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25 Percent of Cars Cause 90 Percent of Air Pollution
HughPickens.com writes: Sara Novak reports that according to a recent study, "badly tuned" cars and trucks make up one quarter of the vehicles on the road, but cause 95 percent of black carbon, also known as soot, 93 percent of carbon monoxide, and 76 percent of volatile organic chemicals like benzene, toluene, ethylbenzene, and xylenes. "The most surprising thing we found was how broad the range of emissions was," says Greg Evans. "As we looked at the exhaust coming out of individual vehicles, we saw so many variations. How you drive, hard acceleration, age of the vehicle, how the car is maintained – these are things we can influence that can all have an effect on pollution." Researchers at the University of Toronto looked at 100,000 cars as they drove past air sampling probes on one of Toronto's major roads. An automated identification and integration method was applied to high time resolution air pollutant measurements of in-use vehicle emissions performed under real-world conditions at a near-road monitoring station in Toronto, Canada during four seasons, through month-long campaigns in 2013–2014. Based on carbon dioxide measurements, over 100 000 vehicle-related plumes were automatically identified and fuel-based emission factors for nitrogen oxides; carbon monoxide; particle number, black carbon; benzene, toluene, ethylbenzene, and xylenes (BTEX); and methanol were determined for each plume. Evans and his team found that policy changes need to better target cars that are causing the majority of the air pollution. "The ultrafine particles are particularly troubling," says Evans. "Because they are over 1,000 times smaller than the width of a human hair, they have a greater ability to penetrate deeper within the lung and travel in the body."
CO2 emissions are proportional to fuel consumption, so I guess there's no point measuring that figure; the fuel efficiency of vehicles is a known quantity. I guess it would have been interesting to have CO2 figures included for comparison with the other numbers though.
CO2 level was actually used to automatically identify the exhast gasses in the study, so maybe they actually had those figures, without reading the full paper it's hard to say. From the abstract;
"Based on carbon dioxide measurements, over 100 000 vehicle-related plumes were automatically identified and fuel-based emission factors for nitrogen oxides; carbon monoxide; particle number, black carbon; benzene, toluene, ethylbenzene, and xylenes (BTEX); and methanol were determined for each plume."
Oh no... it's the future.
And the several percent of non-vegans who travel by bicycle instead of cars are acting all smug thinking they're saving the planet, when their consumption of meat for the calories they burn gives them the per-kilometer carbon footprint of an SUV. Plus an order-of-magnitude higher per-kilometer risk of death or serious injury than a person in a car.
Sigur RÃs: I didn't know that Heaven had a rock band.
CO2 emissions are proportional to fuel consumption, so I guess there's no point measuring that figure; the fuel efficiency of vehicles is a known quantity.
But are these vehicule really causing 90% of the pollution? Maybe it's only 35% when you count CO2 who knows?
Some of the listed pollutants are the results of incomplete combustion. It's worthwhile to include CO2, since there's a very good chance that the offending vehicles may therefore be releasing less waste in CO2 form.
This isn't new, I've read articles on it (in California) over 20 years ago. Inspections work when a large percentage of your cars are emitting an excessive amount of pollutants. But as that percentage decreases, you end up wasting huge amounts of money.
Say an inspection costs $25 and 1 in 10 cars is not in compliance. You're basically paying $250 to detect each polluting car and require it be fixed. That's probably a worthwhile tradeoff.
Now fast-forward. After decades of inspections have successfully weeded out the worst-polluting cars, only 1 in say 1,000 cars is not in compliance. You're now siphoning $25,000 out of the economy to detect each polluting car. There's no way that's worth it.
California is pretty much already in that second state. 20 years ago the companies that make the emissions testing equipment suggested a much more financially sensible solution. Stop the inspections or reduce them to random lottery inspections which would hit each car on average every 10 years - the vast majority of cars are already clean enough and there's little to be gained from annual or bi-annual inspections. Instead, place detection equipment like used in TFA on places where cars pass by single-file, like freeway on-ramps. This equipment would automatically measure the emissions of each passing car (or truck), and if a particular car was dirty it would snap a photo of the license plate. If a car was flagged repeatedly at multiple stations, the State could then issue the owner a notice requiring him to fix it.
But the idea never got anywhere because the auto repair shops lobbied heavily against it. See, these inspections have become a billion dollar business, and they didn't want to lose that money. One person wasting money is another person making easy money.