Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Atmos. Chem. Phys., 17, 12709-12724, 2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
26 Oct 2017
An updated emission inventory of vehicular VOCs and IVOCs in China
Huan Liu1,2, Hanyang Man1,2, Hongyang Cui3, Yanjun Wang4, Fanyuan Deng1, Yue Wang1, Xiaofan Yang1, Qian Xiao1, Qiang Zhang3, Yan Ding4, and Kebin He1,2 1State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, 100084, China
2State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing, 100084, China
3Ministry of Education Key Laboratory for Earth System Modeling, Center for Earth System Science, Tsinghua University, Beijing, 100084, China
4Vehicle Emission Control Center (VECC) of the Ministry of Environmental Protection, Beijing, 100084, China
Abstract. Currently, the emission inventory of vehicular volatile organic compounds (VOCs) is one of those with the largest errors and uncertainties due to suboptimal estimation methods and the lack of first-hand basic data. In this study, an updated speciated emission inventory of VOCs and an estimation of intermediate-volatility organic compounds (IVOCs) from vehicles in China at the provincial level for the year of 2015 are developed based on a set of state-of-the-art methods and an abundance of local measurement data. Activity data for light-duty vehicles are derived from trajectories of more than 70 000 cars for 1 year. The annual mileage of trucks are calculated from reported data by more than 2 million trucks in China. The emission profiles are updated using measurement data. Vehicular tailpipe emissions (VTEs) and four types of vehicular evaporation emissions (VEEs), including refueling, hot soak, diurnal and running loss, are taken into account. Results show that the total vehicular VOC emissions in China are 4.21 Tg (with a 95 % confidence interval range from 2.90 to 6.54 Tg) and the IVOC emissions are 200.37 Gg in 2015. VTEs are still the predominant contributor, while VEEs are responsible for 39.20 % of VOC emissions. The control of VEEs is yet to be optimized in China. Among VTEs, passenger vehicles emissions have the largest share (49.86 %), followed by trucks (28.15 %) and motorcycles (21.99 %). Among VEEs, running loss is the largest contributor (81.05 %). For both VTEs and VEEs, Guangdong, Shandong and Jiangsu province are three of the highest, with a respective contribution of 10.66, 8.85 and 6.54 % to the total amounts of VOCs from vehicles. 97 VOC species are analyzed in this VOC emission inventory. i-Pentane, toluene and formaldehyde are found to be the most abundant species in China's vehicular VOC emissions. The estimated IVOCs are another inconvenient truth, concluding that precursor emissions for secondary organic aerosol (SOA) from vehicles are much larger than previously estimated.

Citation: Liu, H., Man, H., Cui, H., Wang, Y., Deng, F., Wang, Y., Yang, X., Xiao, Q., Zhang, Q., Ding, Y., and He, K.: An updated emission inventory of vehicular VOCs and IVOCs in China, Atmos. Chem. Phys., 17, 12709-12724,, 2017.
Publications Copernicus
Short summary
The VOC emission inventory has large uncertainties. An updated VOC emission inventory of vehicles in China was developed based on a set of state-of-the-art methods and big data. Exhausts and evaporation were taken into account. Our results narrowed the gap between inventories and the real emissions. Detailed speciation reveals the chemical characteristics of emissions, which has the potential to improve the understanding of atmospheric chemical processes in polluted regions.
The VOC emission inventory has large uncertainties. An updated VOC emission inventory of...