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24-637: The strait separates Kulusuk Island in the southwest from Apusiaajik Island in the northeast. The strait waterway connects the Torsuut Tunoq sound in the northwest with the North Atlantic in the southeast. Icelandair STOL aircraft approach Kulusuk Airport on the way from Nerlerit Inaat and Reykjavík flying directly over the southern end of Apusiaajik Island and then over the Ikaasaartik Strait, in an air canyon between

48-657: A pyramidal peak is created. In some cases, this peak will be made accessible by one or more arêtes. The Matterhorn in the European Alps is an example of such a peak. Where cirques form one behind the other, a cirque stairway results, as at the Zastler Loch in the Black Forest . As glaciers can only originate above the snowline, studying the location of present-day cirques provides information on past glaciation patterns and on climate change. Although

72-577: A larger leeward deposition zone, furthering the process of glaciation. Debris (or till) in the ice also may abrade the bed surface; should ice move down a slope it would have a 'sandpaper effect' on the bedrock beneath, on which it scrapes. Eventually, the hollow may become a large bowl shape in the side of the mountain, with the headwall being weathered by ice segregation, and as well as being eroded by plucking . The basin will become deeper as it continues to be eroded by ice segregation and abrasion. Should ice segregation, plucking and abrasion continue,

96-491: A less common usage, the term cirque is also used for amphitheatre-shaped, fluvial-erosion features. For example, an approximately 200 square kilometres (77 sq mi) anticlinal erosion cirque is at 30°35′N 34°45′E  /  30.583°N 34.750°E  / 30.583; 34.750  ( Negev anticlinal erosion cirque ) on the southern boundary of the Negev highlands . This erosional cirque or makhtesh

120-412: A mountainside near the firn line , they are typically partially surrounded on three sides by steep cliffs . The highest cliff is often called a headwall . The fourth side forms the lip , threshold or sill , the side at which the glacier flowed away from the cirque. Many glacial cirques contain tarns dammed by either till (debris) or a bedrock threshold. When enough snow accumulates, it can flow out

144-587: Is an island in the Sermersooq municipality on the southeastern shore of Greenland . It is an outlying island in the Ammassalik archipelago of islands on the coast of the North Atlantic . The island is home to Kulusuk , the fourth-largest settlement on the entire eastern coast of Greenland. The island has an area of 41.98 km , and measures 8 km (5.0 mi) from north to south and 11 km (6.8 mi) from west to east. The Kulusuk Airport on

168-440: Is formed by intermittent river flow cutting through layers of limestone and chalk leaving sheer cliffs. A common feature for all fluvial -erosion cirques is a terrain which includes erosion resistant upper structures overlying materials which are more easily eroded. Glacial cirques are found amongst mountain ranges throughout the world; 'classic' cirques are typically about one kilometer long and one kilometer wide. Situated high on

192-479: Is most often overdeepened below the level of the cirque's low-side outlet (stage) and its down-slope (backstage) valley. If the cirque is subject to seasonal melting, the floor of the cirque most often forms a tarn (small lake) behind a dam, which marks the downstream limit of the glacial overdeepening. The dam itself can be composed of moraine , glacial till , or a lip of the underlying bedrock . The fluvial cirque or makhtesh , found in karst landscapes,

216-400: Is one larger lake on the island, Qalorujoornep Tasia , located in a post-glacial cirque in the heart of the island directly west of the western wall of Qalorujoorneq. Its northern shore is situated just shy of the shallow saddle in the northwestern ridge of the mountain, directly above the airport. During the brief summer a stream flows to the west, to then turn north through the depression in

240-416: Is open on the downhill side, while the cupped section is generally steep. Cliff-like slopes, down which ice and glaciated debris combine and converge, form the three or more higher sides. The floor of the cirque ends up bowl-shaped, as it is the complex convergence zone of combining ice flows from multiple directions and their accompanying rock burdens. Hence, it experiences somewhat greater erosion forces and

264-733: Is the Naujaangivit cape ( Danish : Kap Dan − a name often extended to the settlement or the island) under the Isikajia mountain (336 m (1,102.4 ft)). To the northeast the island is separated from the Apusiaajik Island by the Ikaasaartik Strait . In the north, the Torsuut Tunoq sound separates it from the small, uninhabited Akinaaq island, ultimately linking it to the Ammassalik Fjord in

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288-725: The Qalorujoorneq ridge on Kulusuk Island, and the Kangaartik and Iperajivit summits on Apusiaajik Island. During winter pack ice and small icebergs pushed forth by the East Greenland Current ram against the northeastern coast, blocking the narrow strait and facilitating the freeze of the much wider Torsuut Tunoq sound. 65°34′10″N 37°03′00″W  /  65.56944°N 37.05000°W  / 65.56944; -37.05000 Kulusuk Island Kulusuk Island ( Greenlandic : Kulusup qeqertaa )

