Greenland Ice Sheet Froze Landscape in Time for 3 Million Years

Deep beneath the Greenland ice sheet, preserved for over 3 million years, is an ancient landscape. Now, scientists are taking a closer look at this landscape, revealing a bit more about the history of the area.

The researchers actually took an ice core sample more than 3,000 meters long and then analyzed the chemical composition of silts from the bottom of the core. This allowed them to find that pre-glacial landscapes can actually be preserved for long periods beneath continental ice sheets. Not only that, but the findings suggest that ice has continually covered the area for the past few million years with, at most, brief exposure. This tells the scientists a bit more about the history of the climate in the area.

So what was the landscape like? Fossils found in northern Greenland reveal that there was a green and forested landscape prior to the time that the ice sheet began to form. Once the ice did form, though, it stayed; even during the warmest periods, the Greenland ice sheet remained stable and locked away the soils beneath it.

"Rather than scraping and sculpting the landscape, the ice sheet has been frozen to the ground, like a giant freezer that's preserved an antique landscape," said Paul R. Bierman, one of the researchers, in a news release.

The findings don't just reveal how the ice sheet behaved in the past, though. It may also reveal how the ice will behave in the future. As global temperatures continue to rise, it's important to understand how ice sheets will react to the warmer weather. By looking at the past, scientists can better predict what might happen as our climate changes.

Now that researchers know that the Greenland ice sheet has remained stable for so long, they can better understand how the release of freshwater from the ice sheet might impact rising sea levels and the surrounding landscape.