For a state that pioneered second-hand smoke laws, California doesn’t seem to have any problem blowing smoke at its neighbors.
Record wildfires across the state are blasting soot into the atmosphere, where winds carry it to neighboring states, some of which are suffering their own wildfires, or out to sea. NASA monitors the flow of so-called aerosols, or tiny airborne particles, and last week, its Earth Observatory, an arm of the agency that shares images of Earth with the public, published a visualization that combines measured data with its computer models.
The image shows wildfire smoke from the American West, including Canada, sprawling out across the continent. Meanwhile, in Central Africa, agricultural burning contaminates skies there on a similar scale.
The wildfires’ soot, or black carbon, shown in the image consists of tiny particles of un-burned matter. Breathing it is harmful to people and animals.
The spread of the soot is likely to alarm environmentalists.
Soot also has a climate impact: while it floats through the atmosphere it can absorb solar energy, as does carbon dioxide, and contribute to atmospheric warming. But unlike carbon dioxide in the atmosphere in gas form, black carbon eventually settles down to the surface, so its climate effects are shorter-lived.
Aerosols, like those visible in the NASA image, aren’t lifted into the skies by human activity alone. Wind can pick up desert dust and even sea spray, carrying it for similar distances. Europe, for example, gets blanketed a few times a year in a fine Saharan dust.
And NASA isn’t the only one interested in tracking aerosols. A Slovenian entrepreneur and pilot, Matevž Lenarčič, has flown aerial missions to collect aerosols all around the world, including over the poles.