Abstract In the present study, production and loss pathways of tropospheric ozone and their rates are identified by an algorithm for the automatic determination of reaction pathways in complex chemical systems. For this purpose, reaction rates were provided by the chemistry-transport model IFS(MOZART) (Integrated Forecasting System - Model for Ozone and Related chemical Tracers). A detailed analysis is carried out for three different scenarios: clean air (Palau), intermediate emissions (Athens),