Study suggests Arctic sea ice loss not irreversible



The Arctic has been losing sea ice as Earth's climate warms, and some studies have suggested that the Arctic could reach a tipping point, beyond which ice would not recover even if global temperatures cooled down again. However, a new study byArmour et al. that uses a state-of-the-art atmosphere-ocean global climate model found no evidence of such irreversibility. In their simulations, the researchers increased atmospheric carbon dioxide levels until Arctic sea ice disappeared year-round and then watched what happened as global temperatures were then decreased. They found that sea ice steadily recovered as global temperatures dropped. An implication of this result is that future sea ice loss will occur only as long as global temperatures continue to rise. (Geophysical Research Letters, doi:10.1029/2011GL048739, 2011)