An illustration reveals how a landscape the scale of Belgium situated in Wilkes Land, East Antarctica, would seem if the thick ice sheet masking it have been lifted away.
| Photo Credit: Stewart Jamieson, Durham University/Reuters
Antarctica has not all the time been a desolate land of ice and snow. Earth’s southernmost continent as soon as was dwelling to rivers and forests teeming with life.
Using satellite tv for pc observations and ice-penetrating radar, scientists at the moment are getting a glimpse of Antarctica’s misplaced world. Researchers mentioned on Tuesday they’ve detected buried under the continent’s ice sheet an enormous historical landscape, replete with valleys and ridges, apparently formed by rivers earlier than being engulfed by glaciation way back.
This landscape, situated in East Antarctica’s Wilkes Land area bordering the Indian Ocean, covers an space roughly the scale of Belgium or the U.S. state of Maryland. The researchers mentioned the landscape seems to this point to not less than 14 million years in the past and maybe past 34 million years in the past, when Antarctica entered its deep freeze.
“The landscape is like a snapshot of the past,” mentioned Stewart Jamieson, a professor of glaciology at Durham University in England and co-leader of the examine revealed within the journal Nature Communications.
“It is difficult to know what this lost world might have looked like before the ice came along, but it was certainly warmer back then. Depending how far back in time you go, you might have had climates that ranged anywhere from the climate of present-day Patagonia through to something more approaching tropical. Ancient palm tree pollen has been discovered from Antarctica, not far around the coast from our study site,” Jamieson added.
Such an atmosphere doubtless would have been populated by wildlife, Jamieson added, although the area’s fossil file is simply too incomplete to point which animals could have inhabited it.
The ice above the traditional landscape measures about 2.2-3 km thick, in response to examine co-leader Neil Ross, a professor of polar science and environmental geophysics at Newcastle University in England.
The researchers mentioned the land beneath this ice is much less well-known even than the floor of Mars. They mentioned one method to unlock its mysteries can be to drill via the ice and procure a core pattern of sediments under. This may safe proof revealing the traditional natural world, as was achieved with samples obtained in Greenland relationship again 2 million years.
The new examine used satellite tv for pc observations of the ice floor, which in some locations adopted the contours of the buried landscape, and ice-penetrating radar information from a aircraft flying over the location.
Some earlier research equally have revealed historical landscapes beneath Antarctica’s ice together with mountains and highlands, although the landscape found within the new examine was the primary of its kind.
“The landscape has been modified by different processes influenced by rivers, tectonics and glaciation over a very long period of geological time,” Ross mentioned.
Right earlier than 34 million years in the past, Antarctica’s landscape and flora doubtless resembled as we speak’s chilly temperate rainforests of Tasmania, New Zealand and South America’s Patagonia area, Ross added.
Antarctica was as soon as a part of the Gondwana supercontinent that additionally encompassed what’s now Africa, South America, Australia, the Indian subcontinent and the Arabian Peninsula, however ultimately cut up off and have become remoted in a geological course of known as plate tectonics.
Jamieson mentioned the researchers suppose that when Antarctica’s local weather was hotter, rivers flowed throughout the newly recognized landscape towards a continental shoreline that was created as the opposite land plenty broke away. When the local weather cooled, Jamieson mentioned, some small glaciers fashioned on hills subsequent to the rivers, with valleys deepening amid glacial erosion.
“Then the climate cooled more significantly, and an ice sheet grew which covered the whole continent, swamping any glaciers that had existed before. When that ice growth occurred, the conditions between the base of the ice and the landscape changed to become very cold – and in this way it was no longer able to erode our landscape. Instead, the landscape got preserved, likely for 34 million years,” Jamieson added.
