A new NASA study published in the December 2015 Journal of Glaciology showed that Antarctica is adding more ice than it’s been losing. This finding challenges other research, including the UN’s Intergovernmental Panel on Climate Change, that concluded that Earth’s southernmost frozen continent is losing more land ice than not. NASA’s new paper shows it isn’t.
The paper, published by researchers from NASA’s Goddard Space Flight Center, the University of Maryland in College Park, and the engineering firm Sigma Space Corporation show that based on satellite data, there was a “net gain of 112 billion tons of ice a year from 1992 to 2001 in the Antarctic ice sheet. The gain slowed to 82 billion tons of ice per year between 2003 and 2008. All of which translates to a net reduction in global sea level rise of 0.23 mm per year.”
The study authors say in a NASA announcement that the findings “challenge current explanations for sea level rise, much of which is attributed to Greenland and Antarctica. The good news is that Antarctica is not currently contributing to sea level rise, but is taking 0.23 millimeters per year away,” said Dr. Zwally.
According to Zwally, “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.” The researchers measured the ice gain by “looking at the height of the Antarctic ice sheet as measured by radar instruments on two European Space Agency satellites from 1992 to 2001, and by laser sensors on a NASA satellite from 2003 to 2008.”
Zwally’s team used “meteorological data dating back to 1979 to show that the snow accumulation in East Antarctica has actually been declining, showing that the increase in elevation must be the result of thicker ice.” That’s because at the end of the last inter-glacier period about 10,000 years ago, “warmer air carried moisture across the continent, doubling the amount of snowfall that has been accumulating.” This accumulated snow eventually turns into compacted solid ice.
Other studies show that both Arctic and Greenland ice is freezing at historical levels, as reported by other agencies around the world. This may explain why sea level rise hasn’t gone up higher than projected by the IPCC and other organizations. In fact, sea level rise has remained constant over the last two centuries.
In May we reported that ice has become such a problem, that Rob Wooding, the operations manager of the Australian Antarctic Division, told the media that growing ice around Antarctica is creating ‘serious problems’ for scientists studying the continent. With ice not melting/weakening between seasons, seafaring vessels carrying much-needed supplies are unable to break through the ice and get to the research stations.
Tags: Antarctic Ice Sheet