Feng Xu, Ma Yaping, Lin Haipeng, Fu Tzung-May, Zhang Yan, Wang Xiaolin, Zhang Aoxing, Yuan Yupeng, Han Zimin, Mao Jingbo, Wang Dakang, Zhu Lei, Wu Yujie, Li Ying, Yang Xin
John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States.
National Meteorological Information Center, China Meteorological Administration, Beijing 100081, China.
Environ Sci Technol. 2023 Nov 7;57(44):16999-17010. doi: 10.1021/acs.est.3c04155. Epub 2023 Oct 19.
In early 2020, two unique events perturbed ship emissions of pollutants around Southern China, proffering insights into the impacts of ship emissions on regional air quality: the decline of ship activities due to COVID-19 and the global enforcement of low-sulfur (<0.5%) fuel oil for ships. In January and February 2020, estimated ship emissions of NO, SO, and primary PM over Southern China dropped by 19, 71, and 58%, respectively, relative to the same period in 2019. The decline of ship NO emissions was mostly over the coastal waters and inland waterways of Southern China due to reduced ship activities. The decline of ship SO and primary PM emissions was most pronounced outside the Chinese Domestic Emission Control Area due to the switch to low-sulfur fuel oil there. Ship emission reductions in early 2020 drove 16 to 18% decreases in surface NO levels but 3.8 to 4.9% increases in surface ozone over Southern China. We estimated that ship emissions contributed 40% of surface NO concentrations over Guangdong in winter. Our results indicated that future abatements of ship emissions should be implemented synergistically with reductions of land-borne anthropogenic emissions of nonmethane volatile organic compounds to effectively alleviate regional ozone pollution.
2020年初，两件独特的事件扰乱了中国南方周边船舶污染物的排放，为船舶排放对区域空气质量的影响提供了见解：由于新冠疫情导致船舶活动减少，以及全球对船舶实施低硫（<0.5%）燃油规定。2020年1月和2月，相对于2019年同期，中国南方船舶氮氧化物、硫氧化物和一次颗粒物的估计排放量分别下降了19%、71%和58%。船舶氮氧化物排放量的下降主要发生在中国南方的沿海水域和内陆水道，原因是船舶活动减少。船舶硫氧化物和一次颗粒物排放量的下降在中国国内排放控制区以外最为明显，原因是那里改用了低硫燃油。2020年初船舶排放的减少导致中国南方地表氮氧化物水平下降了16%至18%，但地表臭氧水平上升了3.8%至4.9%。我们估计，冬季船舶排放占广东地表氮氧化物浓度的40%。我们的结果表明，未来船舶排放的减排应与陆地人为源非甲烷挥发性有机化合物排放的减少协同实施，以有效缓解区域臭氧污染。
