Difference between revisions of "Arctic Environments"

From Arctic Bioscan Wiki
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===Marine Waters===
 
===Marine Waters===
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[[File:marine_waters.png|right|200px]]
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Canada's North is a marineland. It is Canada's largest marine coastline, stretching from the western reaches of the Beaufort Sea to the eastern shores of Ungava Bay. It is home to the world's largest inland sea – Hudson Bay. It is the deep basins of the Arctic Ocean and the shallow seas that surround our northern archipelago of islands. It is filled with mammoth icebergs and tiny floes, bergy bits and ice slush. Not only is the Arctic a waterscape of spectacular beauty, it is a driver of global climate. It's a setting worth exploring.
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To learn more about Canada's Arctic marine waters, browse the topics below.
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====Cool Facts====
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'''Icebergs''' – great crystal castles shimmering in the sun, great floating boulders large enough to sink any ship – are surely the most spectacular feature of Arctic marine waters. However, their abundance varies greatly through time and space.
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If you're hoping to so some iceberg watching in the Arctic, you should go to Davis Strait. This channel is known as iceberg alley for good reason – there are usually hundreds of icebergs in it. These bergs all share the same origin: they are fragments of ancient ice broken from the snouts of glaciers, a process termed calving. It seems that most arctic glaciers like to give birth at the same time, but there is much year-to-year variation in the abundance of icebergs. Some years the glaciers launch a tiny fleet, the next year a large flotilla. If you look deeper in time, there is evidence of periods when vast armadas of icebergs were launched.
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* [[Cool Facts/Frigid Flotillas|Frigid Flotillas]]
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* [[Cool Facts/Frost Flowers|Frost Flowers]]
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* [[Cool Facts/Ice Blink / Water Sky| Ice Blink / Water Sky]]
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* [[Cool Facts/Northwest Passage|Northwest Passage]]
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* [[Cool Facts/Open Water at the North Pole|Open Water at the North Pole]]
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* [[Cool Facts/Underwater Mountain Ranges|Underwater Mountain Ranges]]
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====Ecozones====
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====Features====
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====Ice====
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====References====
  
 
===Sky===
 
===Sky===

Revision as of 00:39, 9 July 2019

Polar Environments

Polar Environments are very diverse and fascinating. This section will provide in-depth information on arctic environments and climate.

Environment

Inland Waters

Cool Facts

Inland Waters

Although precipitation levels are low enough to qualify much of the Arctic as a desert, water is abundant. There are more than one million lakes and countless rivers and streams in the Arctic. As well, many low-lying areas are wetlands covered with ponds, bogs, or marshes. This surprising abundance of surface water in a desert setting has two explanations. Firstly, the permafrost layer acts like a poor liner trapping meltwater or rain on the surface. Secondly, water on the surface is slow to evaporate because of the low air temperatures.


Inland waters of the Arctic are classified using standard terms such as ponds, lakes, rivers, or streams, but they are unusual. Arctic ponds can be more than a kilometer long and less than a meter deep. Lake basins in some areas of the Arctic were created by wind action and are all oriented in the same direction. Many long rivers flow for just a few weeks each year.

Inland Waters Ecozones

Inland Waters

The inland waters of Canada's Arctic have been divided into three ecozones whose boundaries reflect the major watersheds of northern Canada. Water bodies within the Arctic Archipelago Ecozone region originate on the Arctic Islands and discharge into the Arctic Ocean. By contrast, waters in the Hudson Bay Ecozone originate in central Canada and flow into Hudson and Ungava Bays. The third ecozone, the Yukon-Mackenzie, includes waters that flow through the western mainland and discharge into the Beaufort Sea.

Inland Waters Ice

Ice

Most Arctic lakes are covered with ice for nine or ten months of the year and some are permanently ice covered. Ice acts like a seal; there is no gas or nutrient exchange between the atmosphere and the lake. In a sense, each lake becomes its own little isolated world.

Inland Waters Lakes

There are more than one million lakes in the Canadian Arctic. Although much of the Arctic mainland is littered with them, lakes are less common on the Arctic Islands.

These lakes are far from uniform – they vary in surface area, depth, water chemistry, and even in their mode of origin. Just ten Arctic lakes are giants, with surface areas in excess of 1000 km2. Another 188 lakes have an area greater than 100 km2, but most of the others are far smaller. Arctic lakes vary in depth from just a few metres to more than 400 m. They also differ widely in chemistry – the water in some lakes is saltier than the sea, but in others it is as pure as distilled water. Browse the side menu to learn more about the six major types of lakes in the Arctic. We've also singled out ten lakes for special attention, mainly because of their large size or ecological importance.

