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This is something I've always wondered (being someone who is heavily into compost), since the byproduct of aerobic decomposition is CO2, which is actually worse? Aerobic, or Anaerobic? Both produce GHGs, Methane is the worse one, but obviously if it was produced in smaller quantities then it would be more beneficial. Also what lasts longer in the atmosphere? CO2 or Methane?

Methane is a far more potent greenhouse gas, and it naturally degrades into CO2 in the atmosphere. Burning methane it on the ground, even not for energy, helps mitigate the warming effect, because it is that much more potent than CO2.

I get that it's more potent, i wrote that in my comment. But if composting aerobically releases 50 times more CO2 than composting anaerobically does methane, then composting anaerobically is the better option.

The CO2 from compost came from surface organic matter, which got it from the air in the first place. It is a net zero proposition (discounting potential transit costs which may or may not apply).

The rising CO2 levels in the atmosphere come from burning hydrocarbons which originate from below the earth's surface, where they were not part of the carbon cycle for millions of years. Burning faster than natural sequestration below the surface is reaponsible for the overall rise.

All else being equal, methane has a stronger greenhouse effect, but breaks down, unlike CO2 which is only sequestered by plants.

I get that it's net zero, but it's still releasing it back into the atmosphere. Burying the compostable material might actually be a way of sequestering carbon.

It is, technically, but with caveats. It has to be buried deeply enough that any gasses created by decomposition won't be released or escape on their own.

More worrisome is that, done at a scale that would matter to the atmosphere, it would have to be buried in containers that are impermeable to water forever, lest all of our underground aquifers become contaminated by bacteria and heavy metals that are naturally occurring in plants.

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