Evaluation of biogenic isoprene emissions and their contribution to ozone formation by ground-based measurements in Beijing, China

Ziwei Mo; Min Shao; Wenjie Wang; Ying Liu; Ming Wang; Sihua Lu

doi:10.1016/j.scitotenv.2018.01.336

Evaluation of biogenic isoprene emissions and their contribution to ozone formation by ground-based measurements in Beijing, China

Sci Total Environ. 2018 Jun 15:627:1485-1494. doi: 10.1016/j.scitotenv.2018.01.336. Epub 2018 Feb 9.

Authors

Ziwei Mo¹, Min Shao², Wenjie Wang³, Ying Liu⁴, Ming Wang⁵, Sihua Lu³

Affiliations

¹ Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
² Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China; State Joint Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China. Electronic address: mshao@pku.edu.cn.
³ State Joint Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
⁴ State Joint Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Beijing Innovation Center for Engineering Science and Advanced Technology (BIC-ESAT), Peking University, Beijing 100871, China.
⁵ Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science & Technology, Nanjing 210044, China.

PMID: 30857110
DOI: 10.1016/j.scitotenv.2018.01.336

Abstract

This study employs a mass balance technique-box model to calculate the biogenic isoprene emissions based on the ground-level measurements between October 2009 and September 2010 in Beijing. The annual magnitude, monthly variations and diurnal patterns of isoprene emissions are estimated. The annual emissions of isoprene were estimated to be 23.2Gg with an uncertainty of 120%. This falls within the range of previous emission inventories (EI; 3.8Gg to 36.3Gg between 1990 and 2010). Strong isoprene emissions were observed between May and September. The biggest difference was the isoprene emissions in May, with contributions of 23.3% to total annual emissions using box model estimates compared with 3.7% in EI. The diurnal profiles of isoprene emissions estimated in this study were generally similar to those in the EI, with the highest emissions occurring during mid-day (11:00-13:00). However, obvious differences were found for the growth rates and decreasing rates of isoprene emissions in the morning and afternoon respectively. Compared to anthropogenic volatile organic compounds (VOCs), the isoprene emissions contributed half (49.5%) of the total ozone formation potential (OFP) at 13:00 in August, which highlights the importance of isoprene in ozone formation. This study helps bound the isoprene emissions estimated by EI despite the inherent large uncertainty.

Keywords: Beijing; Box model; Emission inventory; Isoprene emission; Ozone formation potential.