A study suggests that the Arctic "may be essentially ice-free during summer within 15 years."
The study used statistical models to predict the future amount of Arctic ice, which suggested that the Arctic could be ice-free in the summer during the decade of the 2030s – most likely in the year 2034.
Sea ice is frozen ocean water that melts each summer, then refreezes each winter. The amount of summer sea ice in the Arctic has been steadily shrinking over the past few decades because of global warming. It reached its second-smallest level on record in 2019, the National Oceanic and Atmospheric Administration (NOAA) said.
Sea ice affects Arctic communities and wildlife such as polar bears and walruses, and it helps regulate the planet’s temperature by influencing the circulation of the atmosphere and ocean.
walrus[ˈwɔːlrəs]: n. 海象
"The extent of Arctic ice is important to Arctic peoples, whose lands are being affected by increased coastal erosion," NOAA said in a statement. "Conversely, the disappearance of ice creates economic opportunities, including the opening of oil fields and new shipping routes."
It also affects global weather patterns.
The study was conducted by scientists at NOAA, the University of Washington, and the North Carolina Institute for Climate Studies.
What scientists refer to as the first "ice-free" Arctic summer year will occur when the Arctic has less than 1 million square kilometers of sea ice. The thick ice sheets surrounding Canada’s Arctic islands are likely to remain for much longer, even in summer.
As the climate changes, the Arctic is warming more than twice as fast as the rest of the planet. Arctic air temperatures were about 3.4 degrees above average in 2019, and were the second-warmest since records began in 1900.
Scientists also said the results of the study indicate that there is room for improvement in sea-ice models – and that the ice may disappear even more quickly than current models suggest.
"Climate models may be collectively underestimating the rate of change,” the authors write in the study.
The study was published in the journal Climate.