Ancient landscape discovered beneath East Antarctic Ice Sheet
The research team, led by Durham University, UK, used satellite data and radio-echo sounding techniques to map a 32,000 km2 area of land underneath the vast ice sheet.
They discovered a landscape that appears to have been formed by rivers at least 14 million years ago and possibly even before the initial growth of the East Antarctic ice around 34 million years ago.
This newly discovered landscape consists of ancient valleys and ridges, not dissimilar in size-and-scale to the glacially-modified landscape of North Wales, UK.
Its existence implies a long-term temperature stability of the ice sheet in the area investigated by the researchers.
The study has been published in the journal Nature Communications.
Lead author Professor Stewart Jamieson, in the Department of Geography, Durham University, UK, said: “The land underneath the East Antarctic Ice Sheet is less well known than the surface of Mars.
“And that’s a problem because that landscape controls the way that ice in Antarctica flows, and it controls the way it might respond to past, present and future climate change.
“So, we’re investigating a small part of that landscape in more detail to see what it can tell us about the evolution of the landscape and the evolution of the ice sheet.
“And what we find is an ancient land surface that has not been eroded by the ice sheet and instead it looks like it was created by rivers before the ice came along.
“This tells us that there hasn’t been a lot of change in this particular area, which indicates that although this part of the ice sheet may have retreated during warmer times in the past, the conditions at this site likely did not change much, and that helps us understand how the ice sheet might respond to future and ongoing warming.”
The study’s co-author Neil Ross, Professor of Polar Science and Environmental Geophysics at Newcastle University, UK, said: “It is remarkable that this landscape, ‘hidden in plain sight’ for many years, can tell us so much about the early, and long-term, history of the East Antarctic Ice Sheet, as well as helping us to understand how it might evolve in response to future climate change.
“This has been something of a slow burn project, but one that has now come to fruition in an exciting paper involving a great research team.”
The discovery builds on previous work by this team who, in collaboration with other researchers, have mapped out hidden mountain ranges, canyon systems and lakes beneath the ice in Antarctica.
Although the landscape beneath the ice sheet is not visible to the naked eye, satellite images captured over the region show small undulations of the ice sheet’s surface that provide clues about the sub-ice landscape.
In a few places, the landscape’s existence has been confirmed by using radio-echo sounding from planes to see through the ice and map the shape of the land beneath the ice sheet.
The research team proposes it is likely that there will be other, as yet undiscovered, ancient landscapes hidden beneath the East Antarctic Ice Sheet.
Professor Jamieson added: “We’ll continue exploring the landscape, doing our best to fill in gaps where surveys don’t exist, and using that information to understand how the ice sheet and its underlying landscape have changed over their long history.”
The survey data collection that underpins this work was supported by the UK Research and Innovation’s (UKRI) Natural Environment Research Council (NERC), the US National Science Foundation (NSF) and NASA.
ENDS
Media Information
Professor Stewart Jamieson of Durham University, UK, is available for interview and can be contacted on: stewart.jamieson@durham.ac.uk
Professor Neil Ross of Newcastle University, UK, is available for interview and can be contacted on: neil.ross@newcastle.ac.uk
Alternatively, please contact Durham University Communications Office for interview requests on: communications.team@durham.ac.uk.
Images and Captions
Associated images are available via the following link: https://bit.ly/405LbQg
Lifting the lid on Antarctica: Graphic shows how the landscape of Antarctica would appear if the ice were lifted away. Credit: Stewart Jamieson, Durham University
HighlandARadarSat: Satellite image of the ice surface from Radarsat with a ghost-like appearance of the mountain blocks beneath the ice. Credit: Stewart Jamieson, Durham University
HighlandARadarSatMappedLandscape: Satellite image of the ice surface from Radarsat with the valleys and ridges of the buried ancient mountains mapped. Credit: Stewart Jamieson, Durham University
RadarImage: A radar image displaying the peaks and valleys of the mountains which are buried under ice that is 2 km thick. Credit: Stewart Jamieson, Durham University
Plane1-5: Images of the plane used to conduct a partial survey of the region during the ICECAP project. Credit: ICECAP
Source Material
‘An ancient river landscape preserved beneath the East Antarctic Ice Sheet’ by Stewart S. R. Jamieson, Neil Ross, Guy J. G. Paxman, Fiona J. Clubb, Duncan A. Young, Shuai Yan, Jamin Greenbaum, Donald D. Blankenship, Martin J. Siegert is published in the journal Nature Communications. DOI: 10.1038/s41467-023-42152-2
A copy of the research paper is available by contacting communications.team@durham.ac.uk
The full paper can be accessed via the following link when the embargo lifts: https://www.nature.com/articles/s41467-023-42152-2
About Durham University
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We are a member of the Russell Group of leading research-intensive UK universities and we are consistently ranked as a top 10 university in national league tables (Times and Sunday Times Good University Guide, Guardian University Guide and The Complete University Guide).
For more information about Durham University visit: www.durham.ac.uk/about/
JOURNAL
Nature Communications
ARTICLE TITLE
‘An ancient river landscape preserved beneath the East Antarctic Ice Sheet’
ARTICLE PUBLICATION DATE
24-Oct-2023
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