The ice covering the Arctic Ocean is shrinking year after year due to climate change. It could completely disappear for the first time, even if only for a day, as early as 2027. This is the conclusion of a study published on Tuesday, December 3rd, in the journal Nature Communications by researchers from the University of Gothenburg (Sweden) and the University of Colorado (United States).
Specifically, the scientists define the Arctic Ocean as « ice-free » when the ice extends over less than one million square kilometers in total. Each year, the sea ice grows during the winter and melts during the summer, reaching its minimum extent in September. This minimum extent has been shrinking dramatically: by an average of 12% per decade, according to NASA satellite observations. In recent years, the minimum extent was around four million square kilometers.
In 2023, the same researchers had already estimated that the Arctic could experience its first completely ice-free month by 2035. In their new numerical simulations, the authors estimate that the first ice-free day has the highest probability of occurring within 7 to 20 years.
However, in the most extreme scenarios — 9 simulations out of 366 — the event could occur as early as 2027. Most concerning is that this early occurrence could happen regardless of future carbon emissions scenarios.
In other words, the probability of this happening so soon is low, but it depends primarily on the internal variability of the climate, which involves unpredictable variations. Several extremely hot consecutive years in the region, along with the occurrence of storms, could under certain conditions be sufficient to eliminate the ice.
The first ice-free day will be mostly symbolic, the researchers note. It will not, by itself, signal the triggering of a climate tipping point but underscores our proximity to that risk. The only way to weaken these probabilities is to drastically reduce our greenhouse gas emissions, the authors remind us.
