Antarctica in unprecedented detail: Most complete map ever made reveals the continent is shrinking rapidly


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A stunning new map that reveals a shrinking Antarctica in unprecedented detail has been made available to the public.

The map, which was created by stitching together 3,150 individual satellite images, offers the most detailed view of the continent since 1997.

By comparing it to earlier maps of the same regions, scientists have found large chunks of ice in the Antarctic disappearing into the surrounding waters.

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The map, which was created by stitching together 3,150 individual satellite images, offers the most detailed view of the continent since 1997. The Canadian Space Agency, along with the University of Waterloo, collected the images over several months in 2008 aboard the RADARSAT-2 satellite

The map, which was created by stitching together 3,150 individual satellite images, offers the most detailed view of the continent since 1997. The Canadian Space Agency, along with the University of Waterloo, collected the images over several months in 2008 aboard the Radarsat-2 satellite

The Canadian Space Agency, along with the University of Waterloo, collected the images over several months in 2008 aboard the Radarsat-2 satellite.

This satellite was able to cut through cloud cover to get a more accurate reading. Its high-resolution images were then tiled together into a coast-to-coast view of the entire continent.

'These colours in a nutshell represent different physical characteristics of the ice, which the scientist can interpret,' Professor Ellsworth LeDrew, director of the Canadian Cryospheric Information Network, told Emily Gertz at Popular Science.

'It's what is called polarimetric information. It's like looking through a camera's polarising filter. Some wavelengths are up and down and some are side to side.'

This satellite was able to cut through cloud cover to get a more accurate reading. Its high-resolution images were then tiled together into a coast-to-coast view of the entire continent. This image shows a closeup view of Antarctica near the Ronne Ice Shelf

This satellite was able to cut through cloud cover to get a more accurate reading. Its high-resolution images were then tiled together into a coast-to-coast view of the entire continent. This image shows a closeup view of Antarctica near the Ronne Ice Shelf

ANTARCTIC BEGAN MELTING 5,000 YEARS EARLIER THAN THOUGHT

The Antarctic ice sheet is more unstable than first thought with a recent study suggesting melting began 5,000 years earlier than previously believed.

The study was conducted by an international team including researchers from Germany, Canada, Hawaii, Lapland and Australia. 

It reveals that shrinking of the vast ice sheet accelerated during eight distinct periods between 20,000 and 9,000 years ago.

During one period 14,600 years ago, melting glaciers released so many icebergs into the ocean that sea level rose 6.5ft (two metres) in just 100 years.

The results provide the first clear evidence for dramatic melting in Antarctic's and reflect predictions for the region's future. It also follows recent news that destabilisation of part of the West Antarctic ice sheet has already begun and could be 'unstoppable.'

Professor LeDrew added that scientists can use the data to show see where the edge of a glacier is, or where the ice is thinning as land bound glaciers expand towards the sea. Ships also use the information for navigation, he says.

The map is currently available free of charge to the public online, via the Polar Data Catalogue.

'The Earth's polar regions are considered a bellwether for the effects of climate change,' said Professor LeDrew.

'When compared to the previous Antarctic mosaic, we can map changes in the icescape with unprecedented accuracy and confidence.'

A similar mosaic for Greenland is currently underway and the researchers plan to continue creating mosaics of Antarctica every few years in order to track ice cover.

Earlier this year, Nasa said vast glaciers in West Antarctica seem to be locked in an irreversible thaw linked to global warming that may push up sea levels for centuries.

In a few hundred years they say the irreversible melt that has already started could eventually add four to 12ft (1.2 to 3.7m) to current sea levels.

A Nasa study looking at 40 years of ground, airplane and satellite data of what researchers call 'the weak underbelly of West Antarctica' shows the melt is happening faster than scientists had predicted, crossing a critical threshold that has begun a domino-like process.

Evidence shows 'a large sector of the West Antarctic ice sheet has gone into a state of irreversible retreat', says lead author Eric Rignot of the University of California, Irvine, and Nasa's Jet Propulsion Laboratory in Pasadena, California.

The coastal ends of the glaciers rest on bedrock below sea level, holding back a vast weight of ice and making them vulnerable to melt, he said.

'It does seem to be happening quickly,' says University of Washington glaciologist Ian Joughin, lead author of a separate study into the same phenomenon. 'We really are witnessing the beginning stages.' 

Zoom in on this image to see the world's most complete map of Antarctica



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