The eruption of a big enough volcano can alter the climate for a period of time. It has been done. The impact of a big enough meteorite can alter the climate for a period of time. We are told that has taken place, too. Man has never changed the climate. Sure, he can poison the air, the ground, and the sea, but never has man changed the climate. Even atomic blasts have failed to do so. I guess we shall have to just keep trying. As for carbon taxes and the like, you would be better served sacrificing a goat. In that way, while accomplishing nothing, only the goat pays the price for such nonsense.