Hmm. Assuming I’m on board with apocalypse, this kinda seems like a hat on a hat. Couldn’t we destroy the magnetosphere and vent the atmosphere with less energy than it would take to get all that carbon out? Or, hell, deorbit the moon one more time? I guess it’s harder to ramp up that tech in secret/with a benign excuse.
Plus a lot of it’s in living beings — you’d either have to find and harvest/burn all of them manually (or wait for the decomposition cycle to get it in the air I suppose?). At that point, you might as well go with a classic Skynet-style small-arms-based doomsday!
Couldn’t we destroy the magnetosphere and vent the atmosphere with less energy than it would take to get all that carbon out? Or, hell, deorbit the moon one more time?
I think that both of these require far more energy than keeping carbon locked out of terrestrial circulation (and hence out of living things). Don't you have to destroy the Earth's iron core to destroy the magnetosphere? You barely have to scratch the Earth's crust in my scheme. Of course my scheme requires much more time to work, so it's not very flashy.
This idea came to me while considering that most science fictional planet-sterilizing weapons use imaginary physics (The Three Body Problem, Revelation Space, the Xeelee Sequence, The Forge of God...) or, at the very least, a stellar-scale expenditure of energy (The Killing Star). What's the most energy-efficient approach that is compatible with known physics?
Total carbon sequestration doesn't work against a prepared adversary with near-peer technology, but it works great as an alien device for quietly exterminating life from selected planets. The thing is like an invasive species made of silicon that no carbon-based life can compete or coexist with.
Plus a lot of it’s in living beings — you’d either have to find and harvest/burn all of them manually (or wait for the decomposition cycle to get it in the air I suppose?). At that point, you might as well go with a classic Skynet-style small-arms-based doomsday!