121-534: Isavia ohf. is the national airport and air navigation service provider of Iceland . The company operates all public airports and air navigation services in a vast area in the north-eastern Atlantic. The company headquarters is at Reykjavík Airport in Reykjavík . The enterprise was founded in 1945 as the Icelandic Civil Aviation Administration (Flugmálastjórn Íslands). With the creation of
242-424: A cirque landform (alternatively known as a corrie or as a cwm ) – a typically armchair-shaped geological feature (such as a depression between mountains enclosed by arêtes ) – which collects and compresses through gravity the snow that falls into it. This snow accumulates and the weight of the snow falling above compacts it, forming névé (granular snow). Further crushing of the individual snowflakes and squeezing
363-557: A longhouse in Stöðvarfjörður that may date to as early as 800. Swedish Viking explorer Garðar Svavarsson was the first to circumnavigate Iceland in 870 and establish that it was an island. He stayed during the winter and built a house in Húsavík . Garðar departed the following summer, but one of his men, Náttfari , decided to stay behind with two slaves. Náttfari settled in what is now known as Náttfaravík, and he and his slaves became
484-464: A shield volcano with a magma chamber underneath). Several classifications of the systems exist, for example there is one of 30 systems, and one of 34 systems, with the later currently being used in Iceland itself. The climate of Iceland's coast is subarctic . The warm North Atlantic Current ensures generally higher annual temperatures than in most places of similar latitude in the world. Regions in
605-528: A summit in Reykjavík in 1986 between United States President Ronald Reagan and Soviet Premier Mikhail Gorbachev , during which they took significant steps towards nuclear disarmament . A few years later, Iceland became the first country to recognise the independence of Estonia , Latvia , and Lithuania as they broke away from the USSR. Throughout the 1990s, the country expanded its international role and developed
726-444: A 32 percent increase in Iceland's gross national income between 2002 and 2007. In 2003–2007, following the privatisation of the banking sector under the government of Davíð Oddsson , Iceland moved towards having an economy based on international investment banking and financial services. It was quickly becoming one of the most prosperous countries in the world, but was hit hard by a major financial crisis . The crisis resulted in
847-634: A convicted child sex offender. Snap elections in October 2017 brought to power a new coalition consisting of the Independence Party, the Progressive Party, and the Left-Green Movement , headed by Katrín Jakobsdóttir . After the 2021 parliamentary election , the new government was, just like the previous government, a tri-party coalition of the Independence Party, the Progressive Party, and
968-636: A defence agreement was signed with the United States. American troops returned to Iceland as the Iceland Defence Force and remained throughout the Cold War . The US withdrew the last of its forces on 30 September 2006. Iceland prospered during the Second World War. The immediate post-war period was followed by substantial economic growth , driven by the industrialisation of the fishing industry and
1089-460: A famine that killed nearly a quarter of the island's population. In addition, the eruption caused dust clouds and haze to appear over most of Europe and parts of Asia and Africa for several months afterwards, and affected climates in other areas. Iceland has many geysers , including Geysir , from which the English word is derived, and the famous Strokkur , which erupts every 8–10 minutes. After
1210-589: A foreign policy orientated towards humanitarian and peacekeeping causes. To that end, Iceland provided aid and expertise to various NATO-led interventions in Bosnia , Kosovo , and Iraq . Iceland joined the European Economic Area in 1994, after which the economy was greatly diversified and liberalised. International economic relations increased further after 2001 when Iceland's newly deregulated banks began to raise great amounts of external debt , contributing to
1331-704: A fully sovereign and independent state in a personal union with Denmark. The Government of Iceland established an embassy in Copenhagen and requested that Denmark carry out on its behalf certain defence and foreign affairs matters, subject to consultation with the Althing. Danish embassies around the world displayed two coats of arms and two flags: those of the Kingdom of Denmark and those of the Kingdom of Iceland . Iceland's legal position became comparable to those of countries belonging to
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#17330855661121452-511: A glacier is usually assessed by determining the glacier mass balance or observing terminus behavior. Healthy glaciers have large accumulation zones, more than 60% of their area is snow-covered at the end of the melt season, and they have a terminus with a vigorous flow. Following the Little Ice Age 's end around 1850, glaciers around the Earth have retreated substantially . A slight cooling led to
1573-595: A glacier may flow into a body of water, it forms only on land and is distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water. On Earth, 99% of glacial ice is contained within vast ice sheets (also known as "continental glaciers") in the polar regions , but glaciers may be found in mountain ranges on every continent other than the Australian mainland, including Oceania's high-latitude oceanic island countries such as New Zealand . Between latitudes 35°N and 35°S, glaciers occur only in
1694-411: A glacier via moulins . Streams within or beneath a glacier flow in englacial or sub-glacial tunnels. These tunnels sometimes reemerge at the glacier's surface. Most of the important processes controlling glacial motion occur in the ice-bed contact—even though it is only a few meters thick. The bed's temperature, roughness and softness define basal shear stress, which in turn defines whether movement of
1815-408: A kilometer per year. Eventually, the ice will be surging fast enough that it begins to thin, as accumulation cannot keep up with the transport. This thinning will increase the conductive heat loss, slowing the glacier and causing freezing. This freezing will slow the glacier further, often until it is stationary, whence the cycle can begin again. The flow of water under the glacial surface can have
1936-404: A large effect on the motion of the glacier itself. Subglacial lakes contain significant amounts of water, which can move fast: cubic kilometers can be transported between lakes over the course of a couple of years. This motion is thought to occur in two main modes: pipe flow involves liquid water moving through pipe-like conduits, like a sub-glacial river; sheet flow involves motion of water in
