Ice-free Arctic summers now inevitable, say scientists

New research suggests that it is now inevitable that the Arctic will become ice-free in summer, irrespective of any efforts made to reduce greenhouse gas emissions.

This, scientists say, is likely to result in increased extreme weather across the Northern Hemisphere – something humans will now have to prepare for.

The study, published in the journal Nature Communications, shows that 90% of the melting is a result of climatic warming driven by human activities. Analysis shows that even if emissions are sharply reduced in the coming years, the Arctic will be ice-free in September in the coming decades. Alarmingly, this could be as soon as the 2030s if emissions decline slowly or continue to rise.

The Arctic could be ice-free in summer by the 2030s, according to the new research (Paul Gierszewski / commons.wikimedia.org).

The summer extent of Arctic ice has been declining at some 13% per decade since satellite records began in 1979. It is in September that sea ice is at its minimum extent.

The Intergovernmental Panel on Climate Change's (IPCC) 2021 report concluded that the Arctic would not lose its summer ice if emissions were cut sharply and global temperature rises were limited to 2°C. But the new research suggests that summer sea ice will be lost in the 2050s in the low emissions scenario.

"Unfortunately it has become too late to save Arctic summer sea ice," said Prof 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. People didn't listen to our warnings.

"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."

Reference

Kim, Y-H, M, S-K, Gillett, N P, Notz, D, & Malinina, E. 2023. Observationally-constrained projections of an ice-free Arctic even under a low emission scenario. Nature Communications. DOI: https://doi.org/10.1038/s41467-023-38511-8