Arctic sea ice extent this year second lowest in 35 years: NSIDC

Arctic sea ice extent for March 2016 was 14.43 million square kilometres, The magenta line shows the 1981 to 2010 median extent for that month. (IMAGE/ NSIDC)

In March, Arctic sea ice extent fell to its second lowest extent since 1981 — as did the overall Arctic sea ice extent for 2016.

But that’s not all that makes 2016 memorable, according to the National Snow and Ice Data Center.

“Low Arctic sea ice extent for March caps a highly unusual winter in the Arctic,” the NSIDC said in an April 6 update.

Here’s how unusual the winter of 2016 was for ice and snow:

• Northern Hemisphere snow cover for both February and March was unusually low — March 2016 marked the 49th lowest out of 50 years on record in snow cover extent for the Northern Hemisphere.

“While April and May could still bring snow to the higher latitudes, we note that low snow cover, similar to low sea ice cover, leads to greater heat absorption by the surface in the Arctic and further warming as we move toward summer,” the NSIDC said.

• March of 2016 saw unusually warm conditions over nearly all of the Arctic Ocean — the warmth for March of 2016 continued with the above-average temperatures for most of the Arctic and much of the Northern Hemisphere during the winter. There was persistent warmth in the atmosphere, with temperatures two to 14 degrees Celsius above average, that helped to limit ice growth.

“As an exclamation point on the unusual warmth, there was a brief weather event at the very end of December 2015 when air temperatures near the Pole nearly reached the melting point,” the NSIDC said.

• Ice continued to get thinner and younger.

“The bottom line is that ice no longer survives in the Arctic for very long. It is lasting three to four years tops… This is a big change from the past when much of the ice cover would survive upwards of a decade,” the NSIDC said.

To better understand what’s going on with sea ice, there are plans to mount a year-long, international project, called Mosaic, from the autumn of 2018 to the autumn of 2019 in the Arctic Ocean.

This would see the Polarstern, a science-equipped icebreaker drifting across the Arctic Ocean, collect information during its journey.