“Wuhan”--- a name that stirred the hearts of millions of people around the world at the start of 2020.
Five months ago on January 23rd, the city entered a lockdown that completely isolated itself from the rest of the world; three months later, the city reopened and revived with the advent of spring. During this time, Wuhan gained much attention internationally as the initial location where the coronavirus was primarily discovered. However, the environmental impacts of the COVID-19 were often neglected as many only focused on the changes in numbers of confirmed cases or deaths. This post will discuss some notable environmental impact of COVID-19, specifically in the case of Wuhan, China.
The primary consequence of the shutdown in Wuhan was a significant improvement in the local air quality. Based on data from the NASA Earth Observatory and Wuhan Environmental Monitoring Department, the emissions of air pollutants including PM2.5 and various greenhouse gases decreased drastically after the lockdown order was imposed. Specifically, the atmospheric concentration of sulfur dioxide decreased by 22%, carbon dioxide decreased by 29%, and nitrogen oxides by a shocking 45%. The photo above graphically compares the level of tropospheric nitrogen dioxide in Wuhan during Chinese New Year in 2019 and 2020. The stark contrast between the high levels of NO2 in 2019 and the extremely low levels in 2020 exemplifies the dramatic impact of the epidemic on the environment. Other toxic air pollutants such as PM2.5 also decreased by 38%, which largely reduced the risks of adverse health effects that often result from air pollution.
The enormous reduction of air pollutants was a direct consequence of restricted transportation and business/factory shutdowns. Due to the lockdown, city residents were ordered to stay at home and prohibited to travel except emergency cases. Few cars or people could be seen outside on the road, as the picture depicts above. The dramatic decrease of public and private transportation directly reduced the emissions of greenhouse gases such as carbon dioxide to the atmosphere. The shutdown of stores and factories also to a great extent contributed to the improved air quality because emissions of nitrogen oxides and sulfur oxides were significantly reduced due to disrupted industrial processes. As a result, the pandemic has brought temporary benefits to the environment as anthropogenic activities were hampered by the lockdown.
Although the air quality improved, the epidemic imposed great concerns on the quality of nearby surface water and underground water sources. Due to the immense increase in hazardous waste disposal from medical facilities, risks of secondary pollution from sewage and wastewater increased substantially as well. Ineffectively treated wastewaters could contain viruses that may lead to more harm to public health. Therefore, to prevent further detrimental impacts of the virus on both the environment and public safety, the government implemented stricter monitoring of water sources near sewage or waste disposal sites and more extensive control over waste collection and treatment. Above is a photo of an environmental department staff conducting water quality tests in a lake near the Wuhan area.
The spread of the virus is already under control in the city of Wuhan. However, many other places in the world are still suffering from this extremely contagious disease. Hopefully, as more and more countries incorporate effective policies to contain the virus and maintain public health, greater concerns toward the environmental impact of COVID-19 would be addressed in the future.