Efforts to heal hole in ozone layer also helped Arctic sea ice, study suggests

The Montreal Protocol was a significant international effort that unfolded after the discovery of a hole developing in the ozone layer above Antarctica. He said although policy makers probably weren’t thinking about Arctic sea ice when the protocol was signed, it does carry lessons for changing the course of a warming planet. Only after a couple years of finding out about the development of the ozone hole, the international community took action,” he said. But he said the main result — that the Montreal Protocol is delaying an ice-free Arctic summer — is “robust” and he expected others would come to the same conclusion. “When we correct for that underestimation, we get steeper declining trends in the future, and an earlier projected day of an ice-free Arctic,” Gillett said.