Too late to save summer Arctic ice, new research shows
Analysis shows that even if greenhouse gas emissions are sharply reduced, the Arctic will be ice-free in September in coming decades.
It is now too late to save summer Arctic sea ice, new research shows.
Scientists say preparations need to be made for the increased extreme weather across the northern hemisphere that is likely to occur as a result.
Analysis shows that even if greenhouse gas emissions are sharply reduced, the Arctic will be ice-free in September in coming decades. The study also shows that if emissions decline slowly or continue to rise, the first ice-free summer could be in the 2030s, a decade earlier than previous projections.
The research shows 90% of the melting is caused by human-caused global heating, with natural factors accounting for the rest.
Since satellite records began in 1979, summer Arctic ice has shrunk by 13% a decade, in one of the clearest signs of the climate crisis. Arctic sea ice reaches its annual minimum at the end of summer, in September, and in 2021 it was at its second lowest extent on record.
"Unfortunately it has become too late to save Arctic summer sea ice,” said Professor Dirk Notz, of the University of Hamburg, Germany, who was part of the study team.
“As scientists, we’ve been warning about the loss of Arctic summer sea ice for decades. This is now the first major component of the Earth system that we are going to lose because of global warming.
“This brings another warning bell, that the kind of projections that we’ve made for other components of the Earth system will start unfolding in the decades to come.”
Other climate scientists said in 2022 that the world was on the brink of multiple disastrous tipping points.
Professor Seung Ki Min, of Pohang University, South Korea, who led the new study, said: "The most important impact for human society will be the increase in weather extremes that we are experiencing now, such as heatwaves, wildfires and floods. We need to reduce CO2 emissions more ambitiously, and also prepare to adapt to this faster Arctic warming and its impacts on human society and ecosystems."
In 2021, the Intergovernmental Panel on Climate Change (IPCC) concluded that the Arctic would not lose its summer ice if emissions were cut sharply and global temperature rises were limited to 2C. But the new research, published in the journal Nature Communications, projects the loss of summer sea ice in the 2050s in the low emissions scenario.
The IPCC report concluded the Arctic would lose its summer ice in the 2040s in intermediate and high emissions scenarios, but the new research advances that by a decade into the 2030s.
In the study, the scientists first established how much rising greenhouse gases have contributed to ice melting compared with natural factors such as variation in the sun’s intensity and emissions from volcanoes.
“Humans really are to blame for almost all the loss of Arctic sea ice we have been observing,” Notz said.
The scientists used this information to model future melting and found the models underestimated the pace of melting compared with observations of ice in the Arctic from 1979 to 2019.
Calibrating the models to be consistent with the observations led to the projections of faster melting and an ice-free summer even in the low-emissions scenario. In the intermediate- and high-emissions scenarios, August and October also become ice-free by about 2080, the study found.
• Guardian
CLIMATE & SUSTAINABILITY HUB
CONNECT WITH US TODAY
Be the first to know the latest news and updates
