Effects of a changing climate on summertime fine particulate matter levels in the eastern U.S. Issue 11 (10th June 2015)

• Record Type: Journal Article
• Authors: Day, Melissa C.; Pandis, Spyros N.
• Is Part Of: Journal of geophysical research. Volume 120:Issue 11(2015:Jun.)
• Page Start: 5706
• Page End: 5720
• Publication Date: 2015-06-10
• Subjects: Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1002/2014JD022889
• Languages: English
• ISSNs: 2169-897X

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>The chemical transport model PMCAMx is used to examine the effect of climate change on fine (under 2.5 µms) particulate matter (PM<sub>2.5</sub>) during the summer in the eastern United States. Meteorology from 10 years in the 1990s (present) and 10 years in the 2050s (future) based on the Intergovernmental Panel on Climate Change A2 scenario is used. Anthropogenic pollutant emissions are assumed to remain constant, while biogenic emissions are climate sensitive and, depending on species, increase between 15 and 27% on average. The predicted changes of PM<sub>2.5</sub> are modest (increases of less than 10% on average across the domain) and quite variable in space, ranging from +13% in the Plains to −7% in the Northeast. Variability is driven concurrently by changes in temperature, wind speed, rainfall, and relative humidity, with no single dominant meteorological factor. Sulfate and organic aerosol are responsible for most of the PM<sub>2.5</sub> change. The improved treatment of organic aerosol using the volatility basis set does not increase significantly its sensitivity to climate change compared to traditional treatments that neglect the volatility of primary particles and do not simulate the chemical aging processes. Future organic aerosol is predicted to be more oxidized due to increases of its secondary biogenic and anthropogenic components. These results suggest that the effects of planned and expected emission anthropogenic emission controls will be more important than those of climate change for PM<sub>2.5</sub> concentrations in 2050. Maximum daily 8 h average ozone increases by 5% on average are predicted, with a marked increase in the Northeast, Southeast, and Midwest.</p> </abstract>