Warmer temperatures and higher atmospheric levels of methane could increase summertime ozone levels in the United States by 70 per cent in 2050, according to a new study. Ground-level ozone can trigger health problems such as asthma, bronchitis, and emphysema. Even short periods of unhealthy ozone levels can cause local death rates to rise. Ozone pollution also damages crops and other plants.
“It doesn’t matter where you are in the United States – climate change has the potential to make your air worse,” said Gabriele Pfister, lead author of the study. “A warming planet doesn’t just mean rising temperatures, it also means risking more summertime pollution and the health impacts that come with it.”
On the other hand, it was also found that sharp reductions in emissions of the ozone precursor pollutants, nitrogen oxides and volatile organic compounds, could reduce ozone levels even as the climate warms.
Two scenarios were examined. In one, emissions of nitrogen oxides and volatile organic compounds from human activities would continue at current levels through 2050. In the other, emissions would be cut by 60–70 per cent. Both scenarios assumed continued greenhouse gas emissions with significant warming.
Source: UCAR new release, 5 May 2014.
The study Projections of future summertime ozone over the U.S. is published online in the Journal of Geophysical Research-Atmospheres.