Gravity data reveals Antarctic ice sheet is melting at ever faster rate

A team of researchers has found that Antarctica's massive ice sheet lost twice the amount of ice in its western portion compared with what it accumulated in the east, suggesting that the southern continent's ice cap is melting ever faster.

The Princeton University researchers, who weighed Antarctica's ice sheet using gravitational satellite data, found that from 2003 to 2014, the ice sheet lost 92 billion tons of ice per year, adding that if stacked on the island of Manhattan, that amount of ice would be more than a mile high, more than five times the height of the Empire State Building.

The researchers found that since 2008, ice loss from West Antarctica's unstable glaciers doubled from an average annual loss of 121 billion tons of ice to twice that by 2014 and the ice sheet on East Antarctica, the continent's much larger and overall more stable region, thickened during that same time, but only accumulated half the amount of ice lost from the west.

Co-author Frederik Simons said that they have a solution that is very solid, very detailed and unambiguous, adding that a decade of gravity analysis alone cannot force you to take a position on this ice loss being due to anthropogenic global warming.

Simon noted that all they have done is take the balance of the ice on Antarctica and found that it is melting, but with the rapidly accelerating rates at which the ice is melting, and in the light of all the other, well-publicized lines of evidence, most scientists would be hard pressed to find mechanisms that do not include human-made climate change.

Compared to other types of data, the Princeton study shows that ice is melting from West Antarctica at a far greater rate than was previously known and that the western ice sheet is much more unstable compared to other regions of the continent, said first author Christopher Harig.

Harig added that the fact that West Antarctic ice-melt is still accelerating is a big deal because it's increasing its contribution to sea-level rise and it really has potential to be a runaway problem. It has come to the point that if they continue losing mass in those areas, the loss can generate a self-reinforcing feedback whereby they will be losing more and more ice, ultimately raising sea levels by tens of feet.

The study appears in the journal Earth and Planetary Science Letters.