alt Hacker NewsIf only you could see it. In the big cities the air quality has improved, however, I am not sure if it really has, or if we are now just burning hydrocarbons more efficiently so that the particle sizes have become invisible.
Put it this way, although cars are allegedly better than they were, fuel consumption hasn't dropped considerably. The cars are more numerous than ever, and, although there are EVs, there are still more ICE cars than there were in the good old days when petrol came with lead in it.
I am not sure that most people in urban areas even know what good air tastes and smells like. I take a canal path through lush countryside, far from any cars for most of the way. This canal has an aqueduct (or is it a viaduct?) over a motorway and the contrast is incredible. You go from basically smelling flowers to air pollution and back to clean air again quite quickly, so the filth is totally noticeable. Note the cars on the motorway are going at speed, so they should be working efficiently (until a few decades ago 56 mph was what engines were optimised for regarding efficiency in the UK).
If just living in a major city then you don't get this instant switch from bad to good air. So you just don't notice it. If you could see the filth, you would prefer a swimming pool that was pissed in, it is that toxic.
If you do have to live in a city, my top tip is to find out if there are any meteorologists in town. If there are, buy a house next to where they are living. Anecdotal, however, I used to work with meteorologists and they would always live to the West of the city centre, to get cleaner air than those living in the east of the city, or further downwind.
Again anecdotal, however, due to the canal and motorway experience described above, in post-industrial countries such as the UK, it is definitely the vehicles rather than any other source. Given the choice of microparticles that just get in your blood or clumps of big particles that you can eventually cough up and spit out, I would much prefer the latter. My hunch is that the legislation to improve vehicle emissions has optimised the exhaust for nanoparticles. Please prove me wrong!
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For urban areas the risk of air pollution is another reason for cities to have congestion pricing to support public transportation.
> I am not sure that most people in urban areas even know what good air tastes and smells like.
I run air filters in my apartment throughout winter months, which tend to be the worst in terms of air quality here.
When I go outside in the morning I can really smell the stuff in the air, for a brief moment, until I get used to it. But you definitely notice the difference!
Exhaust fumes were easy to optimize.
Lots of particles cars emit are from tires and break pads. I think someone was measuring that but I don’t have sources but most likely I read that somewhere in the comments of HN.
> Anecdotal, however, I used to work with meteorologists and they would always live to the West of the city centre, to get cleaner air than those living in the east of the city, or further downwind.
The industrial-revolution era mill owners were very aware of this too. Posh area of Manchester is to the south (westerly winds;) Leeds to the north (mix of northerly and westerly winds I believe).
Also, anecdotally, smaller towns and villages can have poor air quality too due to log burners. They're an absolute pain. You can tell when an area has become gentrified when shiny new chimneys start popping up or a log burner shop opens up!
Sure thing, here's a report from the Greater London Authority tracking the history of air quality in the city since the "Great Smog" event 1952, which caused an estimated 4000 deaths.
https://www.london.gov.uk/programmes-strategies/environment-...
The main takeaway is that yes, urban air quality (including fine particulate matter) has improved massively over time, but most of it had little to do with road traffic, as for decades it wasn't a significant contributor to the overall mix. The important change was the move away from burning solid fuels like coal for household heating and in power stations within cities, to using gas and electricity with larger, out-of-town power stations.
As other sources have declined, road traffic has indeed become the largest contribution to urban air pollution, but even here there has been progress. Fine particulate emissions have continued to decline as car manufacturers have adapted to more stringent regulation (cheating scandals notwithstanding). A bigger problem now is higher non-exhaust emissions caused by larger and heavier vehicles. This is something else that will need to be solved via regulation. Other policies like Low Traffic Neighbourhoods can also help to restrict the worst pollution to major roads and away from where most people live.
Urban air quality is never going to be as good as that in the countryside, but it's not true to believe that no progress has been made, and that it's simply been a switch in the type of pollution.