Nature, 18 October 2023
New research suggests that the Greenland Ice Sheet may be slightly more resistant to global warming than previously thought, with complete loss occurring if global temperatures stabilize between 1.7-2.3°C (median 2.1°C), rather than median 1.6°C as in previous studies. It also found that reducing greenhouse gas concentrations in the atmosphere as quickly as possible, to below 1.5°C, could prevent Greenland’s reaching a threshold for irreversible loss, by keeping the height of the ice sheet at sufficient altitude that it remains below freezing. The authors caution however that their results are based on two ice sheet models that do not consider ice-ocean interactions (see above study) and/or small-scale processes, so these projections contain substantial uncertainty, with complete melting and sea level rise likely set to occur faster and at lower temperatures than estimated above. “The higher temperatures rise, the more difficult it will be to bring them down to safe levels in the long term. This is why we need to act fast and keep global mean temperatures below 1.5°C,” concluded co-author Dr. Niklas Boers, Potsdam Institute for Climate Impact Research.