Samples of ice from Mont Blanc are to be sent to Antarctica where they will be preserved for future research because glaciers in the French Alps are melting at an accelerating rate.
Future generations of scientists will be able to study climate change and the impact of pollution by using air bubbles trapped in the ice. The samples, which will be kept at the French-Italian Antarctic base of Concordia, will constitute “an invaluable scientific legacy,” said Jean Jouzel, a climatologist.
Researchers will be dropped by helicopter at an altitude of 4,300 metres on the Col du Dôme glacier next month and will spend two weeks drilling into the ice to collect samples 130 to 140 metres long.
They will provide a record of how the composition of the air and ice changed over a period of 150 years, revealing pollution from sulphur and nitrogen dioxide.
The effect of specific events such as the Chernobyl nuclear disaster, which caused a surge in the radioactive isotope Cesium 137 in snow that fell in 1986, may also be studied from the samples.
Alpine glaciers, which are huge sheets of snow and ice, are all shrinking, said Jérôme Chappellaz, a glaciologist. Scientists believe glaciers in the French Alps below than 3,500 metres will have vanished by the end of the century.
“At the Col du Dôme, we measured a temperature increase of 1.5 ºC in the space of 10 years,” Dr Chappellaz said. “The problem starts when the glacier reaches a positive surface temperature and starts melting, which disturbs the lower layers.”
Water seeps into the glacier, altering the chemistry of the ice. “The memory of the glacier is then damaged and risks being lost,” Dr Chappellaz said.
Source: Telegraph