Measuring the volume of the ice is a different measure than the percentage of ocean covered with ice. And this growth in volume was unexpected (of course):
In October 2013, the European Space Agency satellite CryoSat measured 9,000 cubic kilometres of sea ice on the Arctic Ocean, said an ESA news release Monday. At the same time of year in 2012, it measured just 6,000 cubic kilometres — a record low.
The satellite, launched in 2010, is designed to measure sea ice thickness across the Arctic Ocean, allowing scientists to monitor changes in volume and not just surface coverage.
[. . .]
Scientists had noticed that generally, since CryoSat was launched in 2010, Arctic sea ice volumes haven’t varied as much from year-to-year as sea ice coverage.
Because of that, they hadn’t expected an increase in volume comparable to the increase in surface coverage, said Rachel Tilling, lead author of the new study, in a statement.
“But it has been, and the reason is related to the amount of multi-year ice in the Arctic,” added Tilling, a researcher at the U.K.’s Centre for Polar Observation and Modelling.
Multi-year ice survives more than one summer without melting and is considered an indicator of “healthy” Arctic sea ice cover, the ESA reported.
But we know the conclusion before they say it:
“The Arctic caught a break, if you will, in 2013,” said Martin Jefferies, the University of Alaska geophysicist who edited the report card, at the AGU conference. “But one year doesn’t change the long-term trend toward a warmer Arctic.”
We’re still doomed.