Circumstellar Habitable Zones to Ecodynamic Domains: A Preliminary Review and Suggested Future Directions · HackerPapers discussions

Circumstellar Habitable Zones to Ecodynamic Domains: A Preliminary Review and Suggested Future Directions — mentioned by apo

Wed, 18 Jul 2018 21:34:37 GMT

Photosynthesis produces oxygen at a rate faster than the rate of depletion due to oxidation of the Earth's crust (think rust). Without plants there's nothing left to spew oxygen back into the atmosphere. Photosynthesis converts CO2 into carbohydrates. Lowering the concentration of atmospheric CO2 slows this reaction. Plants also metabolize carbohydrates, producing CO2. So photosynthesis requires the right balance of CO2 concentration and light. The estimate for when CO2 levels would fall too low appears to come from the following linked article: The latter authors feared that photosynthetic…

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Circumstellar Habitable Zones to Ecodynamic Domains: A Preliminary Review and Suggested Future Directions — mentioned by philipkglass

Wed, 18 Jul 2018 21:05:41 GMT

I couldn't find the 800 million year figure specifically in the cited source: https://arxiv.org/pdf/0912.2482.pdf The general idea, I believe, is that the carbonate-silicate cycle will shift more toward carbonates over time. The Earth will warm substantially as the sun's luminosity increases over millions of years. Warmer conditions will accelerate the reaction of water and carbon dioxide with silicate minerals like magnesium and calcium silicates, shifting the equilibrium to favor more carbon-as-insoluble-carbonate and less carbon-as-available-CO2. Plant life will eventually go extinct from…

Paper and discussion history. A mention is not an endorsement.