A POSITIVE spin-off from the coronavirus crisis has been a sharp decline in air pollution in Winchester city centre.

With most traffic now off the road as thousands of people are staying at home and business is curtailed the usually congested Winchester city centre is enjoying noticeably cleaner air.

The city council estimated yesterday that nitrogen dioxide levels could be 20 per cent down but in similarly congested city centres nationwide declines in pollution of between 10-50 per cent have been reported.

Prof James Lee, of the National Centre for Atmospheric Science, told national newspapers: “The air is definitely much healthier. These are big changes - pollution levels are the equivalent at the moment of a holiday, say an Easter Sunday. I think we will an even starker drop-off when the weather changes.”

Winchester has several measuring stations, on Friarsgate, behind the Chronicle office on St George’s Street and at the top of St George’s Street near the Royal Oak pub.

It has high pollution levels because the small centre sees a high volume of traffic and the city sits in a bowl between hills meaning that, particularly in winter, cold dirty air sinks down into the city centre.

A city council spokesperson said: “There has inevitably been a reduction traffic movements as all but essential travel has been discouraged to try to reduce the spread of COVID-19. Therefore our monitoring stations are starting to show a reduction in the air pollutants released by vehicles. For example, nitrogen dioxide levels for March 2020 were 20 per cent lower than in March 2019, with a more substantial drop towards the end of the month. All data is currently provisional as it has not been fully ratified.”

Jock Macdonald, chairman of Winchester Action of Climate Change, said: “Such good news at this awful time. The streets in Winchester, as elsewhere, are now so empty of vehicles that their pollution from NO2 and particulates has dropped dramatically. World-wide, though, the level of CO2 in the atmosphere, as recorded in climate stations atop mountains like Mauna Loa in Hawaii, is the highest it has ever been in March.”

The dirty air in Winchester district has been linked with worsening many health conditions and contributing to around 50 deaths a year.

Chris Gillham, of Winchester Friends of the Earth, said: “Yes COVID-19 will raise all sorts of questions, many of which will need a lot of thinking about. I know there have been suggestions that the economic devastation of the outbreak might have worse long-term health consequences than COVID itself. I think that is so difficult to assert with accuracy.

“There is the counter argument that business-as-usual capitalism has all sorts of health costs that also ought to be weighed.”

Just on road transport there is the health (40,000 lives and 400,000 lost years of life per annum) and economic cost of pollution (£23billion I think was the government estimate), the cost of accidents and the health cost of inactive lives resulting from overuse of cars. Not to mention climate costs, which will ultimately impact on health as well as economy.”

Mr Gillham said that on pollution in Winchester district the Public Health England report from a couple of years ago gave the mortality for Winchester District as 51 early deaths per year and something like 500 years of life lost. He said central Winchester is probably around six deaths and 60 years of life lost per annum. “It is not easy to compute what the share of pollution is assignable to road traffic, but the drops in the pollution figures are fairly dramatic, suggesting that the majority of the pollution has been reasonably attributed to road traffic in the past.”