Ice cores show quick loss of Antarctic ice 8,000 years ago

The British Antarctic Survey and researchers at the University of Cambridge have found the first concrete proof that the West Antarctic Ice Sheet abruptly and dramatically shrank eight thousand years ago, at the end of the Last Ice Age.

Evidence from an ice core reveals that in one place, the ice sheet thinned by 450 meters in less than 200 years, which is greater than the height of the Empire State Building.

This is the first sign of such a rapid ice loss that has been found anywhere in Antarctica. Scientists are concerned that the West Antarctic Ice Sheet may eventually become unstable due to the present warming trends, possibly reaching a tipping point and causing a rapid collapse.

Add WION as a Preferred Source

The new studypublished on February 8, in Nature Geoscienceprovides insight into how quickly Antarctic ice could melt if temperatures continue to rise.

Also Read:Antarctica likely warming much faster than climate change models predicted: Study

The senior author of the new study from Cambridge Department of Earth Sciences, Professor Eric Wolff, stated, "We now have direct evidence that this ice sheet suffered rapid ice loss in the past. If portions of this ice sheet become unstable, this scenario could occur again and is not limited to the predictions of our model."

Enough freshwater is there in the Antarctic ice sheets from west to east to increase sea levels worldwide by about 57 meters. Because so much of the West Antarctic Ice Sheet rests on bedrock that is below sea level, it is thought to be especially vulnerable.

Sea levels could rise if a significant portion of the West Antarctic Ice Sheet disappears in the coming centuries, according to model projections.

Dr. Isobel Rowell, a British Antarctic Survey study co-author, explained, "We wanted to know what happened to the West Antarctic Ice Sheet at the end of the Last Ice Age, when temperatures on Earth were rising, albeit at a slower rate than current anthropogenic warming. We can go back in time and estimate the thickness and extent of the ice sheet using ice cores."

"The exact date of the ice thinned was unknown, but we already knew from models that it happened around this time," Rowell said. Models of the ice sheet indicated that the retreat occurred between 12,000 and 5,000 years ago, but they were unable to pinpoint its exact timing. "It is possible to incorporate this precisely dated observation of that retreat into better models," stated Rowell.

(With inputs from agencies)