2057-710: A latitude just south of the Arctic Circle . Its latitude and marine influence keep summers chilly, and most of its islands have a polar climate . According to the ancient manuscript Landnámabók , the settlement of Iceland began in 874 AD, when the Norwegian chieftain Ingólfr Arnarson became the island's first permanent settler. In the following centuries, Norwegians , and to a lesser extent other Scandinavians , immigrated to Iceland, bringing with them thralls (i.e., slaves or serfs) of Gaelic origin. The island
2178-466: A low- silica lava associated with effusive volcanism as has occurred also in Hawaii . Iceland, however, has a variety of volcanic types (composite and fissure), many producing more evolved lavas such as rhyolite and andesite . Iceland has hundreds of volcanoes with about 30 active volcanic systems. Surtsey , one of the youngest islands in the world, is part of Iceland. Named after Surtr , it rose above
2299-460: A lower heat conductance, meaning that the basal temperature is also likely to be higher. Bed temperature tends to vary in a cyclic fashion. A cool bed has a high strength, reducing the speed of the glacier. This increases the rate of accumulation, since newly fallen snow is not transported away. Consequently, the glacier thickens, with three consequences: firstly, the bed is better insulated, allowing greater retention of geothermal heat. Secondly,
2420-406: A phase of inactivity, Geysir started erupting again after a series of earthquakes in 2000 . Geysir has since grown quieter and does not erupt often. With the widespread availability of geothermal power and the harnessing of many rivers and waterfalls for hydroelectricity , most residents have access to inexpensive hot water, heating, and electricity. The island is composed primarily of basalt ,
2541-620: A popular holiday destination. In 2016, Prime Minister Sigmundur Davíð Gunnlaugsson resigned after being implicated in the Panama Papers scandal. Early elections in 2016 resulted in a right-wing coalition government of the Independence Party , the Reform Party and Bright Future . This government fell when Bright Future quit the coalition due to a scandal involving then-Prime Minister Bjarni Benediktsson 's father's letter of support for
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#17330855661122662-429: A republic in 1944, ending the remaining formal ties to Denmark. Although the Althing was suspended from 1799 to 1845, Iceland nevertheless has a claim to sustaining one of the world's longest-running parliaments. Until the 20th century, Iceland relied largely on subsistence fishing and agriculture. Industrialization of the fisheries and Marshall Plan aid after World War II brought prosperity, and Iceland became one of
2783-479: A society where subsistence depended almost entirely on agriculture. The Black Death swept Iceland twice, first in 1402–1404 and again in 1494–1495. The former outbreak killed 50% to 60% of the population, and the latter 30% to 50%. Around the middle of the 16th century, as part of the Protestant Reformation , King Christian III of Denmark began to impose Lutheranism on all his subjects. Jón Arason ,
2904-484: A thin layer. A switch between the two flow conditions may be associated with surging behavior. Indeed, the loss of sub-glacial water supply has been linked with the shut-down of ice movement in the Kamb ice stream. The subglacial motion of water is expressed in the surface topography of ice sheets, which slump down into vacated subglacial lakes. The speed of glacial displacement is partly determined by friction . Friction makes
3025-410: A tremendous impact as the iceberg strikes the water. Tidewater glaciers undergo centuries-long cycles of advance and retreat that are much less affected by climate change than other glaciers. Thermally, a temperate glacier is at a melting point throughout the year, from its surface to its base. The ice of a polar glacier is always below the freezing threshold from the surface to its base, although
3146-596: Is a Nordic island country between the North Atlantic and Arctic Oceans , on the Mid-Atlantic Ridge between North America and Europe . It is culturally and politically linked with Europe and is the region's westernmost and most sparsely populated country . Its capital and largest city is Reykjavík , which is home to about 36% of the country's roughly 380,000 residents (excluding nearby towns/suburbs which are separate municipalities). The official language of
3267-553: Is a sitka spruce planted in 1949 in Kirkjubæjarklaustur ; it was measured at 25.2 m (83 ft) in 2013. Algae such as Chondrus crispus , Phyllphora truncata and Phyllophora crispa and others have been recorded from Iceland. The only native land mammal when humans arrived was the Arctic fox , which came to the island at the end of the ice age, walking over the frozen sea. On rare occasions, bats have been carried to
3388-704: Is a Greenlandic private limited company owned by Isavia ANS. The air traffic controllers employed by Suluk provide, together with air traffic controllers from Isavia ANS, approach and tower services at Kangerlussuaq Airport. Isavia ANS and the Greenlandic airport company Mittarfeqarfiit have effective agreement for this service. Tern Systems has been developing software solutions for air traffic control for nearly 30 years, and solutions developed by Tern Systems are now in use across Europe, Asia, and Africa. Tern Systems aims to lead in safety and innovation in air traffic management in international airspace. The staff at Tern Systems
3509-456: Is above or at freezing at the interface and is able to slide at this contact. This contrast is thought to a large extent to govern the ability of a glacier to effectively erode its bed , as sliding ice promotes plucking at rock from the surface below. Glaciers which are partly cold-based and partly warm-based are known as polythermal . Glaciers form where the accumulation of snow and ice exceeds ablation . A glacier usually originates from
3630-407: Is affected by factors such as slope, ice thickness, snowfall, longitudinal confinement, basal temperature, meltwater production, and bed hardness. A few glaciers have periods of very rapid advancement called surges . These glaciers exhibit normal movement until suddenly they accelerate, then return to their previous movement state. These surges may be caused by the failure of the underlying bedrock,
3751-496: Is also where most settlements are situated. The island's interior, the Highlands of Iceland , is a cold and uninhabitable combination of sand, mountains, and lava fields . The major towns are the capital city of Reykjavík , along with its outlying towns of Kópavogur , Hafnarfjörður , and Garðabær , nearby Reykjanesbær where the international airport is located, and the town of Akureyri in northern Iceland. The island of Grímsey on
