Wilfried Haeberli Geography Department University of Zurich
Glacial lakes, emerging risks and water issues
Trift glacier Swiss Alps Alean
New lakes: tourist attraction hydropower potential hazard source water resource conflict area possible synergies
??? Trift glacier Swiss Alps Alean
Glaciers and lakes in Nepal Landsat
Miller glacier New Zealand Chinn
Tasman glacier New Zealand Chinn
Recognizing overdeepenings in glacier beds: potential future glacier lakes I.  Distinct break in slope II.  Reduction of glacier width (narrowing) III.  crevasse-free part is followed by a heavily crevassed part
Frey, H., Haeberli, W., Linsbauer, A., Huggel, C. and Paul, F. (2010): A multi level strategy for anticipating future glacier lake formation and associated hazard potentials. Natural Hazards and Earth System Science 10, 339-352.
Example: Trift glacier 1948 - 2006
Trift glacier Swiss Alps Frey
I. Distinct break in slope 2006
1948
© Gesellschaft für ökologische Forschung
II.
Reduction of glacier width (narrowing)
III. crevasse-free part is followed by a heavily crevassed part
Modelling of possible future lakes
Rhone glacier Swiss Alps Linsbauer, Alean
contour lines (50 m) glacier outlines flowlines surface slope base points interpolated glacier bed
Linsbauer, A., F. Paul, M. Hoelzle, H. Frey and W. Haeberli (2009): The Swiss Alps without glaciers - a GIS-based modelling approach for reconstruction of glacier beds. In: Geomorphometry 2009 Conference Proceedings, Purves, R., Gruber, S., Straumann, R., and Hengl, T. (eds.), University of Zurich, Zurich, 243-247, www.geomorphometry.org
Modelling of possible future lakes
Rhone glacier Swiss Alps Linsbauer, Alean
contour lines (50 m) glacier outlines flowlines surface slope base points interpolated glacier bed
Linsbauer, A., F. Paul, M. Hoelzle, H. Frey and W. Haeberli (2009): The Swiss Alps without glaciers - a GIS-based modelling approach for reconstruction of glacier beds. In: Geomorphometry 2009 Conference Proceedings, Purves, R., Gruber, S., Straumann, R., and Hengl, T. (eds.), University of Zurich, Zurich, 243-247, www.geomorphometry.org
Modelling of possible future lakes
Rhone glacier Swiss Alps Linsbauer, Alean
contour lines (50 m) glacier outlines flowlines surface slope base points interpolated glacier bed
Linsbauer, A., F. Paul, M. Hoelzle, H. Frey and W. Haeberli (2009): The Swiss Alps without glaciers - a GIS-based modelling approach for reconstruction of glacier beds. In: Geomorphometry 2009 Conference Proceedings, Purves, R., Gruber, S., Straumann, R., and Hengl, T. (eds.), University of Zurich, Zurich, 243-247, www.geomorphometry.org
Modelling of possible future lakes
Rhone glacier Swiss Alps Linsbauer, Alean
contour lines (50 m) glacier outlines flowlines surface slope base points interpolated glacier bed
Linsbauer, A., F. Paul, M. Hoelzle, H. Frey and W. Haeberli (2009): The Swiss Alps without glaciers - a GIS-based modelling approach for reconstruction of glacier beds. In: Geomorphometry 2009 Conference Proceedings, Purves, R., Gruber, S., Straumann, R., and Hengl, T. (eds.), University of Zurich, Zurich, 243-247, www.geomorphometry.org
Modelling of possible future lakes
Rhone glacier Swiss Alps Linsbauer, Alean
contour lines (50 m) glacier outlines flowlines surface slope base points interpolated glacier bed
Linsbauer, A., F. Paul, M. Hoelzle, H. Frey and W. Haeberli (2009): The Swiss Alps without glaciers - a GIS-based modelling approach for reconstruction of glacier beds. In: Geomorphometry 2009 Conference Proceedings, Purves, R., Gruber, S., Straumann, R., and Hengl, T. (eds.), University of Zurich, Zurich, 243-247, www.geomorphometry.org
Scenario of glacier retreat and lake formation Swiss Alps (Aletsch) Assumption: temperature increase 4째C by 2100, time steps 15 years Linsbauer
Glaciers and permafrost in the Alps ice volume km3 80
PermaNET
25
Ice volume in pe
rmafrost
time 2010
2050?
Aletsch region Swiss Alps
Schaub
Glaciers, new lakes, permafrost and steep, destabilizing mountain flanks in the Alps
Corbassière glacier Swiss Alps
Hydropower and flood protection
Terrier
Terrier Künzler
seasons
P cold Q
Q P warm
Alps/Cordilleras: precipitation, mass balance storage and runoff
seasons
P dry Q
Q
wet
Kaser/Osmaston
P
vanishing surface ice
permafrost degradation slope instability
disappearing support of steep glacier parts, ice avalanches from steep hanging glaciers
de-buttressing of lateral rock slopes Milhuacocha Cordillera Blanca Hegglin
ice avalanches and rock falls not on glacier tongue any more but directly into lake
oversteepened inside slope of lateral moraine
lake formation
Haeberli, W., Clague, J.J., Huggel, C. and Kääb, A. (2010): Hazards from lakes in high-mountain glacier and permafrost regions: Climate change effects and process interactions. Avances de la Geomorphología en España, 2008-2010, XI Reunión Nacional de Geomorphología, Solsona, 439-446.
Lessons learned from the Hualcรกn case
12.04.2010
Nevado Hualcรกn Cordillera Blanca Portocarrero
Pampa de Jonquil Cordillera Blanca
Río Chucchún Cordillera Blanca
río Chucchún
Conclusions Hualcán: • Succesfull hazard prevention: many lives saved • Efficient risk reduction but not to zero • Shift of hazard source to summit areas: polythermal (?) hanging glaciers and warm permafrost • Larger events (106 m3) and new lakes possible, hence further measures necessary • Observation of starting zone important (stabilisation/destabilisation?) • Enhancement of freeboard (deeper tunnel, breach closure) • Retention at Pampa de Shonquil (multipurpose structure) • Passive measures in town (EWS, escape information)
Palcacocha, Peru HualcĂĄn-Carhuaz Cordillera Blanca Schneider
Modeling the process chain and installation of an early warning system ‌
Lake probably shallow Lake probably deep Lake formation uncertain Lake formation ongoing or imminent Lake formation in coming decades
Hualcรกn-Carhuaz Cordillera Blanca possible retention
New lakes: model chain for scenario development and hazard assessment spatial models of climate/glacier scenarios spatial model of ice thickness
digital terrain model without glaciers spatial model of new lakes
spatial models of potential rock, ice and rock/ice avalanches into lakes spatial models of potential floods and debris flows from new lakes
Create a knowledge basis for future generations what do we expect? what can we do? how should we proceed?
Gruben glacier Swiss Alps