Considering Methane Emissions in the Modelling of Ozone Concentrations Using Chemical Transport Models

Methane is a greenhouse gas as well as a precursor to tropospheric ozone, an air pollutant that is harmful to our health and ecosystems. Global methane emissions, about one third of which originate in agriculture, contribute significantly to background levels of ground-level ozone. Although this connection has been understood for some time, the contribution of methane emissions to local exceedances of prescribed target values for ozone has received relatively little attention. As emissions of other anthropogenic ozone precursors such as NOx and VOCs continue to be reduced in Europe, increased attention may need to be given to methane as an ozone precursor in order to meet ozone air quality guidelines. Furthermore, global methane concentrations are rising, with this rise projected to continue under some emission scenarios, driven by increased extraction and the use of fossil fuels.

How well do models simulate ozone production?

This project evaluates and compares the representation of ozone production due to methane in a set of chemical transport models. It aims to judge the fitness of the models for the simulation of ozone production in Europe due to methane emissions originating within and outside Europe. On the basis of this evaluation, recommendations will be made for future research. In addition to a workshop at the German Environment Agency in November 2019, a final report on the project's findings is planned.