Hidden climate killer: how soot from fires and fossil fuels is quietly accelerating global warming

While carbon dioxide gets most of the attention in climate discussions, a lesser-known pollutant is quietly wreaking havoc on both human health and global warming. Soot—also known as black carbon—is a fine black particle released when forests burn and fossil fuels are consumed, and it’s proving to be one of the most dangerous overlooked threats of our time.

A powerful new photo series by award-winning photojournalist Victor Moriyama, created in partnership with the Clean Air Fund, reveals the devastating impact of soot across Brazil. During 2025, following some of the country’s driest years on record, Moriyama traveled from the Amazon rainforest to rural southeastern communities, documenting how this “super-pollutant” affects daily life. The timing couldn’t be more critical—as climate change intensifies fire seasons worldwide, soot pollution is becoming an increasingly urgent crisis.

The numbers are staggering: soot contributes to at least 8.1 million premature deaths globally each year, including 700,000 children under age 5. Beyond its immediate health impacts, soot accelerates climate change by darkening surfaces where it settles, causing them to absorb more heat from the sun. These particles can remain suspended in the atmosphere for weeks or months, spreading far from their original source and affecting communities that may be hundreds of miles from the nearest fire.

Despite this mounting evidence, soot remains dramatically underfunded in climate action efforts. According to the Clean Air Fund’s latest report, only 1% of international development funding between 2019 and 2023 supported clean air projects, including initiatives targeting black carbon pollution—a glaring oversight that demands immediate attention.