As cold weather dips down into Southcentral Alaska, word comes that the Arctic Ocean has begun freezing up. The sea ice low was hit on Friday the 13th of September, according to a press release today from the National Snow and Ice Data Center.
The ice stopped melting back and began refreezing when it still covered 1.97 million square miles of the Arctic Ocean late last week – much more ice than last year’s record low of 1.32 million.
National Snow and Ice Data Center head Mark Serezze says the ice cover is still on a downward trend compared to the average of 2.4 million between 1981 and 2010.
“It was still a very low year compared to the longer term record,” Serezze said. “It was just considerably higher than last year.”
And that is a relief. But this ice is thin; it was protected from the sun by a lot of cloud cover. Scientists are not forecasting any sort of reversal of the long term decline toward ice-free summers, for a number of reasons.
“When we say we had a recovery this year, you have to put this in a little bit of context, and take it with a grain of salt,” Serezze said.
There’s a new European Union satellite that can sense ice thickness. While it hasn’t been up long enough to make comparisons between years yet, it is showing the thinness of this summer’s ice, due in part, Serezze says, to storms.
“Also with this stormier pattern you kind of spread the ice out a little bit more, and that’s why we saw big areas of really a lot of open water, low concentration ice very, very far up in the pack this year, even near the North Pole,” Serezze said.
Last year after the record melt-back, the ice was so thin that a January storm spread a pattern of huge leads of open water across the Beaufort Sea in the dead of winter. This time there is 650,000 square miles more ice than last year going into freeze-up and much of that will become thicker, multi-year ice:
“By definition, the fact that we ended up with some more ice than we did last year means that that ice that survives now can maybe age through the winter,” Serezze said. “So, you know, could this be something that could increase our prospects for a little more recovery last year, maybe, but I wouldn’t hold my breath about it.”
Six years ago scientists were stunned at how far the sea ice melted back and some predicted it would be the new normal. This year’s withdrawal is in the high end of that range, but still within it.