The Arctic could be ice-free by summer 2027: What it means for weather, shipping and polar bears

While most projections of the Arctic’s sea ice have focused on month-by-month conditions, a new study has revealed possible predictions down to the day.

Previous expectations had the Arctic Sea loss predicted around 2030, but these results reveal that an ice-free day could occur as early as late summer 2027. 

Nine other simulations, while less likely, predict that it could occur within the next three to six years.

Scientists, from the study published in Nature Communications, say the Arctic’s first ice-free day is now inevitable and irreversible, regardless of how humans alter greenhouse gas emissions.

What is an ice-free Arctic, and why does it matter?

The Arctic Ocean covers a vast area of more than 16 million square kilometres, and for thousands of years, it has witnessed a natural seasonal event: layers of frozen seawater dramatically build up over the winter months into a thick ice cap that peaks in March before it melts in September. 

In recent decades, however, this dramatic event has been less prevalent. 

Sea ice has declined by more than 12 per cent every decade since 1978, when satellite imagery - the Scanning Multichannel Microwave Radiometer or ‘SMMR’ - started recording Arctic sea ice growth and retreat.

That’s 80,000 square kilometres every year - roughly the same size as Austria or the Czech Republic. 

Scientists define ‘ice-free’ as the sea ice area dropping to less than one million square kilometres in a short time, which is considered a climate tipping point. 

A team of international researchers, including climatologist Alexandra Jahn from the University of Colorado Boulder and Céline Heuzé from the University of Gothenburg in Sweden, used over 300 computer models to predict the first ice-free day. These showed an accelerated timeline compared to what was previously projected. 

Rapid ice loss events are typically associated with intense winters and spring warming. 

Long-term, if the Arctic Ocean is regularly declared ice-free, this could significantly impact the fragile ecosystem of the northernmost sea, including everything from the ‘emblematic polar bear to the crucial zooplankton,’ the study reveals. 

What will the Arctic Ocean’s ice-free days mean for humans?

The day the Arctic shows ice-free conditions is symbolically significant. It will visually highlight how humans have changed one of our planet's defining natural features: from a white to a blue Arctic Ocean.

“The first ice-free day in the Arctic won’t change things dramatically,” explained Jahn in a statement.

“But it will show that we’ve fundamentally altered one of the defining characteristics of the natural environment in the Arctic Ocean, which is that it is covered by sea ice and snow year-round, through greenhouse gas emissions.”

The sun never sets in the Arctic during summer, so without the reflective ice reflecting sunlight into space, the ocean will absorb and distribute a substantial amount of heat around the Earth. 

International waters do not have any jurisdiction, so commercial industries could exploit opportunities found in the warmer Arctic waters. They could fish and deep-mine previously inaccessible marine and mineral populations, while freight companies could take a quicker shipping route across the Northwest Passage.

The warming could also lead to more erratic and extreme weather events through changing wind and ocean current patterns. 

Warmer years have already occurred: in March 2222, some of the Arctic was 50F/10C warmer than the average, which caused areas around the North Pole to almost melt.

The study's authors say there is still a chance to delay the timeline for the sea ice melt in the near future. 

"Any reductions in emissions would help preserve sea ice," added Jahn.