Pollution

City's air quality improves during pandemic

New data has shown that air quality in Cambridge city centre has improved during the lockdown, with nitrogen dioxide levels 33% lower than the average for the previous three years.

Exhaust
BBC

The report, about the impact of travel restrictions on traffic and air quality on the Greater Cambridge transport network was developed by the Greater Cambridge Partnership and gives an initial assessment of how people moved around the city between 16 March and 19 April.

It also shows:

  • A 56% reduction in average daily motor vehicle journeys, with significant drops in bus and delivery vehicle movements
  • Daily use across all multi-storey car parks dropped by 83%
  • An average decrease of 39% in daily cycle counts and a 26% drop in daily pedestrian counts across monitored locations – which reduced by 80% in retail areas
  • A large reduction in bus services and bus users
  • Journey times improved by an average of 27% across monitored routes

Lockdown 'halves pollution' in central London

A general view of the city skyline on May 01, 2020 in London
Getty Images

London has seen levels of key pollutant nitrogen dioxide fall by more than half in some places due to less road traffic in the lockdown, research shows.

Research from King's College London found concentrations of nitrogen dioxide (NO2), which largely comes from burning diesel and petrol in vehicle engines, have come down by as much as 55% due to a fall in traffic on the road.

The average hourly concentrations of the pollutant have fallen more than a fifth (21.5%) across the capital.

The normally busy Marylebone Road saw levels of nitrogen dioxide fall 55% and concentrations of the pollutant was down more than a third (36%) on the Euston Road.

But levels of tiny polluting particles known as PM10 and PM2.5 were higher after the lockdown was brought in than at any other time so far this year, as easterly winds carried pollutants from northern Europe.

The researchers also warned that some people will have been exposed to higher levels of PM2.5 pollution indoors because of more time spent cooking at home.

Professor Martin Williams, head of science policy and epidemiology team at King's College London, said: "Our early analysis of the lockdown showed significant reductions in nitrogen dioxide - particularly near busy roads in London where in some central areas concentrations were halved.

"More research is needed to assess how air pollution affects health during lockdown and the role of air pollutants in the spread of the virus."

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