That's a preliminary finding by researchers at the National Snow and Ice Data Center in Boulder, Colo., who say the summer minimum has passed and the ice has entered its winter growth phase, the BBC reported Wednesday.
At its smallest extent on Sept. 10, 1.84 million square miles of Arctic Ocean was covered with ice, more than in 2007 and 2008 but less than in every other year since 1979, scientists say.
The ice had melted unusually fast, researchers say.
"It was a short melt season -- the period from the maximum to the minimum was shorter than we've had -- but the ice was so thin that even so it melted away quickly," NSIDC researcher Walt Meier told the BBC.
NASA data show the last 12 months have been unusually warm globally, the warmest in 130 years of record keeping, the agency said.
Nevertheless, projections of complete disappearance of arctic ice very soon seem to have been too extreme, Meier said.
"But the 2040/2050 figure that's been quoted a lot -- that's still on track. It could end up being wrong, of course, but the data we have don't disprove it."