Your conclusion is not supported by your premise. Reversion to a mean implies convergence to a stable, unmoving equilibrium. This requires that all forces are r

Your conclusion is not supported by your premise. Reversion to a mean implies convergence to a stable, unmoving equilibrium. This requires that all forces are restoring forces in the vicinity of that equilibrium. While Earth's climate does have several restoring forces around the current equilibrium, there is one force in particular that is being relatively rapidly shifted away from the current equilibrium: the greenhouse effect. Both simulation and observation provide evidence that this force is sufficiently strong to destabilize the current climate equilibrium.