According to a new study that has analyzed data from 46 countries (a total of 5,756 observation sites on the ground), which transmitted measurements of the atmospheric composition per hour in near real time, there has been a significant reduction in nitrogen dioxide emissions .
At the city level, 50 of the 61 cities analyzed show nitrogen dioxide reductions between 20 and 50%. Nitrogen dioxide (NO2) is an air pollutant that is produced mainly by the combustion of fossil fuels used by industry and transportation.
Pandemic restrictions
This significant reduction in pollution levels is due, according to the study authors, to the transport restrictions derived from COVID .
Normal variations in climate and atmospheric circulation change the composition and chemistry of the Earth’s atmosphere. Comparing 2020 nitrogen dioxide concentrations to 2019 or 2018 data alone would not reflect year-to-year differences .
But, because NASA’s model projections account for these natural variations, scientists can use them to analyze how much of the 2020 atmospheric composition change was caused by the COVID-19 containment measures .
The results are the result of computer models used by NASA researchers, which were presented at the 2020 International Conference on High Performance Computing, Networking, Storage and Analysis. Model simulation and machine learning analysis were carried out at NASA’s Climate Simulation Center.