Unlikely effect of the coronavirus: Environment

Around January 2020, the Chinese authorities ordered citizens in Hubei Province to stay at home for the prevention of the spread of the coronavirus. With millions of people being put under quarantine, many businesses were closed and streets were cleared. However, it seemed like this sudden lockdown led to a surprising result—a blue sky.

Decrease of Nitrogen Dioxide in Major Cities of China
According to China’s Ministry of Ecology and Environment, the average days with good quality air had increased by 21.5% compared to the same time period in 2019. (CNN) Importantly, this did not only happen in Hubei Province.
NASA and the European Space Agency (ESA) pollution monitoring satellites had detected a dramatic reduction of nitrogen dioxide (NO2) over China between January and February. Nitrogen dioxide, a noxious gas emitted from power plants, motor vehicles, and industrial factories. Breathing air with a high concentration of nitrogen dioxide can irritate the human respiratory system causing diseases and infections. A high concentration of NO2 in the atmosphere can react with oxygen, water, and other chemicals to form acid rains.
The maps above show the density of NO2 across China from January 1-20, 2020 (before quarantine), and February 10-25, 2020 (during quarantine). The data above was collected by Tropospheric Monitoring Instrument (TROPOMI) on ESA’s Sentinel-5 satellite. The Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite is also taking similar data. (NASA).
Based on the map, the visible dark cloud filled with toxic gases over China’s major cities almost disappeared between January to February. The amount of nitrogen dioxide gases decreased dramatically in most of China— the orange color region representing the high concentration of NO2 had reduced significantly in merely one month. “This is the first time I have seen such a dramatic drop-off over such a wide area for a specific event,” said Fei Liu, an air quality researcher at NASA’s Goddard Space Center. According to NASA scientists, this decrease of nitrogen dioxide gas first appeared in Wuhan, and gradually spread across most of the country. (NASA)
The drop in nitrogen dioxide gas also coincided with the New Year celebrations in China. Based on the observation data, the air pollution level usually decreases around this period, then rises again after the celebration. Generally, businesses often close from the last week of January and early February to celebrate the festival.
The data below shows NO2 densities over three periods of 2020: January 1-20, 2020 (before New Year), January 28-February 9,2020 (during New Year), February 10-25, 2020 (after New Year). Comparing the values of nitrogen dioxide gases in 2020 with 2019, the density of nitrogen dioxide gases in 2020 was significantly lower than what is normally observed—the orange region with a high concentration of NO2 gases almost completely disappeared in 2020, leading to high air quality.

Decrease of Carbon Dioxide Gases in China
A similar pattern had also emerged with carbon dioxide (CO2)— a type of heat-trapping greenhouse gas, which is released through human activities such as burning fossil fuels (such as coal), deforestation, respiration processes, and volcanic eruptions. According to the Center for Research on Energy and Clean Air (CREA), an air pollution research center, CO2 emissions decreased by 25% due to measures to contain coronavirus from February 3-March 1. As the world’s biggest polluter, China produces 30% of carbon dioxide emissions in the world annually. Even in a short period, this significant drop can be huge. CREA estimates it is equivalent to approximately 200 million tons of carbon dioxide.

Reduction of Coal Consumption
According to CREA, China’s 70% reduction of domestic flights and the decrease in the production of steel and oil contributed to the decline of carbon dioxide emissions. However, many believed the fall of coal consumption in China is the biggest driver of this decline.
As the biggest producer and consumer of coal in the world, coal made up 59% of China’s energy use in 2018. This resource runs powerhouses and many heavy industries, it is also the main heat source for millions of people living in vast rural areas of China. According to CREA analysis of WIND data statistics, China’s major coal-fired power stations had a reduction of 36% of coal consumption from February 3 to March 1 compared to last year as the sudden coronavirus breakout put most of the country under quarantine or lockdown. Comparing China’s coal consumption in 2020 with previous years, the amount of coal consumption had decreased dramatically. Because of this significant drop, the amount of carbon dioxide emissions were able to decline.
“The largest consumers of coal — coal-fired power plants — have been affected a lot because electricity demand is down, I think it’s clear that this effect will continue for the next weeks and months because there has also been a major impact on the demand side of the economy,” said Myllyvirta.
In 2017, China’s President Xi Jin Ping had promised to make the major problem of pollution one of China’s “three battles”. In the following years, the Ministry of Ecology and Environment was created. The new policies were very effective. Based on the report released last year from Greenpeace and AirVisual, China’s overall pollution dropped 10% lower in major cities between 2017 and 2018. (CNN)
At this coronavirus pandemic, many Chinese activists believed this time might be the window to combat major environmental problems and implement these promised reforms.

“Revenge Pollution”
However, the concern is that once the coronavirus pandemic has passed, China will solely spend many efforts to restart its economy that was already hurt during the US-China trade war.
“There might be a round of economic stimulus which would inject cheap credits to heavy industries in China, and as a result of that we might see increasing pollutants and also carbon emissions in the second half of this year,” Li added.
The result of reopening heavy industries with more economic needs foreshadows the expense of the environment. This bounce-back-effect that can reverse any previous drop in toxic gas emissions is sometimes called by Li “Revenge Pollution”. (CNN)
President Xi Jin Ping had already made clear to factories and workers that they have to ramp up their activities as soon as the coronavirus threat passed to avoid steeper economic backlash.
“The reduction in air pollution has been very clear so if the pollution does come back, because of stimulus measures, because of heavy industry going into overdrive to make up for lost time, there could be a counter reaction,” said Myllyvirta. (CNN)
With the explosion of pollution known as the “airpocalypse” in recent years in China, this dramatic decrease of toxic gases in major cities seemed to be an encouraging lead. It is very interesting to consider the potential positive effects of the coronavirus pandemic on China’s environment, such as the decrease of nitrogen dioxide and carbon dioxide gases. However, it is still very unpredictable of the expenses on the environment when China restarts its economy in the future, whether the emissions will be reversed or not.
References
“Airborne Nitrogen Dioxide Plummets Over China.” NASA, NASA, 2020, earthobservatory.nasa.gov/images/146362/airborne-nitrogen-dioxide-plummets-over-china.

“Basic Information about NO2.” EPA, Environmental Protection Agency, 8 Sept. 2016, www.epa.gov/no2-pollution/ basic-information-about-no2#Effects.

“Carbon Dioxide Concentration.” NASA, NASA, 20 Feb. 2020, climate.nasa.gov/vital-signs/carbon-dioxide/.

“Hubei Timeline.” Johns Hopkins Coronavirus Resource Center, 2020,coronavirus.jhu.edu/data/hubei-timeline.

Wright, Rebecca. “There’s an Unlikely Beneficiary of Coronavirus: The Planet.” CNN, Cable News Network, 17 Mar. 2020,www.cnn.com/2020/03/16/asia/china-pollution-coronavirus-hnk-intl/index.html.