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101-589: There are 140 glaciers in the mountains covering about 141 square kilometres (54 sq mi) of the Lyngen Peninsula at present. Gamvikblåisen and Strupenbreen are the two largest in the outer part of the peninsula, while in the interior Fornesbreen and the Jiehkkevárri glacial complex are the largest. The bedrock consists of a belt of ophiolitic gabbro that is flanked on both sides by predominantly schistose metasediments. The gabbro belt underlies

202-424: 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

303-545: A liming agent . Rock dust can be applied to soil by hand application, via broadcast spreader or by fertigation . Where possible the rockdust can be worked into the ground either physically or by using water to wash in. In some soils which display poor levels of nutrients, application rates of 10 tonnes per hectare are required. In Australia , namely the Riverland , Riverina , Langhorne Creek , Barossa and McLaren Vale regions, rates are 3–5 tonnes per hectare . In

404-628: A defensive line for protection against Soviet advance through Norway – the Lyngen Line. ( Norwegian : Lyngenlinja ) and during the cold war, Norway and NATO re-armed this defensive line again. The Lyngen Peninsula has long been a reindeer grazing area. There are written sources that tell about the resettlement of the Swedish Sami in “Iddu-njarga”, on the Lyngen Peninsula in the 18th century. The Lapland Code of 1751 recognized

505-522: 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

606-601: 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

707-411: 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

808-433: A greater amount. Although clay-sized, the flour particles are not clay minerals but typically ground up quartz and feldspar . Rock flour is carried out from the system via meltwater streams, where the particles travel in suspension . Rock flour particles may travel great distances either suspended in water or carried by the wind, in the latter case forming deposits called loess . Rock flour , artificial or natural,

909-408: 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

1010-404: 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

1111-460: 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,

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1212-632: A pilot project on the use of glacial rock, granite and basaltic fines by the U.S. Department of Agriculture exists at the Henry A. Wallace Beltsville Agricultural Research Center . The SEER Centre in Scotland is a leading source of information on the use of rock dusts and mineral fines. The Soil Remineralization Forum was established with sponsorship from the Scottish Environment Protection Agency and has commissioned

1313-525: A portfolio of research into the benefits of using mineral fines. The Forum provides an interface among research, environmentalists , and industry. SEER's research claims that the benefits of adding rockdust to soil include increased moisture-holding properties in the soil, improved cation exchange capacity and better soil structure and drainage . Rockdust also provides calcium , iron , magnesium , phosphorus and potassium , plus trace elements and micronutrients . By replacing these leached minerals it

1414-399: A similar size. Because the material is very small, it becomes suspended in meltwater making the water appear cloudy, which is sometimes known as glacial milk . When the sediments enter a river, they turn the river's colour grey, light brown, iridescent blue-green, or milky white. If the river flows into a glacial lake , the lake may appear turquoise in colour as a result. When flows of

1515-488: 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

1616-410: 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

1717-755: Is 3.0 °C. In January, the lowest average monthly temperature is -4.5 °C, while in July the highest is 12.5 °C. The highest mountain regions of Lyngsalpan are species-poor, while the lower mountainous regions, valleys, and forest areas show a greater diversity of both birds and animals. In the highlands, the species diversity is limited, and in general, you can only meet rock ptarmigans , ravens, and snow buntings . At lower altitudes, there are more species including passerines , waders , anseriformes . Wild mammal species include hares , red foxes , bobcats , and least weasels . There are also wolverines , lynxes , and moose . Squirrels and martens also live in

1818-468: 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

1919-490: Is a source of plant micronutrients ( minerals trace elements ) widely used in organic farming practices. Synonyms in this case include rock dust , rock powders , rock minerals , and mineral fines . The igneous rocks basalt and granite often contain the highest mineral content, whereas limestone , considered inferior in this consideration, is often deficient in the majority of essential macro-compounds, trace elements, and micronutrients . Soil remineralization (in

2020-456: 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

2121-407: 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,

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2222-411: 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

2323-406: 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

2424-434: 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

2525-416: 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

2626-401: Is claimed that soil health is increased and that this produces healthier plants. A 2022 study found that basalt dust improved soil fertility and increased available phosphorus, potassium, calcium and magnesium levels compared to soil without the basalt dust in a period of several months. Silicon is thought to be the major element effecting the strength of cell wall development. However it

2727-647: 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

2828-458: Is locked in soils due to many years of application of traditional fertilisers . The use of micronutrient-rich fertiliser enables plants to access locked phosphorus. The elements high in available 2+ valence electrons, calcium, iron and magnesium in particular contribute to paramagnetism in soil which aid in cation exchange capacity. The calcium and magnesium in high quality have the ability to neutralise pH in soils, in effect acting as

