could increase the sea levels' rise by 30 centimeters by the end of the century. These projections have the possibility of changing as satellite data only dates back to 40 years ago. This means that researchers must view old photographs of glaciers and compare them to ones taken today to determine the future of Greenland's ice.

Temperature extremes

Climate data for Greenland
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °C (°F) 15.3
(59.5)
16.0
(60.8)
16.0
(60.8)
19.1
(66.4)
24.8
(76.6)
30.1
(86.2)
26.3
(79.3)
25.2
(77.4)
24.9
(76.8)
19.3
(66.7)
21.6
(70.9)
15.9
(60.6)
30.1
(86.2)
Record low °C (°F) −66.1
(−87.0)
−63.3
(−81.9)
−64.8
(−84.6)
−57.3
(−71.1)
−49.0
(−56.2)
−37.5
(−35.5)
−33.0
(−27.4)
−39.2
(−38.6)
−46.0
(−50.8)
−55.4
(−67.7)
−60.0
(−76.0)
−69.6
(−93.3)
−69.6
(−93.3)
Source 1: Weather Extremes Greenland, retrieved 28 July 2020 (all record lows except for Jan, Mar, May, Dec)(Jan and Feb record highs), Meteo Climat (Mar-Dec highs)
Source 2: Georgi, Johannes (1935), Eismitte record low, PANGAEA - Data Publisher for Earth & Environmental Science, doi:10.1594/PANGAEA.604003, retrieved 28 July 2020 (March record low),

May record low at Summit, retrieved 28 July 2020 (May record low), WUnderground, retrieved 28 July 2020 (record low all time)

Highest temperatures

Month Temperature Date Location
January 15.3 °C (59.5 °F) 29 January 2003 Nuuk, Sermersooq
February 16.0 °C (60.8 °F) 20 February 2005 Nanortailak, Kujalleq
March 16.0 °C (60.8 °F) 31 March 1975 Narsarsuaq, Kujalleq
April 19.1 °C (66.4 °F) 26 April 2016 Narsarsuaq, Kujalleq
May 24.8 °C (76.6 °F) 29 May 2012 Narsarsuaq, Kujalleq
June 30.1 °C (86.2 °F) 23 June 1915 Ivittuut, Sermersooq
July 26.3 °C (79.3 °F) 6 July 2008 Nuuk, Sermersooq
August 25.2 °C (77.4 °F) 3 August 1899 Tasillaq, Sermersooq
September 24.9 °C (76.8 °F) 2 September 2010 Nuuk, Sermersooq
October 19.3 °C (66.7 °F) 5 October 2016 Tasillaq, Sermersooq
November 21.6 °C (70.9 °F) 21 November 2015 Tasillaq, Sermersooq
December 15.9 °C (60.6 °F) 21 December 2001 Narsarsuaq, Kujalleq

Lowest temperatures

Month Temperature Date Location
January −66.1 °C (−87.0 °F) 9 January 1954 North Ice, Northeast Greenland
February −63.3 °C (−81.9 °F) 21 February 2002 Summit Camp Station, Northeast Greenland
March −64.8 °C (−84.6 °F) 20 March 1931 Eismitte, Northeast Greenland
April −57.3 °C (−71.1 °F) 21 April 2011 Summit Camp Station, Northeast Greenland
May −49.0 °C (−56.2 °F) 9 May 2018 Summit Camp Station, Northeast Greenland
June −37.5 °C (−35.5 °F) 1 June 2011 Summit Camp Station, Northeast Greenland
July −33.0 °C (−27.4 °F) 4 July 2017 Summit Camp Station, Northeast Greenland
August −39.2 °C (−38.6 °F) 29 August 2004 Summit Camp Station, Northeast Greenland
September −46.0 °C (−50.8 °F) 24 September 2009 Summit Camp Station, Northeast Greenland
October −55.4 °C (−67.7 °F) 26 October 2018 Summit Camp Station, Northeast Greenland
November −60.0 °C (−76.0 °F) 26 November 2001 Summit Camp Station, Northeast Greenland
December −69.6 °C (−93.3 °F) 22 December 1991 Klinck Station, Northeast Greenland

Topography

The ice sheet covering Greenland varies significantly in elevation across the landmass, rising dramatically between the coastline at sea level and the East-Central interior, where elevations reach 3,200 meters (10,500 ft). The coastlines are rocky and predominantly barren with fjords. Numerous small islands spread from the Central to Southern coastlines.

Greenland's mountain ranges are partially or completely buried by ice. The highest mountains are in the Watkins Range, which runs along the eastern coast. Greenland's highest mountain is Gunnbjorn Fjeld with a height of 3,700 meters (12,139 ft).

Scientists discovered an asteroid impact crater in the northwestern region of Greenland, buried underneath the ice sheet. At a size larger than Washington, D.C., it is the first impact crater found beneath one of Earth's ice sheets.

Extreme points

This is a list of the extreme points of Greenland, the points that are farther north, south, east or west than any other location.

Territory of Greenland

Mainland Greenland

Towns

Greenland has 17 towns – settlements with more than 500 inhabitants. Nuuk is the largest town – and the capital – with roughly one third of the country's urban population. Sisimiut with approximately 5,500 inhabitants is the second largest town, while Ilulissat is number three with around 5,000 inhabitants.

History of exploration

Representation of a Lie group

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Representation_of_a_Lie_group...