4.
CLIMATE CHANGE AND NATURAL RESOURCE MANAGEMENT: KEY THEMES FROM CASE STUDIES
Table 4.1. GLOFs recorded in Nepal River basin
Name of lake
450 years ago
Seti Khola
Machhapuchhare, Nepal
1935
Sun Koshi
Taraco, Tibet
1964
Arun
Gelaipco, Tibet
1964
Sun Koshi
Zhangzangbo, Tibet
1964
Trishuli
Longda, Tibet
1968
Arun
Ayaco, Tibet
1969
Arun
Ayaco, Tibet
1970
Arun
Ayaco, Tibet Nare, Tibet
1977
Dudh Koshi
1980
Tamur
Nagmapokhari, Nepal
1981
Sun Koshi
Zhangzangbo, Tibet
1982
Arun
Jinco, Tibet
1985
Dudh Koshi
Dig Tsho, Nepal
1991
Tama Koshi
Chubung, Nepal
1998
Dudh Koshi
Sabai Tsho, Nepal
Source: Shrestha and Shrestha (2004).
2 000 m3/sec, two to four times greater than the maximum monsoon flood level. The GLOF destroyed the almost-completed Namche Small Hydro Project, which had cost over USD 1 million. Severe erosion destroyed the weir and head race canal where water would flow into the plant (Raksakulthai, 2003). The damage extended 90 km downstream. Fourteen bridges, including new suspension bridges, were destroyed. Erosion, undercutting and destabilisation occurred on long stretches of the main trail to the Mount Everest base camp. When the trail reopened, prices of staple supplies were 50% higher on average (Ives, 1986). While the loss of human life was limited, it could have been high had the GLOF occurred during peak trekking season. The loss of livelihoods was considerable: vast tracts of arable land were rendered unusable along with critical lifelines such as bridges and roads. An inventory in 2001 found over 3 252 glaciers, 2 323 glacial lakes and 20 potential GLOF sites in Nepal (Mool et al., 2002). In addition to this picture of static risk, site-based monitoring of specific glacial lakes has shown evidence of lake volumes increasing over time. The trend in volume increase correlates well with the observed trends in temperature increase at high altitudes in the Himalayas, discussed earlier. Taken together, the evidence points to a serious hazard closely tied to temperatures rising because of climate change.
2.2. Adaptation options for GLOF risk and stream flow variability Several adaptation strategies are available to cope with GLOF risk and stream flow variability. Some of these responses are already at varying stages
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