They still require things like oxygen and liquid water, neither of which will exist in appreciable amounts under a venus-like runaway greenhouse scenario. The earth, since life existed, has not ever experienced anything close to that.
It’s a scary concept to be sure. It does make me wonder, however how it wasnt triggered when the Earth was still highly geologically active with volcanoes constantly spewing the Earth’s contents into the atmosphere.
If that didn’t make it occur, what prevented it? If it did occur, then it was clearly a temporary state that Earth has some mechanism to mitigate to return to something resembling its current state on a massive enough timeframe. Interesting stuff.
The earth was still a primarily molten ball and hadn’t cooled yet. Much of the gases that contribute to the effect are trapped in permafrost and ice at the poles. There’s also, of course, the matter of all the previously trapped carbon being pulled out from underground that otherwise wouldn’t ever have a chance to reenter the atmosphere. The atmosphere of the early and geologically overactive earth was also much less dense as much of the water and gases came after that period on comets.
They still require things like oxygen and liquid water, neither of which will exist in appreciable amounts under a venus-like runaway greenhouse scenario. The earth, since life existed, has not ever experienced anything close to that.
It’s a scary concept to be sure. It does make me wonder, however how it wasnt triggered when the Earth was still highly geologically active with volcanoes constantly spewing the Earth’s contents into the atmosphere.
If that didn’t make it occur, what prevented it? If it did occur, then it was clearly a temporary state that Earth has some mechanism to mitigate to return to something resembling its current state on a massive enough timeframe. Interesting stuff.
The earth was still a primarily molten ball and hadn’t cooled yet. Much of the gases that contribute to the effect are trapped in permafrost and ice at the poles. There’s also, of course, the matter of all the previously trapped carbon being pulled out from underground that otherwise wouldn’t ever have a chance to reenter the atmosphere. The atmosphere of the early and geologically overactive earth was also much less dense as much of the water and gases came after that period on comets.