During a special airborne mission to study the air-quality impacts of the BP Deepwater Horizon oil spill last June, NOAA researchers discovered an important new mechanism by which air pollution particles form. Although predicted four years ago, this discovery now confirms the importance of this pollution mechanism and could change the way urban air quality is understood and predicted. The NOAA-led team showed that although the lightest compounds in the oil evaporated within hours, it was the heavier compounds, which took longer to evaporate, that contributed most to the formation of air pollution particles downwind. Because those compounds are also emitted by vehicles and other combustion sources, the discovery is important for understanding air quality in general, not only near oil spills. Read More