Global Pollution Maps Show Differences in Air Quality during COVID-19 Lockdown

A newly launched online platform developed by the European Space Agency enables the public user to detect pollutants around the world, including airborne coronavirus lockdowns and changes in air quality observed during shelter arrangements. The maps are pulling data from the European Space Agency’s (ESA) Copernicus Sentinel-5P satellite, which was launched in 2017 to map global pollutants with the help of a Tropomi instrument that can detect “unique fingerprints” of atmospheric gases accurately and at higher resolutions. Globally, interactive maps show a 14-day average nitrogen dioxide concentration, highlighting a “drastic reduction” in density across many regions.

Nitrogen dioxide (NO2) is a “bad smelling gas” emitted from vehicles and power plants when burning fuel. The U.S. Environmental Protection Agency says high concentrations of air can irritate the respiratory tract and cause asthma, coughing, shortness of breath, and breathing problems. When NO2 comes in contact with water, oxygen, and other chemicals, it can cause acid rain that is capable of damaging the fragile environment. Global concentrations can fluctuate greatly over days due to fluctuations in emission rates or changes in weather conditions, for which researchers can analyze the levels over a longer period of time.

Satellite images for March showed a steady drop in NO2 levels across China since the beginning of the year, partly because Stanford researchers say the 77,000 people could have been saved from the coronavirus outbreak due to the economic downturn.  Now, NO2 levels in the region are rising as pockets around the world begin to take shelter and lockdown measures.

Writes ESA, “Now the COVID-19 mitigation system is being relaxed in many countries and the NO2 concentration is also increasing. Across China, the relaxation of the Covid-19 step has brought the NO2 concentration back to normal, as shown in the figure below. “

Across Europe, a “strong decline” in NO2 concentrations was observed between Paris, Madrid, and Rome in several major cities between March and April this year.  Experts from the European Union’s Copernicus program have found that pollution levels in some cities have dropped by 50 percent compared to the credit for coronavirus -related lockdown measures. The ESA has decided to monitor air quality in Europe and around the world, especially in the context of changes in air quality.