What’s wrong with Antarctica? NASA says it’s gaining more ice than losing

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What’s wrong with Antarctica? NASA says it’s gaining more ice than losingA new NASA study says that an increase in Antarctica snow accumulation that began 10,000 years ago is currently adding enough ice to the continent to outweigh the increased losses from its thinning glaciers.
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This study contradicts a 2013 report by the Intergovernmental Panel on Climate Change (IPCC) which says that Antarctica is overall losing land ice.

The Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008, according to the new analysis of satellite data.

“We’re essentially in agreement with other studies that show an increase in ice discharge in the Antarctic Peninsula and the Thwaites and Pine Island region of West Antarctica,” said Jay Zwally, a glaciologist with NASA Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study, which was published on Oct 30 in the Journal of Glaciology.

“Our main disagreement is for East Antarctica and the interior of West Antarctica – there, we see an ice gain that exceeds the losses in the other areas.”

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Zwally added that his team “measured small height changes over large areas, as well as the large changes observed over smaller areas.”

While other scientists have assumed that the gains in elevation seen in East Antarctica are due to recent increases in snow accumulation, Zwally's team used meteorological data beginning in 1979 to show that the snowfall in East Antarctica actually decreased by 11 billion tons per year during both the ERS and ICESat periods. They also used information on snow accumulation for tens of thousands of years, derived by other scientists from ice cores, to conclude that East Antarctica has been thickening for a very long time.

But it might only take a few decades for Antarctica’s growth to reverse.

If the losses of the Antarctic Peninsula and parts of West Antarctica continue to increase at the same rate they’ve been increasing for the last two decades, the losses will catch up with the long-term gain in East Antarctica in 20 or 30 years.

"I don’t think there will be enough snowfall increase to offset these losses," Zwally said.

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“The good news is that Antarctica is not currently contributing to sea level rise, but is taking 0.23 millimeters per year away,” Zwally added.

But there is also a bad news - if the 0.27 millimeters per year of sea level rise attributed to Antarctica in the IPCC report is not really coming from Antarctica, there must be some other contribution to sea level rise that is not accounted for.

(Image credits: NASA)