The significantly cleaner air being breathed in the UK in recent months is likely to deteriorate over the coming week as the lockdown eases on Monday, triggering a surge in road traffic.
Many other countries which have eased restrictions enforced at the height of the coronavirus pandemic have since seen numbers of vehicles on the roads soar to record levels.
As many shops and workplaces open for the first time since 23 March on Monday, pollution levels are expected to climb and the number of road accidents is likely to rise.
In China, as restrictions have eased and travel and industry resumed, air pollution is now overtaking the levels prior to the pandemic.
In Wuhan, where the outbreak began, car use is now hit levels higher than before the pandemic, and the same is true of Stockholm in Sweden.
As lockdown measures have eased, authorities in cities around the world have warned against people crowding onto public transport where they could inadvertently cause another wave of coronavirus infections.
The result is that commuters who may usually have opted for public transport may use personal cars more, experts have suggested.
“The problem is going to be that all these forms of transportation are competing for the same amount of finite space,” Sam Schwartz, a transit consultant and former New York City traffic commissioner, told Business Insider.
“Even at 50 or 60 per cent of a full reopening of a city… what we’re going to see is perhaps 100 per cent or more of automobile traffic.”
A global survey of more than 11,000 drivers in 11 countries found the pandemic has led to an overall increased interest in car ownership, including among younger buyers and those who have never owned a car before.
And a study by academics at Vanderbilt University titled “The Rebound: How Covid-19 could lead to worse traffic” also indicated the easing of lockdowns could lead to a spike in congestion.
The paper states: “Cities that depend on transit are at risk for extreme traffic unless transit systems can resume safe, high throughput operations quickly.”
Global carbon dioxide emissions fell by as much as 17 per cent as a result of lockdowns imposed around the world in response to the coronavirus crisis, according to a study published last month.
At the peak of lockdown, daily CO2 emissions on 7 April temporarily dropped to levels last seen in 2006.
Overall the researchers found that global emissions could fall by up to 7 per cent this year, depending on ongoing restrictions and social distancing measures during the coronavirus pandemic.
The sharp drop represents the biggest fall in carbon emissions since records began.
Though a spike in traffic and congestion is expected, most people want authorities to take action to help commuters use active travel and public transport to maintain the clean air they have enjoyed recently.
Almost three in four people in six European countries said they wanted city authorities to take action to provide better air quality, according to a survey this week by YouGov.
“People felt in their own lungs how clear the air can be,” said Jens Muller, air quality manager at Transport & Environment, a European umbrella group of NGOs campaigning for cleaner transport, which supported the study.
“So now we see a strong support for measures, where before they weren’t always super popular, like taking away space for cars, banning polluting cars, from city centres.”
The poll was based on online interviews with more than 7,500 people living in 21 cities including Madrid, London and Berlin.
It found 60 per cent of respondents favoured reserving more space for public transport, for example by expanding bus lanes. About the same share, 62 per cent, wanted to see more cycling lanes, while one in three backed more pedestrian paths.
But respondents were less keen when it came to changing personal habits. Only 21 per cent said they planned to cycle more after the lockdown while 35 per cent said they would walk more.
Better infrastructure, such as wider pavements and segregated cycling routes, could persuade more people to join, said Lucy Mahoney, network manager for walking and cycling at the C40 network of cities pushing for swift climate action.
“Cities ultimately need to make public space feel safer for people to walk and to cycle, and to prioritise them above vehicles,” she told Reuters.
Milan, London and Paris were among cities that had already moved in that direction, with plans and investments to cut traffic and encourage riding, she said.
“What is needed at this time is a concerted effort to address race-related barriers to walking and cycling in cities worldwide,” Ms Mahoney said, referring to demonstrations for racial equality that have swept the globe.
“Black and minority ethnic groups are hugely underrepresented in cycling, so real investment is needed.”
Valentine Quinio, a researcher at British think tank Centre for Cities also suggested the coronavirus risk could cause higher levels of pollution due to congestion.
“There’s a risk that air pollution actually not only goes back to previous levels, but goes higher, because people are likely to jump in their cars,” she said.
Additional reporting by Reuters
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