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3872-411: Is because these peaks are located near or in the hyperarid Atacama Desert . Glaciers erode terrain through two principal processes: plucking and abrasion . As glaciers flow over bedrock, they soften and lift blocks of rock into the ice. This process, called plucking, is caused by subglacial water that penetrates fractures in the bedrock and subsequently freezes and expands. This expansion causes
3993-406: Is by basal sliding, where meltwater forms between the ice and the bed itself. Whether a bed is hard or soft depends on the porosity and pore pressure; higher porosity decreases the sediment strength (thus increases the shear stress τ B ). Porosity may vary through a range of methods. Bed softness may vary in space or time, and changes dramatically from glacier to glacier. An important factor
4114-434: Is called glaciology . Glaciers are important components of the global cryosphere . Glaciers are categorized by their morphology, thermal characteristics, and behavior. Alpine glaciers form on the crests and slopes of mountains. A glacier that fills a valley is called a valley glacier , or alternatively, an alpine glacier or mountain glacier . A large body of glacial ice astride a mountain, mountain range, or volcano
4235-416: Is called rock flour and is made up of rock grains between 0.002 and 0.00625 mm in size. Abrasion leads to steeper valley walls and mountain slopes in alpine settings, which can cause avalanches and rock slides, which add even more material to the glacier. Glacial abrasion is commonly characterized by glacial striations . Glaciers produce these when they contain large boulders that carve long scratches in
4356-456: Is closer to continental Europe than to mainland North America, although it is closest to Greenland (290 kilometres; 155 nautical miles), an island of North America. Iceland is generally included in Europe for geographical, historical, political, cultural, linguistic and practical reasons. Geologically, the island includes parts of both continental plates. The closest bodies of land in Europe are
4477-580: Is higher, and the mountains above 5,000 m (16,400 ft) usually have permanent snow. Even at high latitudes, glacier formation is not inevitable. Areas of the Arctic , such as Banks Island , and the McMurdo Dry Valleys in Antarctica are considered polar deserts where glaciers cannot form because they receive little snowfall despite the bitter cold. Cold air, unlike warm air, is unable to transport much water vapor. Even during glacial periods of
4598-747: Is low compared with other countries (over one million species have been described worldwide). Iceland is essentially free of mosquitoes . Glacier A glacier ( US : / ˈ ɡ l eɪ ʃ ər / ; UK : / ˈ ɡ l æ s i ər , ˈ ɡ l eɪ s i ər / ) is a persistent body of dense ice that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries . It acquires distinguishing features, such as crevasses and seracs , as it slowly flows and deforms under stresses induced by its weight. As it moves, it abrades rock and debris from its substrate to create landforms such as cirques , moraines , or fjords . Although
4719-520: Is passionate about software development and committed to creating advanced technical solutions with the needs of their customers in mind. Tern Systems employs over 80 people and has its headquarters in Iceland, with offices in Hungary and Poland. Regional Airports manages all Icelandic scheduled airports, excluding KEF. Operations are based on a service agreement with the Ministry of Infrastructure, which defines
4840-552: Is responsible for implementing its own policies and strategies. These three subsidiaries are: Provides air navigation services for domestic and international flights in the North Atlantic airspace and offers specialized training for air traffic control, aeronautical communication, information services, and flight inspection in Iceland, Greenland, and the Faroe Islands. ANS owns two Subsidiaries; Suluk APS and Tern Systems. Suluk
4961-897: Is termed an ice cap or ice field . Ice caps have an area less than 50,000 km (19,000 sq mi) by definition. Glacial bodies larger than 50,000 km (19,000 sq mi) are called ice sheets or continental glaciers . Several kilometers deep, they obscure the underlying topography. Only nunataks protrude from their surfaces. The only extant ice sheets are the two that cover most of Antarctica and Greenland. They contain vast quantities of freshwater, enough that if both melted, global sea levels would rise by over 70 m (230 ft). Portions of an ice sheet or cap that extend into water are called ice shelves ; they tend to be thin with limited slopes and reduced velocities. Narrow, fast-moving sections of an ice sheet are called ice streams . In Antarctica, many ice streams drain into large ice shelves . Some drain directly into
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5082-413: Is the region where there is a net loss in glacier mass. The upper part of a glacier, where accumulation exceeds ablation, is called the accumulation zone . The equilibrium line separates the ablation zone and the accumulation zone; it is the contour where the amount of new snow gained by accumulation is equal to the amount of ice lost through ablation. In general, the accumulation zone accounts for 60–70% of
5203-513: Is the surface expression of the Iceland Plateau , a large igneous province forming as a result of volcanism from the Iceland hotspot and along the Mid-Atlantic Ridge , the latter of which runs right through it. This means that the island is highly geologically active with many volcanoes including Hekla , Eldgjá , Herðubreið , and Eldfell . The volcanic eruption of Laki in 1783–1784 caused
5324-402: Is the underlying geology; glacial speeds tend to differ more when they change bedrock than when the gradient changes. Further, bed roughness can also act to slow glacial motion. The roughness of the bed is a measure of how many boulders and obstacles protrude into the overlying ice. Ice flows around these obstacles by melting under the high pressure on their stoss side ; the resultant meltwater
5445-552: Is then forced into the cavity arising in their lee side , where it re-freezes. As well as affecting the sediment stress, fluid pressure (p w ) can affect the friction between the glacier and the bed. High fluid pressure provides a buoyancy force upwards on the glacier, reducing the friction at its base. The fluid pressure is compared to the ice overburden pressure, p i , given by ρgh. Under fast-flowing ice streams, these two pressures will be approximately equal, with an effective pressure (p i – p w ) of 30 kPa; i.e. all of
5566-903: The Andes , the Himalayas , the Rocky Mountains , the Caucasus , Scandinavian Mountains , and the Alps . Snezhnika glacier in Pirin Mountain, Bulgaria with a latitude of 41°46′09″ N is the southernmost glacial mass in Europe. Mainland Australia currently contains no glaciers, although a small glacier on Mount Kosciuszko was present in the last glacial period . In New Guinea, small, rapidly diminishing, glaciers are located on Puncak Jaya . Africa has glaciers on Mount Kilimanjaro in Tanzania, on Mount Kenya , and in
