Honestly, aggressive expansion of remote sensing is the only realistic way for humanity to coordinate on climate at all. There are too many opportunities to defect in the prisoner's dilemma otherwise.

Good idea! I looked into this when I first started thinking about the problem. MethaneSAT is launching this year, so I thought maybe we could do the same for refrigerants. Unfortunately I don't think it would work:

1. Methane is 1900 ppb in the atmosphere[1], refrigerants overall are ~12.5 ppb -- so a lot less out there to detect. 2. I think methane leaks tend to be from single, continuing, large point sources -- coal mines, oil wells -- whereas refrigerants are usually from these distributed small point sources which happen once. So by the time you detect it it's too late to intervene.

[1] https://www.noaa.gov/news-release/increase-in-atmospheric-me...