2929-897: 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

3030-494: Is the amount of available silica that has a dramatic effect on the plant strength and subsequent health. To highlight this, plants that are grown in very sandy soils, (being high in non available silica), often require a silica based fertiliser to provide available silicon. Silicon comes in silicon multi-oxide molecules (e.g. SiO 2 , SiO 4 , SiO 6 , and SiO 8 ). Each molecule shape is thought to pack in different ways to allow different levels of availability. Often phosphorus

3131-413: 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

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3232-402: 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

3333-552: 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

3434-993: 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

3535-483: The Caledonian Orogeny . The Caledonian Orogeny, which stretches from Arctic Norway through Great Britain, Ireland, and parts of Greenland, was formed as a result of the collision of the ancient continents Laurentia and Baltica 380–430 million years ago. The mountains of this folding could originally be from eight to ten kilometers in height. The geology of northern Scandinavia is dominated by two bedrocks,

3636-478: The Cascade Range of Washington State (including Diablo Lake , Gorge Lake , and Blanca Lake ). Typically, natural rock flour is formed during glacial migration , where the glacier grinds against the sides and bottom of the rock beneath it, but also is produced by freeze-and-thaw action , where the act of water freezing and expanding in cracks helps break up rock formations . Multiple cycles create

3737-644: 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

3838-760: 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

3939-793: The Precambrian basement, and the Caledonian mountain range. The Lyngen Peninsula is dominated by a 100 km slab of gabbro, lamellar diabase dikes, and other basic igneous rocks. These rocks belonged to the crust underlying part of the Iapetus Ocean during the Finnmark Orogeny and were thrust over bedrock deformed during earlier Finnmark tectonism. During the Caledonian orogeny, the Baltic subsided under Laurentia. The island arc, with its gabbro intrusions and ophiolite sequence,

4040-562: 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

4141-535: 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

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4242-832: The 17th century were merchants, Christian missionaries, and civil servants. Norwegian farmers and fishermen also lived near the resource-rich Lyngenfjord. The historical meeting of the Saami, Norwegians, and Kvens at Nordkalotten was called "the meeting of three tribes". The mountains received official names in Northern Sámi and Kven in September 2024 from the Norwegian Mapping Authority : Ittuvárit and Yykeänvaarat . Glaciers A glacier ( US : / ˈ ɡ l eɪ ʃ ər / ; UK : / ˈ ɡ l æ s i ər , ˈ ɡ l eɪ s i ər / )

4343-448: 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

4444-462: The Earth's surface and slowly cools into a crystalline mass. The lower parts of the peninsula are composed of several types of less stable rocks, mostly metamorphosed sedimentary rocks. The mountain range is dissected in several places by transverse deep mountain passes and valleys, with Kjosen, the 14-km long fjord arm of the Ullsfjorden, being the most prominent. The Lyngen Peninsula is part of

4545-633: The Earth, and rushing rivers form mineral-rich alluvial deposits. Rock dust is added to soil to improve fertility and has been tested since 1993 at the Sustainable Ecological Earth Regeneration Centre (SEER Centre) in Straloch, near Pitlochry , in Perth and Kinross , Scotland . Further testing has been undertaken by James Cook University, Townsville, Far North Queensland . Thomas J. Goreau who wrote

4646-631: The Scandinavian region's answer to Mount Blanc . Mrs Aubrey Le Blond (Mrs Lizzie Main) also climbed in Lyngen and her climbs in arctic Norway are recorded in her book 'Mountaineering in the land of the midnight sun'. Piggtinden involved the Norwegian philosopher Peter Wessel Zapffe in mountaineering but the peak was first climbed in the summer of 1920 by Henning Tønsberg and Karl Rubenson, when Zapffe himself climbed this mountain only in 1923, while

4747-412: 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

4848-520: 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

4949-430: 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

5050-713: 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

5151-521: The area. Minks and otters are found near lakes and streams. In addition to these species, there are a large number of small rodents. The area around Lyngen is located in the heart of the Cap of the North ( Norwegian : Nordkalotten ) on the border with Sweden and Finland. For centuries, Lyngen has been a meeting place for cultures, trade, religions, and conflicts between northern states. Historically, Lyngen

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5252-432: 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

5353-445: 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

5454-651: The book Geotherapy believed that mafic/ultra-mafic rock flour had a powerful effect in restoring trace minerals to soils, which increases the health and vigour of the Microorganism, Plantae, Animalia pathway and also sequesters carbon. An early experimenter was the German miller, Julius Hensel , author of Bread from Stones , who reported successful results with steinmehl (stonemeal) in the 1890s. His ideas were not taken up due to technical limitations and, according to proponents of his method, because of opposition from

