The Arctic is experiencing a comeback in its sea ice, as its volume was recently measured to be 50 percent higher than at the same point in 2012.
According to BBC News, the European Space Agency's (ESA) Cryosat spacecraft calculated a total of 9,000 cu km of ice at the end of the Arctic's summer. This total would be nearly 50 percent higher than the end of the melting period in 2012.
In a time of heightened awareness for global warming and a rising global climate, the news can come as a surprise. Some experts said people should not invest too much in one year of ice volume recovery.
"Although the recovery of Arctic sea ice is certainly welcome news, it has to be considered against the backdrop of changes that have occurred over the last few decades," said Andy Shepherd, of University College London, U.K., told BBC News. "It's estimated that there were around 20,000 cu km of Arctic sea ice each October in the early 1980s, and so today's minimum still ranks among the lowest of the past 30 years."
Cryosat, the ESA's polar monitoring craft, has a radar system capable of measuring ice thickness as well as surface measurements. It recorded a record ice volume low in Oct. 2012, at 6,000 cu km. The latest arctic winter was especially cold and was a leading factor in the rise in ice volume. Not only did the winter help the arctic form new sea ice, but the frigid temperatures also retained old ice as well.
"One of the things we'd noticed in our data was that the volume of ice year-to-year was not varying anything like as much as the ice extent - at least for the years 2010, 2011 and 2012," explained Rachel Tilling from the U.K.'s Nerc Centre for Polar Observation and Modeling. "This is why we're really quite surprised by what we've seen in 2013."
Don Perovich, a sea-ice expert at Dartmouth College, told BBC News he agreed with Cryosat's recent data and said other satellite data backs up its findings.
"In previous summers, some of the [multi-year ice] migrated over to the Alaska and Siberia areas where it melted," he said. "But this past summer, it stayed in place because of a change in wind patterns. And so there'll likely be more multi-year ice next year than there was this year."