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Scientists unveil methane munching monster, 100 million times faster than nature
(interestingengineering.com)
This is a most excellent place for technology news and articles.
It's complicated. The breakdown of methane in the atmosphere depends on hydroxyl radicals that are created at a regular rate. If you have more and more methane released, and/or you have other chemicals that also react with those radicals, the overall average half life will increase. Both those things are happening, so the old half life really isn't as accurate as it used to be. Guess which number the IPCC still uses for its models though.
Goddam Hydroxl Radicals keep sending drones to attack US ships! Iran needs an ass-kicking!