Greenland ice dome fully melted in past at temperatures possible this century

An ice dome in northern Greenland fully melted in the past at temperatures that could recur this century, offering new insight into how rapidly ice-sheet loss may drive global sea-level rise.

According to a study published Monday in the journal Nature, researchers found that Greenland's Luxembourg-sized Prudhoe Dome completely melted around 7,000 years ago, after drilling a deep ice core that revealed sun-bleached sand dating back to a warmer post-glacial period.

Scientists said the region experienced summers 3-5C warmer than today, temperatures that could return by 2100 as a result of human-caused climate change.

Greenland's ice sheet melt could drive sea levels up by several tens of centimeters to as much as 1 meter (3.2 feet) this century, prompting scientists to refine estimates by determining how quickly its different regions may vanish.

The Prudhoe Dome core adds to limited evidence from beneath Greenland's ice sheet showing the region was ice-free hundreds of thousands of years ago and that the entire ice sheet melted as recently as 1.1 million years ago.

While researchers cautioned that present-day melting differs from past events driven by natural orbital shifts, they said the findings can help improve climate models used to simulate how Greenland's ice sheet responds to warming.