Melting of Antarctic ice sheet under 2@C warming

  • Melting of Antarctic ice sheet under 2@C warming

Melting of Antarctic ice sheet under 2@C warming

The work was led by scientists at Australia's University of New South Wales Sydney, who set out to study the behavior of the West Antarctic Ice Sheet during a period known as the Last Interglacial, which took place around 129,000-116,000 years ago. This gap, formed at the ice level, coincides with the period when the sea levels are very high. Now, a terrifying piece of news surfaced when a new worldwide study led by UNSW Sydney shows that we're headed in that direction again.

We also measured temperature-sensitive water molecules across the blue ice area. Similarly, during the Heleson period, where we live in the hottest glacial period, an increase of 2 ° C in the ocean water may cause melting of the East Antarctic Ice Layer as well as the melting of the Western Antarctic Ice Layer.

"So the question is how much could fall into the ocean and this is where the last interglacial [period] is so important".

Washington D.C [US], Feb 12 (ANI): A study of the Antarctic ice sheet in a 2 degree Celsius warmer world demonstrates the importance of meeting the Paris climate agreement.

In contrast to the East Antarctic Ice Sheet - which mostly sits on high ground - the West Antarctic sheet rests on the seabed. As warmer ocean water travels into cavities beneath the ice shelves, ice melts from below, thinning the shelves and making the central sheet highly vulnerable to warming ocean temperatures.

Blue ice zones are created by catabatic winds, a type of wind observed in Antarctica. When these winds blow over mountains, they remove snow and ice, allowing ancient ice to come to the surface. As the ice is removed by the wind, ancient ice is brought to the surface, which offers insight into the ice sheet's history.

"Instead of drilling kilometers into the ice, we can simply walk across a blue ice area and travel back through millennia".

"This has been a big concern and is what the concern is in the present day", Turney said. During isotope measurements, the researchers discovered a gap just before the last interglacial.

Article: Chris S.M. Turney, Christopher J. Fogwill, Nicholas R. Golledge, Nicholas P. McKay, Erik van Sebille, Richard T. Jones, David Etheridge, Mauro Rubino, David P. Thornton, Siwan M. Davies, Christopher Bronk Ramsey, Zoë A. Thomas, Michael I. Bird, Niels C. Munksgaard, Paul G. Albert, Andres Rivera, Tas von Ommen, Mark Curran, Andrew Moy, Stefan Rahmstorf, Kenji Kawamura, Claud-Dieter Hillenbrand, Michael E. Weber, Christina J. Manning, Jennifer Young, Alan Cooper (2020): Early Last Interglacial ocean warming drove substantial ice mass loss from Antarctica. This conclusion was supported by examinations of fine volcanic ash and trace gases in the samples, along with the DNA of the bacteria trapped inside the ice. This indicates a period of sustained ice loss over thousands of years.

"The better we understand the climate of the past, the better we can deduce what this means for the future".

The sea level rise in the Last Interglacial can't be fully explained by the Greenland Ice Sheet melt, which accounted for a 2m increase, or ocean expansion from warmer temperatures and melting mountain glaciers, which are thought to have caused less than a 1m increase. Alarmingly, the results showed that most ice loss happened at the start of Last Interglacial warming, some 129,000 years ago - showing how sensitive the Antarctic is to higher temperatures.

Using data gained from their fieldwork, the team ran model simulations to investigate how warming might affect the floating ice shelves. These shelves now buttress the ice sheets and help slow the flow of ice off the continent.

In a new study, it was determined that the ice melting in Antarctica approximately 100,000 years ago increased the sea level by 3 meters.

"As it reaches the tipping point, only a small increase in temperature could trigger abrupt ice sheet melt and a multi-metre rise in global sea level".

"What these results suggest, or show, is that when people talk about a 2C warmer world as a good thing, actually what it shows is we don't want to get close to 2C", he said.

"We only tested one location, so we don't know whether it was the first sector of Antarctica that melted, or whether it melted relatively late", says Turney.