This is what my quick google turned up [1]. > A molecule of methane traps more heat than a molecule of CO2, but methane has a relatively short lifespan of 7 to

This is what my quick google turned up [1]. > A molecule of methane traps more heat than a molecule of CO2, but methane has a relatively short lifespan of 7 to 12 years in the atmosphere, while CO2 can persist for hundreds of years or more. Doesn't mean it's correct though so I'd be happy to see different thinking on this. That being said, IIRC, isn't one of the models for the increasing methane the melting permafrost [2]? So the levels are somewhat expected to be increasing pretty rapidly as a result of global warming in general. [1] https://climate.nasa.gov/vital-signs/methane/ https://climate.nasa.gov/vital-signs/methane/ [2] https://earth.org/data_visualization/what-is-permafrost/ https://earth.org/data_visualization/what-is-permafrost/