Antarctica is Losing Twice as Much Ice as it was During Previous Survey: Sea Levels Rise

It turns out that Antarctica is now losing its ice at a rate that's twice as fast as when it was last surveyed. Scientists have found that the Antarctic ice sheet is now losing 159 billion tons of ice each year.

The polar ice sheets are major contributors to global sea level rise. In fact, the new findings reveal that Antarctic losses are enough to raise global sea levels by .45 millimeters each year alone.

In order to measure the ice sheet, the researchers used measurements collected by the European Space Agency's CryoSat-2 satellite mission. This satellite carries an altimeter that specially designed to measure the Antarctic ice. The CryoSat-2 did just survey the ice sheet, though; it surveyed virtually all the Antarctic continent, reaching to within 215 kilometers of the South Pole and leading to a fivefold increase in the sampling of coasting regions where ice losses are concentrated.

So what did the researchers find? It turns out that overall, the melting is concentrated near glaciers thinning in the Amundsen Sea sector of West Antarctica. On average, West Antarctica lost 134 gigatons of ice, East Antarctica lost three gigatons and the Antarctica Peninsula lost 23 gigatons of ice in each year between 2010 and 2013. That's a total loss of 159 gigatons each year.

"Thanks to its novel instrument design and to its near-polar orbit, CryoSat allows us to survey coastal and high-latitude regions of Antarctica that were beyond the capability of past altimeter missions, and it seems that these regions are crucial for determining the overall imbalance," said Andrew Shepherd, one of the researchers, in a news release. "Although we are fortunate to now have, in CryoSat-2, a routine capability to monitor the polar ice sheets, the increased thinning we have detected in West Antarctica is a worrying development. It adds concrete evidence that dramatic changes are underway in this part of our planet, which has enough ice to raise global sea levels by more than a meter."

The findings reveal that it's more important than ever to examine this region as ice continues to melt. As sea levels rise, it's crucial to monitor how fast that rate might increase in the future in order to better prepare coastal areas.

The findings are published in the journal Geophysical Research Letters.