After reading this question, I started wondering if we could maintain the current oxygen level of our planet with giant electrolysis factories, if all plant life were to suddenly disappear, considering our current technological level.


  • Can we supply enough energy to counter oxygen loss?
  • How would we store excess hydrogen from the process?
  • How long would our oceans last if we kept using water up?
  • Are there other things that would prevent this "solution"?
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    $\begingroup$ You mean, assuming we magically don't die of starvation first? $\endgroup$ – PatJ Nov 22 '17 at 16:37
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    $\begingroup$ We wouldn't need to, for practical purposes. It would take thousands of years for animal life and geological processes to use up all the oxygen, and we'd starve to death long before oxygen became an issue. $\endgroup$ – Mike Scott Nov 22 '17 at 16:38
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    $\begingroup$ You mean, having our current tech level but otherwise no limits in how we cooperate and how long it takes? Or you mean plants disappear, like, 28 minutes ago (when this question was posted), and humanity as we have it needs to deal with it? By the way, what about broken carbon cycle? Out of scope of this question, but you should keep it in mind. Last but not least, please limit yourself to one question per question. $\endgroup$ – Mołot Nov 22 '17 at 17:01
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    $\begingroup$ Plants aren't even that big of a contributor to oxygen. A lot of plants are oxygen neutral or even consume oxygen. The oxygen affect of losing all plants would be minimal. Also you don't want to convert water to oxygen if you were force to make it, that would make it a 1 way street. The oxygen generation needs to remove the CO2 from the atmosphere that animals produce. $\endgroup$ – A. C. A. C. Nov 22 '17 at 17:09
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    $\begingroup$ @walrus: In this scenario everybody would starve to death much before a significant dent is done in current Oxygen levels. If all photosynthetic organisms would suddenly disappear we have a few months of food left. Plants and phytoplankton are at the bottom of the food chain. Without that nothing lives for long (months at most). $\endgroup$ – ZioByte Nov 22 '17 at 18:43