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Tsho Rolpa Risk Reduction Project in Nepal as observed anticipatory adaptation The Tsho Rolpa is a...

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Tsho Rolpa Risk Reduction Project in Nepal as observed anticipatory adaptation The Tsho Rolpa is a glacial lake located at an altitude of about 4,580 m in Nepal. Glacier retreat and ice melt as a result of warmer temperature increased the size of the Tsho Rolpa from 0.23 km² in 1957/58 to 1.65 km² in 1997 (Figure 17.1). The 90- 100 million m³ of water, which the lake contained by this time, were only held by a moraine dam – a hazard that called for urgent action to reduce the risk of a catastrophic glacial lake outburst flood (GLOF). If the dam were breached, one third or more of the water could flood downstream. Among other considerations, this posed a major risk to the Khimti hydropower plant, which was under construction downstream. These concerns spurred the Government of Nepal, with the support of international donors, to initiate a project in 1998 to lower the level of the lake through drainage. An expert group recommended that, to reduce the risk of a GLOF, the lake should be lowered three metres by cutting a channel in the moraine. A gate was
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Tsho Rolpa Risk Reduction Project in Nepal as observed anticipatory adaptation

The Tsho Rolpa is a glacial lake located at an altitude of about4,580 m in Nepal. Glacier retreat and ice melt as a result ofwarmer temperature increased the size of the Tsho Rolpa from0.23 km² in 1957/58 to 1.65 km² in 1997 (Figure 17.1). The 90-100 million m³ of water, which the lake contained by this time,were only held by a moraine dam – a hazard that called forurgent action to reduce the risk of a catastrophic glacial lakeoutburst flood (GLOF).

If the dam were breached, one third or more of the water couldflood downstream. Among other considerations, this posed amajor risk to the Khimti hydropower plant, which was underconstruction downstream. These concerns spurred theGovernment of Nepal, with the support of international donors,to initiate a project in 1998 to lower the level of the lake throughdrainage. An expert group recommended that, to reduce therisk of a GLOF, the lake should be lowered three metres bycutting a channel in the moraine. A gate was constructed toallow for controlled release of water. Meanwhile, an earlywarning system was established in 19 villages downstream incase a Tsho Rolpa GLOF should occur despite these efforts.Local villagers were actively involved in the design of thesystem, and drills are carried out periodically. In 2002, the fouryear construction project was completed at a cost of US$3.2million. Clearly, reducing GLOF risks involves substantial costsand is time-consuming as complete prevention of a GLOFwould require further drainage to lower the lake level.

Tsho Rolpa Risk Reduction Project in Nepal as observed anticipatory adaptation

Tsho Rolpa hazard mitigation project site, October 2000

Engineers cut a notch in the moraine that holds back the lake; the notch was dammed and a sluice gate installed to allow controlled release of water.           Sluice gate controlling flow notch cut in moraine bank of lake.

Channel 1Channel 1

Channel 2Channel 2

Channel 3Channel 3

http://rolwaling.tripod.com/2k/2k-tr-fix.html

Mapping vulnerability of the agricultural sector to both climate change and trade liberalization at the district level in India

The capacity to adapt to climate change is not evenly distributed within nations. O’Brien et al. (2004) considered adaptive capacity as a key factor that influences outcomes. Districts in India that rank highest in terms of vulnerability to: (a) climate change and (b) import competition associated with economic globalization, are considered to be double exposed (depicted with hatching).A combination of biophysical, socio-economic and technological conditions were considered to influence the capacity to adapt to changing environmental and economic conditions. The biophysical factors included soil quality and depth, and groundwater availability, whereas socio-economic factors consisted of measures of literacy, gender equity, and the percentage of farmers and agricultural wage laborers in a district. Technological factors were captured by the availability of irrigation and the quality of infrastructure. Together, these factors provide an indication of which districts are most and least able to adapt to drier conditions and variability in the Indian monsoons, as well as to respond to import competition resulting from liberalised agricultural trade. The results of this vulnerability mapping show the districts that have ‘double exposure’ to both processes. It is notable that districts located along the Indo-Gangetic Plains are less vulnerable to both processes, relative to the interior parts of the country.

Geographical distribution of vulnerability in 2050 with and without mitigation along an SRES A2 emissions scenario with a climate sensitivity of 5.5°C.

Geographical distribution of vulnerability in 2100 with and without mitigation along an SRES A2 emissions scenario with a climate sensitivity of 5.5°C.


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