ENSC454 Snow and Ice: Glaciers April Roger Wheate (NRES)

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1 ENSC454 Snow and Ice: Glaciers April Roger Wheate (NRES) Roger.Wheate@unbc.ca Sólheimajökull, Iceland The main purpose of snow: it makes glaciers

2 April 1 other uses of snow

3 April 1 uses of glaciers: meltwater stream (Castle Creek)

4 April 1 other uses of glaciers this water comes from melted glacial ice 200 miles north of Vancouver and 36 miles east into the Toba Inlet. $155 per case of 12 bottles (750ml) Per 750ml bottle: USD$12.92 (~S$18); up to USD$45.83 (~S$62)

5 April 1 other uses of glaciers This photo of the iceberg that sank the Titanic was taken by the chief steward of the German ocean liner SS Prinz Adalbert just hours after the tragedy. Its identity was confirmed by a red streak of paintwork scraped across its base, an indication that it had collided with a vessel in the past 12 hours or so

6 Reasons to study glaciers Because they are there (and cool).. They last longer than snow Impact on river temperature Water supply for hydro power Water supply to agriculture Hazards e.g. outburst floods The canary of climate change Impact on sea level rise They are usually remote > remote sensing

7 ENSC454 Snow and Ice: Remote sensing of Glaciers Introduction Ice ages and change Types of Glaciers Distribution of glaciers Glacier change and remote sensing (Not a glacier)

8 1909 last year of permanent snow on Ben Nevis, Scotland

9 Scottish cirques (corries) inspired Louis Agassiz on glacier theories, 1840

10 Pleistocene maximum ice extent

11 Glaciers in Canada 15,000 years ago - requires cold/cool summer temperatures and high winter precipitation as snow Christopherson (2006)

12 Glaciers need cold and snow Antarctica Dry Valley

13 Global temperatures and glaciers Glaciers reached a post-glacial maximum in the Little Ice Age (ending ~1850)

14 Glaciers need cold and snow

15 Brenndalsbreen, Norway 1743 Early record of glacier change (advance)- overrunning of farm at Tungøyane

16 Robson Glacier Little Ice Age (LIA) extents

17 Castle Glacier, near McBride

18 Icefields Parkway, 1981 Icefields Centre is located on the terminal moraine, Little Ice Age maximum ~1850

19 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. [typical downhill movement is ~1 metre per day in summer] Minimum glacier size : sq km? = 1 5 hectares

20 Non-formation of glaciers: Late summer snow patches Few new glaciers are forming!

21 Post eruption - Glacier forming ~ 2000

22 Types of glaciers Ice sheets Greenland, Antarctica Mountain Icefields Valley (Alpine) Piedmont Cirque Hanging Tidewater Niche Glacierets Hardanger-jokull, Norway Landsat image 1997

23 Hardangerjokull and Finse

24 Valley and hanging glaciers

25 Somewhere in Greenland cirque, valley and tidewater glaciers

26 Elephantfoot glacier, Greenland - piedmont glacier

27 Amethyst Lakes, Jasper National Park Cirque glaciers will be more common on NE aspects

28 Corrie glaciers How small can a glacier be? Minimum sq km? Niche glaciers protected gullies

29 Separated glaciers- new niche glaciers

30 Global Distribution of glaciers Polar (cold), temperate and tropical

31 Distribution of Mountain Glaciers on Earth Zuo and Oerlemans (1997)

32 New Guinea, 1936

33 New Guinea, 1972

34 Kilimanjaro: 1993 and 2000 ice predicted in 2004 to disappear by 2010 (recalculated to 2020) Glacier status depends on: a. (winter) Precipitation b. (summer) Temperature

35 The glacier on Chacaltaya was Bolivia's only ski resort. It is the world's highest lift-served ski area, at 5421m (17,785 feet) and the world's most equatorial Last piece melted 2009

36 National Atlas of Canada (online) archives, 5 th edition

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38 2010 TM543 composite Snow and Ice: High visible reflection Very low in Mid-IR

39 TM 3/5 ratio (red/near IR) Threshold TM 3/5 > 2 TM 3/5 > 2 AND TM4> 30 SIEVE filter with threshold = 30 (pixels)

40 2010 Glaciers/snow polygons (yellow)

41 T. Bolch, B.Menounos, R. Wheate Glacier Change in Area (km²) -285 km² (~ ) -824 km² km² km² km² km² -235 km² km² -342 km² km²

42 Glacier Retreat Rates (% a -1 ) ± 0.15 (~ ) ± ± ± 0.15 Alberta: ± 0.17 BC: ± ± ± ± ± ± ± 0.24 Glacier Changes Whole Inventory: ± 0.16 T. Bolch, B.Menounos, R. Wheate

43 Icy Bay / Malaspina Glacier, Alaska: georeferenced JPG Sept 1984

44 Icy Bay / Malaspina Glacier, Alaska Sept 2010

45 Columbia Ice Field (July.7/1986) Dome Glacier Athabasca Glacier Columbia Glacier Saskatchewan Glacier Columbia Icefield 52 08'N117 18W

46 Columbia Ice Field (July.9/2009) 52 08'N117 18'W

47 Scud Glacier (2002)

48 0.5 km Scud Glacier (2003)

49 Glacier downwasting and retreat Anticipated contribution to sea level rise by 2100: 0.6 metres

50 Athabasca Glacier

51 Andrei Glacier: CanVec (NTDB) DEM 1965 (from contours)

52 BC provincial TRIM mapping 1982

53 Shuttle Radar Topography Mission (SRTM) 1999

54 ASTER GDEM 2004

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56 Salmon Glacier area Alaska / BC

57 Ice on Mars polar caps

58 Matt Beedle s glacier website GEOG432: Remote sensing (fall) Late August-early September: trip to Castle Creek Glacier -> Not a UNBC field trip

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