Stable glacier

Area of ice accumulation

Ice fall Glacier body C M 0 Y CM MY CY CMY K Glacier terminus

Direction of outburst flood (GLOF)

2 km

Glacier surge and formation of ice dam

Glacier lake

Figure 8: Formation of ice dammed lake by an advancing (surging) glacier: Medvezhi Glacier, Pamirs.

ties, because farther downstream the flood peaks are gen- erally within the range of non-catastrophic river discharges (Cenderelli and Wohl, 2003). In the next few decades GLOF impacts will likely extend farther downstream than those experienced to date, as climate changes lead to lake forma- tion on larger high-altitude glaciers. So far GLOFs have been relatively rare events, but there is little doubt that the

potential for more outbursts as well as drastic consequences will increase.

Five major GLOFs also took place in April, October and De- cember 2008, and again in March and September 2009 in the Northern Patagonia Icefield, Chile (Dussaillant et al., 2010). On each event, the Cachet 2 Lake, dammed by the Colonia

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