Ottawa, Ontario – Air quality may be worse than previously thought, according to a new study by Environment Canada, as reported by the Green Car Congress.
The real-time measurement of black carbon (BC) using two laser-induced incandescence techniques has found that emissions from light-duty gasoline vehicles are at least a factor of two higher than previous North American measurements, and a factor of nine higher than currently-used emission inventories in Canada.
Emission factors measured with the incandescence techniques have not been previously reported, according to the authors, who said that these measurements have higher sensitivity and time resolution compared to traditional BC measurement techniques. The studies were done upwind, downwind, and while driving on a highway dominated by gasoline vehicles.
The BC emission factor for heavy-duty diesel vehicles reasonably matched previous measurements. The research team said that this suggests that greater attention needs to be paid to BC from gasoline engines to obtain a full understanding of its impact on air quality and climate.
Black carbon is combustion particles consisting primarily of solid soot cores. It can have a large effect on visibility, has been linked to health issues, and contributes to poor air quality. Evidence suggests that BC deposition in the Arctic is partly responsible for arctic climate change.