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Projected First Ice-Free Day in the Arctic Could Occur by 2027

A historic shift in the state of the Arctic may be on the horizon, with forecasts suggesting that the first summer devoid of nearly all sea ice could take place as soon as 2027.

An international research initiative, featuring contributions from climatologists such as Alexandra Jahn of the University of Colorado Boulder and Céline Heuzé from the University of Gothenburg, has employed advanced computer modeling techniques to predict when the first ice-free day might happen in the Arctic Ocean. The repercussions of an ice-free Arctic could reverberate throughout Earth’s ecosystems and climate, potentially altering weather patterns significantly.

“While the occurrence of the first ice-free day won’t bring about immediate dramatic changes, it will signify a fundamental alteration in one of the Arctic Ocean’s defining traits—its year-round ice and snow coverage,” stated Jahn, who serves as an associate professor in the Department of Atmospheric and Oceanic Sciences and is also affiliated with CU Boulder’s Institute of Arctic and Alpine Research. “This change is primarily driven by greenhouse gas emissions.”

The results of this study were shared in the journal Nature Communications on December 3, and Jahn is set to present these findings on December 9 at the American Geophysical Union’s annual meeting in Washington D.C.

A Blue Arctic

The Arctic is undergoing rapid transformation due to climate change, with sea ice diminishing at a concerning rate of over 12% per decade. Data released in September by the National Snow and Ice Data Center revealed that the minimum extent of Arctic sea ice this year reached historically low levels since records began in 1978.

At 1.65 million square miles (approximately 4.28 million square kilometers), this year’s minimum, while higher than the record low set in September 2012, still illustrates a dramatic reduction from an average sea ice extent of 6.85 million square kilometers recorded between 1979 and 1992.

Experts consider the Arctic to be ice-free if the extent drops below 1 million square kilometers. Previous studies predicting the loss of sea ice had primarily concentrated on identifying when the Arctic Ocean would be ice-free for an entire month; however, Jahn’s research now emphasizes the potential for a single ice-free day to occur earlier, potentially before the 2030s.

“Understanding when the first ice-free day could arise is crucial for preparation,” noted Heuzé. “It’s essential to identify the events that could precipitate a complete sea ice melt in the Arctic Ocean.”

Non-Zero Possibility

Utilizing data from over 300 computer simulations, the researchers estimated the likelihood of an ice-free day in the Arctic. Their findings suggest that most models anticipate this event could take place between nine and 20 years after 2023, irrespective of human efforts to curb greenhouse gas emissions. In some extreme scenarios presented in the simulations, the earliest instance of an ice-free day might materialize within a mere three years.

Such outcomes, while extreme, are plausible based on simulation results, with nine scenarios indicating the possibility of an ice-free day occurring within three to six years. The research indicates that a combination of severe weather phenomena, such as an unusually warm autumn weakening the ice followed by a mild Arctic winter and spring, could result in significant ice loss. When this pattern persists for three consecutive years, the likelihood of an ice-free day in late summer increases.

Evidence of such warming patterns has already emerged; for instance, in March 2022, parts of the Arctic were recorded as being 50°F warmer than average, surrounding areas near the North Pole showed signs of melting. According to Heuzé, the intensity and frequency of such extreme weather events are projected to rise due to ongoing climate change.

The presence of sea ice is vital for regulating temperatures in the Arctic by reflecting sunlight back into space. A decrease in ice coverage means that darker ocean waters will absorb more solar heat, further exacerbating temperature increases in both the Arctic region and globally. Additionally, warming in the Arctic has the potential to disrupt wind and ocean current patterns, resulting in more pronounced extreme weather events worldwide.

Amid these alarming projections, there is a silver lining: significant reductions in greenhouse gas emissions could extend the timeline for an ice-free Arctic and shorten the duration of such conditions. “Mitigating emissions will be crucial to preserving sea ice,” emphasized Jahn.

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