Researchers at the Climate and Atmosphere Research Center (CARE-C) of The Cyprus Institute have used data from the continuous monitoring of major pollutants by the Air Quality section of the Cyprus’ Department of Labour Inspection to investigate air quality in Nicosia during the recent COVID-19 lockdown. The researchers tried to determine the extent the decrease of traffic emissions affected levels of air pollution in the urban environment.
Preliminary results show that the unprecedented lockdown measures taken in the battle against coronavirus (COVID-19) have triggered a major decrease of air pollution due to local traffic emissions in Nicosia. The researchers focused on two pollutants, carbon monoxide (CO), which is derived from the incomplete combustion of carbon-containing fuels, including those from traffic and biomass burning, and nitrogen oxides (NOx), which come almost exclusively from fossil fuel use.
Data were obtained in February, March and April 2020 and compared to those obtained for the same months in 2019 from two sites. Measurements made close to a (usually) busy, traffic-heavy road in Nicosia (Nicosia Urban Traffic) demonstrated that CO and NOx levels decreased by 95 ppb (28%) and 13 ppb (57%), respectively, since the start of the lockdown. Similarly, measurements made in the Nicosia urban background (i.e. a residential area of the Strovolos’ municipality, away from busy roads) indicated that CO and NOx levels decreased by 51 ppb (23%) and 11 ppb (67%), respectively, since the start of the lockdown. Daily (24hr) averages for the two sites are reported in Figure 1.
Further to these preliminary findings, a more exhaustive evaluation of the air quality impacts of the lockdown will be performed considering a wider range of air pollutants (e.g. fine particles), remote sensing (satellite-borne) observations, and atmospheric modelling approaches.
Air pollution and public health
In a 2019 paper co-authored by Prof. Jos Lelieveld, Head of the Environmental Predictions Department of CARE-C, at The Cyprus Institute and Director at the Max Planck Institute for Chemistry, scientists estimated that nearly 800,000 people die prematurely each year in Europe because of dirty air (more than 1,100 in Cyprus), and that the life of each citizen is cut short by an average of more than two years. Air pollution, especially particulate matter, can cause respiratory and cardiovascular diseases, causing premature deaths.
In a recent study co-authored by Prof. Lelieveld, examining air pollution declines due to COVID-19 lockdowns and their implications for public health, it was estimated that up until mid-May, in 34 countries about 50,000 premature deaths and nearly 90,000 pediatric asthma emergency room visits have been avoided, which can be seen as a health co-benefit of the containment measures.
The tragic circumstances that brought about the lockdown and the consequent economic downturn are of course neither desirable nor sustainable, but these findings showcase the potential public health benefits of reducing what we long considered “business-as-usual” air pollutant emissions prior to the pandemic.
According to Prof. Lelieveld, “Reducing air pollution in the long-term in a sustainable way will require that the burning of fossil fuels is phased out. This would improve the health of people both locally and globally by the reduction of air pollution and climate change”.