Tropospheric ozone budget in AerChemMIP experiments

A grand challenge in the field of chemistry-climate modelling is to understand the connection between anthropogenic emissions, atmospheric composition and the radiative forcing of trace gases and aerosols.  The AerChemMIP model intercomparison project, part of CMIP6, aims to understand the role of near-term climate forcers, aerosol and chemistry and includes experiments focused on tropospheric ozone.

We present an analysis of the trends in tropospheric ozone budget in the UKESM1 and other models for which diagnostic data is available from CMIP6 experiments. We focus on the historical period, and evaluate trends in ozone budget terms of chemical production and loss of ozone as well as physical processes such as transport and deposition.  We include AerChemMIP attribution experiments such as histSST-piCH4, to quantify the effect of individual emissions and forcing changes on the historical ozone burden and budget.  We include a comparison of ozone budget over ocean basins with data from recent ATom field campaigns.