| Title: | Vertical distribution of volatile organic compounds conducted by tethered balloon in the Beijing-Tianjin-Hebei region of China |
| Author(s): | Geng C; Wang J; Yin B; Zhao R; Li P; Yang W; Xiao Z; Li S; Li K; Bai Z; |
| Address: | "State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Tianjin Eco-Environmental Monitoring Center, Tianjin 300191, China. State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address: yangwen@craes.org.cn" |
| DOI: | 10.1016/j.jes.2020.03.026 |
| ISSN/ISBN: | 1001-0742 (Print) 1001-0742 (Linking) |
| Abstract: | "Volatile organic compounds (VOCs) as precursors of ozone and secondary organic aerosols can cause adverse effects on the environment and human health. However, knowledge of the VOC vertical profile in the lower troposphere of major Chinese cities is poorly understood. In this study, tethered balloon flights were conducted over the juncture of Beijing-Tianjin-Hebei in China during the winter of 2016. Thirty-six vertical air samples were collected on selected heavy and light pollution days at altitudes of 50-1000 meters above ground level. On average, the concentration of total VOCs (TVOCs) at 50-100 m was 4.9 times higher than at 900-1000 m (46.9 ppbV vs. 8.0 ppbV). TVOC concentrations changed rapidly from altitudes of 50-100 to 401-500 m, with an average decrease of 72%. With further altitude increase, the TVOC concentration gradually decreased. The xylene/benzene ratios of 34/36 air samples were lower than 1.1, and the benzene/toluene ratios of 34/36 samples were higher than 0.4, indicating the occurrence of aged air mass during the sampling period. Alkenes contributed most in terms of both OH loss rate (39%-71%) and ozone formation potential (40%-72%), followed by aromatics (6%-38%). Finally, the main factors affecting the vertical distributions of VOCs were local source emission and negative dispersion conditions on polluted days. These data could advance our scientific understanding of VOC vertical distribution" |
| Keywords: | Air Pollutants/*analysis Beijing China Cities Environmental Monitoring Humans Ozone/*analysis Volatile Organic Compounds/*analysis OH loss rate (L(OH)) Ozone formation potential (OFP) Tethered balloon Vertical distribution Volatile organic compounds (VOCs; |
| Notes: | "MedlineGeng, Chunmei Wang, Jing Yin, Baohui Zhao, Ruojie Li, Peng Yang, Wen Xiao, Zhimei Li, Shijie Li, Kangwei Bai, Zhipeng eng Netherlands 2020/07/13 J Environ Sci (China). 2020 Sep; 95:121-129. doi: 10.1016/j.jes.2020.03.026. Epub 2020 May 4" |
