The impacts of Covid-19 have been making headlines for months.  The negative impact on human health, economies and health systems has been devastating. But what we don’t hear a lot of is some positive news. Yes, there’s a silver lining in every situation! In the Covid-19 pandemic, that silver lining is cleaner air.

So, how exactly is Covid-19 linked to this ‘cleaner air’? Simply put – LOCKDOWN. Many countries across the world went into strict lockdown, this meant little to no travelling (read: less transport emissions), less economic activity and less people going to work (read: less chemicals released from factories). All of these drastic changes to our lifestyles positively affected the environment. It bettered the quality of air we breathe.  We know this because scientists have a way to measure air pollution, it’s called the ‘air quality index’. Over the months of lockdown this measurement has been monitored and it was found to be decreasing.

Interestingly, the air quality index was not the only way to see this positive change in our air quality but many people made observations of cleaner, blue skies becoming visible in their regions, in some cases for the first time in people’s lifetime. This positive change in our air quality can be attributed to the decrease of two gases in our atmosphere, namely, nitrogen dioxide and carbon dioxide. Here’s how:

Nitrogen dioxide

According to research, the levels of nitrogen dioxide in the air were much lower in 2020 between March 15 and April 30, than for the same period in 2019 as observed from satellite imagery data. Nitrogen dioxide is a highly reactive gas that is caused by the burning of fuel, mainly from cars, trucks and busses emissions. This gas has dire consequences for the environment in that when nitrogen dioxide interacts with water, oxygen and other chemicals in the atmosphere it forms acid rain. Acid rain is harmful to sensitive ecosystems such as lakes and forests.  Human health is also impacted on negatively as the quality of air is low.

Carbon dioxide

Carbon dioxide is a greenhouse gas that is emitted into the atmosphere in a number of ways. The two primary sources of carbon dioxide are natural (exhaling it as a waste product) and human activities (energy production, including burning coal, oil, or natural gas).  As a greenhouse gas, carbon dioxide contributes towards the earth’s greenhouse effect which is a process that traps the Sun’s heat to make earth a comfortable place.  The earth as a system requires balance and too much of anything destabilizes the system. This means that too much of CO₂ disrupts the balance and this has been the case with increased human activities.  China recorded a decrease in carbon dioxide levels, estimated at 18% between early February and mid-March. This was mainly attributed to the fall in the consumption of coal for industrial output (Madeleine Stone, 2020).

The biggest positive that came from a very negative situation in 2020 has been a better environment. We caught a virus but also cleaned up the environment.