Zoe Gillett: Evaluation of historical experiments with ACCESS-ESM1.6 for the CMIP7 Assessment Fast Track
The CMIP7 Assessment Fast Track is a targeted set of experiments designed for completion in time for inclusion in the next IPCC Assessment Report. ACCESS-ESM1.6 is Australia’s submission to this Fast Track. In this talk, we present an evaluation of the model’s historical simulations spanning 1850 to 2021. The CMIP7 historical runs incorporate eight years of updated observed forcings (2015-2021) that were previously part of the CMIP6 ScenarioMIP period. We compare ACCESS-ESM1.6 with observations and its CMIP6 predecessor, ACCESS-ESM1.5. An innovation in CMIP7 is the introduction of emissions-driven experiments, which are forced by fossil fuel carbon emissions. We also examine how these simulations compare with traditional concentration-driven historical runs. We assess the model’s mean state and key modes of variability across timescales from intraseasonal to decadal, and their associated teleconnections to precipitation and temperature, with a particular focus on Australian and broader Southern Hemisphere climate.