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Comment by philshem | Hacker News Reader

Here's a related, recent New Yorker article about the melting permafrost.

https://www.newyorker.com/magazine/2022/01/17/the-great-sibe...

> Over thousands of years, the frozen earth swallowed up all manner of organic material, from tree stumps to woolly mammoths. As the permafrost thaws, microbes in the soil awaken and begin to feast on the defrosting biomass. It’s a funky, organic process, akin to unplugging your freezer and leaving the door open, only to return a day later to see that the chicken breasts in the back have begun to rot. In the case of permafrost, this microbial digestion releases a constant belch of carbon dioxide and methane. Scientific models suggest that the permafrost contains one and a half trillion tons of carbon, twice as much as is currently held in Earth’s atmosphere.

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But doesn't the article suggest that the recent rapid rise comes from methane produced by microbes? If this is true, it is not the melting permafrost, but (intensive) agriculture that is the culprit.

> But since 2007, when methane levels began to rise more rapidly again, the proportion of methane containing 13C began to fall (see ‘The rise and fall of methane’). Some researchers believe that this suggests that much of the increase in the past 15 years might be due to bacterial sources, rather than the extraction of fossil fuels.

Isn't the methane in permafrost produced by microbes? It's basically wet lands that ended up being frozen, and as they thaw they go back to releasing the methane being processed by the breakdown of organic matter from microbes.

Not necessarily, it also comes from natural gas: https://www.pnas.org/content/118/32/e2107632118#:~:text=Meth....

So then what happens, the microbes eat stuff, more soil is produced, more trees and animals grow, more rain comes, more stuff gets buried, and the cycle repeats itself?

Honest question, not refuting anything here just a lot of the articles stop at the melting part, what happens after that?

It's more like microbes eat stuff -> greenhouse gases released -> climate warms -> more permafrost melts -> microbes eat more stuff -> feedback loop which eventually melts all the permafrost and triples the atmospheric carbon -> cataclysmic and permanent disruption of global weather patterns. It's not a cycle, it's a one-way phase transition.

The problem is that which microbes do the job depends on how much oxygen is available. If there's not enough, like when buried, the decomposition is anerobic. This produces a lot more methane than aerobic decomposition.

It’s a problem for people alive today, but the earth will just rinse wash repeat no ?

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