| Autor: |
Shuzheng Guo, Chunxiang Ye, Weili Lin, Yi Chen, Limin Zeng, Xuena Yu, Jinhui Cui, Chong Zhang, Jing Duan, Haobin Zhong, Rujin Huang, Xuguang Chi, Wei Nie, Aijun Ding |
| Zdroj: |
Atmospheric Chemistry & Physics Discussions; 2/19/2024, p1-18, 18p |
| Abstrakt: |
Oxygenated volatile organic compounds (OVOCs) are reactive species and the primary precursors of free radicals; thus, OVOCs play important roles in tropospheric chemistry. @Tibet field campaigns 2021 discovered surprisingly high levels and activity contributions of OVOCs at Lulang, a site with high vegetation cover and strong solar ultraviolet radiation on the southeast of the Tibetan Plateau (TP). The 13 OVOCs detected accounted for 49% of the total VOCs (TVOCs; average level of 11.7 ± 4.4 ppb), and the levels of these OVOCs exhibited typical diurnal variation, with high values in the daytime and a peak at approximately 12:00. OVOCs contributed 65% and 63% to VOC-kOH and the ozone formation potential, respectively, and thus had a strong influence on atmospheric chemical processes. Two independent methods were used to determine the contributions of various sources and revealed consistent conclusions regarding the importance of biological sources there. The source apportionment results obtained through positive matrix factorization indicated that sunlight-impacted and direct plant emission sources both related to plant sources contributed 47% of the TVOCs and 65% of the OVOCs. OVOC source fitting through the photochemical age parameterization method also indicated that biogenic sources made the largest contribution (67%) to OVOCs and revealed a clear peak at noon. In addition, biomass burning sources were found to be closely related to the VOC background because biomass burning is highly prevalent across the whole TP; these sources made the second greatest contribution (33%) to the TVOCs and contributed more than 23% of OVOCs. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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