The 2002 Caucasus ice-rock avalanche and its implications
One of the largest historical glacier disasters occurred in 2002 in frost conditions was influenced by deep-seated thermal anoma-
the Russian Republic of North Ossetia in the Caucasus. An ice- lies induced by the overlying ice and firn through processes such
rock avalanche resulting from a slope failure in the Kazbek region as latent heat production from percolating and refreezing melt-
and a connected instability of the Kolka glacier devastated tens water
13
. Increasing air temperatures can cause disturbances in
of kilometres along the length of the Genaldon valley
13,45–47
. The such complex system, which eventually can lead to slope failure.
Kolka ice-rock avalanche (Figure 6B.8) is remarkable for several Similar conditions as in the Caucasus exist in many glacierized
reasons. The steep, high mountain wall of the initial slope failure mountain regions of the world. In more populated areas such
was covered by firn and ice masses, a composition that is inher- as the European Alps, similarly large slope failures would cause
ently unstable. The underlying bedrock in relatively cold perma- catastrophes of even much larger dimensions.
Figure 6B.8: Caucasus ice-rock avalanche in Russian Republic of North Ossetia. An ice-rock avalanche in the Kazbek region sheared
off almost the entire Kolka Glacier and devastated the Genaldon valley. The satellite images show the region before (July 22, 2001)
and after (October 6, 2002) the ice-rock avalanche of September 20, 2002.
Source: The ASTER scenes were provided within the framework of the Global Land Ice Measurements from Space project (GLIMS) through the EROS data
center, and are courtesy of NASA/GSFC/METI/ERSDAC/JAROS and the US/Japan ASTER science team
126 GLOBAL OUTLOOK FOR ICE AND SNOW