This study investigated variations in nitrogen dioxide(NO_(2))levels in Ukraine during two significant periods:the COVID-19 pandemic lockdown in 2020 and the armed conflict with Russia in 2022.Original and reprocessed...This study investigated variations in nitrogen dioxide(NO_(2))levels in Ukraine during two significant periods:the COVID-19 pandemic lockdown in 2020 and the armed conflict with Russia in 2022.Original and reprocessed Sentinel 5P data products were utilized for the analysis.A machine learning model was employed to generate a business-as-usual NO_(2)time series that accounted for meteorological variability.For the nine most populous cities in Ukraine,during the lockdown in 2020 we observed a moderation of increases in NO_(2)levels during the lockdown compared to the pre-lockdown levels.Looking at the same months during the conflict period in 2022,we identified much more significant reductions in NO_(2)level in these cities,averaging 12.1%for original and 18.1%for reprocessed datasets.Besides our examination of major urban areas,we observed reductions in NO_(2)levels in areas surrounding coal power plants damaged or destroyed by the conflict.For the major urban areas in Ukraine,we conclude that changes in daily anthropogenic activities due to the conflict-related events had more substantial impacts on NO_(2)levels than did COVID-19 lockdown.展开更多
基金supported by the Ministry of Education,Culture,Sports,Science and Technology-Japan,and the International Digital Earth Applied Science Research Center at Chubu University.
文摘This study investigated variations in nitrogen dioxide(NO_(2))levels in Ukraine during two significant periods:the COVID-19 pandemic lockdown in 2020 and the armed conflict with Russia in 2022.Original and reprocessed Sentinel 5P data products were utilized for the analysis.A machine learning model was employed to generate a business-as-usual NO_(2)time series that accounted for meteorological variability.For the nine most populous cities in Ukraine,during the lockdown in 2020 we observed a moderation of increases in NO_(2)levels during the lockdown compared to the pre-lockdown levels.Looking at the same months during the conflict period in 2022,we identified much more significant reductions in NO_(2)level in these cities,averaging 12.1%for original and 18.1%for reprocessed datasets.Besides our examination of major urban areas,we observed reductions in NO_(2)levels in areas surrounding coal power plants damaged or destroyed by the conflict.For the major urban areas in Ukraine,we conclude that changes in daily anthropogenic activities due to the conflict-related events had more substantial impacts on NO_(2)levels than did COVID-19 lockdown.
