- 2 decades of air quality gains in western U.S. wiped out by wildfires. Black carbon concentrations have risen 55% on an annual basis, mostly due to the wildfires. The fires have also caused an increase of 670 premature deaths per year in the region in the two-decade span. https://www.thelancet.com/journals/lanplh/article/PIIS2542-5196(23)00235-8/fulltext 5 comments science