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Air pollution fell substantially as Paris restricted car traffic

washingtonpost.com

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Re: Air pollution fell substantially as Paris restricted car traffic

#81

Post by flomo »

SequoiaHope wrote: post #57
jfengel wrote: post #39

Earlier quoted context omitted.

It is, though the problem predates the cars. At the time cars were seen as a huge win over the vast piles of horse poop. Cities do need to be reconsidered for more public transit and more opportunities to walk, but other issues (delivery, emergency, disability, etc) have to figure in.

There was a time in between, where electric streetcars (trains) were a common mode of transport. But those got torn up for cars. That’s a real tragedy in hindsight.

That's the myth. Streetcars were actually torn up because busses were much cheaper, there was no conspiracy. The streetcars were also old and cold and ppl hated them.

(I lived in a streetcar part of SF, and loved it, fwiw. But the only reason it's still there is a tunnel.)

Re: Air pollution fell substantially as Paris restricted car traffic

#82

Post by lostlogin »

azinman2 wrote: post #22
10-1-100 wrote: post #16

Earlier quoted context omitted.

Also worth noting that with modern emissions standards (and transition to EVs), over 50% of handful particulates come from tires, brakes, road surface wear, and resuspended dust: https://www.oecd.org/en/publications/non-exhaust-particulate... I don't think there's any healthy level of private cars coexisting with humans in a city, without even considering the more immediate harms from crashes, etc.

Wonder if anyone is working on ways for breaks and tires to be less harmful, or polluting?

Regenerative braking helps with brake dust, but is probably offset by extra tyre wear on EVs. I go weeks without using the brakes and usually don’t even touch the brake pedal.

Re: Air pollution fell substantially as Paris restricted car traffic

#83

Post by ahaucnx »

10-1-100 wrote: post #16
bri3d wrote: post #12

Worth noting that 50-60% of passenger cars in France are diesel, but Paris have been gradually banning older higher emission diesels (Crit’air 3, 4, 5) from Paris. Banning cars outright also works, of course, but I suspect a lot of the reduction can be attributed to getting particularly bad diesel cars out vs. the limited areas where cars are entirely restricted.

Also worth noting that with modern emissions standards (and transition to EVs), over 50% of handful particulates come from tires, brakes, road surface wear, and resuspended dust: https://www.oecd.org/en/publications/non-exhaust-particulate... I don't think there's any healthy level of private cars coexisting with humans in a city, without even considering the more immediate harms from crashes, etc.

It seems that there has been fundamental mistakes and overstatements in the amount of particles from brakes in much of the secondary research in the last decades.

Details: https://pubs.acs.org/doi/10.1021/acs.estlett.4c00792

Re: Air pollution fell substantially as Paris restricted car traffic

#84

Post by aziaziazi »

stavros wrote: post #51
10-1-100 wrote: post #16

Earlier quoted context omitted.

Also worth noting that with modern emissions standards (and transition to EVs), over 50% of handful particulates come from tires, brakes, road surface wear, and resuspended dust: https://www.oecd.org/en/publications/non-exhaust-particulate... I don't think there's any healthy level of private cars coexisting with humans in a city, without even considering the more immediate harms from crashes, etc.

With EVs, 100% of particulates are from tires, etc! It's a disaster! Except, you know, the amount remained the same, we just got rid of the other 98% that used to be there.

Well IIRC ev are significantly heavier than ice in average, which has a direct consequence on amount of stress on the tires and brakes pad.

Re: Air pollution fell substantially as Paris restricted car traffic

#85

Post by beardyw »

Swizec wrote: post #32
dmckeon wrote: post #27

Earlier quoted context omitted.

Regenerative braking would tend to reduce particulates from friction braking.

Most European cars already have engine braking. EV regenerative braking just maintains the behavior that folks only used to automatics forgot about. Automatics I think are still not super common in Europe.

In the UK about one third are automatic but make up three quarters of new registrations.

Re: Air pollution fell substantially as Paris restricted car traffic

#86

Post by FredPret »

azinman2 wrote: post #22
10-1-100 wrote: post #16

Earlier quoted context omitted.

Also worth noting that with modern emissions standards (and transition to EVs), over 50% of handful particulates come from tires, brakes, road surface wear, and resuspended dust: https://www.oecd.org/en/publications/non-exhaust-particulate... I don't think there's any healthy level of private cars coexisting with humans in a city, without even considering the more immediate harms from crashes, etc.

Wonder if anyone is working on ways for breaks and tires to be less harmful, or polluting?

I wouldn’t be surprised if we make great strides in this at the rate that materials science is barrelling along

Re: Air pollution fell substantially as Paris restricted car traffic

#87

Post by eesmith »

stavros wrote: post #67
10-1-100 wrote: post #18

Earlier quoted context omitted.

