Devising storylines of Arctic climate change from a large ensemble of CMIP6 models

While polar amplification has been established as a defining feature of Arctic climate change, poor quantitative agreement among models remains when assessing its magnitude and spatial pattern. Here, we apply the storyline approach to a large ensemble of CMIP6 models, with the aim of distilling the wide spread in model predictions into four physically plausible outcomes of Arctic climate change. This is made possible by leveraging strong covariability in the climate system: specifically, we find that differences in Barents Sea warming and lower tropospheric warming among CMIP6 models explain most of the intermodel variability in pan-Arctic surface climate response to global warming. Based on this novel finding, we compare regional disparities in climate change across the four storylines, and discuss potential implications for modeling climate change impacts on ecosystems and human activities.