Since the coronavirus outbreak, many of us had to shelter-in-place or practice social distancing. For some of us, this meant working from home, and for others, it meant traveling to their workplace fewer days of the week. Either way, people commuting less to work can mean many different things: fewer cars on the streets, fewer factories, office and school buildings utilizing electricity. The scare of the spread of coronavirus has also gotten us re-thinking our travel decisions such as the local or international flights or long road trips that we once did without hesitation. Though all these sound like a massive disruption of plans, there is a silver lining to it: the positive impact the lockdown has on the environment.
Many researchers have been studying the impact of COVID–19 lockdown on the environment and it is definitely looking very good! In China, where strict lockdown procedures were implemented to curb COVID–19, there has been a significant reduction in the pollutant nitrogen dioxide (NO2). Satellite images released by NASA and the European Space Agency show striking differences in NO2 levels in China (below). One particular fact that intrigued me was that NO2 levels dropped by 40% in China, which is roughly equivalent to the removal of close to 200,000 cars from the roads.
The same is the case for countries in Europe and Asia. One such drastic reduction was seen in my home country, India, where the lockdown brought 1.3 billion people to a grinding halt. With businesses across the country closed and public and private transport suspended, the particulate matter in the air, dropped by a whopping 71% in just a week’s time. This image of the capital city Delhi is a witness to the difference. Why is this important you may ask? World Health Organization (WHO) estimates that more than 4 million people die every year from diseases caused by air pollution and that residents of many urban areas are constantly exposed to air quality that far exceeds the safe limits of WHO air quality standards.
The lockdown has not only positively affected the air quality, but it also has impacted water quality in several parts of the world. Venice, famous for its picturesque canals, has seen a large improvement in water quality since the boats and tourists have been restricted. While images of dolphins swimming in the Venetian canals are fake, the turbidity of canal waters in some high traffic areas decreased by up to 90%. The lower amounts of turbidity in the water allow greater penetration of sunlight to the water beds and thus benefit the creatures that live in it.
While the impact of COVID–19 lockdown on air and water quality may be more pronounced, there are some benefits that are lesser-known. According to WHO, noise pollution affects human health and contributes to several ailments including cardiovascular diseases. Lesser noise due to reduced ships and cruises is also beneficial to marine life.
Though the improvements in the environment due to the lockdown are encouraging, they are temporary. If we return to our “old normal”, a lot of these positive effects will diminish within short periods of time. As a scientist, I see the pandemic as a massive experiment that showed us what we could achieve due to restrictions on emissions. The lessons learned can be put to use in order to benefit the earth’s ecosystem in the long run. Some cities have already set a precedent in making permanent eco-friendly changes towards a greener future. Milan and Rome in Italy have taken steps to promote bikes and electric scooters to reduce the use of cars in the streets. In Seattle, almost 20 miles of streets will be permanently closed to most vehicle traffic by the end of May, giving a chance to bikers and pedestrians to freely and safely travel across the city. Social media giant Twitter has recently announced that the majority of their workforce will have the option to work from home permanently if they choose to. Other technology-based companies will likely follow suit. These positive changes will go a long way in cutting down emissions and help fight climate change.
- Zander S Venter, Kristin Aunan, Sourangsu Chowdhury, Jos Lelieveld. COVID-19 lockdowns cause global air pollution declines with implications for public health risk. medRxiv 2020.04.10.20060673; DOI: https://doi.org/10.1101/2020.04.10.20060673 (Pre-print article)
- Braga, F., Scarpa, G. M., Brando, V. E., Manfè, G., & Zaggia, L. (2020). COVID-19 lockdown measures reveal human impact on water transparency in the Venice Lagoon. The Science of the total environment, 736, 139612. Advance online publication. https://doi.org/10.1016/j.scitotenv.2020.139612