42% decrease in Nitrogen dioxide pollution over 5 years
An analysis of the annual data for Nitrogen dioxide by the City of London Corporation show a 42% drop in levels in the Square Mile since 2016. This statistic, and the year-on-year improvement over the last 5 years, was determined using data from three continuous air quality monitors at Beech Street, The Aldgate School and Walbrook Wharf.
The improvement in air quality is due to a range of air quality measures in place and the response to the COVID-19 pandemic. One such measure is the Ultra Low Emission Zone (ULEZ), established by the Greater London Authority (GLA) in Central London in April 2019, and expanded to the North and South Circular in October 2021. Data assessing the impact of the expanded ULEZ shows that in the first month 92% of vehicles in the zone complied with the ULEZ standards and there was a 1% average reduction in the number of vehicles on the road.