Climate change policies could increase smog

The EU has ambitious plans for reducing air pollution and climate change by 2050. Yet while the policy plans are separate, greenhouse gases and air pollutants come from the same sources, such as transportation and industry. Air quality and climate change are also linked at a far more basic level: chemistry. The air pollutant ground‑level ozone, for example, is of great concern because of its detrimental impact on human health and the environment. Ozone forms when certain compounds released by plants are oxidized in the presence of nitrogen oxides, a type of pollutant released through combustion.

Projections for air pollution in 2050 show that ozone levels should decrease as air pollution goes down. But the processes that form ozone work faster at higher temperatures, so as climate change leads to hotter summers, ozone damage could increase. Finally, climate policies to increase bioenergy production could further add to ozone damage through an increase in the compounds that can be converted to ozone.

In new research, conducted as part of the YSSP’15, Dutch PhD candidate Carlijn Hendriks explored these complex interactions. Using multiple models of economic markets, greenhouse gas emissions, land‑use change, and air chemistry transport, Hendriks found that the effect of a warming climate on ozone production was the key factor, far outweighing the reductions in ozone that would come from current EU air quality policy by 2050. The smallest effect came from bioenergy production, which would cause only a slight increase in ozone damage.

Text by Katherine Leitzell

Last edited: 21 August 2017