The near empty motorway A3 is seen near Leverkusen, western Germany, on April 19 amid the pandemic. INA FASSBENDER/AFP via Getty Images
The world has learned much about the devastating impact of COVID-19 on human health and well-being. It is also waking up to the pandemic’s positive effects on the planet’s atmosphere, ecosystems, and biodiversity. Ever since it was first detected late in 2019, the disease outbreak and resulting lockdowns around the world have dramatically slowed globalization, especially the trade and travel that powered the largest economic boom in history. In the process, the pandemic has intensified many of the deep inequalities that define our world. Notwithstanding the incalculable pain and suffering generated by the coronavirus, there appears to be a silver lining. Specifically, government-led efforts to contain the spread of the disease have temporarily reduced air pollution and greenhouse gas emissions—especially carbon dioxide, nitrogen dioxide, and particulate matter. The question, however, is whether these improvements will be sustained after lockdowns ease.
Within a few months of the spread of COVID-19 across Asia, Europe, and North America, global carbon dioxide emissions fell by an astonishing 17 percent compared with average daily levels in 2019. A big reason for this was the sudden drop in manufacturing, power generation, shipping, and transportation. Satellites managed by NASA and Planet Lab detected steep declines in vehicular traffic, which also contributed to a sharp decline in the nitrogen dioxide hovering above the world’s sprawling metropolises. While these declines are promising, most climate scientists are not optimistic that these changes will persist in the long run. Their best estimate is that carbon dioxide declines may end up at around 4 to 7 percent by the end of 2020. But it is far too early to celebrate: Recent improvements will be wiped out if industrial activity and energy use roar back unchanged in 2021.
The COVID-19 pandemic disrupted virtually every industrial sector and supply chain—but few sectors were hit harder than the airline industry. The outbreak is considered to be the worst crisis to have ever hit the aviation sector. Travel restrictions between and within countries led to a reduction in the frequency of flights by almost 70 percent in May 2020 compared with the previous year, bankrupting a rash of airlines and putting most of the rest on life support from governments and central banks. The cost of air cargo tripled as shipping between countries ground to a halt. Not surprisingly, aviation’s carbon footprint shrank by 60 percent. (Incidentally, the sharp slowdown in aviation also reduced the accuracy of weather forecasts, in part because the number of daily measurements of air temperature, humidity, and wind speed received from airplanes by the U.S. National Oceanic and Atmospheric Administration declined from roughly 900,000 a day to only 300,000.)
Cleaner Air Over China
Swipe to compare levels of nitrogen dioxide pollution in January and February of this year
Source: NASA
The pandemic also contributed to a sharp reduction in car, truck, and bus traffic when cities around the world went into lockdown. In a matter of weeks, weekdays became weekends and rush hours evaporated. In Europe, cities such as Milan, Paris, Rome, Madrid, and London experienced declines in traffic of between 72 and 97 percent. In the United States, every metropolitan area experienced a reduction in traffic of at least 50 percent, with possibly the lowest amount of driving since the 1970s. Crowded Indian cities such as Bengaluru, Chennai, Delhi, Kolkata, and Mumbai saw traffic plummet, which helps explain why levels of nitrogen dioxide and particulates plunged by around 50 percent or more. And in China, nitrogen dioxide pollution fell by 48 percent after many of its cities went into lockdown. Wuhan experienced a 63 percent drop in nitrogen dioxide emissions in the months after the city of 11 million people was shuttered.
Cleaner Air Over Europe
Swipe to compare levels of nitrogen dioxide pollution in 2019 to this year
Source: European Space Agency
Clearer Skies Over India
Airborne particle concentration between March 31 and April 5, 2019, and during the same period in 2020
source: NASA
There is no guarantee that greenhouse-gas emissions will stay low after lockdowns are eased. In fact, evidence points to industrial pollution and air-travel emissions creeping back up in several countries. Car traffic is increasing in many cities after governments loosened restrictions. Since many city dwellers are understandably wary of public transit, the risk of a surge in commuting by car is real, especially in large metropolitan centers. Much depends on what national, state, and municipal governments do next. Some mayors, city councils, and planners are busily trying to modify their urban spaces to favor pedestrians and greener modes of transportation. They are finding considerable support from their residents: In a recent international survey, 3 in 4 people in the countries polled expect their governments to make environmental protection a priority when planning the post-pandemic recovery.
More positively, COVID-19 is intensifying support in some parts of the world for more investment in emissions reduction and “building back better” than before. Before COVID-19, climate action had already risen on the agenda, fueled in part by widespread protest movements such as Fridays for Future and Extinction Rebellion. And while national, state, and city governments are facing soaring deficits, there are many people who are reluctant to go back to the “old normal.” Some politicians recognize that COVID-19 has created a space to push forward plans for a greener economy. To wit, the European Union is advancing an $825 billion green stimulus plan to reach decarbonization targets more quickly. Enlightened city leaders also understand that greener cities are healthier cities. This helps explain the clamping down on cars and rapid spread of bicycle lanes, pedestrian streets, and ride-sharing initiatives in cities such as Athens, Barcelona, Berlin, Brussels, Minneapolis, New York, Paris, Rome, San Francisco, and Seattle. The United Nations even established a World Bicycle Day to spread awareness about how bikes can help power a greener post-pandemic future.
Satellite images show traffic on Paseo de la Castellana in downtown Madrid before the pandemic, soon after the lockdown began, and in July as traffic ticked up again. Satellite images ©2020 Maxar Technologies
But there are also risks that COVID-19 will delay action to address the world’s climate crisis. Among other things, it has slowed down international negotiations such as the U.N. Climate Change Conference, the annual pledging event to keep global temperature rises below 2 degrees Celsius, and diplomatic progress on agreements designed to protect biological diversity and the oceans. The pandemic is likewise distracting people from ongoing environmental calamities, including rampant forest fires and the industrial-scale deforestation of the Amazon. The economic distress generated by COVID-19 could also weaken national climate policies and investments as countries resort to fossil fuels, cut green subsidies, and abandon renewable energy plans. There’s also a risk of an increase in pollution, including increased microplastics entering waterways due to the production of disposable gloves, surgical masks, and other nonrecyclable products.
While they helped generate climate and environmental dividends, COVID-19 lockdowns are not the solution for comprehensively tackling climate change. Strict quarantining measures have slowed emissions. This in turn will reduce mortality and morbidity associated with outdoor air pollution, which causes more than 4.2 million deaths every year. But the crippling economic, social, and psychological effects of restrictive lockdowns are hugely damaging for people’s livelihoods, especially in poorer and more vulnerable communities. The fundamental point is that humans have unlimited needs, but the planet has limited capacity to satisfy them. The most important question in the short term is whether governments, businesses, and societies make the right decisions to ensure a downward trajectory of emissions over the next decade.
While it is a seductive idea, COVID-19 will not heal the earth. In the first half of 2020, photos of wild boars in Barcelona, Spain, goats taking over Welsh towns, clear views of the Himalayas from the state of Punjab in India, and aquamarine canals in Venice, Italy, were shared across the Internet. Hopeful memes suggested that COVID-19 was healing the planet, that nature’s tremendous capacity for regeneration had been activated, and that humans were the virus. And while it is true that air, noise, and water pollution as well as greenhouse gas emissions temporarily declined in the first half of the year, there is virtually no chance this will be sustained in the post-pandemic era if radical measures are not taken to decarbonize the global economy and alter consumption habits. The only way to truly heal the planet, and to save ourselves, is to take this opportunity to build radically greener economies, invest in renewable energy, phase out fossil fuels, and permanently shift to green mobility solutions.