5555-403: The champions of conventional fertilisers . John D. Hamaker argued that widespread remineralization of soils with rock dust would be necessary to reverse soil depletion by current agriculture and forestry practice. While this originally was an alternative concept, increasing mainstream research has been devoted to soil amendment and other benefits of rock flour application: for instance,

5656-458: The children, looked after the barn, cooked, and did the housework. Men were mainly responsible for maintaining buildings and tools, fishing, hunting, firewood, mowing, and butchering livestock, and making tools and utensils. Many men went on seasonal fishing trips, while women took care of household chores. The Kvens who crossed the border in the 18th and 19th centuries brought their customs and language with them. The Norwegians who came to Lyngen in

5757-571: 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

5858-467: 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

5959-483: 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

6060-521: The east and west Lenensbreen glaciers, with areas of 1.4 km and 0.7 km respectively. The Lenangsbreene glaciers reached the modern-day shoreline located around 4 km below the Blåvatnet around 20,000 years before present. The modern-day area of Lenangsbreene glaciers is 1.9 km, while during the Lateglacial period 18,000–20,000 years before present was 9.1 km, and the sea-level

6161-418: 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

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6262-404: The evidence of glaciation that we can observe today is only from the last ice age because, due to its length and intensity, it largely wiped out the results of previous ice ages. During the maximum ice thickness around 20,000 years ago, the Lyngen peninsula was probably covered by glaciers up to 1000–1200 m thick. During the period 9,000–13,000 years ago, the fjord and valley glaciers melted. Most of

6363-447: The first winter ascent was made in 1971. Most of the Lyngen peninsula is a pronounced mountainous area with high mountains and alpine landscapes in a wide strip along the axis of the peninsula and with lower landscape areas along the fjords on both sides of the peninsula. The Alpine central part of Lyngen is made up of gabbro and other hard rocks that resist erosion and weathering well. Gabbro forms when molten magma becomes trapped beneath

6464-762: The flour are extensive, a distinct layer of a different colour flows into the lake and begins to dissipate and settle as the flow extends from the increase in water flow from the glacier during snow melts and heavy rain periods. Examples of this phenomenon may be seen at Lake Pukaki and Lake Tekapo in New Zealand, Lake Louise , Moraine Lake , Emerald Lake , and Peyto Lake in Canada, Gjende lake in Norway, and several lakes (among others, Nordenskjöld and Pehoé ) in Chile's Torres del Paine National Park , and many lakes in

6565-475: 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

6666-491: The glacial base and facilitate sediment production and transport under the same moving speed and amount of ice. Material that becomes incorporated in a glacier is typically carried as far as the zone of ablation before being deposited. Glacial deposits are of two distinct types: Rock flour Rock flour , or glacial flour , consists of fine-grained, silt -sized particles of rock, generated by mechanical grinding of bedrock by glacial erosion or by artificial grinding to

6767-462: The glacial flour. The mountains are of alpine character, popular among extreme skiers. The highest summit is the 1,833-metre (6,014 ft) tall Jiehkkevárri , the highest mountain in Troms county; Store Lenangstind is also a prominent mountain. The British climber William Cecil Slingsby was the first to climb many of the peaks. Slingsby was very impressed with the peak of Jiehkkevárri, calling it

6868-453: 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

6969-428: 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

7070-510: 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

7171-619: 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

7272-420: 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

7373-556: 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

7474-488: 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

7575-411: 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

7676-418: 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

7777-423: 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

7878-417: The loose rock on the Lyngen Peninsula is moraines and glacial material transported by the melting of the ice sheet. After the ice age, various glacial activities were observed in the mountainous regions, which affected the landscape to a lesser extent. Frosty weathering occurred on the steep lower walls and mountain slopes. The rivers in the valleys carried the loose masses to the sea, the waves eroded and sorted

7979-679: 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,

8080-445: 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

8181-674: 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

8282-465: The precipitation coming from the west so that most of it falls on the west side and makes the east side drier. This also affects the condition of the snow and the length of the winter season. The lowlands can be considered coastal with an average annual rainfall of about 600 mm at Lyngseydet and 850 mm at the Ulsfjord. The mountains receive much more precipitation. The average annual temperature

8383-609: The present glaciation on the Lyngen Peninsula. The Lyngen Alps are sufficiently high as to give rain shadow in the interior lowland areas east of the mountains. The northward heat advection of air and water masses into the Norwegian Sea region produces some of the largest temperature anomalies in the world, with a mean January air temperature about 24 °C warmer in Tromsø than the latitudinal mean. The Lyngen Alps Landscape Reserve ( Norwegian : Lyngsalpan landskapsvernområde )

8484-410: 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

8585-461: The right of the Saami to use pastures across the state border, which was then formalized between Denmark/Norway and Finland/Sweden. In 1972, Norway terminated the reindeer herding agreement with Sweden. The way of life of the Sea Sami in this area was based on a combination of several types of crafts that ensured survival. Women were primarily responsible for running the household. They took care of

