August 12, 2012

CryoSat-2 Finds Arctic Ice Melting Faster Than Previously Expected

redOrbit Staff & Wire Reports - Your Universe Online

Arctic sea ice is melting away far more rapidly than experts had previously predicted, with more than 215 cubic miles (900 cubic kilometers) worth disappearing from the Arctic Ocean over the past year, according to information obtained by the European Space Agency's CryoSat-2 probe.

According to Robin McKie, Science Editor with the UK newspaper The Guardian, that constitutes a 50% higher rate of loss than the majority of predictions from polar science experts.

CryoSat's findings illustrate that increases in greenhouse gas emissions and the resulting changes in climate have already started to have a "major impact" on the area, and could mean that the ocean could be ice-free during the summer in just a few years' time.

Scientists had already learned from other satellites that the summer sea ice in the Arctic had been "dwindling rapidly," McKie said. However, these new findings suggest that it has also been "thinning dramatically at the same time."

"Preliminary analysis of our data indicates that the rate of loss of sea ice volume in summer in the Arctic may be far larger than we had previously suspected," Dr. Seymour Laxon, who works studying the satellite's data at the Centre for Polar Observation and Modelling at University College London (UCL), told the Guardian. "Very soon we may experience the iconic moment when, one day in the summer, we look at satellite images and see no sea ice coverage in the Arctic, just open water."

"The consequences of losing the Arctic's ice coverage, even for only part of the year, could be profound," the Guardian Science Editor explained. "Without the cap's white brilliance to reflect sunlight back into space, the region will heat up even more than at present. As a result, ocean temperatures will rise and methane deposits on the ocean floor could melt, evaporate and bubble into the atmosphere."

Experts have already discovered evidence that methane plumes have been appearing in several areas, and the increased presence of this powerful greenhouse gas could well speed-up the effects of global warming, McKie added.

Furthermore, UCL Professor Chris Rapley told her that the dropping temperature gradient between the Arctic region and the equator could make the upper atmosphere jet stream less stable, leading to more volatile weather in the lower latitudes.

CryoSat-2 was launched on April 8, 2010, and is currently traveling around the Earth in a highly inclined polar orbit, reaching latitudes of 88 degrees north and south in order to maximize coverage of both poles, the ESA said on the satellite's official website. It's primary payload, the Synthetic Aperture Interferometric Radar Altimeter (SIRAL), is the first instrument of its kind specifically designed for ice, they added.