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Early Plants May Have Caused Massive Glaciation

Posted by Unknown on from the plot-to-destroy-animals-failed dept.

sciencehabit writes with this excerpt from Science: "The first plants to colonize land didn't merely supply a dash of green to a drab landscape. They dramatically accelerated the natural breakdown of exposed rocks, according to a new study, drawing so much planet-warming carbon dioxide (CO2) from the atmosphere that they sent Earth's climate spiraling into a major ice age."

1 of 174 comments (clear)

  1. Peter Wards "Medea hypothesis" by peter303 · · Score: 5, Interesting

    The Medea hypothesis is the mirror of the Gaia hypotheis. Gaia says life is in ecological balance and self-balancing.

    Part 1 of the Medea hypothesis says that life isnt necessarily in ecological balance and sometimes overruns resources nearly killing itself off. Several past mass extinctions, particularly the Permian may have been caused by this.

    Part 2 says the ultimate end of life on Earth may be running out of CO2. CO2 has been falling from tens of percent on the early Earth to about one percent in the Phanerozoic to .025% now. (Human activity has temporarily raised it to .04%.) When CO2 falls below .01% then plants cannot survive and neither animals. Just bacteria. This is predicted in few hundred million years. Life consumes CO2 and buries in hydrocarbons and limestone. Unless some imbalance like humans come along, the trend is to pretty much lock up carbon for good.

    Geo-engineering CO2 increase is straight forward. Burn limestone to release CO2. There is 100x more carbon in limestone than hydrocarbons.