Effect of ship emissions on O3 in the Yangtze River Delta region of China: Analysis of WRF-Chem modeling

Ruonan Wang; Xuexi Tie; Guohui Li; Shuyu Zhao; Xin Long; Lasse Johansson; Zhisheng An

doi:10.1016/j.scitotenv.2019.04.240

Effect of ship emissions on O₃ in the Yangtze River Delta region of China: Analysis of WRF-Chem modeling

Sci Total Environ. 2019 Sep 15:683:360-370. doi: 10.1016/j.scitotenv.2019.04.240. Epub 2019 May 11.

Authors

Ruonan Wang¹, Xuexi Tie², Guohui Li³, Shuyu Zhao³, Xin Long³, Lasse Johansson⁴, Zhisheng An³

Affiliations

¹ Key Lab of Aerosol Chemistry and Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; University of Chinese Academy of Science, Beijing 100049, China.
² Key Lab of Aerosol Chemistry and Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Center for Excellence in Urban Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Shanghai Key Laboratory of Meteorology and Health, Shanghai 200030, China; National Center for Atmospheric Research (NCAR), Boulder, CO 80303, USA. Electronic address: tiexx@ieecas.cn.
³ Key Lab of Aerosol Chemistry and Physics, SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
⁴ Finnish Meteorological Institute, Erik Palmenin aukio, 100101 Helsinki, Finland.

PMID: 31136963
DOI: 10.1016/j.scitotenv.2019.04.240

Abstract

The Yangtze River Delta (YRD) region locates on the eastern coast of China, and it has suffered severe O₃ pollutions due to high and mixed emissions of air pollutants. There are 3 different emission sectors for O₃ precursors in the region, including anthropogenic VOC_S and NO_X emissions, ship emissions (mainly NO_X), and biogenic emissions from a large forest (biogenic VOC_S). This unique emission mixture produces complicated chemical processes in studying the O₃ pollutions in the region. This study aims to identify the contribution of the ship emissions to O₃ pollutions, as well as the effect of mixing emissions on O₃ pollutions in YRD. To identify the individual emission effect, the WRF-Chem model is used in this study. The model generally performs well in simulating meteorological parameters and air pollutants against observations in YRD. Sensitive study suggests that the ship emissions have important effects on the O₃ concentrations over ocean and inland, with a maximum increase of 30-50 μg m^-3 occurred mainly in the ship track regions. However, the ship emissions have a very complicated effect on the in-land O₃ concentrations. In the north of Shanghai, the NO_X concentrations are high due to high anthropogenic emissions, and a further increase in NO_X emissions from ship results in depressing O₃ chemical production. In contrast, in the south of Shanghai, there are high biogenic VOC emissions (mainly isoprene) and low NOx concentrations. As a result, the O₃ concentrations are enhanced by 30-50 μg m^-3, due to the mixing between ship and forest emissions. This study suggests that ship emissions play important roles in controlling O₃ pollutions in YRD. Furthermore, the mixing emissions between ship, anthropogenic, and biogenic emissions in YRD produce a complicated O₃ chemical production and need to be carefully considered in controlling strategy of O₃ pollution in the region.

Keywords: O(3) pollutions; Ship emissions; The YRD region; WRF-Chem modeling.