Inland Waters Rivers

Inland Rivers

Canada's Arctic is laced with rivers large and small, deep and shallow, swift and slow moving. These rivers have served as gateways to the North – Native peoples and explorers paddled them, drank from them, admired their beauty, and occasionally lost their lives in them. Throughout the North, native settlements were first established on or near these waterways and they remain there today. All Arctic rivers and streams show seasonal variations in the extent of their flow. These shifts are smallest in the larger rivers, like the Mackenzie, which are fed by waters flowing from more southerly regions. However, rivers which are entirely situated in the Arctic show dramatic seasonal shifts in flow because they are starved of a water supply for much of the year – most of the precipitation falls as snow for about eight months. During this period, when the supply of surface water is halted, the rivers are not fed by groundwater because the permafrost layer has refrozen to the surface. However, when the snow melts, it simply runs over the permafrost, flooding the rivers with an intense pulse of meltwater. For a brief time, the rivers and streams become raging torrents, carving out large channels and transporting huge boulders.

Inland Waters Wetlands

Inland Wetlands

About 14% of Canada's surface area – nearly 1.3 million km2 – is wetlands. In fact, almost one-quarter of all the wetlands on the planet are found in Canada. As their name suggests, wetlands are areas that are waterlogged for all or much of the year. Water may just cover the surface, or it may be as deep as 2 m. As such, wetlands include marshes, bogs, ponds, and fens, but not rivers or lakes. In many wetland habitats, organic materials accumulate because of slowed decomposition, forming a layer of peat. Wetlands are found throughout the North, but they are most common in the Low Arctic and least abundant in the High Arctic. Overall, wetlands are less common in the Arctic than in the remainder of Canada, as they cover just 9% of the land area. However, the importance of northern wetlands is immense, because their productivity is higher than surrounding areas. In a very real sense, these are the oases of the Arctic.

Inland Waters References

  • Blachut SP, McCann SB. 1981. The Behaviour of a Polar Ice-Dammed Lake, Ellesmere Island, N.W.T., Canada. Arctic and Alpine Research 13: 63–74.
  • Dysen JL. 1962. The World of Ice. St. Paul: Snowy Egret Books.
  • Hobbie JE, ed. 1980. Limnology of Tundra Ponds. Stroudsburg: Dowden, Hutchinson and Ross Inc.
  • ---. 1973. Arctic Limnology: A Review. Alaskan Arctic Tundra, Technical Paper 25. n.p.
  • Mackay JR. 1969. The Mackenzie Delta. Canadian Geographic 78: 146–155.
  • National Wetlands Working Group. 1988. Wetlands of Canada. Ottawa: Sustainable Development Branch, Environment Canada. In association with Polyscience Publications Inc., Montreal. Ecological Land Classification Series No. 24.
  • Oliver DR. 1964. A Limnological Investigation of a Large Arctic Lake, Nettilling Lake, Baffin Island. Arctic 17: 69–83.
  • Rawson DS. 1954. Limnology in the North American Arctic and Subarctic. Arctic 7: 206–212.
  • Stewart DB. 1979. Our Spectacular Waterfalls in the Arctic. Canadian Geographic 98: 36–39.
  • Woo MK. 1980. Hydrology of a Small Lake in the Canadian High Arctic. Arctic and Alpine Research 12: 227–235.

Land

Land.png

Arctic landscapes are other worldly. Great glaciers coat the northern mountains with a white frosting that can be a kilometre thick. At other locations, the land lies exposed. In many places, these polar landscapes provide perfect classrooms for geology – bedrock lies on the surface or jumbles of boulders signal the retreat of glaciers. In other areas, the ground is covered with finer particles, reflecting the presence of rocks that were ground to powder by glaciers or were sediments uplifted from the sea. Viewed from the air, these surfaces show patterns of cracks and mounds that make the landscape look like the hide of some primeval beast. In a few regions, ice volcanoes erupt from the tundra.

Cool Facts

Ecozones

Arctic lands have been divided into three ecozones. To learn more about the boundaries of these ecozones and the differences between them, browse below.

Features

Land features.png

The major landscape features of the Arctic are nothing strange – they range from lowland plains to mountains higher than 3000 m. However, the sparse plant cover means that the Arctic is a place where geology has a huge impact on the eye – the colour of a scene is often due to bedrock!

The land's surface features reinforce a sense of strangeness. Great piles of rock, oddly positioned boulders, and raised beaches all reflect the past presence of glaciers. The soils, where they exist, are thin and underlain by permafrost. The surface layer has been wrinkled, pleated, and shattered by frost action to produce mosaic patterns that suggest human intervention.

