Scientists probe ancient ice
2003-11-18 07:54
Germany - Scientists in Germany are handling the oldest ice that has ever been unearthed in what is hoped will provide important information on climate change.
Around 120 chunks of ice, each around half a metre long and 10 centimetres in diameter, are being examined by the Alfred Wegener Institute for Polar and Marine Research (AWI) in Bremerhaven.
The ice cores, which were drilled during last winter in the Antarctic, are up to 900 000 years old.
The ice comes from a depth of 3 200 metres and contains information about the climate and atmosphere of former times.
The drilling was part of the European Project for Ice Coring in Antarctica (Epica), a joint effort by 12 institutions from 10 European countries.
As part of the project two deep ice cores are currently being drilled for climate research - at the French station Dome C and one at the German Kohnen station, which is run by the AWI.
Scientists have begun slicing the ice into layers, making digital recordings of the sections and examining the ice crystals.
Glaciologist Hubertus Fischer from AWI said it is hoped to discover how the atmosphere is altered by warm and cold periods on earth.
"In the past 800 000 years earth has experienced a change in warm and cold periods every 100 000 years, and before that every 40 000 years," he said.
Periods of cold or warm came about as a result of long-term changes to the sun's rays.
Previous research on ice cores has shown that the atmosphere contains considerably more carbon dioxide during warm periods.
However, although greenhouse gases such as carbon dioxide and methane strengthen the warming process they are not the sole cause, he said. - Sapa-dpa
- SAPA