Wildfires that charred millions of acres in the West wiped out the country’s pandemic-related clean air gains in 2020, according to a report released this week.
Because pandemic restrictions limited travel and other activities, fine-particle pollution from the burning of fossil fuels dropped 13 percent between March and July compared to the previous year and dipped again in November and December, said Lauri Myllyvirta, lead analyst at the Centre for Research on Energy and Clean Air, who collaborated on IQAir’s annual World Air Quality Report.
But the 2020 historic wildfire season more than made up the difference. Overall, the U.S. average for the deadliest type of air pollution rose nearly 7 percent over 2019 because of smoke from fall fires, primarily those in California, Oregon and Washington.
Fine-particle pollution refers to bits that are 2.5 microns in diameter or smaller, or less than one-20th the diameter of a human hair. These particles are tiny enough to penetrate deep into lungs and enter the bloodstream, where they can trigger asthma attacks and other lung and heart problems and may cause cancer.
