Meltdown threatens villages in European Alps By PAUL BROWN LONDON Friday 5 January 2001

Permafrost holding together the highest peaks in the Alps and other European mountain ranges is melting and threatening alpine villages and ski resorts with devastating rock falls and landslides.

Some villages may have to be evacuated and there are fears that rivers may be blocked by debris, causing potential flash floods when the unstable dams created subsequently collapse.

The European Union has launched a permafrost monitoring program to predict when disasters may occur and isolate unstable areas. Scientists blame the changes on global warming.

Dr Charles Harris, from the earth sciences department at Cardiff University in Wales who coordinates the research for the EU, said the main risks were in the Alps in Switzerland, Austria, France, Germany and Italy, with their dense populations and steep slopes. Among the places being monitored are the Murtel-Corvatsch mountain, above fashionable St Moritz, and the Schilthorn, which towers above the Muran and Gandeg resorts, near Zermatt.

He told a Royal Geographical Society/Institute of British Geographers' conference in Plymouth this week: "A bore hole sunk above St Moritz 15 years ago shows the temperature of the ground has risen half a degree to one degree in that time. If the temperature inside the mountain is only -2C at the moment, then it will not take long to defrost."

There already were rock falls, landslides, mud flows, debris and slush flows in Switzerland as the ice melted and weakened the mountains. These were certain to increase. "What we do not understand is how big these falls might get. Whole mountainsides could go at once, potentially crushing settlements, cutting railway lines and roads. We need to try to understand and predict this process," he said.

Dr Harris said Swiss officials "are very worried about the future of their mountain communities and where they can continue to live with this increasing level of risk".

A new organisation called Pace (Permafrost and Climate in Europe) has been set up to monitor the effects of climate change on the mountains' stability.

The surface soil and rock temperature rises above zero in the summer and freezes again in winter, while a few centimetres inside the mountains the ice is permanent, or has been for thousands of years. Pace literature says: "The combination of ground temperatures only slightly below zero, high ice contents and steep slopes, makes mountain permafrost particularly vulnerable to even small climate changes."

To their surprise, researchers have shown that in high mountains permafrost exists as far south as the Sierra Nevada in Spain. Although ice was only in the tops of the mountains in Spain, it started at about 2500 metres in the Alps and 1500metres in Sweden. In Svalbard in the high Arctic it was at sea level.

A series of bore holes across Europe was monitoring how deep the permafrost went and how cold the rocks in mountains were. The colder the temperature, the stronger the ice, so, as it warmed, the mountains might collapse before the permafrost completely melted. Most falls were expected in the summer and autumn but that might not always be the case, Dr Harris said.

Other mountain ranges with permafrost being monitored are the Pyrenees on the French-Spanish border, the Jotunheim range in Norway and Abisko range in Sweden. Other bore holes are in Svalbard, the islands north of Norway, where coal is mined in the permafrost and the buildings have their foundations on frozen soil as hard as rock.

There are fears that the buildings will fall over if the frost melts.This could be a serious problem in the higher ski resorts where foundations of ski lifts and other buildings were built on the assumption the ground would remain stable.

Dr Harris said the bore holes recently sunk were too new to assess long-term trends. That would come over the next 10, 20 and even 50 years.

"From our calculations we already know that the tops of the mountains have warmed one or two degrees in the past 100 to 150 years. That is at a far quicker rate than the speed of global warming generally," he said.

GUARDIAN

This story was found at: http://www.theage.com.au/news/2001/01/05/FFXBWCWAJHC.html

-- Martin Thompson (mthom1927@aol.com), January 04, 2001