Variability in ice phenology on Great Bear Lake and Great Slave Lake, Northwest Territories, Canada, from SeaWinds/QuikSCAT: 2000–2006

We document the first occurrence of Pygmy Whitefish (Prosopium coulterii) in the Northwest Territories outside of Great Bear Lake. Six specimens were captured in Bluefish Lake in September 2012. Bluefish Lake is on the Yellowknife River, approximately 25 km upstream from Great Slave Lake.

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Great Slave Lake to Great Bear Lake, District of Mackenzie, Northwest Territories

10.4095/108229 ◽

1941 ◽

Author(s):

Keyword(s):

Northwest Territories ◽

Lake District ◽

Bear Lake ◽

Great Slave Lake

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Estimating ice phenology on large northern lakes from AMSR-E: algorithm development and application to Great Bear Lake and Great Slave Lake, Canada

The Cryosphere Discussions ◽

10.5194/tcd-5-3129-2011 ◽

2011 ◽

Vol 5 (6) ◽

pp. 3129-3173

Author(s):

K.-K. Kang ◽

C. R. Duguay ◽

S. E. L. Howell

Keyword(s):

Ice Cover ◽

Brightness Temperatures ◽

Earth Observing System ◽

Bear Lake ◽

Great Slave Lake ◽

Mapping System ◽

Coarse Spatial Resolution ◽

Spatio Temporal ◽

Melt Duration ◽

Ice Phenology

Abstract. Time series of brightness temperatures (TB) from the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) are examined to determine ice phenological parameters on the two largest lakes of northern Canada: Great Bear Lake (GBL) and Great Slave Lake (GSL). TB measurements from the 18.7, 23.8, 36.5, and 89.0 GHz channels (H- and V- polarization) are compared to assess their potential for detecting freeze-onset/melt-onset and ice-on/ice-off dates on both lakes. The 18.7 GHz (H-pol) channel is found to be the most suitable for estimating these ice dates as well as the duration of the ice cover and ice-free seasons. A new algorithm is proposed using this channel and applied to map all ice phenological parameters on GBL and GSL over seven ice seasons (2002–2009). Analysis of the spatio-temporal patterns of each parameter at the pixel level reveals that: (1) both freeze-onset and ice-on dates occur on average about one week earlier on GBL than on GSL (Day of Year (DY) 318 and 333 for GBL; DY 328 and 343 for GSL); (2) the freeze-up process or freeze duration (freeze-onset to ice-on) takes a slightly longer amount of time on GBL than on GSL (about 1 week on average); (3) melt-onset and ice-off dates occur on average one week and approximately four weeks later, respectively, on GBL (DY 143 and 183 for GBL; DY 135 and 157 for GSL); (4) the break-up process or melt duration (melt-onset to ice-off) lasts on average about three weeks longer on GBL; and (5) ice cover duration estimated from each individual pixel is on average about three weeks longer on GBL compared to its more southern counterpart, GSL. A cross-comparison of dates for several ice phenological parameters derived from other satellite remote sensing products (e.g. NOAA Interactive Multisensor Snow and Ice Mapping System (IMS), QuikSCAT, and Canadian Ice Service Database) show that, despite its relatively coarse spatial resolution, AMSR-E 18.7 GHz provides a viable means for monitoring of ice phenology on large northern lakes.

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Estimating ice phenology on large northern lakes from AMSR-E: algorithm development and application to Great Bear Lake and Great Slave Lake, Canada

The Cryosphere ◽

10.5194/tc-6-235-2012 ◽

2012 ◽

Vol 6 (2) ◽

pp. 235-254 ◽

Cited By ~ 26

Author(s):

K.-K. Kang ◽

C. R. Duguay ◽

S. E. L. Howell

Keyword(s):

Ice Cover ◽

Brightness Temperatures ◽

Earth Observing System ◽

Bear Lake ◽

Great Slave Lake ◽

Mapping System ◽

Coarse Spatial Resolution ◽

Spatio Temporal ◽

Melt Duration ◽

Ice Phenology

Abstract. Time series of brightness temperatures (TB) from the Advanced Microwave Scanning Radiometer–Earth Observing System (AMSR-E) are examined to determine ice phenology variables on the two largest lakes of northern Canada: Great Bear Lake (GBL) and Great Slave Lake (GSL). TB measurements from the 18.7, 23.8, 36.5, and 89.0 GHz channels (H- and V- polarization) are compared to assess their potential for detecting freeze-onset/melt-onset and ice-on/ice-off dates on both lakes. The 18.7 GHz (H-pol) channel is found to be the most suitable for estimating these ice dates as well as the duration of the ice cover and ice-free seasons. A new algorithm is proposed using this channel and applied to map all ice phenology variables on GBL and GSL over seven ice seasons (2002–2009). Analysis of the spatio-temporal patterns of each variable at the pixel level reveals that: (1) both freeze-onset and ice-on dates occur on average about one week earlier on GBL than on GSL (Day of Year (DY) 318 and 333 for GBL; DY 328 and 343 for GSL); (2) the freeze-up process or freeze duration (freeze-onset to ice-on) takes a slightly longer amount of time on GBL than on GSL (about 1 week on average); (3) melt-onset and ice-off dates occur on average one week and approximately four weeks later, respectively, on GBL (DY 143 and 183 for GBL; DY 135 and 157 for GSL); (4) the break-up process or melt duration (melt-onset to ice-off) lasts on average about three weeks longer on GBL; and (5) ice cover duration estimated from each individual pixel is on average about three weeks longer on GBL compared to its more southern counterpart, GSL. A comparison of dates for several ice phenology variables derived from other satellite remote sensing products (e.g. NOAA Interactive Multisensor Snow and Ice Mapping System (IMS), QuikSCAT, and Canadian Ice Service Database) show that, despite its relatively coarse spatial resolution, AMSR-E 18.7 GHz provides a viable means for monitoring of ice phenology on large northern lakes.

