Science & Tech · Science & Environment · 16 hrs ago
Greenland ice sheet retreated more than 60 miles 416,000 years ago
A University at Buffalo-led study found that Greenland’s ice sheet retreated more than 60 miles around 416,000 years ago.
The evidence came from sediment drilled from nearly a mile beneath Camp Century, a former U.S. Army base under Greenland’s ice.
By studying molecules made by bacteria in the sediment, researchers estimated that summers there were 4.7°C warmer than today.
The site stayed ice-covered during a later period with similarly warm summers, about 5,000 to 10,000 years ago.
The researchers suggest that the earlier warm period lasted much longer, giving the ice more time to melt.
The findings matter because how long warming lasts can shape ice loss, as well as how Greenland’s ice sheet responds to future warming.
A study estimates that Greenland’s ice sheet retreated more than 60 miles from its present edge near Camp Century about 416,000 years ago.
Researchers estimate that summers there were 4.7 degrees Celsius warmer than today during the ice-free period.
The study analyzed sediment recovered from nearly a mile beneath the ice during drilling in the 1960s.
The researchers say the length of the ancient warm period may help explain the retreat.
The findings were published in the journal Climate of the Past.
- Who
- A University at Buffalo-led research team, including lead author John Michael Aguilar.
- What
- The study estimates that Greenland’s ice sheet retreated more than 60 miles near Camp Century and that summers there were 4.7 degrees Celsius warmer than today.
- When
- About 416,000 years ago.
- Where
- Camp Century, Greenland.
- Why
- Warmer summers accompanied the retreat; researchers suggest the warm period may have lasted long enough for the ice sheet to melt substantially.
This story does not have two clearly opposing sides.
The ground beneath Camp Century was exposed, and the ice sheet’s edge in the region retreated more than 60 miles from its present position.
Greenland experienced similarly warm summers, but Camp Century remained covered by ice.
Researchers recovered sediment from nearly a mile beneath the ice during drilling at Camp Century.
SciTechDaily reported on the University at Buffalo-led study, published in Climate of the Past.
- Estimated retreat
- More than 60 miles (97 kilometers)
- Ancient period
- About 416,000 years ago
- Estimated summer temperature difference
- 4.7 degrees Celsius (8.5 degrees Fahrenheit) warmer than today
- Sediment depth
- Nearly a mile (1.6 kilometers) below the surface
- Journal
- Climate of the Past
What people are saying
It’s striking that a period of moderately warmer temperatures coincided with such a substantial retreat of the ice sheet.
This work gives us a better understanding of how the ice sheet responds to sustained warming and what may be possible in the future.