Articles | Volume 16, issue 5
Research article
08 Mar 2016
Research article |  | 08 Mar 2016

Source apportionment and dynamic changes of carbonaceous aerosols during the haze bloom-decay process in China based on radiocarbon and organic molecular tracers

Junwen Liu, Jun Li, Di Liu, Ping Ding, Chengde Shen, Yangzhi Mo, Xinming Wang, Chunling Luo, Zhineng Cheng, Sönke Szidat, Yanlin Zhang, Yingjun Chen, and Gan Zhang

Abstract. Fine carbonaceous aerosols (CAs) is the key factor influencing the currently filthy air in megacities in China, yet few studies simultaneously focus on the origins of different CAs species using specific and powerful source tracers. Here, we present a detailed source apportionment for various CAs fractions, including organic carbon (OC), water-soluble OC (WSOC), water-insoluble OC (WIOC), elemental carbon (EC) and secondary OC (SOC) in the largest cities of North (Beijing, BJ) and South China (Guangzhou, GZ), using the measurements of radiocarbon and anhydrosugars. Results show that non-fossil fuel sources such as biomass burning and biogenic emission make a significant contribution to the total CAs in Chinese megacities: 56 ± 4 in BJ and 46 ± 5 % in GZ, respectively. The relative contributions of primary fossil carbon from coal and liquid petroleum combustions, primary non-fossil carbon and secondary organic carbon (SOC) to total carbon are 19, 28 and 54 % in BJ, and 40, 15 and 46 % in GZ, respectively. Non-fossil fuel sources account for 52 in BJ and 71 % in GZ of SOC, respectively. These results suggest that biomass burning has a greater influence on regional particulate air pollution in North China than in South China. We observed an unabridged haze bloom-decay process in South China, which illustrates that both primary and secondary matter from fossil sources played a key role in the blooming phase of the pollution episode, while haze phase is predominantly driven by fossil-derived secondary organic matter and nitrate.

Short summary
Many Chinese cities now are suffering the high loadings of fine particular matters, which can bring a lot of negative impacts on air quality, human health, and the climate system. The Chinese government generally focuses on the control of the emissions from vehicles and industry. Our results evidently show that the burning of biomass materials such as wood and agricultural residues can lead to the urban air pollution in China. The characteristic of haze covering China is distinct from regions.
Final-revised paper