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Simulation of ice phenology on Great Slave Lake, Northwest Territories, Canada

Hydrological Processes ◽

10.1002/hyp.1230 ◽

2002 ◽

Vol 16 (18) ◽

pp. 3691-3706 ◽

Cited By ~ 47

Author(s):

Patrick Ménard ◽

Claude R. Duguay ◽

Greg M. Flato ◽

Wayne R. Rouse

Keyword(s):

Northwest Territories ◽

Great Slave Lake ◽

Ice Phenology

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Carbon Fixation Trends in Eleven of the World’s Largest Lakes: 2003–2018

Water ◽

10.3390/w12123500 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3500

Author(s):

Michael Sayers ◽

Karl Bosse ◽

Gary Fahnenstiel ◽

Robert Shuchman

Keyword(s):

Climate Change ◽

Primary Production ◽

Great Lakes ◽

Satellite Remote Sensing ◽

Carbon Fixation ◽

African Great Lakes ◽

Wind Speeds ◽

Bear Lake ◽

Great Slave Lake ◽

Significant Production

Large freshwater lakes provide immense value to the surrounding populations, yet there is limited understanding of how these lakes will respond to climate change and other factors. This study uses satellite remote sensing to estimate annual, lake-wide primary production in 11 of the world’s largest lakes from 2003–2018. These lakes include the five Laurentian Great Lakes, the three African Great Lakes, Lake Baikal, and Great Bear and Great Slave Lakes. Mean annual production in these lakes ranged from under 200 mgC/m2/day to over 1100 mgC/m2/day, and the lakes were placed into one of three distinct groups (oligotrophic, mesotrophic, or eutrophic) based on their level of production. The analysis revealed only three lakes with significant production trends over the study period, with increases in Great Bear Lake (24% increase over the study period) and Great Slave Lake (27%) and a decline in Lake Tanganyika (−16%). These changes appear to be related to climate change, including increasing temperatures and solar radiation and decreasing wind speeds. This study is the first to use consistent methodology to study primary production in the world’s largest lakes, allowing for these novel between-lake comparisons and assessment of inter-annual trends.

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Fecundity Comparisons for Various Stocks of Lake Whitefish, Coregonus clupeaformis

Journal of the Fisheries Research Board of Canada ◽

10.1139/f75-048 ◽

1975 ◽

Vol 32 (3) ◽

pp. 404-407 ◽

Cited By ~ 7

Author(s):

M. C. Healey ◽

C. W. Nicol

Keyword(s):

Northwest Territories ◽

Lake Erie ◽

Fork Length ◽

Nonlinear Relationship ◽

Coregonus Clupeaformis ◽

Lake Whitefish ◽

Limited Data ◽

Relative Fecundity ◽

Great Slave Lake ◽

The Relationship

We found no significant differences in slope or intercept for the regression of loge fecundity on loge fork length among samples of whitefish from four lakes near Yellowknife in the Northwest Territories. The equation describing the relationship between fecundity and fork length for these populations was:[Formula: see text]Five other populations for which length–fecundity relationships could be calculated had length exponents ranging from 3.20 to 4.38, suggesting a nonlinear relationship between weight and fecundity. Six of the nine populations as well as four others for which limited data were available all had similar relative fecundities. Fish from Buck Lake in Alberta and from Lake Erie had high relative fecundities while fish from Great Slave Lake had low relative fecundity.

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Angling License Sales from Northwest Territories, Canada, with Special Reference to Great Slave Lake

Journal of the Fisheries Research Board of Canada ◽

10.1139/f64-054 ◽

1964 ◽

Vol 21 (3) ◽

pp. 643-645

Author(s):

J. J. Keleher

Keyword(s):

Special Reference ◽

Northwest Territories ◽

Great Slave Lake

not available

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Pseudoditrichum mirabile gen. et sp. nov. (Musci: Pseudoditrichaceae fam. nov.), a unique moss from Great Bear Lake, Northwest Territories

Canadian Journal of Botany ◽

10.1139/b74-090 ◽

1974 ◽

Vol 52 (4) ◽

pp. 701-705 ◽

Cited By ~ 5

Author(s):

William Campbell Steere ◽

Zennoske Iwatsuki

Keyword(s):

Northwest Territories ◽

New Genus ◽

The Arctic ◽

Phylogenetic Position ◽

New Genus And Species ◽

Arctic Circle ◽

New Family ◽

Bear Lake ◽

Evolutionary Level

The name Pseudoditrichum mirabile Steere et Iwatsuki is proposed for a minute moss with leafy stem 1-3 mm high and seta 6 mm long; it was collected on calcareous silt near the Sloan River, Great Bear Lake, Northwest Territories, only a few miles south of the Arctic Circle. The gametophytic characters agree well with those of the Ditrichaceae, a relatively primitive family, but the peristome is clearly double, with the inner and outer teeth opposite, which thereby indicates a much more advanced phylogenetic position, perhaps at the evolutionary level of the Funariaceae. As the combination of gametophytic and sporophytic characteristics exhibited by this moss does not occur in any existing family of mosses, it is therefore deemed necessary to create the new family Pseudoditrichaceae for the new genus and species described here.

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