Crude oil. It’s really a stew of various hydrocarbons. And when the oil started spewing into the Gulf of Mexico last year, some stew ingredients were able to take to the air—in two distinct groupings. That’s according to research published in the journal Science.

Evidence for the atmospheric incursions was captured by NOAA's hurricane hunter airplane on two flights last June. The first oil trail was a three-kilometer wide downwind plume made up of the crude’s lightest hydrocarbons. They evaporated once the slick hit the surface. The second atmospheric smudge consisted of heavier, rarer compounds that took days to evaporate—but then formed a 40-kilometer wide plume chock full of tiny particles.



That plume might affect oil spill cleanup workers who were out on the water. The tiny particles can damage the heart and lungs. More generally, anyone concerned about the nation’s urban air quality ought to be looking at the same particulates coming out of cars. We don’t currently track these substances because it was thought they would be too rare to cause harm.



What happened to the two atmospheric plumes? Well, what goes up usually comes down. In this case, in rain. Dropping the compounds on land—or back in the sea.

—David Biello