5687-456: The Boreal Kingdom . Plantlife consists mainly of grassland, which is regularly grazed by livestock. The most common tree native to Iceland is the northern birch ( Betula pubescens ), which formerly formed forests over much of Iceland, along with aspens ( Populus tremula ), rowans ( Sorbus aucuparia ), common junipers ( Juniperus communis ), and other smaller trees, mainly willows. When
5808-636: The Faroe and Crozet Islands were completely glaciated. The permanent snow cover necessary for glacier formation is affected by factors such as the degree of slope on the land, amount of snowfall and the winds. Glaciers can be found in all latitudes except from 20° to 27° north and south of the equator where the presence of the descending limb of the Hadley circulation lowers precipitation so much that with high insolation snow lines reach above 6,500 m (21,330 ft). Between 19˚N and 19˚S, however, precipitation
5929-583: The Faroe Islands (420 km; 225 nmi); Jan Mayen Island (570 km; 310 nmi); Shetland and the Outer Hebrides , both about 740 km (400 nmi); and the Scottish mainland and Orkney , both about 750 km (405 nmi). The nearest part of Continental Europe is mainland Norway, about 970 km (525 nmi) away, while mainland North America is 2,070 km (1,120 nmi) away, at
6050-750: The Himalayas , Andes , and a few high mountains in East Africa, Mexico, New Guinea and on Zard-Kuh in Iran. With more than 7,000 known glaciers, Pakistan has more glacial ice than any other country outside the polar regions. Glaciers cover about 10% of Earth's land surface. Continental glaciers cover nearly 13 million km (5 million sq mi) or about 98% of Antarctica 's 13.2 million km (5.1 million sq mi), with an average thickness of ice 2,100 m (7,000 ft). Greenland and Patagonia also have huge expanses of continental glaciers. The volume of glaciers, not including
6171-526: The Little Ice Age , and overgrazing by sheep imported by settlers caused a loss of critical topsoil due to erosion . Today, many farms have been abandoned. Three-quarters of Iceland's 100,000 square kilometres (39,000 sq mi) is affected by soil erosion; 18,000 km (6,900 sq mi) is affected to a degree serious enough to make the land useless. Only a few small birch stands now exist in isolated reserves. The Icelandic Forest Service and other forestry groups promote large-scale reforestation in
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#17330855661126292-524: The Mid-Atlantic Ridge , a ridge along which the oceanic crust spreads and forms new crust. This part of the mid-ocean ridge is located above a mantle plume, causing Iceland to be subaerial (above the surface of the sea). The ridge marks the boundary between the Eurasian and North American Plates , and Iceland was created by rifting and accretion through volcanism along the ridge. Many fjords punctuate Iceland's 4,970-km-long (3,088-mi) coastline, which
6413-551: The Quaternary , Manchuria , lowland Siberia , and central and northern Alaska , though extraordinarily cold, had such light snowfall that glaciers could not form. In addition to the dry, unglaciated polar regions, some mountains and volcanoes in Bolivia, Chile and Argentina are high (4,500 to 6,900 m or 14,800 to 22,600 ft) and cold, but the relative lack of precipitation prevents snow from accumulating into glaciers. This
6534-521: The Rwenzori Mountains . Oceanic islands with glaciers include Iceland, several of the islands off the coast of Norway including Svalbard and Jan Mayen to the far north, New Zealand and the subantarctic islands of Marion , Heard , Grande Terre (Kerguelen) and Bouvet . During glacial periods of the Quaternary, Taiwan , Hawaii on Mauna Kea and Tenerife also had large alpine glaciers, while
6655-686: The Treaty of Kiel formally ceded Iceland to Denmark in 1814. Influenced by ideals of nationalism after the French Revolution , Iceland's struggle for independence took form and culminated in the Danish–Icelandic Act of Union in 1918, with the establishment of the Kingdom of Iceland , sharing through a personal union the incumbent monarch of Denmark . During the occupation of Denmark in World War II, Iceland voted overwhelmingly to become
6776-456: The Vestmannaeyjar archipelago. Lakes and glaciers cover 14.3% of its surface; only 23% is vegetated. The largest lakes are Þórisvatn reservoir: 83–88 km (32–34 sq mi) and Þingvallavatn : 82 km (32 sq mi); other important lakes include Lagarfljót and Mývatn . Jökulsárlón is the deepest lake, at 248 m (814 ft). Geologically, Iceland is part of
6897-609: The 1850s under the leadership of Jón Sigurðsson , based on the burgeoning Icelandic nationalism inspired by the Fjölnismenn and other Danish-educated Icelandic intellectuals. In 1874, Denmark granted Iceland a constitution and limited home rule. This was expanded in 1904, and Hannes Hafstein served as the first Minister for Iceland in the Danish cabinet. The Danish–Icelandic Act of Union , an agreement with Denmark signed on 1 December 1918 and valid for 25 years, recognised Iceland as
7018-448: The 1990s and 2000s. In a study using data from January 1993 through October 2005, more events were detected every year since 2002, and twice as many events were recorded in 2005 as there were in any other year. Ogives or Forbes bands are alternating wave crests and valleys that appear as dark and light bands of ice on glacier surfaces. They are linked to seasonal motion of glaciers; the width of one dark and one light band generally equals
7139-607: The Arctic Circle contains the northernmost habitation of Iceland, whereas Kolbeinsey contains the northernmost point of Iceland. Iceland has three national parks : Vatnajökull National Park , Snæfellsjökull National Park , and Þingvellir National Park . The country is considered a "strong performer" in environmental protection, having been ranked 13th in Yale University 's Environmental Performance Index of 2012. A geologically young land at 16 to 18 million years old, Iceland
7260-625: The Commonwealth of Nations, such as Canada, whose sovereign is King Charles III . During World War II, Iceland joined Denmark in asserting neutrality. After the German occupation of Denmark on 9 April 1940, the Althing replaced the King with a regent and declared that the Icelandic government would take control of its own defence and foreign affairs. A month later, British armed forces conducted Operation Fork ,
7381-620: The Left-Green Movement, headed by Prime Minister Katrín Jakobsdóttir. In April 2024, Bjarni Benediktsson of the Independence party succeeded Katrín Jakobsdóttir as prime minister. Iceland is at the juncture of the North Atlantic and Arctic Oceans. The main island is entirely south of the Arctic Circle , which passes through the small Icelandic island of Grímsey off the main island's northern coast. The country lies between latitudes 63 and 68°N , and longitudes 25 and 13°W . Iceland
