ormr

Would be nice to be able to pick out individual source polluters for a range of substances

We can already do that today with inverse modeling of atmospheric substance transport and the satellites you mentioned. Heard a talk about the topic on a conference 4 years ago. That's how scientists could pinpoint the emission source for some illegally emmitted CFCs in China (and afaik the Chinese govt acted accordingly). With high resolution data you can also use these methods to detect methane leaks in gas pipelines etc.

Thanks for pointing that link out. Disgusting to say the least…

Wrong. It's the talk of authoritarian extremist politicians in all countries.

We have all kinds in my city: Medieval cobblestone, brick roads and asphalt. As a cyclist I have to tell you that I hate all kinds of brick roads that I have encountered. Even when they're not the horrible middle age version, they will often get deformed by roots or depression of the ground quite rapidly, making them even more bumpy. For this reason I think, I saw in Sweden in an otherwise bricky city center that they had a narrow asphalt lane on the side of the road for cyclists. I was just amazed that someone would spend that much thought into what's great for cyclists. As a cyclist I really love asphalt :D