Browse below to learn more about the factors responsible for the special appearance of Arctic lands. The section on topography provides background on larger scale features, while details of the landscape are described in glacial and freeze/thaw features. The final two sections provide an overview of the land itself; shifts in bedrock composition are detailed in geology, while information on soil and permafrost is provided in the last section.

Glaciers

If you were asked to describe Canada's appearance over the past two million years, the best answer would be "icy", for our lands were covered with glaciers for much of this time. Although these glaciers have now retreated to the mountains and the far north, their imprint remains, especially in the Arctic.

To learn more about the distribution of glaciers through time, the systems employed to classify them, and the factors regulating their growth, browse below.

Land Section References

  • Andrews JT. 1970. A Geomorphological Study of Post-Glacial Uplift with Particular Reference to Arctic Canada. London: Institute of British Geographers.
  • Bird JB. 1967. The Physiography of Arctic Canada. Baltimore: John Hopkins Press.
  • Brown RJE. 1970. Permafrost in Canada. Toronto: University of Toronto Press.
  • Christie RL, McMillan NJ, eds. 1994. The Geology of Melville Island, Arctic Canada. Ottawa: Canadian Government Publishing Centre. Geological Survey of Canada Bulletin No. 450.
  • Dunbar M, Greenaway KR. 1956. Arctic Canada from the Air. Ottawa: Canada Defence Research Board, Queen's Printer.
  • Dysen JL. 1962. The World of Ice. St. Paul: Snowy Egret Books.
  • Fortier YO, Blackadar RG, Glenister BF, Greiner HR, McLaren DJ, McMillan NJ, Norris AW, Roots EF, Souther JG, Thorsteinsson R, Tozier ET. 1963. Geology of the North-Central Part of the Arctic Archipelago Northwest Territories (Operation Franklin). Ottawa: Department of Mines. Geological Survey of Canada Memoir No. 320.
  • French HM. 1976. The Periglacial Environment. London: Longman.
  • French HM, Slaymaker O, eds. 1993. Canada's Cold Environments. Montreal: McGill-Queen's Press.
  • Grantz A, Johnson L, Sweeney JF, eds. 1990. The Geology of North America Volume L. The Arctic Ocean Region. Boulder: Geological Society of America.
  • Hambrey M, Jurg A. 1992. Glaciers. Cambridge: Cambridge University Press.
  • Ives JD, Barry RG, eds. 1974. Arctic and Alpine Environments. London: Methuen and Co Ltd.
  • Pewe TL, ed. 1969. The Periglacial Environment Past and Present. Montreal: McGill-Queen's University Press.
  • Pielou EC. 1994. A Naturalist's Guide to the Arctic. Chicago: University of Chicago Press.
  • Pitcher MG, ed. 1973. Arctic Geology: Proceeding of the Second International Symposium on Arctic Geology; 1971 Feb 1–4; San Francisco. Tulsa: American Association of Petroleum Geologists.
  • Raasch GO, ed. 1961. Geology of the Arctic: Proceedings of the First International Symposium on Arctic Geology. Toronto: University of Toronto Press.
  • Thoren R. 1969. Picture Atlas of the Arctic. New York: Elsevier Publishing Company.
  • Washburn AL. 1947. Reconnaissance Geology of Portions of Victoria Island and Adjacent Regions of Arctic Canada. New York: American Geological Society.

Marine Waters

Marine waters.png

Canada's North is a marineland. It is Canada's largest marine coastline, stretching from the western reaches of the Beaufort Sea to the eastern shores of Ungava Bay. It is home to the world's largest inland sea – Hudson Bay. It is the deep basins of the Arctic Ocean and the shallow seas that surround our northern archipelago of islands. It is filled with mammoth icebergs and tiny floes, bergy bits and ice slush. Not only is the Arctic a waterscape of spectacular beauty, it is a driver of global climate. It's a setting worth exploring. To learn more about Canada's Arctic marine waters, browse the topics below.

Cool Facts

Icebergs – great crystal castles shimmering in the sun, great floating boulders large enough to sink any ship – are surely the most spectacular feature of Arctic marine waters. However, their abundance varies greatly through time and space.

If you're hoping to so some iceberg watching in the Arctic, you should go to Davis Strait. This channel is known as iceberg alley for good reason – there are usually hundreds of icebergs in it. These bergs all share the same origin: they are fragments of ancient ice broken from the snouts of glaciers, a process termed calving. It seems that most arctic glaciers like to give birth at the same time, but there is much year-to-year variation in the abundance of icebergs. Some years the glaciers launch a tiny fleet, the next year a large flotilla. If you look deeper in time, there is evidence of periods when vast armadas of icebergs were launched.

Ecozones

Features

Ice

References

Sky