Global temperature increases may be irreversible by conventional means. The best solution is to encourage Ragnarok, the End of the World.
Per Norse Mythology, Ragnarok is preceded by Fimbulwinter, a period of three winters with no intervening summers during which snow shall come from all directions. Yes, brother will kill brother, but average global temperatures should drop by thirty degrees.
Invoking these events will require winding the Gjallarhorn, causing the world-tree to shudder, and spawning tsunamis by awakening the Midgard Serpent. There will be wars, deluges, and Gods will regrettably die, but the environmental benefits more than outweigh these downsides.
Per Norse Mythology, Ragnarok is preceded by Fimbulwinter, a period of three winters with no intervening summers during which snow shall come from all directions. Yes, brother will kill brother, but average global temperatures should drop by thirty degrees.
Invoking these events will require winding the Gjallarhorn, causing the world-tree to shudder, and spawning tsunamis by awakening the Midgard Serpent. There will be wars, deluges, and Gods will regrettably die, but the environmental benefits more than outweigh these downsides.