Great Bear Lake

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Great Bear Lake
Deline4.jpg
On the shores of Great Bear Lake
Great Bear Lake (de).png
lake map
LocationNorthwest Territories
Coordinates66°N 121°W / 66°N 121°W / 66; -121Coordinates: 66°N 121°W / 66°N 121°W / 66; -121
Primary outflowsGreat Bear River
Catchment area114,717 km2 (44,292 sq mi)[1][2]
Basin countriesCanada
Surface area31,153 km2 (12,028 sq mi)[1][2]
Average depth71.7 m (235 ft)[1][2]
Max. depth446 m (1,463 ft)[1][2]
Water volume2,236 km3 (536 cu mi)[1][2]
Residence time124 years[1]
Shore length12,719 km (1,690 mi) (plus 824 km (512 mi) island shoreline)[1][2]
Surface elevation186 m (610 ft)
FrozenNovember - July[2]
Islands26 main islands, totaling 759.3 km2 (293.2 sq mi) in area[1]
SettlementsDeline, Port Radium
References[1][2]
1 Shore length is not a well-defined measure.
 
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Great Bear Lake
Deline4.jpg
On the shores of Great Bear Lake
Great Bear Lake (de).png
lake map
LocationNorthwest Territories
Coordinates66°N 121°W / 66°N 121°W / 66; -121Coordinates: 66°N 121°W / 66°N 121°W / 66; -121
Primary outflowsGreat Bear River
Catchment area114,717 km2 (44,292 sq mi)[1][2]
Basin countriesCanada
Surface area31,153 km2 (12,028 sq mi)[1][2]
Average depth71.7 m (235 ft)[1][2]
Max. depth446 m (1,463 ft)[1][2]
Water volume2,236 km3 (536 cu mi)[1][2]
Residence time124 years[1]
Shore length12,719 km (1,690 mi) (plus 824 km (512 mi) island shoreline)[1][2]
Surface elevation186 m (610 ft)
FrozenNovember - July[2]
Islands26 main islands, totaling 759.3 km2 (293.2 sq mi) in area[1]
SettlementsDeline, Port Radium
References[1][2]
1 Shore length is not a well-defined measure.

Great Bear Lake (Slavey: Sahtú[pronunciation?], French: Grand lac de l'Ours) is the largest lake entirely in Canada (Lake Superior and Lake Huron straddling the Canada-US border are larger), the fourth largest in North America, and the eighth largest in the world. The lake is in the Northwest Territories, on the Arctic Circle between 65 and 67 degrees of northern latitude and between 118 and 123 degrees western longitude, 186 m (610 ft) above sea level. The name originated with the First Nations living on the northern shores, who called themselves Chipewyan, meaning “grizzly bear water people.” Grizzly Bear Mountain on the shore of the Lake comes from the Chipewyan, meaning, “bear large hill.”[3]

Geography[edit]

Bathymetric map of Great Bear Lake.
Smoke from Alaskan Fires in Northwestern Canada blow over Great Bear Lake.

The lake has a surface area of 31,153 km2 (12,028 sq mi) and a volume of 2,236 km3 (536 cu mi). Its maximum depth is 446 m (1,463 ft) and average depth 71.7 m (235 ft). The shoreline is 2,719 km (1,690 mi) and the catchment area of the lake is 114,717 km2 (44,292 sq mi).[4]

Prehistoric geology[edit]

Great Bear Lake lies between two major physiographic regions: the Kazan Uplands portion of the Canadian Shield and the Interior Plains. It was part of Glacial Lake McConnell in the pre-glacial valleys reshaped by erosional ice during the Pleistocene. Since, the lake has changed from post-glacial rebound following the ice melting. Precambrian rocks of the Canadian Shield form the eastern margin of the McTavish Arm. These rocks of the Precambrian are sedimentary and metamorphic deposits supplemented by igneous intrusions forming dikes and sills.

Human use[edit]

The Deline settlement is on the lake, near the headwaters of the Bear River.[5]

The mining area Port Radium, site of the Eldorado Mine where pitchblende was discovered, is located on the eastern shore.

Five fishing lodges around the lake assist commercial fishing.[2] In 1995, a 32.8 kg (72.3 lb) lake trout was caught, the largest caught by angling.[6]

In 1930, Gilbert LaBine discovered uranium deposits in the Great Bear Lake region. The Sahtu Dene people took their name from the lake.[3]

There is an ice crossing to Deline.[7][8]

Great Bear Lake. Note the smoke plumes from wildfires

Great Bear Lake is covered with ice from late November to July.[2] Between 1950 and 1974, this climatic data set was collected at Port Radium:

Climate data for Port Radium (temperature & precipitation), Norman Wells (sunshine)
MonthJanFebMarAprMayJunJulAugSepOctNovDecYear
Daily mean °C (°F)−27.0
(−16.6)
−27.0
(−16.6)
−19.1
(−2.4)
−10.7
(12.7)
1.2
(34.2)
9.0
(48.2)
12.0
(53.6)
10.6
(51.1)
5.3
(41.5)
−3.2
(26.2)
−14.8
(5.4)
−23.0
(−9.4)
−7.2
(19)
Precipitation mm (inches)11
(0.43)
8
(0.31)
14
(0.55)
6
(0.24)
14
(0.55)
14
(0.55)
35
(1.38)
43
(1.69)
25
(0.98)
27
(1.06)
25
(0.98)
14
(0.55)
236
(9.29)
Mean monthly sunshine hours26.975.6167.6230.0292.6n/an/a238.0126.153.7n/a7.3n/a
Source #1: World Lakes Database[2]
Source #2: Sunshine data from 1961-1990 Environment Canada [9]
Mackenzie River drainage basin showing Great Bear Lake's position in the Western Canadian Arctic

References[edit]

  1. ^ a b c d e f g h i Johnson, L. (1975), "Physical and chemical characteristics of Great Bear Lake", J. Fish. Res. Board Can. 32 (11): 1971–1987, doi:10.1139/f75-234  quoted at Great Bear Lake (World Lakes Database)
  2. ^ a b c d e f g h i j k Hebert, Paul (2007), "Great Bear Lake, Northwest Territories", Encyclopedia of Earth, Washington, DC: Environmental Information Coalition, National Council for Science and the Environment, retrieved 2007-12-07 
  3. ^ a b Johnson, L. The Great Bear Lake: Its Place in History. Calgary, Alberta: Arctic Institute of North America (AINA) database at the University of Calgary. pp. 236-237. Retrieved on: 2012-01-30.
  4. ^ "Great Bear Lake". World Lakes Database. International Lake Environment Committee. Retrieved 2 February 2013. 
  5. ^ "Deline - "Where the Water Flows"". Spectacular Northwest Territories. Northwest Territories. Retrieved 2 February 2013. 
  6. ^ "Lake Trout (Salvelinus namaycush)". Fisheries & Aquaculture. Province of Nova Scotia. Retrieved 2 February 2013. 
  7. ^ "Impassable ice roads delay holiday travel". CBC News: North. CBC. 23 December 2009. Retrieved 2 February 2013. 
  8. ^ "Open and Close Dates for the NWT's Community Access Roads". Transportation. Government of the Northwest Territories. Retrieved 2 February 2013. 
  9. ^ Environment Canada Canadian Climate Normals 1961–1990 - Norman Wells. Retrieved 30 January 2012.

External links[edit]