Comment by autoexec
4 hours ago
> It’s a self-correcting system. The air and the water will recover, the earth will be renewed.
Sadly this really isn't the case, and there are a lot of things we can do that will permanently fuck the planet. It can't be certain that we will kill ourselves off before we cross some tipping point that will eventually turn the Earth into just another lifeless rock in our solar system.
We probably couldn't sterilize the earth even if the entire humanity wanted it more than anything else and threw everything it had to make it happen and then some more.
Even destroying the entire humanity would be hard, civilization could go, we have plenty of scenarios for that, but killing every human, even the odd tribe of refugees who could survive in a cave somewhere is something else. I'd say it is the maximum extent of what our technology could do. By that I mean nuking everything we could nuke, including things like volcanoes, mass produce all the greenhouse gases, the ozone depleting ones, the poisonous ones just to release them all, have our finest biologists prepare a pandemic, we may even try to bring in some asteroids.
To sterilize the Earth we would need to destroy all the extremophile bacteria, the tardigrades, the deep biosphere,... That's not happening. Note that we are very careful to sterilize Mars rovers, so that we don't contaminate Mars with Earth life. That's how hardy we consider life to be.
Well, "permanently fuck the planet" can be a matter of perspective. The great oxidation event "fucked up" the planet for anaerobic life, but we would not exist without it, so it was a huge blessing for us. Even human CO2 emissions could be viewed as a huge blessing for biosphere in the far future since it releases captured carbon ("the currency of life") thus significantly delaying the timeline of atmospheric CO2 depletion to levels at which photosynthesis becomes impossible.
That seems pretty arrogant that a hundred million years or more won’t restart life back on Earth. But I also might just be ignorant. What could we do to end all life on earth and prevent future life from forming?
Well there are some well-described scenarios of what could've happened to a hypothetical ancient life on Mars. There's some evidence suggestion methane-producing microbes may have lived on Mars 3.7 to 4.1 billion years ago that may have lead to the CO2 and hydrogen being replaced with methane, stripping away the planet's protection and leading to rapid glaciation and total extinction.
Indeed earth has itself had a few close calls with total extinction https://en.wikipedia.org/wiki/Medea_hypothesis
99.5% of life may have died during the Great Oxidation Event. 96% of all marine life may have died during the Permian–Triassic extinction event
TBH it's no short of a miracle that we're still here.
I love that word, “may.” The linchpin of so many suppositions.
Well there we go. TIL.