Li Hui, Zheng Bo, Lei Yu, Hauglustaine Didier, Chen Cuihong, Lin Xin, Zhang Yi, Zhang Qiang, He Kebin
Shenzhen Key Laboratory of Ecological Remediation and Carbon Sequestration, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China.
Environ Sci Ecotechnol. 2024 Apr 27;21:100425. doi: 10.1016/j.ese.2024.100425. eCollection 2024 Sep.
Nitrogen oxides (NO), significant contributors to air pollution and climate change, form aerosols and ozone in the atmosphere. Accurate, timely, and transparent information on NO emissions is essential for decision-making to mitigate both haze and ozone pollution. However, a comprehensive understanding of the trends and drivers behind anthropogenic NO emissions from China-the world's largest emitter-has been lacking since 2020 due to delays in emissions reporting. Here we show a consistent decline in China's NO emissions from 2020 to 2022, despite increased fossil fuel consumption, utilizing satellite observations as constraints for NO emission estimates through atmospheric inversion. This reduction is corroborated by data from two independent spaceborne instruments: the TROPOspheric Monitoring Instrument (TROPOMI) and the Ozone Monitoring Instrument (OMI). Notably, a reduction in transport emissions, largely due to the COVID-19 lockdowns, slightly decreased China's NO emissions in 2020. In subsequent years, 2021 and 2022, reductions in NO emissions were driven by the industry and transport sectors, influenced by stringent air pollution controls. The satellite-based inversion system developed in this study represents a significant advancement in the real-time monitoring of regional air pollution emissions from space.
氮氧化物（NO）是空气污染和气候变化的重要成因，会在大气中形成气溶胶和臭氧。准确、及时且透明的NO排放信息对于减轻雾霾和臭氧污染的决策至关重要。然而，自2020年以来，由于排放报告延迟，对于全球最大排放国中国的人为NO排放背后的趋势和驱动因素缺乏全面了解。在此，我们表明，尽管化石燃料消耗增加，但利用卫星观测作为大气反演估算NO排放的约束条件，2020年至2022年中国的NO排放持续下降。这一下降得到了两种独立星载仪器数据的证实：对流层监测仪器（TROPOMI）和臭氧监测仪器（OMI）。值得注意的是，主要由于新冠疫情封锁措施，交通排放减少，使中国2020年的NO排放略有下降。在随后的2021年和2022年，NO排放的减少是由工业和交通部门推动的，这受到严格空气污染控制的影响。本研究中开发的基于卫星的反演系统代表了从太空对区域空气污染排放进行实时监测的重大进展。
