The impact of ship emissions on PM2.5 and the deposition of nitrogen and sulfur in Yangtze River Delta, China

Dongsheng Chen; Xiaolei Tian; Jianlei Lang; Ying Zhou; Yue Li; Xiurui Guo; Wenlin Wang; Bo Liu

doi:10.1016/j.scitotenv.2018.08.313

The impact of ship emissions on PM_2.5 and the deposition of nitrogen and sulfur in Yangtze River Delta, China

Sci Total Environ. 2019 Feb 1:649:1609-1619. doi: 10.1016/j.scitotenv.2018.08.313. Epub 2018 Aug 25.

Authors

Dongsheng Chen¹, Xiaolei Tian², Jianlei Lang², Ying Zhou², Yue Li³, Xiurui Guo², Wenlin Wang⁴, Bo Liu⁵

Affiliations

¹ Key Laboratory of Beijing on Regional Air Pollution Control, Beijing University of Technology, Beijing 100124, China. Electronic address: dschen@bjut.edu.cn.
² Key Laboratory of Beijing on Regional Air Pollution Control, Beijing University of Technology, Beijing 100124, China.
³ Transport Planning and Research Institute, Ministry of Transport, Beijing 100028, China.
⁴ Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing, China. Electronic address: wwl@nies.org.
⁵ School of Geography Science, Nantong University, Nantong, China.

PMID: 30308929
DOI: 10.1016/j.scitotenv.2018.08.313

Abstract

Ship emissions contribute significantly to the deterioration of air quality, while their impacts on ambient PM_2.5 and depositions have not been comprehensively evaluated. This is especially true for China because it has a long coastline, busy shipping routes and many large ports. To fill this gap, this study applied the SMOKE/WRF/CMAQ modeling system to quantifying the impacts of ships on PM_2.5 compositions, annual and seasonal contribution to PM_2.5 as well as the wet and dry deposition of nitrogen and sulfur compounds over the land areas in YRD region for 2014. The results showed that 4.0% of annual PM_2.5 concentrations over the land areas could be explained by ship emissions and the largest contribution could reach up to 35.0% in port areas. Temporally, the contribution to PM_2.5 exhibited an obviously seasonal variation. The highest contribution was predicted in autumn (6.2%), followed by summer (5.4%), spring (3.6%) and winter (1.2%) for the land areas. Spatially, the contribution reached up to 13.6% along the coastline and dropped to 2.1% 300 km inland. As for the impacts on PM_2.5 components, the primary components were relatively small and increased mainly along the shipping routes and the Yangtze River, whereas the secondary components played a more important role in both water and land areas. The sulfur deposition due to ship emissions was occurred generally along the shipping routes and was dominated by the dry SO₂ deposition. The nitrogen depositions, on the contrary, was observed not only along the shipping routes but also extend to wide land areas. Further investigation revealed that ship emissions have caused an evident increase of dry nitrogen deposition in NO₂ and HNO₃, while a slight decrease in NH₃ over YRD region. These results indicated that comprehensive regulations of ship emissions are required considering their adverse effects on the ambient concentration of PM_2.5 and the deposition of sulfur and nitrogen.

Keywords: Depositions; PM(2.5); Ship emissions; WRF/CMAQ; Yangtze River Delta.