COVID-19 lockdown in Europe leads to cleaner air and reduced ozone
The COVID-19 lockdown in Europe led to a decrease in air pollution, especially NO and NO2 emissions. This reduction affected the levels of tropospheric ozone (O3) in the atmosphere. Research using aircraft campaigns and simulations showed that the lockdown caused a 55% drop in NO and NO2 in the upper troposphere, slowing down O3 production. The lockdown also shifted the chemical regime in the upper troposphere to be limited by NOx instead of VOCs.
