Affiliation:
1. School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China
2. Hubei Eco-Environmental Monitoring Centre, Wuhan 430079, China
3. Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Hong Kong 999077, China
Abstract
Wuhan experienced a noticeable enhancement in air quality from January to April 2020 due to the epidemic lockdown. The improvement was a combined result of anthropogenic emission reduction and meteorological variability. Environmental policymakers are often concerned about the impact of industrial production and human activities on improvements in environmental sustainability. This study split and quantified the impact of anthropogenic emissions on the pollution level changes of six major air pollutants (CO, SO2, NO2, O3, PM10, and PM2.5) for the first half year of 2019 to 2021 in Wuhan with an improved meteorological normalization algorithm. The results show sharp decreases in anthropogenic pollutant loads during 2020, except for O3, with the ranking of NO2 > PM10 > SO2 > CO > PM2.5. The decrease in NO2 emissions caused by humans was more than 50% compared to 2019. The low NO2 led to a decrease in O3 consumption, resulting in high O3 concentrations from February to April 2020 during the city lockdown. Moreover, except O3, the impact of anthropogenic and weather influences on air pollution exhibited opposing effects; that is, meteorology tended to aggravate pollution, while human intervention was conducive to improving air quality, and human factors played the dominant role. Of all six pollutants, O3 is the one that is relatively least subject to anthropogenic emissions. Although concentrations of SO2, NO2, PM10, and PM2.5 rebounded in 2021, none of them were able to return to their pre-lockdown levels, suggesting the epidemic’s continuous inhibition of people’s activities. Compared with 2019 and 2021, the atmospheric oxidation capacity and secondary aerosol formation showed an overall decreasing trend during 2020. This study provides a reference for assessing the effectiveness of anthropogenic emission reduction policies.
Funder
National Key R&D Program of China
Key Laboratory of National Geographical Census and Monitoring, Ministry of Natural Resources
Subject
Management, Monitoring, Policy and Law,Renewable Energy, Sustainability and the Environment,Geography, Planning and Development,Building and Construction
Reference45 articles.
1. Lv, Y. (2019). Tempo-Spatial Characteristics of Air Quality in Wuhan and the Influence of Meteorological Parameters, Huazhong Agricultural University. (In Chinese).
2. Addition of PM2.5 into the National Ambient Air Quality Standards of China and the Contribution to Air Pollution Control: The Case Study of Wuhan, China;You;Sci. World J.,2014
3. Importance of meteorology in air pollution events during the city lockdown for COVID-19 in Hubei Province, Central China;Shen;Sci. Total Environ.,2021
4. Real-time source apportionment of PM2.5 and potential geographic origins of each source during winter in Wuhan;Jiang;Environ. Sci.,2022
5. Using meteorological normalisation to detect interventions in air quality time series;Grange;Sci. Total Environ.,2019