One of the main authors at Curbside Classic has been posting selections of car-related pics from various cities, with a theme for each post. His latest is Detroit, the Motor City. I made an irrelevant car-related comment there, but the most interesting thing about these pics is outside of cars and houses.
The skies are clear in all of the Detroit pics from 1940s to 1970s. Several other big cities were hugely polluted in those years, and it showed in every picture. LA and Pittsburgh were always smogged up.
The difference must be geographical. LA catches fog from the ocean and traps it in front of the Sierras. Pittsburgh is a bowl surrounded by Appalachian ridges. Michigan is flat, and the prevailing wind is from the SW. Fresh air from the large flat farmland of Indiana and Ohio is always blowing into Detroit and then exiting over the lakes, with no blockage.
Spokane is similar to LA. Wind and storms from the west pile up against the mountain range in Idaho. When fog is available it sticks here. When rain is available it lingers here. When wildfire smoke is available it sticks here.
Smart city planners ought to be thinking about geography. Avoiding floods is easy. Just don’t build where a river wants to flow. Avoiding pollution follows the same principle. Don’t build where storms and pollution will pile up.
Polistra's Mill 