8 ms·

I remember flying into Denver in the winter and seeing the inversion of just awful brown haze. I cried for my lungs on that trip.

sundvor 5y ago
There are numerous studies on the myriad bad health effects of PM2.5. The sooner we can transition to EVs, the better.
- throwawaylinux 5y ago
  What's the PM2.5 contribution of automobile exhaust in a city like Denver, 5-10%ish?
  - tricolon 5y ago
    I haven't found exact data for the contribution of ICE vehicles to PM 2.5 levels in Denver, but I've found some evidence of ozone [0] and carbon dioxide [1] contributions in Denver being around 30%, as well as contribution to PM 2.5 in "developed countries" being 25–30% [2]. Later edit: this EPA paper from 25 years ago [3] says "Vehicle exhaust was the largest PM 2.5 carbon contributor, constituting ~85% of PM 2.5 carbon at sites in the Denver metropolitan area". [0] https://www.bizjournals.com/denver/news/2017/10/30/here-are-the-biggest-contributors-to-denver-area.html https://www.bizjournals.com/denver/news/2017/10/30/here-are-... [1] https://www.denverpost.com/2020/01/19/colorado-air-pollution/ https://www.denverpost.com/2020/01/19/colorado-air-pollution... [2] https://publications.iarc.fr/_publications/media/download/3700/f73ec515ebe6377bd0cfe1430065193a106e7b00.pdf https://publications.iarc.fr/_publications/media/download/37... [3] https://www.epa.gov/sites/default/files/2020-10/documents/nfraqsexecsum.pdf https://www.epa.gov/sites/default/files/2020-10/documents/nf...
    - 7952 5y ago
      Also, the location of the pollution matters. The same pollutant can cause more problems released at ground level than from a stack.
      - sundvor 5y ago
        Yes, I researched this for evaluating my son's previous school - there's a sharp drop off even from the 10-20-30 metre range to the 100-150 metre one, and things like wind directions certainly matter. AusGov in their infinite wisdom built this primary school right on top of one of the busiest Melbourne streets for east-west through traffic, with long periods of bumper-to-bumper including the heavy trucks which are the worst. (You'd think cars in Aus have bad standards, but then there's the trucks.) I'm willing to bet no-one even cared, as evidenced by the complete lack of air purifiers in the classrooms.
  - afarrell 5y ago
    I wonder how much brake pads dust also contributes to PM2.5 and how much regenerative braking will decrease that effect.
garren 5y ago
Yeah, the smell that comes with it in the fall and winter is something else. I like Denver, but the brown cloud is no fun. It’s a downer coming out of the hills on I70 into the city and seeing it hanging there.
ineptech 5y ago
I gather it's better now, but flying in to LA in the 90s was similar. It felt like visiting God's ashtray.

sundvor 5y ago

There are numerous studies on the myriad bad health effects of PM2.5. The sooner we can transition to EVs, the better.

throwawaylinux 5y ago
What's the PM2.5 contribution of automobile exhaust in a city like Denver, 5-10%ish?
- tricolon 5y ago
  I haven't found exact data for the contribution of ICE vehicles to PM 2.5 levels in Denver, but I've found some evidence of ozone [0] and carbon dioxide [1] contributions in Denver being around 30%, as well as contribution to PM 2.5 in "developed countries" being 25–30% [2]. Later edit: this EPA paper from 25 years ago [3] says "Vehicle exhaust was the largest PM 2.5 carbon contributor, constituting ~85% of PM 2.5 carbon at sites in the Denver metropolitan area". [0] https://www.bizjournals.com/denver/news/2017/10/30/here-are-the-biggest-contributors-to-denver-area.html https://www.bizjournals.com/denver/news/2017/10/30/here-are-... [1] https://www.denverpost.com/2020/01/19/colorado-air-pollution/ https://www.denverpost.com/2020/01/19/colorado-air-pollution... [2] https://publications.iarc.fr/_publications/media/download/3700/f73ec515ebe6377bd0cfe1430065193a106e7b00.pdf https://publications.iarc.fr/_publications/media/download/37... [3] https://www.epa.gov/sites/default/files/2020-10/documents/nfraqsexecsum.pdf https://www.epa.gov/sites/default/files/2020-10/documents/nf...
  - 7952 5y ago
    Also, the location of the pollution matters. The same pollutant can cause more problems released at ground level than from a stack.
    - sundvor 5y ago
      Yes, I researched this for evaluating my son's previous school - there's a sharp drop off even from the 10-20-30 metre range to the 100-150 metre one, and things like wind directions certainly matter. AusGov in their infinite wisdom built this primary school right on top of one of the busiest Melbourne streets for east-west through traffic, with long periods of bumper-to-bumper including the heavy trucks which are the worst. (You'd think cars in Aus have bad standards, but then there's the trucks.) I'm willing to bet no-one even cared, as evidenced by the complete lack of air purifiers in the classrooms.
- afarrell 5y ago
  I wonder how much brake pads dust also contributes to PM2.5 and how much regenerative braking will decrease that effect.

garren 5y ago

Yeah, the smell that comes with it in the fall and winter is something else. I like Denver, but the brown cloud is no fun. It’s a downer coming out of the hills on I70 into the city and seeing it hanging there.

ineptech 5y ago

I gather it's better now, but flying in to LA in the 90s was similar. It felt like visiting God's ashtray.