Air quality shows ‘cleaner world’ for Earth Day, study shows
Apr 22, 2020, 10:36 AM
A compilation of data from the Suomi NPP satellite in April and October 2012. Photo NASA
SALT LAKE CITY — A new report from IQ Air shows air pollution levels have dropped dramatically across the world, with unprecedented low levels as celebrations take place during the 50th anniversary of Earth Day.
The study compares the fine particulate matter (PM2.5) — a harmful air pollutant — around the world, before and after lockdown orders were put in place. Researchers found dramatic drops in pollution, noting the worldwide stay-at-home restrictions allowed for the “largest-scale experiment ever” into air quality.
“In many places, the halt of movement and industry has shown a glimpse of a cleaner world, with many reports of exceptional blue skies,” the report said. “Findings reveal a drastic drop in PM2.5 pollution for most global locations under lockdown conditions.”
Some studies have linked poor air quality to a higher likelihood of death from COVID-19, and IQ Air calling air pollution “far deadlier” than the coronavirus — with 90% of the world’s population breathing unsafe air, according to an article posted by the company in February.
“While the new coronavirus is dominating international headlines, a silent killer is contributing to nearly 7 million more deaths a year: air pollution,” Frank Hammes, IQAir CEO, said in a statement. “Through compiling and visualizing data from thousands of air quality monitoring stations, the 2019 World Air Quality Report gives new context to the world’s leading environmental health threat.”
However, with more people staying inside, cities with historically higher PM2.5 levels saw a substantial drop in air pollution.
The report analyzed the change in air pollutants in 10 major global cities:
- Delhi — which was the fifth most polluted city in 2019, according to IQ Air.
- London
- Los Angeles
- Milan
- Mumbai
- New York City
- Rome
- São Paulo
- Seoul
- Wuhan
Researchers collected data from a three-week period when each of these cities was in lockdown from the COVID-19 pandemic. Then, they compared their findings with data from the same time period in 2019, 2018, 2017 and 2016.
They found nine of the 10 cities experienced a drop in air pollution compared to the same time period in 2019, with major drops in Delhi (-60%), Seoul (-54%) and Wuhan (-44%) — which are all cities with historically higher levels of PM2.5 pollution, according to the study.
Additionally, Wuhan reported its cleanest February and March air quality on record during its 10-week lockdown. Similarly, Los Angeles experienced its longest streak of clean air on record, meeting the World Health Organization’s air quality guidelines.
The study links the major drops in pollution to the restrictions of people moving around and the halt of economic activity, which have been imposed in efforts to curb the spread of the coronavirus pandemic.
