Greenland’s ice sheet probably first formed something like three million years ago, and drilling ice cores there has produced reliable data on changes in the Climate since then :-
“Bedrock has been reached Tuesday July 27 2010 at the deep ice core drilling site NEEM on the Greenland Ice Sheet at the depth 2537.36 m. The Eemian is the last interglacial period, when climate was warmer than today, and sea level 5 meters higher, and is our best analogue for future climate. Scientists from 14 nations participated in NEEM, the most international ice core effort to date. After five years of work, ice from the warm interglacial Eemian period, 130.000 to 115.000 years before present and even older ice has been recovered. The last 2 m of ice above the bedrock contains rocks and other material that has not seen sunlight for hundreds of thousands of years. We expect the ice to be rich in DNA and pollen that can tell us about the plants that existed in Greenland before the site became covered with ice, perhaps as long as 3 million years ago…”
Further ice core work will obviously have to take place deep in Greenland’s interior, because of the encroaching coastal areas of the ice sheet that are experiencing increasing meltdown :-
Melting of the whole volume of the Greenland ice sheet appears to be accelerating – read this report from SkepticalScience.com for more :-
So, an ice sheet that’s been relatively stable for over one hundred thousand years is now melting at an accelerating rate ?
And perhaps it could all melt before we’ve properly studied it ?
Shouldn’t we be just a teensy weensy little bit concerned ?