Analysis of world-wide data by the UK-based website Carbon Brief has suggested that the coronavirus pandemic could result this year in cuts in emissions of carbon dioxide (CO2) in the region of 2,000 million tonnes, equivalent to around 5.5% of the current global total. This would trigger the largest annual fall in CO2 emissions ever recorded – though still not enough to make much of an impact in bringing the 1.5°C global temperature limit within reach.

It’s not just CO2 emissions which have plummeted.  Other data sources reveal marked reductions in the principal pollutants of air, nitric oxide (NO2) and particulate matter (PM), as well as bringing significant improvements in visibility.

In Europe, measures to combat the coronavirus have led to a 40% reduction in the average level of NO2 and a 10% reduction in PM pollution during the month of April compared with March, resulting in more than 10,000 avoided deaths from air pollution, most notably in Germany, the UK, Italy, France and Spain. This effect comes as power generation from coal and oil combustion – still the main sources of NO2 and PM pollution across much of Europe – has fallen by 30% or more.

As it takes several weeks to gather data and generate reliable results from manually operated NO2 diffusion tubes and particulate monitors, the only sources of data available for the current period in the Borough of Merton are the two automated stations monitored by Kings College, University of London.

Although the 2020 data has yet to be fully verified, a noticeable reduction in NO2 levels is apparent since mid-March, probably because this pollutant is produced primarily by vehicle exhausts, and traffic across the borough has decreased considerably in recent weeks.