Tag Archives: meltwater

Subglacial Lake Drainage Operation Commences

By Richard Gravelle

Engineers have begun an operation to drain a meltwater lake that has formed beneath a glacier in the Mont Blanc massif.

The lake, which lies underneath the Tete-Rousse glacier, threatens to flood the Saint Gervais valley with approximately 65,000 m3 of meltwater.  The valley is home to around 3,000 people, and contains the world-famous ski resort of Chamonix, so the effects of the lake draining could be catastrophic.  A previous flood in 1892 from another subglacial lake killed 175 people.

It is believed that warmer summer temperatures may have caused an increase in meltwater production which caused the lake to form, but that a period of cold temperatures may have closed a number of natural drainage routes, and preventing the water from draining away.

The engineers will have to drill a 40-50 m deep borehole in the glacier ice before they reach the lake water level.   The water can then be pumped away, making the valley safe once more.

It is thought that the drainage operation will cost around €2 (approximately £1,600,000).  However, if the project is successful, then the cost saved in human life and livelihoods will be far greater.

BBC News – France to drain lake under Mont Blanc Glacier, 25th August 2010

Spiegel – Subglacial Lake Threatens Alpine Community, 25th August 2010

Is climate change making Everest more dangerous?

By Richard Gravelle

In the same week as a British climber tragically died on Mount Everest, Nepalese Sherpas have reported that the effects of climatic warming have made the world’s highest mountain even more dangerous to climb.

A recent report from the Humanitarian Futures Programme has suggested that temperatures on the Tibetan plateau have increased faster than other areas in South Asia, resulting in increased rates of ice and snow melt, as well as less snowfall.  This has caused greater amounts of bare rock to be exposed on Mount Everest, increasing the risk of falling boulders, and making it difficult for climber’s ice axes and crampons to grip the climbing surface.  The report also highlights the threat of highly destructive glacial outburst floods which pose a risk not only to those on the mountain, but also those living in downstream areas.

Almost 3,000 climbers have reached the summit of Mount Everest since Sir Edmund Hillary and Tenzing Norgay’s first ascent in 1953.  At the end of a season which has seen around 250 climbers successfully complete the ascent, will climate change prevent this number from rising, and make the highest point on Earth inaccessible?

Sherpas warn ice melt is making Everest ‘dangerous – BBC News

Liverpool man dies after reaching Everest summit – BBC News

The Humanitarian Futures Programme Report: The Waters of the Third Pole