COVID-19 induced lower-tropospheric ozone changes

Abstract The recent COVID-19 pandemic with its countermeasures, e.g. lock-downs, resulted in decreases emissions of various trace gases. Here we investigate the changes ozone over Europe associated these emission reductions using a coupled global/regional chemistry climate model. We conducted and analysed business as usual sensitivity (COVID19) simulation. A source apportionment (tagging) technique allows us to make sector-wise attribution changes, natural anthropogenic sectors such land transport. Our simulation results show decrease 8% May 2020 due reductions. simulated are line observed ground-level ozone. that this is mainly decreased precursors from origin. Further, our reduction much smaller than total NO x (around 20%), caused by an increased production efficiency. This means more produced for each emitted molecule. Hence, formed productivities remaining increase. politically induced cannot be transferred directly reductions, which needs considered when designing mitigation strategies.