Tim WhiteThere is a survey currently running on the Doomstead Diner, which asks people to make specific, numerical estimates about the timing of human extinction. It is inspired by the work of Guy McPherson, who has amassed much scientific evidence that points to very major climate disruption occurring over the next 2-3 decades, caused by multiple runaway positive feedback effects, such as Arctic methane release. Guy's conclusion is that these changes will mean that the Earth will no longer provide a habitat for humans, leading to near-term human extinction. His reasoning, as far as I have been able to piece it together, rests on a supposition of time-invariance: the planet will be warmer than it has ever been in human experience; therefore, no humans will survive. This is far short of a proof.
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