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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."
Hell, many of them probably wish they could afford to repair or replace the jalopies...sigh, fucking poor people are killing us again.
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway
You have to remember that "Cash for Clunkers" was not intended to reduce emissions. It was intended to provide a short-term stimulus to the auto industry. In that regard it worked for a short time, as intended; however, it led to a situation where the auto industry faced low orders after the program ended because people had just "rescheduled" intended purchases.
There was also the problem that the program was rather restrictive and actually disqualified many of the vehicles that should have been removed from the road if emission reduction had been a goal.
CO2 is in a different category than "air pollution" in the sense that "air pollution" causes health problems (directly), while CO2 only causes climate change.
It's also in a different category because the solution to reducing it is different. In theory, it would be possible to eliminate all "air pollution" other than CO2 from an internal-combustion engine exhaust, if you had the right kind of catalytic converter/filter/etc. on it. In contrast, the only way to eliminate CO2 from an internal-combustion engine is to turn it off.
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
CO2 is not a pollutant but a greenhouse gas.
Otherwise you're making an argument that every time you exhale, you're polluting the air.
When I was just out of college and broke I had a car that was clean and was reliable.
When our state began emissions inspections my car failed and I was required to fix it. The repair estimate was $400 (in 1992) and I didn't have $400 to fix my car, so I had to stop driving it.
I was lucky that of the two part-time jobs I had to make ends meet, one agreed to change the store I worked at to a location within reasonable walking distance AND the hours I worked to accommodate the bus trip I now I had to make every day to my other job (I rode the bus on days I only worked that job anyway).
For a lot of people, though, they just don't make enough money to afford these kinds of repairs and they NEED a car to get to work or school or childcare or whatever their responsibilities are.
Mandating this kind of fine-tuning sounds like a great idea, but it ultimately becomes another punitive burden on low-income people. If I wasn't lucky enough to have the alternatives I had, I would have been out of a job or forced to drive illegally.
That this would be a new idea surprises me. In 2009, the US had the Car Allowance Rebate System (aka Cash for Clunkers) program which likely helped reduce emissions even it was more of an economic program. Further back, twenty years ago Ventura County offered money to get old clunkers off the road strictly for emissions reasons. In 1995 per the article I link below, "More than 50% of the smog comes from vehicle emissions and a large percentage of that comes from older, pre-1974 clunkers." If you look at the distribution of cars, many are late model, well-maintained, and operating at or very near their peak. But as cars age and lose value, newer cars are built to higher emissions (and safety) standards, the parts get worn, routine maintenance gets done but many repairs aren't done because it isn't worth it based on the value of the vehicle. In areas without emissions testing, there is absolutely zero incentive to worry about it with an older vehicle. I realize this every time I get behind a vehicle that is smoking or burns my eyes because it is in such bad shape. This is not even about zero or low emissions, it is simply about getting extreme polluters off the road.
Bottom line: Encourage people to replace clunkers and keep their vehicle well-maintained.
As an odd aside, there are articles that show a similar distribution of costs in emergency room. A small number of patients dominate ER costs in the US because they have no insurance and chronic conditions. Google that one for yourself.
Ventura County Reference: http://articles.latimes.com/19...
A lot was left out of the study. I find their methodology fishy. For example, here's their test area:
Downtown... stop and go for large portions of the day... various driving states... in short, even if two people are driving the exact same car in the exact same condition in the exact same driving style on average, if one at the particular moment of passing the sensor happens to be letting off the gas, while the other just happens to be accelerating when it passes the sensor, the two cars are going to give wildly different pollution readings.
I'll also note that the paper says that it's still in review, aka it hasn't passed peer-review yet.
I'm sure the general premise is right, that small numbers of vehicles cause most pollution. But I think their experimental setup is pretty bad. The stupid thing is they're collecting the data they'd need to control for it - they're taking pictures, which would let them tie vehicle plumes to particular license plate numbers, and then only study vehicles that pass by the sensor a number of times times to that they can get a running average. Another way to control for it would be to have a dozen or so sensors spaced out down the road spaced well apart so that they can average a particular vehicle's emissions on a single drive down the road. But a single sensor, single pass way to rate a vehicle's emissions as good or bad? That's a terrible approach. And they stretch very far on their conclusions based on this approach.
Sigur RÃs: I didn't know that Heaven had a rock band.
Then fix your damn catalytic converter, for fuck's sake!
You know, even if you're an enthusiast there's no excuse not to have a functioning cat. It's not as if it makes more than a negligible difference in horsepower (especially if the car is close to stock). I have a 25-year-old Miata that I use for autocross, and you know what? Even though it's so old that it's no longer even required to meet emissions, all the equipment is still intact, it doesn't smoke, and it doesn't smell. If I had to get it emissions-tested tomorrow, I'd fully expect it to pass with flying colors.
Now, as for your rotor apex seals, those I can't blame you for failing to replace since they require disassembling the engine. But the cat isn't enough trouble to justify neglecting.
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
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.
Concerning such pollutants, we actually don't share the same atmosphere. These sort of pollutants have short atmospheric residence periods, they're mainly problems at or near the point of emission (the particular distance that they pose a problem for depends on the type of pollutant).
It's one of the reasons that even if electric cars didn't cut down in pollution (which studies repeatedly show that they do) and simply moved the same amount of pollution from the streets to the top of power plant smokestacks, they'd still improve public health on average. Any pollutants you do emit, you want them as far as possible away from where most people are (aka, away from areas with lots of traffic, aka, lots of people), and as high up as possible.
Sigur RÃs: I didn't know that Heaven had a rock band.
It's easy to meet EPA standards on test bench. Out in the real world it becomes a lot harder. Heavy acceleration is bound to dump all kinds of particulates, NOx, and CO, despite pollution controls like catalytic converters. Things like catalytic converters and other pollution controls run best under constant conditions, with the proper amount of fuel to air, temperature, etc. All of which probably works well while cruising at constant speed down the open road. The moment you start doing stop and go, all bets are off. Hit the gas pedal hard and the fuel mixture goes fairly rich as the engine tries to keep up. I'm not a hypermiler freak, but I do tend to accelerate and brake conservatively (I have a CDL and drive big trucks occasionally as well, which influences my habits) which seems to anger people in city driving, unfortunately. I also try to take curves in a manner that makes things as smooth as possible.
Most people on the road seem to not care one bit about fuel consumption and race from light to light, without actually getting ahead of anyone doing that, nor actually getting anywhere faster. I'm sure emissions could be curtailed quite a bit if everyone just slowed down and cars limited their acceleration to something realistic.
I imagine these horribly-bad 25% of cars emitting the most pollution would do a lot better if people would drive them properly.
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.