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#17330855661127502-680: The US Marshall Plan programme, through which Icelanders received the most aid per capita of any European country (at US$ 209, with the war-ravaged Netherlands a distant second at US$ 109). Vigdís Finnbogadóttir assumed Iceland's presidency on 1 August 1980, making her the first elected female head of state in the world. The 1970s were marked by the Cod Wars —several disputes with the United Kingdom over Iceland's extension of its fishing limits to 200 nmi (370 km) offshore. Iceland hosted
7623-412: The advance of many alpine glaciers between 1950 and 1985, but since 1985 glacier retreat and mass loss has become larger and increasingly ubiquitous. Glaciers move downhill by the force of gravity and the internal deformation of ice. At the molecular level, ice consists of stacked layers of molecules with relatively weak bonds between layers. When the amount of strain (deformation) is proportional to
7744-520: The air from the snow turns it into "glacial ice". This glacial ice will fill the cirque until it "overflows" through a geological weakness or vacancy, such as a gap between two mountains. When the mass of snow and ice reaches sufficient thickness, it begins to move by a combination of surface slope, gravity, and pressure. On steeper slopes, this can occur with as little as 15 m (49 ft) of snow-ice. In temperate glaciers, snow repeatedly freezes and thaws, changing into granular ice called firn . Under
7865-430: The amount of melting at surface of the glacier, the faster the ice will flow. Basal sliding is dominant in temperate or warm-based glaciers. The presence of basal meltwater depends on both bed temperature and other factors. For instance, the melting point of water decreases under pressure, meaning that water melts at a lower temperature under thicker glaciers. This acts as a "double whammy", because thicker glaciers have
7986-713: The annual movement of the glacier. Ogives are formed when ice from an icefall is severely broken up, increasing ablation surface area during summer. This creates a swale and space for snow accumulation in the winter, which in turn creates a ridge. Sometimes ogives consist only of undulations or color bands and are described as wave ogives or band ogives. Glaciers are present on every continent and in approximately fifty countries, excluding those (Australia, South Africa) that have glaciers only on distant subantarctic island territories. Extensive glaciers are found in Antarctica, Argentina, Chile, Canada, Pakistan, Alaska, Greenland and Iceland. Mountain glaciers are widespread, especially in
8107-432: The bedrock has frequent fractures on the surface, glacial erosion rates tend to increase as plucking is the main erosive force on the surface; when the bedrock has wide gaps between sporadic fractures, however, abrasion tends to be the dominant erosive form and glacial erosion rates become slow. Glaciers in lower latitudes tend to be much more erosive than glaciers in higher latitudes, because they have more meltwater reaching
8228-445: The bedrock. By mapping the direction of the striations, researchers can determine the direction of the glacier's movement. Similar to striations are chatter marks , lines of crescent-shape depressions in the rock underlying a glacier. They are formed by abrasion when boulders in the glacier are repeatedly caught and released as they are dragged along the bedrock. The rate of glacier erosion varies. Six factors control erosion rate: When
8349-457: The country is Icelandic . Iceland is on a rift between tectonic plates , and its geologic activity includes geysers and frequent volcanic eruptions . The interior consists of a volcanic plateau with sand and lava fields , mountains and glaciers , and many glacial rivers flow to the sea through the lowlands . Iceland is warmed by the Gulf Stream and has a temperate climate , despite
8470-566: The country's climate continued to grow colder, resulting in mass emigration to the New World , particularly to the region of Gimli , Manitoba in Canada, which was sometimes referred to as New Iceland . About 15,000 people emigrated, out of a total population of 70,000. A national consciousness arose in the first half of the 19th century, inspired by romantic and nationalist ideas from mainland Europe. An Icelandic independence movement took shape in
8591-416: The country's total exports. Birds, especially seabirds, are an important part of Iceland's animal life. Atlantic puffins , skuas , and black-legged kittiwakes nest on its sea cliffs. Commercial whaling is practised intermittently along with scientific whale hunts. Whale watching has become an important part of Iceland's economy since 1997. Around 1,300 species of insects are known in Iceland. This
8712-417: The country. Due to the reforestation efforts, the forest cover of Iceland increased six-fold since the 1990s. This helps to offset carbon emissions, prevent sand storms and increase the productivity of farms. The planting of new forests has increased the number of trees, but the result does not compare to the original forests. Some of the planted forests include introduced species . The tallest tree in Iceland
8833-559: The created ice's density. The word glacier is a loanword from French and goes back, via Franco-Provençal , to the Vulgar Latin glaciārium , derived from the Late Latin glacia , and ultimately Latin glaciēs , meaning "ice". The processes and features caused by or related to glaciers are referred to as glacial. The process of glacier establishment, growth and flow is called glaciation . The corresponding area of study
8954-467: The deep profile of fjords , which can reach a kilometer in depth as ice is topographically steered into them. The extension of fjords inland increases the rate of ice sheet thinning since they are the principal conduits for draining ice sheets. It also makes the ice sheets more sensitive to changes in climate and the ocean. Although evidence in favor of glacial flow was known by the early 19th century, other theories of glacial motion were advanced, such as
9075-483: The deformation to become a plastic flow rather than elastic. Then, the glacier will begin to deform under its own weight and flow across the landscape. According to the Glen–Nye flow law , the relationship between stress and strain, and thus the rate of internal flow, can be modeled as follows: where: The lowest velocities are near the base of the glacier and along valley sides where friction acts against flow, causing
