I hate noise pollution too, but out of curiosity if you live in a place where winter has the properties that makes sound travel further, doesn't it also necessarily have the properties that make it a bad idea to leave your windows open?
Upper floor apartments can sometimes get quite toasty, even with the heat turned off. There was a recent HN discussion about this but I wasn't able to find it.
Had the same thought but then thought that perhaps a smaller window upstairs opened mid-day would help airflow without affecting heat so much
How much does temperature affect sound distance? How about humidity?
When it gets cold, the leaves fall off of deciduous plants.