The planet has been changed in a matter of months. Thousands of people have already died, and hundreds of thousands more have fallen sick, from a coronavirus that was previously unknown until it emerged in Wuhan City in December 2019. For millions of people who haven't contracted the illness, their way of living has shifted suddenly.
The streets of Wuhan, China, are abandoned after a tight lockdown has been carried out by the authorities. The most severe travel limits in Italy have been in place since the Second World War. Throughout London, the normal busy cafes, bars and theaters were closed, and residents were ordered to sit throughout their houses. Flights are cancelled or turned around in mid-air globally, as the airline industry buckles.
It's all targeted at reducing the spread of Covid-19 and potentially raising the death toll. Yet all of this transition has also led to some unintended results. Since factories, rail networks and companies have closed down, there has been a sharp decrease in greenhouse emissions.
So, if there's a sliver of positive news, it's about how the introduction of the latest coronavirus has reduced air emissions, and probably saved lives in the process.
In China, pollution declined by 25 % at the beginning of the year as people were forced to sit at home, factories shut down and coal consumption plummeted by 40 % in China's six biggest power plants since the last quarter of 2019. According to the Ministry of Ecology and Environment, the proportion of days of "healthy quality weather" rose by 11.4% relative to the same span last year in 337 cities across China. According to data from the Hong Kong University School of Public Health, primary air pollution fell by about a third from January to February in Hong Kong.
Across Europe, satellite photographs indicate that nitrogen dioxide (NO2) emissions are fading away from northern Italy. The same story is being acted out in Spain and the United Kingdom.
Cities around the world are experiencing record lows in air emissions. Owing to the mitigation steps introduced during the latest COVID-19 outbreak, the atmospheric level of nitrogen dioxide (NO2) – one of the major traffic-related contaminants in our cities – has decreased by between 70% and 80% in Barcelona since 21 March, according to data from the Catalan government.
A research by the Universitat Politècnica de València (UPV) reports that the total decrease in air quality in the major cities of Spain is as high as 64%. Different decreases are recorded in numerous other cities in Europe and around the world: the levels of NO2 in London have decreased by approximately 40% and the levels of carbon monoxide (CO) in New York have decreased by approximately 50%.
Europe’s emissions declines are not as drastic as China's, but they are still significant. Some interesting changes can be seen in electricity consumption, as in Italy is down by about 20% and in Spain and France by about 10%. In some regions of Poland, however, the amount of nitrogen dioxide remained fairly high during the time, despite its shutdown, possibly due to the prevalence of coal-fired heating.
Yet this short-term stall in our fossil-fuel-burning system is just a tiny blip in our overall upward increase in greenhouse gas emissions. If anything, the drop of aerosols — fine particles that contain soot from combustion — may only generate a slight amount of heat this summer. Although the particulate matter is obviously harmful for our safety, these aerosol particles also have a minor cooling influence in the atmosphere. (There is a risk that the impact will be unremarkable, and within the normal variability of the climate).
The fear is that, while decreased air pollution may contribute to health benefits in the short term, emissions may increase once the crisis is over and, in the meantime, climate change may be overshadowed as policymakers concentrate first on slowing the spread of the virus and then on jump-starting stalled economies. The concern appeared to be thoroughly warranted on 1 April, when the UK Government declared that the COVID-19 situation had forced to postpone the proposed COP26 Global Climate Summit, scheduled to take place in Glasgow in November, until an undetermined date next year.
Global emissions may still decline by 0.3 per cent overall in 2020 – less dramatic than the 2008-09 crisis.
What matters, though, is what we do next. In fact, economic downturns continue to lead to short reductions in pollution. Global carbon dioxide emissions fell by around 2% from previous years during the Global Recession of 2008-2009. Yet after that, we went right back to polluting oil, with global pollution increasing in years to come. Following the slowdown, China spent heavily in infrastructure as part of its response, generating vast volumes of steel and cement—large sources of greenhouse gas emissions.
Boosting economic activity after the coronavirus lockout does not mean that ecological goals need to be overlooked. New methods of generating and storing solar energy, hydrogen fuel and other green technologies may prove more appealing to private investors and governments than conventional coal-mining industries, whereas the shutdown of coronavirus may signal a gradual change towards sustainable technology and renewables.
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