NASA reveals that Antarctica is actually gaining more ice than it is losing. The surprising find shows that despite fears over global warming, Antarctica’s ice fields are growing faster than they are shrinking. The snow accumulation began 10,000 years ago and is adding enough ice to the southernmost continent to offset the increased losses from neighboring, thinning glaciers.
While known and monitored glaciers are shrinking because of global warming, the new study published in the Journal of Glaciology shows that recent ice gains at other glaciers more than offset the ice losses of the monitored ice fields. “We see an ice gain that exceeds the losses in the other areas,” affirms Jay Zwally, NASA Goddard Space Flight Center spokesperson and study author.
“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,” he says. “Our main disagreement is for East Antarctica and the interior of West Antarctic, there, we see an ice gain that exceeds the losses in the other areas,” added Zwally.
Measuring ice in Antarctica is a challenging task. Ice gain or loss is normally measured by tracking elevation changes. Changes in the elevation of ice across the Antarctic ice sheet is measured using primarily laser and also radar altimetry. Scientists have previously wrongly attributed gains in elevations in East Antarctica to recent snowfall due to the use of lasers and satellite altimetry to measure ice gain.
Lasers and sensors measure distances from the satellite to the ice surface. Radar altimeter signals provide very good coverage for ice sheets but have difficulty in accurately measuring sloped and rough terrain, due to some of the satellites’ outdated, low resolution equipment. The low resolution shortfall also makes it difficult to measure smaller glaciers where much of the ice loss in Antarctica occurs.
To avoid error this time, The NASA team led by Zwally used data from 1979 to prove most accurately that the ice cores in the area have actually been thickening, making the study’s findings of ice gain promising.
The findings challenge previous research by the United Nations Intergovernmental Panel on Climate Change’s findings that Antarctica is losing land ice overall and is set to flood coastal cities around the globe. Its 2013 study had concluded that the sea is rising by 0.27 millimeters annually because of the ice melting in Antarctica.
But coastal cities are not out of danger yet. According to Zwally: “The good news is that Antarctica is not currently contributing to sea level rise, but is taking 0.23 millimeters per year away,” he said. “But this is also 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.”