Pollution and greenhouse gas emissions have fallen across continents as countries take extreme measures to stop the spread of the new coronavirus. Is this just a temporary change, or could it lead to longer-lasting falls in emissions?
In just a few months, the world has been transformed. With thousands of people dying, and hundreds of thousands becoming infected from a coronavirus that was previously unknown before appearing in the city of Wuhan in December 2019. Additionally, even for the millions of people who haven’t caught the disease, their entire way of life was changed by this virus.
The streets of Wuhan, China, are empty and abandoned after authorities implemented a strict lockdown. In Italy, the most extensive travel restrictions were made since World War Two. In London, the normally bustling pubs, bars, and theatres are now closed and people were instructed to stay in their homes. Worldwide, flights are being canceled or turning around in mid-air, as the aviation industry struggles. Most people are now stuck in their homes, practicing social distancing and working remotely.
Every country aims to control the spread of the virus, and hopefully, to reduce the death toll. However, this virus has led to some unexpected consequences. As industries, transport networks and businesses were forced to close down, it has brought a sudden drop in carbon emissions. Compared with this time last year, levels of pollution in New York have reduced by nearly 50% because of measures taken to stop the spread of the virus.
For instance, in China, the carbon emissions fell by 25% at the start of the year as people were forced to stay at home to stop the spread of the virus, factories shuttered and coal use fell by 40% at China’s six largest power plants since the last quarter of 2019. The proportion of days with “good quality air” was up 11.4% compared to last year in 337 cities across China, according to its Ministry of Ecology and Environment. The same goes for Europe, where satellite images have shown nitrogen dioxide (NO2) emissions fading away over northern Italy. A similar story is playing out in Spain and the UK.
Only an extreme threat like COVID-19 could have generated such a profound change so fast. At the time of writing, global deaths from the virus had passed 53,000, with more than 1,000,000 cases confirmed worldwide. As well as the toll of deaths, the pandemic has brought widespread job losses and threatened the livelihoods of millions as businesses struggle to survive considering the strict restrictions that have been put in place because of the coronavirus. Economic activity has stopped and stock markets have tumbled alongside the falling carbon emissions. It’s the precise opposite of the drive towards a decarbonized, sustainable economy that many have been wanting for decades.
A global pandemic that is taking people’s lives certainly shouldn’t be seen as a way of bringing about environmental change either. Therefore, it’s far from certain how lasting this dip in emissions will be. When the pandemic will eventually be over, no one knows what will happen with the carbon and pollutant emissions, because it can “bounce back” so much that it will be as if this clear-skied interlude never happened? Or could the changes we see today have a more persistent effect?
The first thing to consider, says Kimberly Nicholas, a sustainability science researcher at Lund University in Sweden, is the different reasons that have caused the emissions to drop. Take transport, for example, which makes up 23% of global carbon emissions. These emissions have fallen in a very short period of time in the countries where public health measures were taken, like quarantine and keeping people in their homes, which lead to cutting down unnecessary travel. Additionally, driving and aviation are key contributors to emissions from transport, contributing 72% and 11% of the transport sector’s greenhouse gas emissions respectively.
It is a fact that for the duration of reduced travel during the pandemic, these emissions will stay lowered, but what will happen when measures are eventually lifted?
In terms of routine trips like commuting, those miles left untravelled during the pandemic aren’t going to come back, because no one is going to travel to the office twice a day to make up for all the times that we had to work from home, says Nicholas. But what about other kinds of travel, might the self-isolation and quarantine encourage people to travel more when the option is there again?
“I can see arguments in both directions,” says Nicholas. “It may be the case that people who are avoiding travel right now are really appreciating spending time with families and focusing on those really core priorities. These moments of crisis can highlight how important those priorities are and help people focus on the health and wellbeing of family, friends and community.”
If this change in focus as a result of the pandemic is going to stick, then this could help to keep emissions lower, Nicholas suggests.
But there’s another way it could go. “It could also be that people are putting off long-distance trips but plan on taking them later,” Nicholas says. Frequent flying causes a large part of the carbon footprint for people who do it regularly, so these emissions could simply come back if people return to their old habits. (Read more about how to go on a “flight diet”.)
This is not the first time that an epidemic has left its mark on atmospheric carbon dioxide levels. Throughout history, the spread of the disease has been connected to lower emissions, even well before the industrial age.
Julia Pongratz, professor for physical geography and land-use systems at the Department of Geography at the University of Munich, Germany, found that epidemics such as the Black Death in Europe in the 14th Century, and the epidemics of diseases like smallpox brought to South America with the arrival of the Spanish conquistadors in the 16th Century, both left their marks on atmospheric CO2 levels, as Pongratz found by measuring tiny bubbles trapped in ancient ice cores.