9196-513: The eruption, known as the Mist Hardships ( Icelandic : Móðuharðindin ), over half of all livestock in the country died. Around a quarter of the population starved to death in the ensuing famine . In 1814, following the Napoleonic Wars , Denmark-Norway was broken up into two separate kingdoms via the Treaty of Kiel , but Iceland remained a Danish dependency. Throughout the 19th century,
9317-418: The essentially correct explanation in the 1840s, although it was several decades before it was fully accepted. The top 50 m (160 ft) of a glacier are rigid because they are under low pressure . This upper section is known as the fracture zone and moves mostly as a single unit over the plastic-flowing lower section. When a glacier moves through irregular terrain, cracks called crevasses develop in
9438-570: The events known locally as the Turkish Abductions , in which hundreds of residents were taken into slavery in North Africa and dozens killed; this was the only invasion in Icelandic history to have casualties. The 1707–08 Iceland smallpox epidemic is estimated to have killed a quarter to a third of the population. In 1783 the Laki volcano erupted, with devastating effects. In the years following
9559-464: The first permanent residents of Iceland to be documented. The Norwegian-Norse chieftain Ingólfr Arnarson built his homestead in present-day Reykjavík in 874. Ingólfr was followed by many other emigrant settlers, largely Scandinavians and their thralls , many of whom were Irish or Scottish . By 930, most arable land on the island had been claimed; the Althing , a legislative and judicial assembly
9680-475: The fracture zone. Crevasses form because of differences in glacier velocity. If two rigid sections of a glacier move at different speeds or directions, shear forces cause them to break apart, opening a crevasse. Crevasses are seldom more than 46 m (150 ft) deep but, in some cases, can be at least 300 m (1,000 ft) deep. Beneath this point, the plasticity of the ice prevents the formation of cracks. Intersecting crevasses can create isolated peaks in
9801-453: The glacier to melt, creating a water source that is especially important for plants, animals and human uses when other sources may be scant. However, within high-altitude and Antarctic environments, the seasonal temperature difference is often not sufficient to release meltwater. Since glacial mass is affected by long-term climatic changes, e.g., precipitation , mean temperature , and cloud cover , glacial mass changes are considered among
9922-428: The glacier will be accommodated by motion in the sediments, or if it'll be able to slide. A soft bed, with high porosity and low pore fluid pressure, allows the glacier to move by sediment sliding: the base of the glacier may even remain frozen to the bed, where the underlying sediment slips underneath it like a tube of toothpaste. A hard bed cannot deform in this way; therefore the only way for hard-based glaciers to move
10043-504: The glacier's surface area, more if the glacier calves icebergs. Ice in the accumulation zone is deep enough to exert a downward force that erodes underlying rock. After a glacier melts, it often leaves behind a bowl- or amphitheater-shaped depression that ranges in size from large basins like the Great Lakes to smaller mountain depressions known as cirques . The accumulation zone can be subdivided based on its melt conditions. The health of
10164-600: The government enterprise Flugstodir ltd. in 2006, the operational services were separated from the regulatory authority of the Icelandic Civil Aviation Administration . 31 January 2010 Flugstodir and Keflavik International Airport Ltd. were merged into a private limited company with 100 per cent state ownership, Isavia ltd. Isavia ohf. owns three subsidiaries, each specializing in distinct aspects of aviation and airport services. These subsidiaries are wholly owned and operate with unique corporate strategies that align with our broader support strategies. Each subsidiary's executive team
10285-463: The greatest migration from Iceland since 1887, with a net emigration of 5,000 people in 2009. Iceland's economy stabilised under the government of Jóhanna Sigurðardóttir and grew by 1.6% in 2012. The centre-right Independence Party was returned to power in coalition with the Progressive Party in the 2013 election. In the following years, Iceland saw a surge in tourism as the country became
10406-614: The ice at the bottom of the glacier move more slowly than ice at the top. In alpine glaciers, friction is also generated at the valley's sidewalls, which slows the edges relative to the center. Mean glacial speed varies greatly but is typically around 1 m (3 ft) per day. There may be no motion in stagnant areas; for example, in parts of Alaska, trees can establish themselves on surface sediment deposits. In other cases, glaciers can move as fast as 20–30 m (70–100 ft) per day, such as in Greenland's Jakobshavn Isbræ . Glacial speed
10527-420: The ice sheets of Antarctica and Greenland, has been estimated at 170,000 km . Glacial ice is the largest reservoir of fresh water on Earth, holding with ice sheets about 69 percent of the world's freshwater. Many glaciers from temperate , alpine and seasonal polar climates store water as ice during the colder seasons and release it later in the form of meltwater as warmer summer temperatures cause
10648-544: The ice to act as a lever that loosens the rock by lifting it. Thus, sediments of all sizes become part of the glacier's load. If a retreating glacier gains enough debris, it may become a rock glacier , like the Timpanogos Glacier in Utah. Abrasion occurs when the ice and its load of rock fragments slide over bedrock and function as sandpaper, smoothing and polishing the bedrock below. The pulverized rock this process produces
10769-488: The ice, called seracs . Crevasses can form in several different ways. Transverse crevasses are transverse to flow and form where steeper slopes cause a glacier to accelerate. Longitudinal crevasses form semi-parallel to flow where a glacier expands laterally. Marginal crevasses form near the edge of the glacier, caused by the reduction in speed caused by friction of the valley walls. Marginal crevasses are largely transverse to flow. Moving glacier ice can sometimes separate from
10890-411: The idea that meltwater, refreezing inside glaciers, caused the glacier to dilate and extend its length. As it became clear that glaciers behaved to some degree as if the ice were a viscous fluid, it was argued that "regelation", or the melting and refreezing of ice at a temperature lowered by the pressure on the ice inside the glacier, was what allowed the ice to deform and flow. James Forbes came up with
11011-418: The increased pressure can facilitate melting. Most importantly, τ D is increased. These factors will combine to accelerate the glacier. As friction increases with the square of velocity, faster motion will greatly increase frictional heating, with ensuing melting – which causes a positive feedback, increasing ice speed to a faster flow rate still: west Antarctic glaciers are known to reach velocities of up to
