Climate change has occurred, whether due to human activity or not, throughout the history of the Earth to a greater or lesser traumatic degree. We must use our great technological capacity to prevent its effects so as not to allow the change to lead to a catastrophe. The real problem derives from a social and consumeristic model which, given the current energy resources, can not be made sustainable for the world population. Demographic control, hand in hand with research into and the use of new energy models are absolutely necessary if we are to avoid a final catastrophe.