8686-460: The rugged mountains of Lyngsalpene. In the lowland areas between Oteren and Koppangen, amphibolites, greenstones, and greenshales predominate. In the lowlands on the eastern side of the Lyngen peninsula, mica schists, phyllites, and dolomites are mainly found. The lowlands on the western side are mainly composed of mica schists and a small amount of quartzites. Except for ice caps at the summits of Jiehkkevárri and Bálggesvárri, cirque glaciers dominate

8787-514: 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

8888-423: The sediments in the constantly sinking beach area, and clay was deposited on the seabed. The balance of the mass of glaciers and nearby areas ahead are climate archives that can tell about natural changes from the recent past and the current situation. In Lyngen there is a strong difference between the climate of the western and eastern parts of the peninsula. The highland area acts as a barrier and staunches most of

8989-455: The sense of re-incorporating minerals, different from remineralisation in biogeochemistry) creates fertile soils by returning minerals to the soil which have been lost by erosion, leaching, and or over-farming. It functions the same way that the Earth does: during an Ice Age, glaciers crush rock onto the Earth's soil mantle, and winds blow the dust in the form of loess all over the globe. Volcanoes erupt, spewing forth minerals from deep within

9090-622: The site must be suitable for reindeer herding. Haakon, Crown Prince of Norway took part in the opening of the landscape reserve on May 22, 2004. The area of the Lyngen Alps landscape reserve is 961.2 square kilometres (371.1 sq mi). The nature reserve extends over four municipalities in Troms county. There is a public transport connection between Tromsø and Lyngen via express boat to Nord-Lenangen and several bus routes. There are also ferries connecting Svensby and Breivikeidet, as well as

9191-409: 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

9292-423: 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

9393-438: 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

9494-615: The villages of Olderdalen and Lyngseidet . One of the main tourist attractions of Lyngen Alps is the glacier-fed lake Blåvatnet with a distinct turquoise color, located in Strupskardet valley. The proglacial lake Blåvatnet is located in the northern part of the Lyngen Peninsula in Strupskardet valley. The lake lies next to Nordre Jægervasstinden and Lenangstinden mountains and below the Eastern and Western Lenangsbreene glaciers. Strupskardelva river flows in Strupskardet valley towards

9595-430: The water opaque and bright. The glacial flour composition includes clay which is approximately 2-4 microns in diameter and silt which is around 4-65 microns in diameter. The composition of glacial flour absorbs most of the blue light and reflects some blue and green. With the elimination of the colors absorbed by both the glacial flour and the water itself, what is left is mostly green and some blue light reflected back off

9696-417: 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

9797-618: The west via a chain of six glacial lakes including Blåvatnet, providing additional meltwater source to the lake. The lake Blåvatnet is surrounded to the North by two marginal latero-frontal push moraines , formed by advancing glaciers during the Younger Dryas 12,800–11,500 years before present and to the East by three moraines formed during the early Holocene 8,900–10,400 years before present. They consist of large angular boulders with diameters of 1–5 m. These moraines were formed by ice from

9898-814: Was 87 m higher than nowadays. During 3,800–8,800 years before present the Lenangsbreene glaciers were completely melted away. Blåvatnet is capturing upstream sediments for the glacier-meltwater streams. Glaciofluvial outwash is forming a prograding delta at the head of the lake and provides suspended sediment which refracts light as an intense turquoise color , giving Blåvatnet (the Blue Lake) its name. Clear water in non-glacial lakes absorbs longer wavelengths of visible light and strongly reflects shorter blue and blue-green wavelengths, therefore, it appears blue due to Rayleigh scattering . The glacial flour in glacial waters provides stronger light reflection and makes

9999-649: Was also a border area between the Russian and the Danish-Norwegian joint taxation area. After the conclusion of peace in 1326 , Lyngen was placed as the western border of the taxable lands of the Novgorod Republic . Russia could collect taxes along the Norwegian coast as far as Lyngen. Lyngen was also a frontier region of great importance in recent history. During World War II , the Germans created

10100-453: Was established by the King of Norway on 20 February 2004 to protect one of Norway's characteristic mountain areas, which includes glaciers, moraines, valleys, and geological deposits, with biodiversity, cultural monuments, and cultural influences that characterize the landscape. The protection of natural resources within the landscape reserve is also important for the Saami culture and economy, and

10201-455: Was sandwiched between the plates and then raised to the surface of the Baltica plate. The gabbro was raised above sea level and subjected to severe erosion. The Precambrian basement dominates the large islands west of Tromsø including Senja , Kvaløya , Ringvassøya , and Vanna, while the Tromsø and Lyngen igneous sheets dominate the area east of Tromsø. Despite the long history of glaciation,

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