Nevertheless, experts say money is needed urgently to carry out similar work on scores of other glacial lakes if catastrophes are to be averted. "Part of our work is to help the governments of Nepal and Bhutan find and focus on potentially dangerous lakes, develop early warning systems, be able to warn communities of an impending Glacial Lake Outburst Flood (GLOF), and to carry out engineering works to reduce the threats. Some donor country governments are backing our efforts but much more aid is needed. Solving this problem is going to be costly because glacial lakes are situated in remote areas which are difficult to reach," said Mr Shrestha. Surendra Shrestha, Regional Coordinator in Asia for UNEP's Division of Early Warning and Assessment, said: "Our findings indicate that 20 glacial lakes in Nepal and 24 in Bhutan have become potentially dangerous as a result of climate change. We have evidence that anyone of these could, unless urgent action is taken, burst its banks in five to 10 years time with potentially catastrophic results for people and property hundreds of kilometres downstream. These are the ones we know about. Who knows how many others, elsewhere in the Himalayas and across the world, are in a similar critical state?" Nevertheless, experts say money is needed urgently to carry out similar work on scores of other glacial lakes if catastrophes are to be averted. "Part of our work is to help the governments of Nepal and Bhutan find and focus on potentially dangerous lakes, develop early warning systems, be able to warn communities of an impending Glacial Lake Outburst Flood (GLOF), and to carry out engineering works to reduce the threats. Some donor country governments are backing our efforts but much more aid is needed. Solving this problem is going to be costly because glacial lakes are situated in remote areas which are difficult to reach," said Mr Shrestha.
Glacial Lake Outburst Floods (GLOFs) are not a new phenomenon but there is evidence that the frequency of such events has risen over the past three decades. For example the Bhutan's Raphstreng Tsho glacial lake in the Pho Chhu River sub-basin measured 1.6 km long, 0.96 km wide and was 80 metres deep in 1986. The latest figures (1995) show the lake has swollen to be 1.94 km long, 1.13 km wide and has a depth of 107 metres. Its neighboring glacier could generate a GLOF up to two-and-a-half-times that which caused major devastation in October 1994. The 43 other glacial lakes, pin pointed in the survey and deemed to be in a dangerous state, show similar patterns The filling of the lakes, and the threat of their mud and debris walls being breached, is as a result of rising temperatures melting the glaciers. Satellite, mapping and other surveys indicate that, for example, the glaciers in Bhutan are retreating at a rate of 30 to 40 metres a year
An early warning system for GLOF and rainstorm will also be developed and maintained in the pilot basins of Mangdechu and the Chamkharchu. "As of now, we don't have a dedicated centre for weather or flood forecast," an official from the hydro-met service department, said. "With the NWFFWC, we can expect a more systematic method of forecast that will provide reliable and accurate information." The current weather forecast used is the MetGIS model that was developed by the hydro-met service department in collaboration with the department of Met and geophysics of Vienna university in 2010. Prediction for Bhutan also depends on the weather forecast of the whole South Asian region. The early warning system that will be set up at the basins of Mangdechu and Chamkharchu will help downstream communities of Trongsa, Bumthang and Zhemgang, should a GLOF or rainstorm flood occur. Such warning systems are necessary as there were lakes in Trongsa and Bumthang listed among the 25 potential dangerous lakes in the country. "While we can't prevent disasters from occurring, we can at least minimise the damages or risks," a hydromet official said. "That's the sole objective." Disaster response will also be targeted within the project that is expected to cost approximately USD 3 to 4M. JICA had deputed a survey team to conduct the feasibility and detailed design of the project. The minutes of the meeting between JICA and hydro-met department was signed yesterday by the director of detailed planning survey team of JICA, Shiro Nakasone, and the director of the hydro-met service department, Karma Tshering. JICA is also expected to depute long- and short-term experts to implement the project. A bilateral agreement on the project will be signed between JICA and the gross national happiness commission.
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