Jet exhaust and sunlight mix to form high levels of pollution

Jet engine exhaust, through a chemical reaction catalyzed by sunlight, is transformed into ultrafine particle pollution at a rate much higher than previously thought, according to a new study.

In the wake of the study, airports with idling jet aircraft may come under increased scrutiny as sources of local pollution.

“It sort of blew our minds,” said Allen Robinson, lead researcher of the Carnegie Mellon University team that published the research in the journal “Atmospheric Chemistry and Physics.”

The researchers determined that jet engine exhaust, in the presence of sunlight, is transformed into dangerous ultrafine pollution particles at a rate 35 times greater than the engine originally emitted and 10 times greater than computer models.

“Models that do not account for this processing will likely underpredict the contribution of aircraft emissions to local and regional pollution,” the research team concluded.

The increase in pollution particles was noted especially at low load levels when engines are idling. This fact might cause increased concern for air quality near larger airports where jet aircraft idle for longer periods of time.

The study will likely generate increased attention to the role of airports as a significant source of local air pollution, especially within a few kilometers of the airport.

Previous research has measured jet emissions but never took into account the action of sunlight on the emissions.

Download the full report, “Secondary aerosol formation from photochemical aging of aircraft exhaust in a smog chamber,” here.