What if we took every polluting source on Earth, and combined them into one huge chimney? What would it look like? I'm talking all cars, trucks, buses, ships, planes, power plants, residential chimneys, steel mills, paper mills, pulp, everything. If everything that pollutes the air was combined into a single source, what would it look like?

How big would the chimney need to be to maintain a reasonable flow and pressure? Hundreds of meters wide? Kilometers? What kind of flow are we talking about?

Sorry about kinda retarded topic, but I have had this thought in my head for decades. I'm not meaning to make any arguments for or against climate change, but this has been an idea of mine to maybe visualize the total scope of humanity's effect on the atmosphere. Seeing a few tailpipes spewing smoke is not alarming, but when you think about it they're all feeding into the same environment.

Thanks for any meaningful answers, even "that doesn't make any sense"!