David Appell: "if humans are really so stupid as to not take some drastic action by at least 2050, when total warming would be 3.0°C -- if even after that we continue to burn fossil fuels at an ever-increasing rate, well then we are clearly too stupid to deserve to continue as a species, and the Universe would best be rid of us"

Quark Soup by David Appell: Reuters: Correction on 11 F by 2050

...if humans are really so stupid as to not take some drastic action by at least 2050, when total warming would be 3.0°C -- if even after that we continue to burn fossil fuels at an ever-increasing rate, well then we are clearly too stupid to deserve to continue as a species, and the Universe would best be rid of us.

(Unfortunately we would take a lot of other species down with us. (I don't suppose "we're sorry" would help much?) But some species will survive -- extremophiles, if no one else -- and they'd get a chance to start over.)