GRL - Modeling Forecasts Mult. Ice-Free Arctic Summers Before 2050; Ice-Free Arctic Winters Possible

The latest research suggests Arctic sea ice could disappear entirely in the summer sometime between now and 2050 even if the world is successful at substantially reducing greenhouse gas emissions. Even more alarming, some climate models predict a lack of Arctic sea ice even in winter, a development scientists say would be a catastrophe for animals that live in the Arctic. The study, published April 17 in the journal Geophysical Research Letters, begins with this “plain language summary.”

We examine simulations of Arctic sea ice from the latest generation of global climate models. We find that the observed evolution of Arctic sea‐ice area lies within the spread of model simulations. In particular, the latest generation of models performs better than models from previous generations at simulating the sea‐ice loss for a given amount of CO2 emissions and for a given amount of global warming. In most simulations, the Arctic Ocean becomes practically sea‐ice free (sea‐ice area < 1 million km2) in September for the first time before the year 2050.



“Alarmingly, the models repeatedly show the potential for ice-free summers in the Arctic Ocean before 2050, almost irrespective of the measures taken to mitigate the effects of climate change,” researcher Ed Blockley tells The Guardian. He is head of the UK Met Office’s polar climate program. “The signal is there in all possible futures. This was unexpected and is extremely worrying.” Prof Dirk Notz of the University of Hamburg helped coordinate the analysis. He says, “If we keep global warming below 2C, Arctic sea ice will nevertheless likely disappear occasionally in summer even before 2050. This really surprised us.”

The research employs the latest climate models from 21 research institutes. Unlike some political leaders who pretend to know everything there is to know about complex issues, climate scientists freely admit there are many unknowns in their research. “There is still a lot of uncertainty but all the models are clear that the sea ice will continue to decline. At some point, it will be gone, but when that happens is still uncertain. There are some models [in which the summer Arctic] goes ice-free in the next few years,” Blockley says, but cautions those are considered outlier scenarios.

EDIT

https://cleantechnica.com/2020/04/27/ice-free-arctic-coming-soon-to-a-country-near-you/