• Rhaedas@fedia.io
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    7 days ago

    Not quite correct on methane’s half life. The 28x number is based on normal effect and breakdown over a century’s time. Over 20 years it’s around 84x more than CO2. Over the first few years it can be far over 100x. The caveat of using these numbers now is that they were based on a stable cycle of methane and its fixed-rate reducers in the atmosphere, something that has obviously changed.

    The IPCC still sticks to the 28x number though, because it looks better on the spreadsheets. When they even include methane feedback loops, which to my knowledge they still haven’t really worked into the hard numbers. Why? Because we’re not very sure on how much is being released from year to year, as it’s hard to measure. So since the IPCC only works with known variables, they just leave it out of the equation. Makes sense, right? :clown face:

    You’re right on the rest though. The best result is the methane breaks down quickly, into more CO2 and water vapor. Both GHGs, and the additional water adding to the water content in the atmosphere. Yet another feedback loop.