This paper [0] suggests improvements in car emissions has played a big role in reducing emissions in European cities as a whole. Vehicle emissions of all kinds have fallen pretty dramatically across Europe [1], although this is total emissions for vehicles, so it includes policies to reduce driving as well as those to reduce each vehicle’s emissions. So overall trends toward more efficient cars are certainly part of the story. Given these images are between 2007, when emissions had already been falling, and 2024, I’m inclined to think the policies highlighted in the article played a significant role as well.

[0]: https://www.sciencedirect.com/science/article/pii/S259016211...

[1]: https://www.eea.europa.eu/en/analysis/indicators/emissions-o...

Given that tires produce a lot of particulate matter, even EV's contribute to pollution significantly.

Wouldn’t that mean bicycles contribute to air pollution?

It's proportional to weight, so I imagine bicycles are negligible.

I would imagine there is more wear and tear on a bike tire because of rough handling.

Yes, but so do humans walking. The proportions matter.

Yes cars are bikes

By a miniscule amount - probably less pollution than that produced by people walking.

Like another commenter in this thread I suspect it's mostly due to banning cars with Crit'air > 2.

No, it’s not just that. There’s a reduction in traffic. Traffic is the biggest cause of pollution. Even if the exhaust is “ clean “ (it’s not) there’s also tire dust and brake dust

I‘m currently visiting Paris for the second time in my life after 2008. I can tell you it’s much cleaner now than it has been back then. There are many electric (cargo) bikes, scooters, cars and buses. The city is much quieter and there is way less crazy traffic. There are few cars parked on the side of the street. However these parking spots were cleared for bike lanes and bike sharing parking. Biggest polluter are the garage trucks, which are still diesel and noisy. If they manage to replace them by electric ones, many parts of the city will be really quiet.

More electric cars and busses does not mean "au revoir to cars".

Sure there are cars.

In my ( very personal, more than 20 years living here ) experience, it’s a completely different city, and there definitely are fewer cars than before.

Now if car exhausts are better and both effects compound I won’t complain !