Arctic Ocean could have 1st day without sea ice by 2027, study says

Within three years, the Arctic Ocean could have its first summer without sea ice.

That's according to a study published in the journal Nature Communications this week. Researchers used more than 300 computer models to predict when the Arctic Ocean could have its first ice-free day.

In a worst-case scenario, that could happen in 2027.

Alexandra Jahn is with the University of Colorado Boulder's department of atmospheric and oceanic sciences, and is one of the researchers behind the study. One ice-free day won't be catastrophic, she said, but it serves as a stark warning. 

"That will be the first time we will see a practically ice-free Arctic Ocean from space in the satellite observations," she said.

By ice-free, they mean when the ocean has less than one million square kilometres of ice. 

She explains there's a large swath of ice that's harder to melt, mostly in northern Nunavut and Greenland, which is often known as the last sea ice area. But that final bastion of the Arctic might not hold if global warming exceeds 2 C. 

That area includes the Tuvaijuittuq Marine Protected Area, where the federal government has extended an interim protection order on tourism for another five years.

The researchers based their projections on September 2023 equivalent conditions, which had roughly 3.39 million square kilometres of sea ice. 

Compared to previous years, later annual freezes in the Arctic Ocean are already happening, leading to more patches of open water. 

"This open water has a much darker surface and absorbs more of the incoming solar radiation throughout the summer," Jahn said.

Professor Bruno Tremblay is with McGill University's department of atmospheric and oceanic sciences. He wasn't involved in the study, but is also conducting similar research. 

Both he, and the study's authors, say nothing is certain.

Future emissions, and the effects storms can have on ice packs, can be hard to predict.