11132-423: The infrared OH stretching mode of the water molecule. (Liquid water appears blue for the same reason. The blue of glacier ice is sometimes misattributed to Rayleigh scattering of bubbles in the ice.) A glacier originates at a location called its glacier head and terminates at its glacier foot, snout, or terminus . Glaciers are broken into zones based on surface snowpack and melt conditions. The ablation zone
11253-476: The invasion and occupation of the country, violating Icelandic neutrality . In 1941, the Government of Iceland, friendly to Britain, invited the then-neutral United States to take over its defence so that Britain could use its troops elsewhere. On 31 December 1943, the Danish–Icelandic Act of Union expired after 25 years. Beginning on 20 May 1944, Icelanders voted in a four-day plebiscite on whether to terminate
11374-523: The island was first settled, it was extensively forested, with around 30% of the land covered in trees. In the late 12th century, Ari the Wise described it in the Íslendingabók as "forested from mountain to sea shore". Permanent human settlement greatly disturbed the isolated ecosystem of thin, volcanic soils and limited species diversity . The forests were heavily exploited over the centuries for firewood and timber. Deforestation , climatic deterioration during
11495-440: The island was then called Garðarshólmur, which means "Garðar's Isle". Then came a Viking named Flóki Vilgerðarson ; his daughter drowned en route, then his livestock starved to death. The sagas say that the rather despondent Flóki climbed a mountain and saw a fjord ( Arnarfjörður ) full of icebergs, which led him to give the island its new and present name. The notion that Iceland's Viking settlers chose that name to discourage
11616-604: The island with the winds, but they are not able to breed there. No native or free-living reptiles or amphibians are on the island. The animals of Iceland include the Icelandic sheep , cattle , chickens , goats , the sturdy Icelandic horse , and the Icelandic Sheepdog , all descendants of animals imported by Europeans. Wild mammals include the Arctic fox, mink , mice, rats, rabbits, and reindeer . Polar bears occasionally visit
11737-415: The island, travelling from Greenland on icebergs, but no Icelandic populations exist. In June 2008, two polar bears arrived in the same month. Marine mammals include the grey seal ( Halichoerus grypus ) and harbour seal ( Phoca vitulina ). Many species of fish live in the ocean waters surrounding Iceland, and the fishing industry is a major part of Iceland's economy, accounting for roughly half of
11858-437: The last Catholic bishop of Hólar , was beheaded in 1550 along with two of his sons. The country subsequently became officially Lutheran, and Lutheranism has since remained the dominant religion. In the 17th and 18th centuries, Denmark imposed harsh trade restrictions on Iceland. Natural disasters, including volcanic eruptions and disease, contributed to a decreasing population. In the summer of 1627, Barbary Pirates committed
11979-679: The most deformation. Velocity increases inward toward the center line and upward, as the amount of deformation decreases. The highest flow velocities are found at the surface, representing the sum of the velocities of all the layers below. Because ice can flow faster where it is thicker, the rate of glacier-induced erosion is directly proportional to the thickness of overlying ice. Consequently, pre-glacial low hollows will be deepened and pre-existing topography will be amplified by glacial action, while nunataks , which protrude above ice sheets, barely erode at all – erosion has been estimated as 5 m per 1.2 million years. This explains, for example,
12100-445: The most sensitive indicators of climate change and are a major source of variations in sea level . A large piece of compressed ice, or a glacier, appears blue , as large quantities of water appear blue , because water molecules absorb other colors more efficiently than blue. The other reason for the blue color of glaciers is the lack of air bubbles. Air bubbles, which give a white color to ice, are squeezed out by pressure increasing
12221-472: The northeastern hinterland. The temperature records for Reykjavík are 26.2 °C (79.2 °F) on 30 July 2008, and −24.5 °C (−12.1 °F) on 21 January 1918. The entire country is in a single ecoregion , the Iceland boreal birch forests and alpine tundra . Some areas are covered by glaciers . Phytogeographically , Iceland belongs to the Arctic province of the Circumboreal Region within
12342-410: The northern tip of Labrador . Iceland is the world's 18th-largest island , and Europe's second-largest island after Great Britain and before Ireland. The main island covers 101,826 km (39,315 sq mi), but the entire country is 103,000 km (40,000 sq mi) in size, of which 62.7% is tundra . Iceland contains about 30 minor islands, including the lightly populated Grímsey and
12463-401: The ocean in a series of volcanic eruptions between 8 November 1963 and 5 June 1968. Only scientists researching the growth of new life are allowed to visit the island. The country has around 30 active volcanic systems. Within each are volcano-tectonic fissure systems and many, but not all of them, also have at least one central volcano (mostly in the form of a stratovolcano , sometimes of
12584-507: The personal union with Denmark, abolish the monarchy, and establish a republic. The vote was 97% to end the union, and 95% in favour of the new republican constitution. Iceland formally became a republic on 17 June 1944, with Sveinn Björnsson as its first president. In 1946, the US Defence Force Allied left Iceland. The nation formally became a member of NATO on 30 March 1949, amid domestic controversy and riots . On 5 May 1951,
12705-721: The pooling of meltwater at the base of the glacier — perhaps delivered from a supraglacial lake — or the simple accumulation of mass beyond a critical "tipping point". Temporary rates up to 90 m (300 ft) per day have occurred when increased temperature or overlying pressure caused bottom ice to melt and water to accumulate beneath a glacier. In glaciated areas where the glacier moves faster than one km per year, glacial earthquakes occur. These are large scale earthquakes that have seismic magnitudes as high as 6.1. The number of glacial earthquakes in Greenland peaks every year in July, August, and September and increased rapidly in
12826-410: The pressure of the layers of ice and snow above it, this granular ice fuses into denser firn. Over a period of years, layers of firn undergo further compaction and become glacial ice. Glacier ice is slightly more dense than ice formed from frozen water because glacier ice contains fewer trapped air bubbles. Glacial ice has a distinctive blue tint because it absorbs some red light due to an overtone of
