Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8862645 | Atmospheric Pollution Research | 2018 | 10 Pages |
Abstract
To evaluate biogenic secondary organic aerosol (BSOA) tracers from biogenic precursors, fine particles (PM2.5) were collected using filter-based high-volume samplers from spring-summer of 2015 in the central part of Shanghai, China. The results showed that the isoprene SOA tracers exhibited the highest levels (17.64 ± 9.75 ng mâ3) and were always observed along with higher temperatures, which results in a higher tracer formation rate and isoprene emission strength. However, the isoprene SOA tracers showed a weak correlation with the relative humidity (p > 0.05). The isoprene SOA tracers showed remarkable correlations with the [H+] because of the enhanced formation of isoprene SOA in the acidic aerosols. On the basis of these results, 2-methylglyceric acid was determined to have weak correlations with other isoprene tracers, which indicated that it had different formation pathways from those of other isoprene SOA tracers. Cis-pinonic acid had negative correlations with other SOA tracers, indicating that it is the first product in the oxidation process. Furthermore, the isoprene-based tracers (SOCisoprene) were calculated to be 0.031-0.299 μg C mâ3 (with an average of 0.114 ± 0.062 μg C mâ3), which accounted for more than half of the biogenic SOA. The SOC estimation with SOA tracers (SOC tracer-based) averaged 0.155 ± 0.066 μg mâ3, with a range from 0.049 to 0.309 μg mâ3 during the sampling period, which amounted to 2.73% OC.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Atmospheric Science
Authors
Wenfei Zhu, Lina Luo, Zhen Cheng, Naiqiang Yan, Shengrong Lou, Yongpeng Ma,