Arctic sea ice maximum hits another record

For the third straight year the winter maximum extent of the Arctic sea ice cover has reached its lowest ever level, the National Snow and Ice Data Center announced March 22.

Following the winter freeze up, on March 7 the sea ice extent reached 5.57 million square miles before starting to decline as the annual melt season began. The resulting maximum extent was the lowest recorded in the 28 years since satellite observations of the ice began. By comparison, the maximum extent in 2015 was 5.605 million square miles, while in 2016 it was 5.606 million square miles, NSIDC said.

NSIDC attributes the low extent, in part, to exceptionally warm autumn and winter weather, with air temperatures 4.5 degrees F above average across the Arctic Ocean. In particular, a series of extreme winter heat waves impacted the region, in a similar manner to what happened in the winter of 2015.

“I have been looking at Arctic weather patterns for 35 years and have never seen anything close to what we’ve experienced these past two winters,” commented Mark Serreze, NSIDC director.

Satellite data also indicates that this winter’s sea ice has been slightly thinner than has been the case in the past four years. As a consequence the total volume of sea ice is unusually low - assessments of sea ice conditions need to consider both the extent and the thickness of the ice, especially given the fact that thick multiyear ice tends to be more durable than young, thin ice.

“Such thin ice going into the melt season sets us up for the possibility of record low sea ice conditions this September,” commented NSIDC scientist Julienne Stroeve.

- ALAN BAILEY