The Covid-19 experience generated a great deal of information from attempts to measure its unprecedented effects on the planet. One example is trying to understand whether the spread of the virus has indirectly improved air quality in large, urban areas. This would be a direct consequence of the lockdown, which would have contributed to a reduction in atmospheric emissions, especially particulate matter and nitrogen oxide.
Hard to encode data
The production of CO2 has increased almost constantly over the last 20 years, at an average global rate of 1% every 12 months. 2008 was the only, temporary exception to this. The change has not happened everywhere in the same way. Developed countries who have taken the right course have seen a decrease in greenhouse gas emissions, mainly due to renewables and more efficient use of energy. In the fastest growing economies, among which China and India are out in front, renewables are not replacing fossil fuels, but are used in addition to them. From a global perspective, we could imagine a drop in climate changing gas emissions, especially CO2, corresponding to the drastic halting of a significant part of industrial and transport activities due to coronavirus. Measuring this is not easy though. It is usually done by measuring energy consumption in different countries, taking the amount of fossil fuel used as a guideline. The International Energy Agency are responsible for providing the data and it usually takes about six months to collect, verify and process them, to ensure that they are reliable. As such, their data for 2019 will be available in the middle of this summer and the same time frame would be expected for data relating to the period of the 2020 pandemic.
An alternative approach is needed to attempt to estimate the effects of the coronavirus emergency. One example is from the University of East Anglia, in Norwich. Instead of starting with energy consumption, the researchers looked at data on economic activity and electricity consumption, identifying six sectors that are particularly significant in terms of carbon dioxide emissions: electricity production, industry, surface transport, public services, residential and aviation. Information from 69 countries, including most of China, was compared to the different confinement policies adopted to deal with the pandemic. A confinement index was generated: zero for countries that did not implement restrictions; one for countries that only isolated ill people; two for countries that closed their borders, schools and public places, but not businesses; three for countries that imposed strict restrictions, where most production and commercial activity stopped and people were in lockdown.
Lockdown vs. emissions
The results of processing the data are surprising. On a European level, there was an estimated 26% reduction in CO2 emissions in the February-April period, with peaks of over 30% in France, Spain and Italy where stringent lockdowns were in place. Globally, confinement policies were not the same everywhere and did not happen at the same time. The overall estimated emission reduction was lower, but was still around 7.5%, with a peak of 17% in the first week of April. To put this into perspective, the drop in CO2 emissions during the 2008-2009 crisis was only 1.5 percentage points.
We don’t know how reliable these data are. It will be a year before we can compare them to the official data from the Energy Agency, in the meantime we can only verify their adequacy by comparing them to other similar studies. One from the French climate research laboratory in Gif-sur-Yvette, for example, showed fairly similar numbers. In summary, we would have happily done without the virus, but it has given us a modest and temporary benefit: a cleaner environment.
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