Well we are all swimming in each other’s exhausts. This is not being negative or purist, this is the reality. Local pollution is now global pollution because we are collectively so numerous and so powerful.
https://www.ncei.noaa.gov/news/arctic-ice-study
We know more than enough to begin removing GHGs from the atmosphere with technologies that disperse hydroxyl radicals like ReductionTech.com.
Governments have to make the big moves on this as soon as possible; it will not work any other way.