Those changes were the result of the high death rates from disease and, in the case of the conquest of the Americas, from genocide. Other studies have found that these deaths caused many large tracts of previously cultivated land to become abandoned, growing wild and sinking large quantities of CO2.
The impact from the coronavirus pandemic is not predicted to lead to anywhere near the same number of deaths, so it is unlikely to generate widespread change in land use. Its environmental impacts are more similar to those of recent world events, such as the financial crash of 2008 and 2009. “Then, global emissions dropped immensely for a year,” says Pongratz.
The reduction in emissions in 2008 was mainly due to reduced industrial activity, which contributes to carbon emissions on a comparable scale to transport. Combined emissions from industrial processes, manufacturing, and construction make up 18.4% of global anthropogenic emissions. The financial crash of 2008-2009 generated an overall dip in emissions of 1.3%. But this quickly rebounded by 2010 as the economy recovered, leading to an all-time high.
“There are hints that coronavirus will act the same way,” says Pongratz. “For example, the demand for oil products, steel, and other metals has fallen more than other outputs. But there are record-high stockpiles, so production will quickly pick up.”
One factor that could influence whether or not these emissions bounce back is how long the coronavirus pandemic lasts. “At the moment that’s hard to predict,” says Pongratz. “But it could be that we see longer-term and more substantial effects. If the coronavirus outbreak continues to the end of the year then consumer demand could remain low because of lost wages. Output and fossil fuel use might not recover that quickly, even though the capacity to do so is there.”
2020 began with a drop in global emissions by 0.3%, which is less pronounced than the crash of 2008-2009.
However, the OECD predicts that the global economy will still grow back in 2020, even though growth predictions have fallen by half because of COVID-19. But even with this comeback, researchers such as Glen Peters of the Center for International Climate and Environment Research in Oslo believe that 2020 may still present a drop in global emissions of 0.3%, less pronounced than the crash of 2008-2009, but also with an opportunity for less rebound if efforts to stimulate the economy are focused towards sectors such as clean energy.
Force of habit
In addition, there are other, less direct ways in which the new coronavirus could have a longer-term impact on sustainability, too. The first one is pushing the climate crisis off people’s minds, as the more pressing concern of saving lives become more important.
Secondly, it is quite simply making discussion regarding the climate more difficult as mass events are now postponed. Greta Thunberg has urged for digital activism to take the place of physical protests due to the coronavirus outbreak, while the biggest climate event of the year, COP26, is currently scheduled to take place in November. COP26 is expected to attract 30,000 delegates from around the world. The conference organizers are still working towards hosting the event in Glasgow, a COP26 spokesperson says, although they are in frequent contact with the UN and the current COP president in Chile, among other partners.
Moreover, there may be another way that the behavioral changes taking place around the world could carry over beyond the current coronavirus pandemic.
“We know from social science research that interventions are more effective if they take place during moments of change,” says Nicholas.
A 2018 study led by Corinne Moser at Zurich University of Applied Sciences in Switzerland found that when people weren’t allowed to drive and were given free e-bike access instead, they drove much less when they eventually got their car back. While a study in 2001 led by Satoshi Fujii at Kyoto University in Japan found that when a motorway closed, forcing drivers to use public transit, the exact same thing happened because when the road reopened, people who had formerly been committed drivers traveled by public transport more frequently.
Additionally, times of change can create lasting habits. During the coronavirus pandemic, those habits that are by any chance good for the climate might be traveling less or, perhaps, cutting down on food waste as we experience shortages due to stockpiling.
One response to the coronavirus outbreak that has generated mixed reactions from climate scientists is the ways that many communities have taken big steps to protect each other from the health crisis. The speed and extent of the response has given some hope that rapid action could also be taken on climate change if the threat it poses was treated as urgently.
“It… shows that at the national, or international level, if we need to take action we can,” Donna Green, associate professor at University of New South Wales’s Climate Change Research Centre in New Zealand, told CNN. “So why haven’t we for the climate? And not with words, with real actions.”
But for others, such as Nicholas, the community action has sparked hope for the climate in the longer term. And Pongratz sees the time afforded by self-isolation as a good opportunity for people to take stock of their consumption.
It’s safe to say that no one would have wanted the drop in emissions to happen this way. COVID-19 has taken the lives of more than 53,000 people, health services, jobs, and mental health. But, if anything, it has also shown the difference that communities can make when they look out for each other, and that there are definitely good lessons that could be invaluable in dealing with climate change.