European glaciologists drilling an ice core from the highest point of the Greenland ice sheet expect to reach bedrock, 3050 metres below, this week.
The Greenland Icecore Project is on target for two world records. The bottom layers of the core contain the oldest ice ever recovered, and the drill has gone deeper than anywhere else. 'We believe the ice at the bottom is between 200 000 and 500 000 years old,' says field leader Henrik Clausen. 'This will make it possible to gain a better understanding of how and why ice ages start and end.'
The GRIP ice core is a unique archive of past climate and atmospheric chemistry which will improve climate models.
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