I rechecked, I will revise it, there are some huge variables and nobody can really agree. It would likely be anywhere between thousands to hundreds of thousands of years, but I have seen some people confidently state that if we’re not running industry and most sea life dies rapidly that it could potentially be millions of years but the carbon/oxygen cycle is wildly complicated so it’s still a pretty hard idea to calculate.
I rechecked, I will revise it, there are some huge variables and nobody can really agree. It would likely be anywhere between thousands to hundreds of thousands of years, but I have seen some people confidently state that if we’re not running industry and most sea life dies rapidly that it could potentially be millions of years but the carbon/oxygen cycle is wildly complicated so it’s still a pretty hard idea to calculate.
This exchange talks a lot about how different variables can wildly swing the results. https://biology.stackexchange.com/questions/46125/how-long-could-earths-oxygen-supply-last-if-no-new-oxygen-were-produced