Arctic winter ends with lowest sea ice cover in recorded history

Arctic sea ice had its weakest winter buildup since record-keeping began 47 years ago. It is a symptom of climate change that will have repercussions globally, scientists said Thursday.

The Arctic reaches its maximum sea ice in March each year and then starts a six-month melt season. The National Snow and Ice Data Center said the peak measurement taken Saturday was 14.33 million square kilometres - about 80,000 square kilometres smaller than the lowest previous peak in 2017.

That's a difference about the size of California.

“Warming temperatures are what’s causing the ice to decline,'' ice data scientist Walt Meier said. “You know, sea ice in particular is very sensitive... 31 degrees is ice skating and 33 degrees it’s swimming.”

Jennifer Francis, a scientist at the Woodwell Climate Research Center in Cape Cod, said this is yet another ringing alarm bell in the form of a broken record.

“Disappearing sea ice is a particularly worrisome story because it’s truly an early warning system alerting us about a variety of hard-to-see changes,” Francis said in an email.

Scientists said warming conditions in the Arctic - the region is warming four times faster than the rest of the world - affect weather elsewhere. Pressure and temperature differences between north and south shrink. That weakens the jet stream, which moves weather systems along, making it dip further south with cold outbreaks and storms that often get stuck and rain or snow more, according to the snow and ice centre and Francis.

“The warming winter atmosphere above the Arctic Circle does impact large-scale weather patterns that do influence for those of us outside the Arctic,” said Julienne Stroeve, an ice scientist at the University of Manitoba.

Of the smaller sea ice,