And don't think that driving a Tesla will actually reduce carbon footprint ;) Also I am not sure if CO2 is really the most problematic greenhouse gas, I think it's methane. Someone correct me if I am wrong.
I strongly suspect water vapor from con-trails. The tendency to seed cloud formation is well documented, it's a much stronger GHG than CO2, and coincidently air travel has grown right along with total fossil fuel usage. Oh, and the weather forecasters are only recently learning to get it right in the models.
What would you estimate the ratio of total water vapor from contrails is compared with the rest of the atmosphere? And if that's small, why would it be so significant?
> The tendency to seed cloud formation is well documented
Methane is definitely a more potent greenhouse gas, but it doesn't accumulate in the atmosphere for as long as CO2 does, so I wouldn't be so sure about it being more problematic.