Glacier change modelling in the tropics
Georg Kaser INARCH Kananaskis ‐ 24. Oktober 2015
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http://www.imaggeo.net/view/142
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Climate → glacier
Climate
Equilibrium Line Altitude ELA
Mass & Energy
Mass
change
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Glaciers are …
… machines that turn weather into climate signals
… low pass filters, „but these filters come without a manual“
B. Marzeion (Marzeion et al, TC 2012)
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Climate│Glacier: processes
sublimation, melt
energy balance
SW
SW LW
+
-
GLACIER
snowfall
LW
+
-
QS, QL
+/-
+/QG
SNOW
(20-30 levels)
energy fluxes
mass fluxes
©Mölg
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Glacier ‐ atmosphere
large scale drivers
meso scale
conditions
micro scale processes
Kibo, SIF, AWS3 (5850 m asl), 2007
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Kibo
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Glacier ‐ atmosphere
26–29 July 2005
Kibo, NIF AWS1, 2005
Modelled turbulent fluxes (bulk method) compared well to eddy covariance data. Modelled sublimation accounted for about 90% of observed ablation
Cullen et al, AnnGlac (2007)
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Glacier ‐ Atmosphere
ATMOSPHERE
GCM
downscaling
downscaling
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Regional circulation
Mölg et al., QJRMS (2009)
Cloud mixing ratio with (left) WET and (right) DRY forcing
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Dynamical „downscaling“ mass budget (kg m2)
40
wet (April 2006)
20
AWS forcing
LAM forcing
0
-20
dry (August 2005)
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0
100
200
300
400
hour of month
500
600
700
Mölg und Kaser JGR (2011)
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Partitioning the contributors to MB
Mölg et al., TC (2012)
Zhadang Glacier (central Tibet, 30° N)
Monsoon onset
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Glaciers as climate‐meters
NAO
+ Alps
ENSO
Asian Monsoon
Mt. Kenya
Rwenzori + +
+ Cordillera Blanca
+
Kilimanjaro
Irian Jaya +
IOZM
ENSO
ENSO
hygric seasonality – circulation patterns (modes)
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Observes sea level rise 1993‐2010: 3.2 mm/year
Thermal expansion: 38%
Glaciers:
28%
Greenl. Ice Sheet: 10%
Antarct. Ice Sheet: 10%
Land water stor.:
14%
Total :
Obs. GMSLR: Data from Table 13.1
Distributed MB modeling
IPCC AR5 WG1 Ch.13 (2013)
100%
110% 14/41
Glaciar Shallap, Cordillera Blanca
SH11
SH22
Gurgiser et al. TC (2013)
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Glaciar Shallap
Distributed MB modeling
Gurgiser et al. TC 2013
Daily snow fall and disaperance
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Glaciar Shallap
Point comparison
Gurgiser et al. JoG (2013)
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Back to the „Lab “: Hintereisferner
1880s
Stream lines
layers
acc. abl.
Blümcke, A. and H. Hess (1899)
Finsterwalder (1897)
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Seasonal mass balance and ENSO
Maussion et al. TCD (2015)
regression‐based downscaling model that links the local SEB/SMB fluxes to atmospheric reanalysis variables on a monthly basis
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