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Snow and Ice: Glaciers
Reasons to study glaciers
• Because they are there .. … and in the course outline• Impact on river temperature• Water supply for hydro power• Water supply to agriculture • Hazards e.g. outburst floods
• The ‘canary’ of climate change• They last longer than snow
• Can also be used to milk those who can’t turn on a tap ->
ENSC454 Snow and Ice: Glaciers
Glacier formation
Types of Glaciers
Distribution of glaciers
Glacier movement and change
(Not a glacier)
Glacier tour - web resources
Non-formation of glaciers: Late summer snow patches
Snow must safely survive through the year
And not just one year
Mt. St. Helens 2002
What is a glacier ?
A glacier is a long-lasting body of ice that is formed on land and moves in response to gravity and undergoes internal deformation
A glacier is a body of ice, consisting of
recrystallized snow, that shows evidence of downslope or outward movement due to the pull of gravity.
A general measure of downhill movement is 1 metre per day in summer
• How small can a glacier be ?• Minimum .01 - .05 sq km ?
How glaciers form
• Snowflakes collect or accumulate
• More snow falls, compressing it, increasing the density, until after years snow becomes compact and rounded to form firn.
• With more snowfalls, the weight compresses the firn into solid ice of a much greater density.
• If the ice does not melt and snow continues to fall, the ice mass will increase. Gravity causes the ice mass to move downhill.
• As the glacier moves it erodes the landscape on either side and below
• Cirque glacier: :/ http://www.fettes.com/Cairngorms/corrie%20formation.htmp /www.fettes.com/Cairngorms/corrie%20formation.htm
Pure Ice: 917
Glacier ice: 830-910
Firn: 400-830
Fresh snow: 50-200
http://www.sciencelearn.org.nz/contexts/icy_ecosystems/sci_media/animations_and_interactives/snow_to_ice_animation
Snow to ice: Density of snow and ice - kg / m3 (Patterson, 1994)
2. Distribution of glaciers
Zuo and Oerlemans (1997)
Distribution of Mountain Glaciers on Earth
Kilimanjaro: 1993 and 2000
ice predicted in 2004 to disappear by 2010
(recalculated to 2020)
Glacier status depends on:
a. (winter) Precipitationb. (summer) Temperature
15,000 years agoChristopherson (2006)
Glaciers in Canada ….When Ice was King
Antarctica Dry Valley
Distribution of glaciers
There is ice on Mars
National Atlas of Canada (online) archives, 5th edition
http://atlas.nrcan.gc.ca/site/english/maps/freshwater/distribution/glaciers/1
BC parks with glaciers [Total 83 parks: 7000 sq km- 1987] Number Glaciers
Ice area (sq. km)
Park area (sq. km) % ice
Tatshenshini-Alsek Park 446 3527.02 9473.24 37.23
Atlin Park 43 621.94 2070.27 30.04
Huchsduwachsdu Nuyem Jees / Kitlope 318 410.38 3211.36 12.78
Ts'yl-Os (Ts'il?os) Park 212 315.42 2358.80 13.37
Garibaldi Park 86 297.41 1887.06 15.76
Wells Gray Park 128 201.69 5407.08 3.73
Atlin Recreation Area 44 127.76 403.89 31.63
Kakwa Park 56 124.77 1708.93 7.30
Cariboo Mountains Park 66 115.05 1133.63 10.15
Mount Robson Park 61 114.24 2253.14 5.07
Kwadacha Wilderness Park 32 107.39 1303.35 8.24
Mount Edziza Park 15 75.79 2659.18 2.85
Tweedsmuir Park (South) 32 70.84 5418.00 1.31
Northern Rocky Mountains Park 79 70.64 6663.83 1.06
Clendinning Park 34 69.39 303.52 22.86
Tweedsmuir Park (North) 58 53.48 4460.96 1.20
Redfern-Keily Park 24 43.31 808.00 5.36
Gitnadoiks River Park 28 41.66 577.44 7.22
Purcell Wilderness Conservancy Park 27 37.18 2009.20 1.85
Monkman Park 17 35.38 628.96 5.62
BC parks with glaciers (.. remaining parks with > 10 sq km glaciers)
K'ootz//khutze Conservancy 29 34.73 341.94 10.16
Foch-Gilttoyees Park 38 33.20 612.16 5.42
Bishop River Park 18 30.65 198.39 15.45
Hamber Park 20 30.37 251.55 12.07
Bugaboo Park 15 29.01 138.17 21.00
Stein Valley Nlaka'pamux Heritage Park 24 26.55 1084.35 2.45
Fiordland Conservancy 45 23.89 844.76 2.83
Great Glacier Park 2 23.34 93.14 25.06
Lava Forks Park 13 23.07 73.88 31.22
Khutzeymateen Park 14 22.23 450.80 4.93
Smokehouse Creek Conservancy 14 20.38 379.02 5.38
Strathcona Park 50 18.97 2470.28 0.77
Upper Lillooet Park 14 18.66 199.96 9.33
