| Title: | Responses of Photochemical Air Pollution in California's San Joaquin Valley to Spatially and Temporally Resolved Changes in Precursor Emissions |
| Author(s): | Wang Y; Bastien L; Jin L; Harley RA; |
| Address: | "Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States. Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "Ground-level ozone adversely affects human health and ecosystems. The effectiveness of control programs depends on which precursor(s) are controlled, by how much, and where and when emission reductions occur. We use the adjoint of the Community Multiscale Air Quality model to investigate odd oxygen (O(x) identical with O(3) + NO(2)) sensitivities in California's San Joaquin Valley (SJV) to precursor emissions from local and upwind sources. Sensitivities are mapped and disaggregated by hour and day. Taken together, impacts of precursor emissions in the San Francisco Bay area and Sacramento Valley are similar in magnitude to impacts of local SJV emissions. Same-day emission sensitivities are mostly attributable to local sources, with the most influential anthropogenic emissions of VOCs (volatile organic compounds) and NO(x) (nitrogen oxides) occurring in the morning (9-11 am) and early afternoon hours (1-3 pm), respectively. For the northernmost SJV receptor, the influence from Sacramento Valley emissions peaks 5-6 h later than Bay area emissions; this difference diminishes for SJV receptors located further downwind. Results show a shift toward more NO(x)-sensitive conditions in the afternoon with all but the southernmost receptor shifting from VOC- to NO(x)-sensitive conditions. We also evaluate opportunities to control pollution through shifts in precursor emission location and timing" |
| Keywords: | *Air Pollutants/analysis *Air Pollution Ecosystem Environmental Monitoring/methods Humans *Ozone/chemistry San Francisco *Volatile Organic Compounds Ozone adjoint method air pollution oxides of nitrogen volatile organic compounds; |
| Notes: | "MedlineWang, Yuhan Bastien, Lucas Jin, Ling Harley, Robert A eng Research Support, Non-U.S. Gov't 2022/04/26 Environ Sci Technol. 2022 Jun 7; 56(11):7074-7082. doi: 10.1021/acs.est.1c07011. Epub 2022 Apr 25" |
