Changing Ozone Depletion Potential

The changing Ozone Depleting Potential (ODP) of N₂O in a changing climate

Nitrous oxide (N₂O) is both a greenhouse gas and an ozone depleting substance with natural and anthropogenic sources. Its atmospheric concentration has increased significantly from pre-industrial times and is projected to continue to increase throughout the 21^st century. At present, N₂O is the dominant anthropogenic ozone-depleting substance emitted and given further increases in emissions projected for the future, it is important to understand how stratospheric chemistry will evolve to better understand how N₂O will affect the ozone layer.

Enlarged view: OzoneTrendPic3 — The Ozone Depletion Potential (ODP) of nitrous oxide (N₂O) in 2100 as a function of methane (CH₄) and carbon dioxide (CO₂) concentrations. The black squares show values corresponding to the appropriate CO₂ and CH₄ surface concentrations for the IPCC Representative Concentration Pathways (RCP) in 2100. It is clear that the ODP of N₂O varies considerably under different greenhouse gas scenarios. Figure from Revell et al. 2015.

A metric frequently used to compare how much ozone a particular species destroys is the ‘ozone depleting potential’ (ODP). Using the SOCOL chemistry-climate model, we have shown that the ODP of N₂O varies under different future greenhouse gas scenarios (external pageRevell et al., 2015). Using a single value to estimate the future ODP of N₂O is thus of limited use since a single value may not encompass the full range of possible ODP values.

Changing Ozone Depletion Potential

The changing Ozone Depleting Potential (ODP) of N2O in a changing climate

The changing Ozone Depleting Potential (ODP) of N₂O in a changing climate