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Reverse traffic pyramid
(mastodon.green)
A community for those who enjoy bicycling for any reason— utility, recreation, sport, or whatever!
Post your questions, experiences, knowledge, pictures, news, links, and (civil) rants.
Rules (to be added on an as-needed basis)
Welcome!

You're right, I misremembered. It's not the CO2 that has a higher effect when released at altitude than on the ground.
It's Nitrogen Oxides, water vapor and soot.
"In 1999, the IPCC estimated aviation's radiative forcing in 1992 to be 2.7 (2 to 4) times that of CO2 alone − excluding the potential effect of cirrus cloud enhancement.[6] This was updated for 2000, with aviation's radiative forcing estimated at 47.8 mW/m2, 1.9 times the effect of CO2 emissions alone, 25.3 mW/m2.[7]"
https://en.wikipedia.org/wiki/Environmental_impact_of_aviation#Factors