14 DAY TRIAL // Scientists based at the University of California in Irvine (UCI) say that gas particles in the atmosphere tend to get sucked up by smog particles, and then remain trapped there for prolonged periods of time.
One of the most interesting implications of this research is that it may provide an accurate, albeit unexpected, explanation for why existing air pollution models appear to underestimate organic aerosol concentrations in the atmosphere by such a wide margin.
This discrepancy has always baffled researchers, who could not pinpoint the missing factor that was skewing up their models. The new study revealed that smog particles may be extremely efficient at sucking up airborne gases from the atmosphere, and then trapping them almost permanently.
Details of the investigation appear in the February 21 issue of the esteemed journal Proceedings of the National Academy of Sciences (PNAS). The team says that models compiled by everyone from air regulators to the US Environmental Protection Agency (EPA) yielded the same results.
That is to say, all their results were off by a wide margin, in terms of estimating the amount of organic aerosols in the air. According to previous studies, organic aerosols make up an important part of smog particles. The latter are responsible for the ugly haze covering heavily-polluted areas.
Smog particles have also been associated with an increased incidence of asthma among people living close to highways and factories. The particles also increase risks of suffering heart attacks. In addition to the threat they pose to human health, they are also one of the biggest unknowns in climate science.
Smog is known to affect the patterns in which heat is transferred to and from the surface. It can influence the development of cloud covers over particular areas, and can even lead to shifts in precipitation patterns.
“You can’t have a lot of confidence in the predicted levels right now. It’s extremely important, because if the models do a bad job of predicting particles, we may be underestimating the effects on the public,” researcher Veronique Perraud explains.
She is the lead author of the new study, and holds an appointment as an assistant project scientist in the lab of UCI air chemist Barbara Finlayson-Pitts.
“The conclusions are highly significant,” comments Purdue University atmospheric chemist Paul Shepson, who was not a part of the study. He reviewed the data the UCI team submitted for publication in PNAS.
“This paper should – and, I expect, will – have a big impact. We’ve known for nearly a decade that there’s a huge difference between what’s in the models and what’s actually in the air,” he adds.