The outlook for polar bears is ominous as our ice conditions grow more dire in Antarctica. The frigid continent saw a sixfold increase in annual ice loss between 1979 and 2017, according to analysis from University of California – Irvine, and all that melting ice has caused global sea levels to rise over half an inch during the same period.
“As the Antarctic ice sheet continues to melt away, we expect multi-meter sea level rise from Antarctica in the coming centuries,” lead study author Eric Rignot said in a press release.
Combining satellite photos with other data sources, Rignot and his team found that annual ice loss increased from 40 gigatons (1 gigaton is equal to 1 billon tons) in 1979 to 252 gigatons in 2017. Even more alarming, the ice loss has been accelerating more rapidly in recent years—up 280 percent from 2001 to 2017.
The specific causes of the ice melt are complex, but there are some clear culprits. Ice loss was highest in areas exposed to warm water under the ocean’s surface. Rising greenhouse gases and a warming climate has caused these pockets of warm water to appear more frequently near Antarctica. Rising temperatures. In short: A warming ocean spells disaster for our polar regions.
“Antarctica is melting away,” Rignot told CNN, “and not just in a couple of places.”
All that meltwater will have a big impact on the world’s oceans. The study upends a prevailing hypothesis that ice loss has been concentrated in western Antarctica, and that the East Antarctic Ice Sheet, which holds most of the continent’s ice, is stable overall. Researchers found East Antarctica’s contribution to sea level rise is more or less on par with that of the western half of the continent. The researchers conclude that if the climate continues to warm, these melting ice sheets could contribute to a rise in sea level that’s measured in meters, not inches.
“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,” Rignot concludes.