UNEP's novel 'World Environment Situation Room' provides real-time data on PM2.5 levels across the planet, informing scientists, policy-makers and citizens alike.
Last month, as wildfires continued to rage across the American West, Pascal Peduzzi, a climate scientist with the United Nations Environment Programme (UNEP) in Geneva, followed the situation with air quality in Mammoth Lakes, a town high in California's Sierra Nevada mountains.
On Wednesday 23 September on the town's Ranch Road the PM2.5 measurement - the tally of airborne particulate matter with a diameter less than 2.5 micrometres - reached 501mg per cubic metre (µg/m3) of air. That is over 50 times the threshold that the World Health Organisation (WHO) considers safe for the average PM2.5 reading over one year. It is more than 20 times the level considered safe for a 24-hour period.
"I've never seen it that high," Peduzzi stated.
The scientist was not in California, nor in the US. He was in Switzerland, over 9,000km away. Nonetheless, he, and anyone with an internet connection, can now follow in detail PM2.5 levels in the West Coast fire zone, and across the planet, via UNEP's World Environment Situation Room (WESR). This online portal offers a near-real-time monitor of global air quality.
"The intention of this platform was to connect to people," said Sean Khan, an expert on air pollution with UNEP in Nairobi. "It was designed to inspire and stimulate action, whether that's communities trying to convince policymakers to do things or vice versa."
In August, following record-breaking high temperatures, lightning strikes from severe thunderstorms ignited fires in California, Oregon and Washington. By the end of September, these blazes had consumed over 2 million hectares of land across the three states. They had destroyed over 7,000 structures and left at least 40 people dead.
"We now currently have five active fires that are five of the most destructive fires in the history of the state," Gavin Newsom, the governor of California, said on 11 September, standing in smoky air among scorched trees.
The fires threw fine particulate matter into the atmosphere. Alongside producing the extraordinary orange skies seen in television reports, studies have linked elevated PM2.5 levels with a range of health problems. These include asthma, respiratory inflammation, jeopardised lung function and even cancer.