A recent discovery is shaking up our understanding of Greenland's glacial history.
Although nearly the entire island is covered with ice today, new evidence suggests that this icy cover did not exist less than a million years ago. This revelation raises questions about the future stability of the ice sheet and its implications for rising sea levels.
In 1993, an ice core drill collected from the center of Greenland revealed the presence of fossils in the underlying sediments, but these discoveries were initially overlooked.
It wasn't until a new analysis, led by geologist Paul Bierman, that the significance of these fossils was recognized. The remnants found, such as Arctic poppy seeds and willow fragments, indicate a time when Greenland was covered by flourishing tundra.
This discovery is supported by previous studies that had already highlighted the existence of an ice-free Greenland several hundred thousand years ago. The recently reanalyzed fossils suggest that the center of the island, now buried under more than 2 miles (over 3 kilometers) of ice, would have been free from this ice layer during a time of warmer climate.
The past disappearance of ice in Greenland, at a time when atmospheric carbon dioxide levels were lower than today, suggests the possibility of this phenomenon repeating in the future. A complete melt of the Greenland ice sheet would cause a significant rise in sea levels, impacting coastal areas globally.
Image: Halley Mastro/University of Vermont
However, there is a glimmer of hope. Greenland has experienced ice melt followed by reformation before. This suggests that natural mechanisms could allow for the regeneration of the ice sheet, even after periods of extreme climate warming. The future of this region, crucial for global climate balance, remains uncertain.