12947-509: The sea, often with an ice tongue , like Mertz Glacier . Tidewater glaciers are glaciers that terminate in the sea, including most glaciers flowing from Greenland, Antarctica, Baffin , Devon , and Ellesmere Islands in Canada, Southeast Alaska , and the Northern and Southern Patagonian Ice Fields . As the ice reaches the sea, pieces break off or calve, forming icebergs . Most tidewater glaciers calve above sea level, which often results in
13068-576: The service level, operations, and maintenance of these state-owned airports as part of the public transportation system. Fríhöfnin operates three duty-free stores at KEF under an operating license agreement with Isavia. Two of these stores serve departing passengers, and one serves arriving passengers. Isavia operates all public airports in Iceland. A total of 2,165,423 international passengers and 781,357 domestic passengers passed through these airports in 2011. Iceland Iceland ( Icelandic : Ísland , pronounced [ˈistlant] )
13189-621: The settlement of their verdant isle is most likely a myth. According to both Landnámabók and Íslendingabók , monks known as the Papar lived in Iceland before Scandinavian settlers arrived, possibly members of a Hiberno-Scottish mission . An archaeological excavation has revealed the ruins of a cabin in Hafnir on the Reykjanes peninsula . Carbon dating indicates that it was abandoned sometime between 770 and 880. In 2016, archaeologists uncovered
13310-651: The signing of the Old Covenant in 1262, which ended the Commonwealth and brought Iceland under the Norwegian crown. Possession of Iceland passed from the Kingdom of Norway (872–1397) to the Kalmar Union in 1415, when the kingdoms of Norway, Denmark, and Sweden were united. After the break-up of the union in 1523, it remained a Norwegian dependency, as a part of Denmark–Norway . Infertile soil, volcanic eruptions, deforestation, and an unforgiving climate made for harsh life in
13431-470: The smallest population of any NATO member and is the only one with no standing army , possessing only a lightly armed coast guard . The Sagas of Icelanders say that a Norwegian named Naddodd (or Naddador) was the first Norseman to reach Iceland; in the ninth century, he named it Snæland or "Snowland" because it was snowing. Following Naddodd, the Swede Garðar Svavarsson arrived, and so
13552-463: The south coast is warmer, wetter, and windier than the north. The Central Highlands are the coldest part of the country. Low-lying inland areas in the north are the aridest. Snowfall in winter is more common in the north than in the south. The highest air temperature recorded was 30.5 °C (86.9 °F) on 22 June 1939 at Teigarhorn on the southeastern coast. The lowest was −38 °C (−36.4 °F) on 22 January 1918 at Grímsstaðir and Möðrudalur in
13673-409: The stagnant ice above, forming a bergschrund . Bergschrunds resemble crevasses but are singular features at a glacier's margins. Crevasses make travel over glaciers hazardous, especially when they are hidden by fragile snow bridges . Below the equilibrium line, glacial meltwater is concentrated in stream channels. Meltwater can pool in proglacial lakes on top of a glacier or descend into the depths of
13794-423: The stress being applied, ice will act as an elastic solid. Ice needs to be at least 30 m (98 ft) thick to even start flowing, but once its thickness exceeds about 50 m (160 ft) (160 ft), stress on the layer above will exceeds the inter-layer binding strength, and then it'll move faster than the layer below. This means that small amounts of stress can result in a large amount of strain, causing
13915-438: The surface snowpack may experience seasonal melting. A subpolar glacier includes both temperate and polar ice, depending on the depth beneath the surface and position along the length of the glacier. In a similar way, the thermal regime of a glacier is often described by its basal temperature. A cold-based glacier is below freezing at the ice-ground interface and is thus frozen to the underlying substrate. A warm-based glacier
14036-417: The weight of the ice is supported by the underlying water, and the glacier is afloat. Glaciers may also move by basal sliding , where the base of the glacier is lubricated by the presence of liquid water, reducing basal shear stress and allowing the glacier to slide over the terrain on which it sits. Meltwater may be produced by pressure-induced melting, friction or geothermal heat . The more variable
14157-534: The world with similar climates include the Aleutian Islands , the Alaska Peninsula , and Tierra del Fuego , although these regions are closer to the equator. Despite its proximity to the Arctic, the island's coasts remain ice-free through the winter. Ice incursions are rare, with the last having occurred on the north coast in 1969. The climate varies between different parts of the island. Generally speaking,
14278-680: The world's wealthiest and most developed nations. In 1994 it became a part of the European Economic Area , further diversifying its economy into sectors such as finance, biotechnology, and manufacturing . Iceland has a market economy with relatively low taxes , compared to other OECD countries, as well as the highest trade union membership in the world . It maintains a Nordic social welfare system that provides universal health care and tertiary education . Iceland ranks highly in international comparisons of national performance, such as quality of life, education, protection of civil liberties, government transparency, and economic freedom. It has
14399-507: Was adopted by consensus around 999–1000, although Norse paganism persisted among segments of the population for some years afterward. The Icelandic Commonwealth lasted until the 13th century when the political system devised by the original settlers proved unable to cope with the increasing power of Icelandic chieftains. The internal struggles and civil strife of the Age of the Sturlungs led to
14520-493: Was governed as an independent commonwealth under the native parliament, the Althing , one of the world's oldest functioning legislative assemblies. After a period of civil strife , Iceland acceded to Norwegian rule in the 13th century. In 1397, Iceland followed Norway's integration into the Kalmar Union along with the kingdoms of Denmark and Sweden, coming under de facto Danish rule upon its dissolution in 1523. The Danish kingdom introduced Lutheranism by force in 1550, and
14641-539: Was initiated to regulate the Icelandic Commonwealth . The lack of arable land also served as an impetus to the settlement of Greenland starting in 986. The period of these early settlements coincided with the Medieval Warm Period , when temperatures were similar to those of the early 20th century. At this time about 25% of Iceland was covered with forest, compared to 1% in the present day. Christianity
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