Every tonne of carbon emitted imposes $3000 in costs? That must mean that every ton of carbon emitted also provides at least $3000 in benefits, because humanity

Every tonne of carbon emitted imposes $3000 in costs? That must mean that every ton of carbon emitted also provides at least $3000 in benefits, because humanity is a lot richer on net since we began blasting the stuff into our atmosphere a few hundred years ago. Or, their calculation is off. Could be either one.