Disappearing landscapes: The Arctic at +2.7°C global warming

Under current nationally determined contributions (NDCs) to mitigate greenhouse gas emissions, global warming is projected to reach 2.7°C above preindustrial levels. In this review, we show that at such a level of warming, the Arctic would be transformed beyond contemporary recognition: Virtually every day of the year would have air temperatures higher than preindustrial extremes, the Arctic Ocean would be essentially ice free for several months in summer, the area of Greenland that reaches melting temperatures for at least a month would roughly quadruple, and the area of permafrost would be roughly half of what it was in preindustrial times. These geophysical changes go along with widespread ecosystem disruptions and infrastructure damage, which, as we show here, could be substantially reduced by increased efforts to limit global warming.