ИСТИНА

Globally, effects of COVID-19 lockdown on pollution levels are evidenced. In Russia, the first social distancing and mandatory quarantines were introduced in April 2020. After first lockdown, waves of the COVID-19 pandemic have surged through communities; the world has experienced how to endure lockdowns and a shakeup of economics, employment force, and resources. Black carbon (BC) has become one of the most significant indicators of the pandemic environment impacts. Its emissions declined 11% during lockdowns over Europe, as compared to the same period in previous 5 years (Evangeliou et al., 2021). Changes were different in cities with major contributions from nontraffic related sources. How significant they occurred due to different economic and population activity is still uncertain. Moscow is the most densely populated northernmost megacity in Europe. Aerosool of megacity background is investigated at Aerosol Complex located in Metrological Observatory Moscow State University, during Covid-19 lockdown and recovery periods of 2020 (Popovicheva et al., 2021). Wave of COVID-19 followed the first one; the record for a number of cases per day, 9108, was broken on 18 June 2021 during the third pandemic wave , leaving a need to estimate the impact of various levels of restrictions