UK lockdown and air pollution: Nitrogen dioxide halved but sulfur
dioxide doubled

Date:
September 23, 2020
Source:
University of Liverpool
Summary:
A new study of air pollution in the United Kingdom during the
first 100 days of lockdown has revealed that while nitrogen oxide
levels were cut by half, levels of sulfur dioxide increased by
over 100 percent.



FULL STORY ==========================================================================
A University of Liverpool study of air pollution in the UK during the
first 100 days of lockdown has revealed that whilst nitrogen oxide levels
were cut by half, levels of sulphur dioxide increased by over 100%.


========================================================================== Researchers from the University's School of Environmental Sciences
analysed data from the Department for Environment, Food & Rural Affairs
(DEFRA) air- quality sensors and UK Met Office stations to see how
lockdown measures had affected levels of nitrogen dioxide, sulphur
dioxide, particle matter (PM2.5) and ozone, and compare it to data from
the past seven years.

The study revealed that during this period (from 23rd March to 13 June
2020) nitrogen dioxide (NO2) levels were cut by half which would relate
to the reduction in vehicle emissions. More surprisingly, though, the
analysis found that levels of sulphur dioxide (SO2), typically created
by UK industry but in sharp decline, were more than double that of
previous years.

Researchers also explored the localised effects of lockdown on
air-quality, on seven large UK cities: London, Glasgow, Belfast,
Birmingham, Manchester, Newcastle and Liverpool.

This revealed that NO2 levels in all of the cities reduced on average
between 37 -- 41% although it was these reductions were slightly greater
in Glasgow declining by 44%. However, northern cities were found to
experience greater increases in sulphur dioxide.

Lockdown in the UK came into effect on 23 March 2020 when the Prime
minister, Boris Johnson, told the country that people 'must' stay at
home and certain businesses must close.

This resulted in the significant reduction in motor vehicle usage with
the first day of lockdown seeing a reduction to 69% of normal. This
reached a low of 23% on 13 April before steadily increasing back to 77%
100 days after the lockdown. The first 100 days of lockdown also coincided
with higher temperature and less humidity.

Lecturer in contemporary and dynamic processes, Dr Jonny Higham, who
led the study said: "The results of our analysis are surprising. It is
evident that the reduction in motor vehicles and human activity had a substantial impact on air quality as demonstrated by the reduction in
nitrogen oxide. However, although it reduced one pollutant there has
been a big increase in another pollutant.

"We think these changes could be driven by an in-balance in the complex
air chemistry near to the surface exacerbated by the meteorological
conditions in particularly low humidity levels and changes in pollutions concentrations.

"It is important to note that the complex and relatively stable air
composition in the near surface layer can be disrupted in a short period
of time by the significant reduction of primary emissions from human activities. For the case of UK, getting cleaner air from a large NO2
reduction may not be as straightforward as it seems."

========================================================================== Story Source: Materials provided by University_of_Liverpool. Note:
Content may be edited for style and length.


========================================================================== Journal Reference:
1. J.E. Higham, C. Acosta Rami'rez, M.A. Green, A. P. Morse. UK
COVID-19
lockdown: 100 days of air pollution reduction? Air Quality,
Atmosphere & Health, 2020; DOI: 10.1007/s11869-020-00937-0 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/09/200923124758.htm

--- up 4 weeks, 2 days, 6 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)