Why is Methane Such a Strong Greenhouse Gas?

What are the actual mechanisms that make ch4 so much more effective than co2 as a greenhouse gas. I have looked at things like the frequencies they adsorb and emit as well as the specific heat of these molecules. Neither seem to account for the large difference in effectiveness. I speculate that sometimes ch4 passes energy kinetically to other molecules before it has the chance to re-emit, thus slowing radiative heat transfer to outer space. Are there other factors involved, and if so what are they? Thanks
- justin ferguson (age 58)
stillwater ok usa

The big difference is that the methane absorption lands in a window in the infrared where there's not too much other absorption. There's already so much CO₂ that adding any more mainly just boosts the wings of its absorption lines.

Here's a nice picture of the important absorption spectra:

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Mike W.

(published on 10/14/2015)