The Role of Mountain Glaciers and Ice Caps in Sea Level ...
Transcript of The Role of Mountain Glaciers and Ice Caps in Sea Level ...
The Role of Mountain Glaciers and Ice Caps in Sea Level Rise: Past, Present and
Future
Georg Kaser1) and Graham Cogley2)
1)University of Innsbruck, Austria2)Trent University, Peterborough, Ontario, Canada
AAAS * Sea Level Rise * CHICAGO * 090216
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Kibo, EIF, January 2009 (g*kaser)
Mountain Glaciers and Ice Caps
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• How much water is presently released from MG&IC?• How much of it reaches the Ocean?• How much water is stored in MG&IC?
Concept and uncertainties
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Lemke et al. (2007) - IPCC 2007 – AR4 WG I, Ch. 4
The underway loss
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MG&IC excluding those in GL and AA: 0.15 – 0.43 m SLEMG&IC including those in GL and AA: 0.49 – 0.74 m SLE
Lemke et al. (2007) - IPCC 2007 – AR4 WG I, Ch. 4
The total extent of MG&IC
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oInventories
NSI
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htt
p://
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ims/
G. Cogley, unpublished
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-18000
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1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
Hydrological years
Cum
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ChacaltayaZongo
IRD - Great Ice - Bolivia
Francou et al. MRI, 2005
Representativity
Juen Uibk, 2006
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Area-Elevation Distribution (Ötztal Alps)
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0 2 4 6 8 10 12
Area [%]
Elev
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all glaciers Hintereisferner
1997 2003 2004 2005Extrapolation bmean/b(Z) [kg m-2]: 48% 19% 50% 27%
Vertical gradients
Hoinkes, S., in progress
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Melt water from surfaceIce discharge
Meier et al. Science (2007):2006: 1.4 ± 0.24 mm SLE yr-1
Calving glaciers
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Marine calving glaciers: from 3 to 16%Lake calving glaciers: from 4 to 16%
Directly and geodetically measured data
Cogley Ann. Glac., 2009
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Cogley, Ann. Glac. (2009)
1.1 mm SLE yr-1
Directly and geodetically measured data
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oModelling from atmospheric RA
Hock et al. GRL (in press)
1961 – 2004: 0.79 ± 0.34 mm SLE yr-1
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oThe future
Huss et al., Hydr.Process. (2008)
Meier et al. Science (2007): until 2050: 0.040 – 0.124 m SLRuntil 2100: 0.080 – 0.368 m SLR
MG&IC including those in GL and AA: 0.49 – 0.74 m SLELemke et al. (2007) - IPCC 2007 – AR4 WG I, Ch. 4
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oConclusions
• Total:0.49 – 0.74 m SLE• Loss: around 1.1 mm SLE yr-1
• Uncertainties: - lack of data: are & volume- lack f data: mass budgets- extrapolation methods- ice dynamics?