Seven Sisters Park 7 18.35 271.40 6.76
Goat Range Park 22 16.57 787.72 2.10
Height of the Rockies Park 22 10.94 541.90 2.02
Bowron Lakes Park 14 10.74 1397.70 0.77
Tantalus Park 10 10.70 113.60 9.42
Spruce Lake Protected Area 33 10.32 712.74 1.45
Golden Ears Park 18 10.17 616.34 1.65
Park name # Glaciers Ice area (1987) Park area % ice
BC parks with glaciers (3) Glaciers Glacier area Total Area %
(1987)Stagoo 8 9.63 114.33 8.42
Gladys Lake Ecological Reserve 8 9.39 430.67 2.18
Upper Seymour River Park 6 8.91 106.76 8.35
Elk Lakes Park 14 8.40 180.13 4.66
Ningunsaw Park 12 8.25 157.19 5.25
Tatlatui Park 12 6.40 1032.36 0.62
Goosegrass Creek Ecological Reserve 1 6.12 27.01 22.67
Small River Caves Park 2 5.91 18.10 32.66
Finlay Russel Park 6 4.89 1092.27 0.45
Spatsizi Plateau Wilderness Park 7 4.85 7000.75 0.07
Swan Lake Kispiox River Park 6 3.88 623.03 0.62
Joffre Lakes Park 3 3.81 14.88 25.60
Pinecone Burke Park 5 3.78 372.53 1.02
Kokanee Glacier Park 3 3.78 319.05 1.19
Woss Lake Park 3 3.73 65.27 5.72
Cummins Lakes Park 5 3.46 218.27 1.59
Crab Lake Conservancy 4 2.83 127.99 2.21
Dune Za Keyih Park 7 2.78 3317.30 0.08
Anhluut'ukwsim Laxmihl Angwinga'Asanskwhl Nisgaa 4 2.75 178.80 1.54
Q'altanaas/Aaltanhash Conservancy 6 2.56 187.84 1.36
Hunwadi/Ainuhhati-Bald Peak Conservancy 4 2.46 345.28 0.71
Big Creek Park 6 2.08 679.62 0.31
BC parks with glaciers (4) Glaciers Glacier area Total Area %
(1987)
Gingietl Creek Ecological Reserve 3 1.75 29.00 6.05
Bear Glacier Park 1 1.52 5.81 26.12
Mehatl Creek Park 6 1.11 238.93 0.46
Wapiti Lake Park 2 1.09 168.37 0.64
Ptarmigan Creek Park 2 1.01 33.06 3.07
Valhalla Park 2 0.92 500.32 0.18
Upper Raush Protected Area 3 0.91 55.80 1.63
West Twin Park 1 0.89 223.20 0.40
Schoen Lake Park 1 0.65 87.79 0.74
Callaghan Lake Park 2 0.65 26.93 2.40
Blackcomb Glacier Park 2 0.60 2.44 24.38
Denetiah Park 1 0.59 904.63 0.07
Dunn Peak Park 3 0.41 195.67 0.21
Skagit Valley Park 1 0.39 279.71 0.14
Babine Mountains Park 1 0.38 314.77 0.12
Monashee Park 2 0.38 226.63 0.17
Sikanni Chief River Ecological Reserve 1 0.34 21.76 1.54
Strathcona-Westmin Park 1 0.25 30.86 0.81
Birkenhead Lake Park 1 0.15 97.77 0.15
Duffey Lake Park 1 0.08 20.97 0.36
Sustut Park 1 0.03 756.87 0.00
Mountain glaciers in the cryosphereMountain glaciers in the cryosphere
• Small area and volume compared to ice sheets
• Total sea level rise equivalent: “only” 0.5 m
• + close to human activities
0.3 km
4 km
Surface (106 km2)
Volume (106 km3)
Sea level equivalent
(m)
Antarctica 12.1 29 68
Greenland 1.71 2.95 7.4
Mountain Glaciers
0.68 0.18 0.5
Sea Ice 16 to 25 0
Permafrost 22.7 ? ?
Continental Snow
1 to 50 x x
Surface and volume of different components of the cryosphere (IPCC, 2001)
(E. Berthier)
Types of glaciers• Ice sheets – Greenland, Antarctica• Mountain (Icefields)• Valley (Alpine)• Piedmont• Cirque• Hanging• Tidewater• Niche• Glacierets
http://www.solcomhouse.com/icecap.htm
Niche glaciers
How small can a glacier be ?Minimum .01 - .05 sq km ?
Valley and hanging glaciers
Separated glaciers
Change and movement: Pleistocene maximum ice extent
… somewhere between PG and Vancouver
Nigardsbreen, Norway
Crevasses and surge moraine
Glacier energy and budget: Corrie (cirque) formation
Organisation of a mountain glacierOrganisation of a mountain glacier
Zones
Mass balance
Accumulation zone ~ (winter) PrecipitationAblation zone ~ (summer) Temperature
Longitudinal profile of a mountain glacier
accumulationEquilibrium line
ablation
moraine
(E. Berthier)
Amethyst Lakes, Jasper Nat Park
Cirque glaciers will be more common on NE aspects
Tropical glaciers: Venezuela: cirque glaciers >4500 metres ASL
New Guinea, 1936
New Guinea, 1972
Hardangerjokull,
Norway
Landsat image 1997
snow is in the way!
Hardangerjokull and Finse
Finse 3 hours ago
Some Glacier websites
http://ebeltz.net/glaciers.html http://www.solcomhouse.com/icecap.htm
http://gallery.backcountry.net/papabear_torngats_maps
http://www.pbs.org/wgbh/nova/sciencenow/3210/03-spac-nf.html
http://www.hi.is/~oi/icelandic_glaciers.htm
Kristie Glacier, near McBride
Castle Glacier, near McBride
Castle Glacier