- The World Economic Forum has created a visualization of decreased nitrogen dioxide levels in the air thanks to COVID-19 mobility restrictions.
- The visualization shows air quality already worsening in places where economic activity is restarting.
It was good while it lasted – but air quality is already regressing in places emerging from COVID-19 mobility restrictions.
By at least one measure, restrictions aimed at curbing the spread of the coronavirus resulted in dramatic air-quality improvements. Nitrogen dioxide (NO₂) is produced as we burn fuel – it harms human health, decreases visibility, and pollutes air and water. Using satellite imagery, the World Economic Forum has created a visualization of sharply reduced NO₂ levels in places that implemented stay-at-home measures to combat COVID-19. It also shows what’s in store as the world increasingly reopens for business.
Los Angeles, for example, is legendary for its heavy car traffic and poor air quality. The city implemented mobility restrictions in March to combat the spread of COVID-19, including a stay-at-home order and the closure of non-essential businesses. Here we see local NO₂ levels in the wake of those restrictions, ranging from high (dark red) to low (light cream in colour).
Italy has been hit particularly hard by the pandemic. Northern areas of the country went into lockdown starting in late February, and a nationwide measure went into place in early March. Again, high levels of NO₂ are represented here in dark red – and largely disappear over time.
India implemented a nationwide lockdown in late March, giving people just a few hours to stockpile food before it took effect. Here we see a decline in NO₂ levels in the north of the country around that time.
China's example has served as a harbinger of what’s to come throughout the crisis. It was the first country to confirm cases of what became known as COVID-19, it began implementing measures to restrict mobility in January, and it started lifting them in early April. Both a corresponding decline in NO₂ levels – and a discouraging subsequent increase as the economy restarted – are evident here.
For more context, here are links to further reading courtesy of the World Economic Forum’s Strategic Intelligence platform:
- L.A. isn’t the only American city that’s enjoyed cleaner air – according to NASA satellite measurements, NO₂ levels are about 30% lower on average across the region of the I-95 corridor from Washington, D.C. to Boston. (NASA)
- In some ways, the coronavirus crisis has sent what few moves Britain’s cities were making towards cleaner air into reverse, according to this analysis. (CityMetric)
- NO₂ emissions are a particularly thorny problem for Europe, China is normally responsible for more than half of all the NO₂ emissions in Asia, and each tonne that isn’t being emitted now is equivalent to removing 62 cars per year from the road, according to this analysis. (The Conversation)
- Despite evidence that air pollution kills more than 50,000 Americans prematurely every year, the US Environmental Protection Agency has opted against a stricter air quality standard, according to this report. (InsideClimate News)