The streets are empty, the skies are quiet and in many places, the air is cleaner than it has been in years. Lockdown measures due to COVID-19 around the globe have so far had a major impact on air pollution.
In the United States, NASA recorded a 30% decrease in air pollution over the northeast coast for March 2020, in comparison to March averages from 2015 to 2019.
Image of the US between 2015 and 2019; image on the right shows pollution levels in March 2020. (GSFC/NASA)
n Europe, even more dramatic changes have been reported. Using the European Space Agency’s Copernicus network of satellites, scientists from the Royal Netherlands Meteorological Institute (KNMI) found that nitrogen dioxide concentrations dropped by 45% in Madrid, Milan and Rome, when compared with March-April averages of last year. Paris meanwhile saw a drop of 54% in pollution levels over the same period.
While the coronavirus has undoubtedly had a positive immediate effect on air quality, some believe that it is in fact the study of climate change that will reap the greatest benefits from the pandemic in the long run.
According to Prof. Ori Adam, an expert on climate research at the Hebrew University of Jerusalem’s Institute of Earth Science, lockdowns across the world will help scientists reveal the true extent of humanity’s impact on the planet.
“This is a very unique opportunity to answer one of the most urgent questions which is: What is our role in climate change?” Adam told The Media Line. “We might get some important answers from that and if we do, it could be a serious catalyst for policy change.”
Adam called the widespread impact of COVID-19 on human mobility and industrial production a “unique experiment that we haven’t been able to do over the past few decades.” Researchers will be able to accurately measure the link between human-made aerosols and CO2 emissions on global warming and climate change over the next few months.
“On the one hand, we pollute by putting greenhouse gases in the atmosphere, but we also pollute the atmosphere with these tiny particles [aerosols] and they actually have a balancing effect,” he explained. “Some people are assuming that because of this reduction in pollution, we will halt climate change but it’s not that obvious that this will be the case. …We can’t really say whether this [pandemic] will have a cooling or a warming effect on the climate.”
Aerosols are dust and particles caused by fossil fuels and other human activities. They are believed to reduce the amount of solar radiation reaching the surface of the Earth, thereby creating a cooling effect. Known as global dimming, the phenomenon is an active area of research for climate scientists.
“We don’t know what the net effect of aerosols is,” Adam affirmed. “Once we understand that we will be able to reduce the uncertainty in climate change predictions significantly.”
In climate science, he said, there is a tug-of-war between many different competing mechanisms – which all have an effect on climate change as a whole. But because many big questions remain unanswered, researchers’ ability to impact policymakers and politicians has been negatively affected.
“It’s clear that humans play a major role [in climate change],” Adam said. “The problem is that we can’t put a number on it and the error bar is really large. There are other influences, for example, natural variability, [which is] the mean global temperature that will change even if we don’t emit anything into the atmosphere.”
Still, Adam believes that while scientists do not yet possess enough data to assess the exact role that humans play in climate change, COVID-19 could change all that.
“Maybe the coronavirus will give us a unique [opportunity] to help us constrain our understanding of how we affect climate,” he said, adding that he also believes the pandemic will encourage many countries to turn away from oil and move more quickly to cleaner sources of energy like wind and solar power.
In fact, it seems that man-made pollution is responsible for at least some coronavirus-linked deaths.
A Harvard study released earlier this month demonstrated that people infected with COVID-19 are more likely to die of the virus if they live in areas with higher air pollution. Conducted by the Harvard T.H. Chan School of Public Health, researchers analyzed data from 3,080 counties throughout the US and compared levels of PM2.5 (or particulate matter produced by the burning of fossil fuels) with the number of coronavirus deaths in each place.
The study found that those who had had greater exposure to PM2.5 over a longer period were at a 15% greater risk of dying from the novel virus over those living in areas with less of this kind of pollution.
“We found that people living in counties in the United States that have experienced higher levels of air pollution over the past 15-20 years have a substantially higher COVID-19 mortality rate, after accounting for differences in population density,” Dr. Francesca Dominici, a senior author of the study, told The Media Line in an email. “This increase accounts for adjustment for county-level characteristics.”
Dominici said that once the economy restarts air pollution levels will quickly return to pre-pandemic levels.
“Exposure to air pollution affects the same organs (lung and heart) that are attacked by COVID-19,” she explained, adding that she was unsurprised by the results.
Others agreed that the immediate environmental benefits of lowered air pollution recorded in many parts of the world – while welcome – would be short-lived.
“As quickly as it happened, it will quickly go back to the way it was,” David Lehrer, executive director for the Arava Institute for Environmental Studies, told The Media Line. “But what we’ve shown is that with decisive action, we can impact the greenhouse gases in the atmosphere. We’ve been forced to do it by this pandemic but there are other ways to reduce fossil fuels, which don’t entail the entire world being shut down.”
The Arava Institute for Environmental Studies, located at Kibbutz Ketura in southern Israel close to the Jordanian border, will be giving a short online lecture on the environmental effects of the coronavirus this coming Wednesday as part of international Earth Day celebrations.
“We’ve seen cleaner air in places like Haifa where there’s a lot of industry, and in Tel Aviv,” Lehrer related. “The most important lessons from all of this are that, No. 1, science matters, and when scientific experts tell us something we should listen. Secondly, it’s very clear that we human beings have the ability to impact the situation. … We still have time to do something if we act decisively and most importantly if we act as a global community.”
Lehrer underlined that the immediate environmental changes seen in the past weeks demonstrate that humanity collectively needs to travel less, work from home whenever possible and be less consumer-oriented.
“We need to get back to normal, but [it] needs to be a new normal that recognizes the need to protect ourselves from future pandemics and at the same time considers the medium-term threat of climate change,” he concluded.