AQESHOW - Abstract

Abstract Information :

The COVID-19 lockdown measures introduced in March 2020 resulted in very large reductions in road traffic levels and corresponding changes in road traffic emissions compared with established emissions inventories. It is important to understand the causes of these changes, some of which may have long-term impacts, for example increased home-working. Emissions inventories take time to collate, but estimates of emissions changes are needed in the short term, for example for air quality forecasting. As part of the Breathe London Pilot project, CERC have been working since the start of the pandemic to quantify the impact of lockdown measures on emissions and air quality in London. Bayesian based inversion techniques have been developed to combine hourly modelled NOX concentrations from the very high resolution ADMS-Urban model with hourly NOX measurements from the AQE, LAQN and AURN reference-standard networks and from the Breathe London network of AQMesh sensors. The result is an assessment of the de-weathered impact of the COVID-19 lockdown on NOX and NO2 concentrations in London and an estimate of the associated impact on NOX emissions from individual sources across London including road and heating sources.