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Comment by xen2xen1 | Hacker News Reader

I'm not quite sure, does burning it make it less harmful?

In general CO2 is a far less potent greenhouse gas than CH4, largely because there is already a permanent low level of carbon dioxide in the atmosphere. In a few decades the methane will oxidize to CO2, but in the meantime it’s like 40 times more potent. Better to burn it.

(Not sure if CH4 is inherently stronger than CO2 because of more possible quantum states, but I suspect atmospheric abundance is the main factor (without looking it up))

My layperson understanding was that the more atoms/bonds a molecule has, the less transparent it was to IR. Diatomic molucules like oxygen and nitrogen were pretty much transparent, molecules like CO2 and H2O were in the middle, and bigger ones like CH4 were less so.

I have a hazy understanding from the atmospheric radiation course I took a decade back, but if I recall correctly the vibrational states of a two-atom molecule are simply not at affected by infrared. To be a greenhouse gas, you need the, uh, rotational states provided by three or more atoms. Or something like that? I was always more of a dynamicist and barely scaped by in atm chem (it’s almost all free radical chemistry). Anyway you definitely need a third atom.

Yes, burning methane converts it to CO2, which is much less harmful of a greenhouse gas

https://www.bbc.com/news/science-environment-63083634

It looks like cancer and leukaemia for surrounding populations too, so capping or capture protocols may not kick the can as far.

Not an expert but quickly googling: Methane is 84x more contributing to the warming than CO2 over the first 20 years, per kg emitted.

It persists in atmosphere shorter than CO2 though, so a 100 year coefficient is 28x.

Source: https://climatechangeconnection.org/emissions/co2-equivalent...

Any other use of methane besides combustion most likely ends up releasing the exact same amount of energy as burning it.

For instance, nitrogen fertilizer eventually breaks the hydrogen bonds and ends up back in the atmosphere.

Burning it at the source means thatuch more gas will also be extracted and (ultimately) burnt for the other use.

2xNH3 -> 3xH2 + N2 is fine, only excepting that more NH3 will need to be made. In the future it will be made with wind or solar energy, but that is still a few decades off.

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