Largest ice sheet on Earth was stable throughout last warm period

Media playback is unsupported on your device                  Media caption Pippa Whitehouse

Media playback is unsupported on your device Media caption Pippa Whitehouse"Push a balloon filled with honey- it rebounds when you remove your hand

And the ice losses quickened to 219 billion tons a year since 2012, from 76 billion previously. "This has to be a concern for the governments we trust to protect our coastal cities and communities". That's up from 84 billion tons ten years ago, and 54 billion tons ten years before that.

An global team of polar scientists found that melting in Antarctica has jumped sharply from an average of 76 billion tonnes per year prior to 2012, to around 219 billion tonnes each year between 2012 and 2017.

More than 90 percent of that frozen water sits atop East Antarctica, which has remained mostly stable even as climate change has driven up Earth's average surface temperature by a full degree Celsius (1.8 degrees Fahrenheit).

While some of that loss is due to natural processes-the calving of coastal glacials is part of the natural life cycle of Antarctica's ice sheets-the research describes what's happening as "an important indicator of climate change".

Altogether, across the continent, 34,000 square kilometers (13,000 square miles) of the ice shelf has been lost since the 1950s.

The frozen continent lost nearly 3 trillion tons of ice between 1992 and 2017, the 84 scientists said in what they called the most complete overview of Antarctic ice to date. Marine-based ice very well could and in fact is already starting to contribute, and that alone holds an estimated 20 meters of sea level rise.

The research team measured isotopes produced by the interaction between cosmic rays and the nucleus of an atom, called cosmogenic nuclides, in glacial sediment from Antarctic's largest ice shelf. All that water made global oceans rise about three-tenths of an inch (7.6 millimeters).

"The work is consistent with previous studies indicating massive losses of ice in West Antarctica and on the Antarctic Peninsula, but it brings the estimates up to date and confirms that they are significant", Bethan Davies, a lecturer at the University of London who wasn't involved with the study, told Earther.

Worryingly, the paper demonstrates that the rate of ice loss has tripled in recent times.

"To see a threefold increase just since 2012 - that's disturbing to me", said Brenda Ekwurzel, director of climate science for the Climate and Energy Program at the Union of Concerned Scientists.

While some people blame climate change for the rapid melting ice caps, others blame underground heat sources such as volcanoes.

As shown in the video above, these changes are not uniform over the entire Antarctic ice sheet.

"According to our analysis, there has been a steep increase in ice losses from Antarctica during the past decade, and the continent is causing sea levels to rise faster today than at any time in the past 25 years", he added.

"The fate of Antarctica, the fate of Greenland, is the fate of Miami", she said. Sea level rise is a threat to cities from NY to Shanghai as well as low-lying nations from the Pacific Ocean to the Netherlands.

For the new study, the scientists combined data from three types of satellite measurements to track changes in ice over time, study co-author Andrew Shepherd, a professor of Earth observation with the School of Earth and Environment at the University of Leeds in the United Kingdom, told Live Science.

"Whilst there's still considerable uncertainty about East Antarctica mass balance, it is increasingly clear that ice loss from West Antarctica has accelerated", said Kate Hendry, a researcher at the University of Bristol, commenting on the findings.

"We depend upon the satellite measurements to not only tell us how the ice sheets respond but also to make these calculations to sea-level contribution", Shepherd said.

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