312-456: The Latin word circus ) is an amphitheatre -like valley formed by glacial erosion . Alternative names for this landform are corrie (from Scottish Gaelic : coire , meaning a pot or cauldron ) and cwm ( Welsh for 'valley'; pronounced [kʊm] ). A cirque may also be a similarly shaped landform arising from fluvial erosion. The concave shape of a glacial cirque

336-451: The bergschrund changes very little, however, studies have shown that ice segregation (frost shattering) may happen with only small changes in temperature. Water that flows into the bergschrund can be cooled to freezing temperatures by the surrounding ice, allowing freeze-thaw free mechanisms to occur. If two adjacent cirques erode toward one another, an arête , or steep sided ridge, forms. When three or more cirques erode toward one another,

360-467: The center of the island, to join the second-largest lake on the island, serving as a water reservoir for the settlement. The reservoir empties into a smaller pond on the edge of the village just south of the coastal scarp. The outflow from the reservoir leads to the west, through a series of smaller interior lakes, draining into Tiivtingaleq bay. All lakes and streams are frozen during winter. Cirque A cirque ( French: [siʁk] ; from

384-406: The dimensions of the cirque will increase, but the proportion of the landform would remain roughly the same. A bergschrund forms when the movement of the glacier separates the moving ice from the stationary ice, forming a crevasse. The method of erosion of the headwall lying between the surface of the glacier and the cirque's floor has been attributed to freeze-thaw mechanisms. The temperature within

408-503: The island is one of the two airports on the entire eastern Greenland coast. Among the archaeological ruins on Kulusuk the ancient settlement of Ikaasap Ittiva (Ikâsap Igtiva) is located near the shore at the northern end of the island. This site belongs to the oldest phase of the Saqqaq culture , around 2000 BCE. The island is hilly throughout, with several distinct mountains dominating the eastern and southern coast. The southernmost point

432-409: The northwest. To the south and east the island shores are washed by the icy waters of the North Atlantic , through which flows the East Greenland Current . The coast of most of the island is mostly undeveloped, with the mountain walls and slopes falling directly into the ocean. In the west there are several small peninsulas and bays. The largest of the latter is Tiivtingaleq bay to the southwest of

456-536: The opening of the bowl and form valley glaciers which may be several kilometers long. Cirques form in conditions which are favorable; in the Northern Hemisphere the conditions include the north-east slope, where they are protected from the majority of the Sun's energy and from the prevailing winds. These areas are sheltered from heat, encouraging the accumulation of snow; if the accumulation of snow increases,

480-457: The settlement, host to a small harbour used both in all seasons as a starting point for hunting trips. A group of tiny skerries surrounds the coastline in the west, as well as in the north in the vicinity of the village. From north to south, the western skerries are: Sitte , Puullortuluk , Ittitalik , Ittive , and Saattit . The island is hilly, and unlike its immediate neighbours, not glaciated, albeit covered with ice for more than half of

504-472: The snow turns into glacial ice. The process of nivation follows, whereby a hollow in a slope may be enlarged by ice segregation weathering and glacial erosion. Ice segregation erodes the vertical rock face and causes it to disintegrate, which may result in an avalanche bringing down more snow and rock to add to the growing glacier. Eventually, this hollow may become large enough that glacial erosion intensifies. The enlarging of this open ended concavity creates

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528-475: The tallest volcanic structure in the Indian Ocean . The island consists of an active shield-volcano ( Piton de la Fournaise ) and an extinct, deeply eroded volcano ( Piton des Neiges ). Three cirques have eroded there in a sequence of agglomerated, fragmented rock and volcanic breccia associated with pillow lavas overlain by more coherent, solid lavas. A common feature for all fluvial-erosion cirques

552-483: The year. The highest point on the island is the summit of Qalorujoorneq , at 676 m (2,217.8 ft) topping a wide mountain massif in the southeast, directly above the Kulusuk Airport . Qalorujoorneq has three ridges. Its southeastern ridge extends to the southeastern promontory on the island, with two distinct peaks: Saajat at 603 metres (1,978 ft) and Kangeq at 280 metres (919 ft). There

576-603: Was formed by intermittent river flow in the Makhtesh Ramon cutting through layers of limestone and chalk, resulting in cirque walls with a sheer 200 metres (660 ft) drop. The Cirque du Bout du Monde is another such feature, created in karst terraine in the Burgundy region of the department of Côte-d'Or in France . Yet another type of fluvial erosion-formed cirque is found on Réunion island , which includes

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