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The polar bear has to make do with less and less ice in the summer months
Photo: Wolfgang Kaehler / LightRocket / Getty Images
Due to climate change, there could be more and more ice-free summer days in the Arctic within the next decade.
Between 2035 and 2067, an ice-free September can even be expected to become the norm, according to a study published in the journal Nature Reviews Earth & Environment.
The study authors date the first ice-free day in the Arctic more than ten years earlier than previous forecasts.
In the study, “ice-free” means coverage of less than one million square kilometers.
In this case, the Arctic would consist largely of water; it is then referred to as a “blue Arctic”.
“Such changes have most likely not occurred for at least 80,000 years,” says the study, whose authors conduct research at the US University of Colorado Boulder.
Exactly when there will be an ice-free Arctic and how long the periods of time in which the region will have little ice cover will depend on global emissions of climate-damaging greenhouse gases in the next few years, according to the specialist team.
By the end of the century there was a risk of ice-free conditions from May to January if emissions remained high, but ice-free conditions between August and October with lower CO₂ emissions than currently.
According to the calculations, there is no scenario without ice-free conditions.
Dramatic consequences of a “blue Arctic”
The major thaw in summer particularly affects the habitat of polar bears, seals and walruses.
These then have an extremely shrunken territory in which they live and hunt.
In addition, the climate crisis could become even worse due to the seasonal melting of the Arctic.
If there are fewer white areas at the poles, the radiation balance changes and the so-called albedo effect is reduced.
When ice and snow, which normally reflect sunlight, melted into seawater, the dark water absorbed the sunlight's heat and warmed up.
As a result, even more ice thaws or it only freezes with a delay in autumn, the darker surface increases, a vicious circle.
In addition, an ice-free Arctic also threatens the coasts, the authors write, because waves become larger and cause more erosion.
The researchers also expect better accessibility to the Arctic for ships and for mining raw materials.
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