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
Location Northwest Territories
Coordinates 66°N 121°W / 66°N 121°W / 66; -121Coordinates: 66°N 121°W / 66°N 121°W / 66; -121
Primary outflows Great Bear River
Catchment area 114,717 km2 (44,292 sq mi)[1][2]
Basin countries Canada
Surface area 31,153 km2 (12,028 sq mi)[1][2]
Average depth 71.7 m (235 ft)[1][2]
Max. depth 446 m (1,463 ft)[1][2]
Water volume 2,236 km3 (536 cu mi)[1][2]
Residence time 124 years[1]
Shore length1 2,719 km (1,690 mi) (plus 824 km (512 mi) island shoreline)[1][2]
Surface elevation 186 m (610 ft)
Frozen November - July[2]
Islands 26 main islands, totaling 759.3 km2 (293.2 sq mi) in area[1]
Settlements Deline
References [1][2]
1 Shore length is not a well-defined measure.

The Great Bear Lake (Slavey: Sahtú /ˈsɑː.t/, 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] There is an ice crossing from Deline to the winter road on the far side of the Great Bear River.[6][7]

The Sahtu Dene people took their name from the lake.[3]

In 1930, Gilbert LaBine discovered uranium deposits in the Great Bear Lake region. The former mining area Port Radium, site of the Eldorado Mine where pitchblende was discovered, was located on the eastern shore.

Three lodges around the lake are destinations for fishing and hunting.[2] In 1995, a 32.8 kg (72.3 lb) lake trout was caught, the largest ever caught anywhere by angling.[8]

Great Bear Lake. Note the smoke plumes from wildfires

Great Bear Lake is covered with ice from late November to July.[2]

Climate data for Deline Airport
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high Humidex 2.8 0.5 3.8 16.6 22.8 29.8 33.5 31.8 22.9 20.5 2.4 0.3 33.5
Record high °C (°F) 2.5
(36.5)
1.0
(33.8)
4.0
(39.2)
16.0
(60.8)
22.5
(72.5)
29.3
(84.7)
31.0
(87.8)
32.0
(89.6)
23.5
(74.3)
20.8
(69.4)
4.8
(40.6)
3.3
(37.9)
32.0
(89.6)
Average high °C (°F) −20.9
(−5.6)
−18.5
(−1.3)
−13.9
(7)
−1.9
(28.6)
7.4
(45.3)
16.8
(62.2)
19.4
(66.9)
16.6
(61.9)
10.2
(50.4)
−0.8
(30.6)
−11.5
(11.3)
−17.6
(0.3)
−1.2
(29.8)
Daily mean °C (°F) −25.0
(−13)
−23.2
(−9.8)
−19.5
(−3.1)
−7.7
(18.1)
2.5
(36.5)
10.7
(51.3)
13.3
(55.9)
11.2
(52.2)
5.7
(42.3)
−3.9
(25)
−15.4
(4.3)
−22.0
(−7.6)
−6.1
(21)
Average low °C (°F) −28.9
(−20)
−27.8
(−18)
−25.1
(−13.2)
−13.6
(7.5)
−2.5
(27.5)
4.4
(39.9)
7.2
(45)
5.8
(42.4)
1.3
(34.3)
−7.0
(19.4)
−19.2
(−2.6)
−26.3
(−15.3)
−11.0
(12.2)
Record low °C (°F) −49.1
(−56.4)
−43.3
(−45.9)
−43.3
(−45.9)
−35.0
(−31)
−23.3
(−9.9)
−4.0
(24.8)
−1.8
(28.8)
−4.9
(23.2)
−13.3
(8.1)
−29.7
(−21.5)
−37.4
(−35.3)
−43.0
(−45.4)
−49.1
(−56.4)
Wind chill −57.2 −54.0 −55.3 −40.4 −27.6 −6.4 0.0 −3.6 −16.3 −34.4 −46.7 −54.7 −57.2
Precipitation mm (inches) 10.3
(0.406)
11.2
(0.441)
10.3
(0.406)
10.1
(0.398)
14.8
(0.583)
24.3
(0.957)
40.3
(1.587)
43.2
(1.701)
39.5
(1.555)
31.1
(1.224)
21.7
(0.854)
11.9
(0.469)
268.7
(10.579)
Rainfall mm (inches) 0.0
(0)
0.0
(0)
0.0
(0)
0.1
(0.004)
12.2
(0.48)
24.2
(0.953)
40.3
(1.587)
43.2
(1.701)
37.1
(1.461)
4.9
(0.193)
0.4
(0.016)
0.0
(0)
162.3
(6.39)
Snowfall cm (inches) 13.0
(5.12)
16.9
(6.65)
17.1
(6.73)
12.3
(4.84)
3.4
(1.34)
0.2
(0.08)
0.0
(0)
0.0
(0)
2.4
(0.94)
32.2
(12.68)
35.2
(13.86)
17.3
(6.81)
150.0
(59.06)
Avg. precipitation days (≥ 0.2 mm) 5.4 6.8 7.5 3.9 6.1 8.0 10.4 12.3 12.4 12.4 10.1 7.2 102.4
Avg. rainy days (≥ 0.2 mm) 0.0 0.0 0.0 0.2 4.5 8.0 10.4 12.3 11.8 2.4 0.1 0.0 49.7
Avg. snowy days (≥ 0.2 cm) 6.7 7.5 9.4 4.2 1.7 0.1 0.0 0.0 0.9 10.5 11.4 8.9 61.4
 % humidity 74.9 76.1 76.7 75.0 63.0 54.5 58.2 62.1 65.7 82.6 82.5 76.1 70.6
Source: Environment Canada Canadian Climate Normals 1981–2010[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 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 19 August 2014. 
  6. ^ "Impassable ice roads delay holiday travel". CBC News: North. CBC. 23 December 2009. Retrieved 2 February 2013. 
  7. ^ "Open and Close Dates for the NWT's Community Access Roads". Transportation. Government of the Northwest Territories. Retrieved 2 February 2013. 
  8. ^ "Lake Trout (Salvelinus namaycush)". Fisheries & Aquaculture. Province of Nova Scotia. Retrieved 2 February 2013. 
  9. ^ "Deline A" (CSV (3069 KB)). Canadian Climate Normals 1981–2010. Environment Canada. Climate ID: 22010KA. Retrieved 2014-01-09. 

External links[edit]