Long-Term Stratospheric Ozone Changes and Associated Climate Impacts in CMIP6 Simulations

Stratospheric ozone depletion plays a prominent role in Southern Hemisphere climate change, with impacts on tropospheric circulation and surface climate in austral summer. For future projections, the interplay between stratospheric ozone recovery from a decrease of ozone-depleting substances and increasing greenhouse gases could in addition have important long-term implications for CO₂ uptake in the Southern Ocean and changes to Antarctic ice sheets.

More and more simulations from the Coupled Model Intercomparison Project Phase 6 (CMIP6) are now becoming available, with some models representing a new generation of Earth System Models, which will allow for unprecedented analyses of ozone changes on the coupled Earth System. We examine stratospheric ozone, and also partial ozone columns, and associated climate impacts over the historical (1960-2014) and future (2015-2100) period under varying greenhouse gas and halogen concentrations in a multi-model assessment. First, the historical CMIP6 ozone simulations are evaluated against observations, then the CMIP6 ozone projections are assessed, and prominent features of associated climate impacts are highlighted.