With modern emissions standards, more than 50% of the harmful pollution comes from tires/brakes/road surface wear/resuspended dust: https://www.oecd.org/en/publications/non-exhaust-particulate... Moving away from privately owned cars entirely seems to be the only way to eliminate the health impact of cars on people in a city.

Are publicly-owned cars somehow not emitting anything? Or, how else will people get around? I live in a European city, where I rarely use my car to get around. Banning cars won't do anything, because I don't use my car because I can, I use it because I have to. If you want to get rid of cars, design cities that can be lived in without having to use cars.

People wouldn't use publicly-owned cars, they would used publicly-owned buses, trams, subways, and other forms of mass transit, plus (as the article points out), making it easier to walk or bike.

I believe the goal of limiting car use in Paris is as part of re-designing the city so it can be lived in without having to use cars, yes.

Re: Air pollution fell substantially as Paris restricted car traffic

#88

Post by appreciatorBus »

ethagknight wrote: post #34
10-1-100 wrote: post #16

Earlier quoted context omitted.

Also worth noting that with modern emissions standards (and transition to EVs), over 50% of handful particulates come from tires, brakes, road surface wear, and resuspended dust: https://www.oecd.org/en/publications/non-exhaust-particulate... I don't think there's any healthy level of private cars coexisting with humans in a city, without even considering the more immediate harms from crashes, etc.

I flipped through the summary of that report, and I would think there is almost surely no way this is true, unless focusing on worst case assumptions like aggressive driving styles and very poorly maintained vehicles. Your conclusion that there is not “any healthy level of private cars coexisting” is heavy handed. There is a balance, but I suspect it’s more of a jealousy/equality issue. Heavily taxed and high quality…

My desire not to inhale brake & tire particulate, not to be killed while walking to the store, and not to subsidize others expensive lifestyles, is not rooted in jealousy.

I owned a car once, it was sometimes convenient, interesting & fun, but it was also often infuriating, terrifying and expensive. If I can pull it off, I'd prefer to never own one again. I don't really care if anyone else owns them, I just don't want to subsidize them or have their externalities imposed on me.

An alternative to outright bans is to make some good faith attempt at estimating externalities and internalizing them, and reducing subsidies such as free, or below market rate public land for private vehicle operation & storage. But this is difficult and it's not clear the politics of it would be much better than an outright bans. If a good faith effort determined that operating a car while not being subsidized and not inflicting externalities on others, cost a significant amount of money, then the whole effort would be castigated as limiting driving to the very rich, and probably wouldn't go very far. So it feels like we end up with either "everyone drives everywhere all the time for everything and it's the govt's job to shovel public funds & land at it" or outright bans in popular areas.

Cars, oil, and the internal combustion engine, are all tremendously useful, and we would be foolish to pretend otherwise. But all tools have their ideal uses and all tools can be misused & overused to bad ends, both for the tool user and for others.

A world of 100% gasoline car ownership where the car was simply a fun toy for kick ass weekend road trips, and cities had never been bulldozed to make room for them as substitutes for our legs, would be a pretty great world, even if it involved a bit more pollution/externalities/subsidies than some utopian car free world.

Re: Air pollution fell substantially as Paris restricted car traffic

#89

Post by MPSFounder »

stavros wrote: post #51
10-1-100 wrote: post #16

Earlier quoted context omitted.

Also worth noting that with modern emissions standards (and transition to EVs), over 50% of handful particulates come from tires, brakes, road surface wear, and resuspended dust: https://www.oecd.org/en/publications/non-exhaust-particulate... I don't think there's any healthy level of private cars coexisting with humans in a city, without even considering the more immediate harms from crashes, etc.

With EVs, 100% of particulates are from tires, etc! It's a disaster! Except, you know, the amount remained the same, we just got rid of the other 98% that used to be there.

Just not true. I favor EVs, but it is incredibly misleading to say 98% comes from other sources. In many places, natural gas and coal are still used to generate the electricity needed. That must be accounted for in your life cycle analysis. In fact, once you remove the Musk propaganda, Tesla's EVs are by no way greener (draw a boundary around his other company SpaceX, and the rocket fuel it uses, and you immediately see what I mean. Worse than Exxon I would bet)

Re: Air pollution fell substantially as Paris restricted car traffic

#90

Post by FredPret »

trollbridge wrote: post #64
dmckeon wrote: post #27

Earlier quoted context omitted.

Regenerative braking would tend to reduce particulates from friction braking.

But spews forth more rubber (and plastic, since that's what tyres are made from these days), which is an ongoing problem for Tesla EVs when owners discover their tyres don't last nearly as long because they're transmitting power both when starting and stopping, not just when starting.

It’s because they weigh more
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