[mtdjed]

I recall my first trips to LA of seeing a yellow haze in the air called smog. Was also evident elsewhere. This is mostly gone now due to clean air efforts which is good for our lungs.
However, I have read in a copy of National Geographic that the cleaner air allows more sunlight to reach the earth and water which helps to raise the global temperature.

Did not see any mention of how much raise in temperature, but as discussions of global warming continue, it would seem that this impact should be acknowledged. Still caused by humankind even if reversing a previous negative impact.