Antarctica melting away at alarming rate


"As climate warming and ozone depletion send more ocean heat toward those sectors, they will continue to contribute to sea level rise from Antarctica in decades to come", said Rignot, who's also a senior project scientist at JPL.

The regions of ice which are close to warm water tend to be the ones where ice mass loss is the worst, Rignot added. More concerning is that the pace of ice sheet melting is going to cause catastrophic sea level rise in the following years.

"As the Antarctic ice sheet continues to melt away, we expect multi-metre sea level rise from Antarctica in the coming centuries", PTI quoted Eric Rignot, professor at the University of California, Irvine in the United States, as saying.

In December, a study presented by geologists suggested that if the West Antarctic ice sheet (WAIS) melted, it could cause a massive global flood.

According to a new study published Monday, Jan. 14, 2019, in Proceedings of the National Academy of Sciences, Antarctica is melting more than six times faster than it did in the 1980s.

The PNAS study estimated that Antarctica lost 169 billion tonnes of ice from 1992-2017, above the 109 billion tonnes in the same period estimated a year ago by a large global team of researchers.

Furthermore, the study shows how the East Antarctica region has played a significant role in the trends that were identified.

However, Antarctica's ice sheet - composed of the East Antarctic Ice Sheet and the West Antarctic Ice Sheet - is not a giant mass of stationary ice but rather a system with inputs and outputs of matter and energy.

Climate scientist Michael Oppenheimer of Princeton University, told Science magazine it "changes the ball game for sea level rise in this century". The melting seen in West Antarctica and the Antarctica Peninsula account for about four-fifths of the ice loss. From 1979 to 2001, it was an average of 48 gigatonnes annually per decade.

"The places undergoing changes in Antarctica are not limited to just a couple places", Rignot said. That figure rose to 252 billion tonnes lost per year from 2009 through 2017. "It surprises most people to learn that 20,000 years ago, sea level was 400 feet lower than today", explains John Englander, an expert on sea level rise and author of the book "High Tide On Main Street".

The melting in the area "increases the risk of multiple meters (more than 10 feet) sea level rise over the next century or so", Rignot said.

Another troublesome finding in the study was the fact that East Antarctica has also been losing ice significantly over the same time period.

The A-68 iceberg separated from the Larsen C ice shelf in July 2017. But across the Transantarctic mountains to the east, there's a much larger mantle of ice that's generally thought to be keeping its chill.

But a shift in wind patterns around Antarctica, induced by climate change, has led some to believe warm water carried by a circular current off the continental shelf has started invading the ice.

"Sea ice creates a barrier between the ocean and the ice", Levy said.