AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Health and Air Quality Benefits of Reduced Primary Ultrafine Particulate Matter Associated with the No-Burn Day Rule in the San Joaquin Valley, California
Jianlin Hu, MICHAEL KLEEMAN, David Lighthall, University of California, Davis
Abstract Number: 439 Working Group: Urban Aerosols
Abstract The San Joaquin Valley (SJV) in California has the most severe PM2.5 pollution in the US during the winter season due to its unique topography and strong stagnant meteorology that traps the emissions inside the shallow surface layer. Previous studies have identified that residential wood combustion contributed a large fraction of PM2.5 in the SJV. Starting from 2003 November, the no-burn day rule has been implemented to mitigate wintertime PM2.5 pollution in the SJV. Studies showed that this rule has improved the air quality in the SJV by reducing PM2.5.
Residential wood combustion also emits large amount of ultrafine particles (UFP). Toxicology studies indicate that UFP may be more harmful to public health than PM2.5. The purpose of this study is to investigate the benefits of the no-burn day rule on the primary UFP ambient concentrations and consequently on the public health in the SJV during 2006-2010. The source oriented UCD_P model was used to predict the UFP concentrations with a horizontal grid resolution of 4 km. The predicted UFP concentrations are in good agreement with measured concentrations. The predicted UFP source contributions were also compared to source apportionment results estimated from the receptor-oriented Chemical Mass Balance (CMB) model. The relative source contributions predicted by the two methods are in general agreement in most of the episodes considering the uncertainties in measurements, even though the UCD_P model predicts higher wood combustion UFP concentration. UCD_P calculations suggest that the average UFP concentration was reduced by 43% on the no-burn days in the SJV. County-specific population weighted concentrations of UFP are calculated and used to estimate the health benefit of the no-burn rule in the SJV based on established exposure-health relationships.