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Fire must surely have a role to play there? Too much O2 and plants burn easily, too little and fires won't take hold. And we don't know AFAIK that it's been en
by Earw0rm 2y ago
Fire must surely have a role to play there? Too much O2 and plants burn easily, too little and fires won't take hold.
And we don't know AFAIK that it's been entirely stable. There's some debate over what the level was in the Cretaceous for example.
- pfdietz 2y agoIf anything, fire would be a positive feedback. That's because fire produces charcoal, and charcoal doesn't decompose. Instead, it gets washed into the ocean and eventually buried. It's not photosynthesis itself that causes O2 accumulation in the atmosphere, it's the burial and sequestration of reduced material from photosynthesis.