Résumé
Climate changes predicted by the International Panel on Climate Change are currently linked to the growth of an excess of carbon dioxide in the atmosphere, as successive reports have asserted. The forecasts are based on an unusual exploitation of the greenhouse phenomenon that results in ocean warming due to radiative forcing. In the absence of experimental support, the mechanism and the predictions are universally adopted but only by consensus. Some scientists oppose the consensus because many fundamentals of hard sciences are not respected. Therefore, we have recently proposed an alternative mechanism in which the radiative forcing due to carbon dioxide is replaced by heat, a fundamental phenomenon in physics. According to this new mechanism briefly recalled herein, heat is managed by water and its interphases equilibria, water vapor being the main obstacle to radiative elimination. Previously developed for the present times, this original mechanism is used here to show that the Earth's heat balance, hitherto said to be balanced in terms of radiative flux inputs and outputs by climatologists, has never been balanced in terms of heat. The thermal imbalance in the distant past was estimated from the energy necessary to melt the ice during the last deglaciation, the current Holocene interglacial plateau, and the 1994-2017 recent period. The melting progressed almost linearly during the first 80% of the deglaciation process, with a slow decline up to a near-steady-state during the still under way Holocene interglacial plateau. Estimates of ice loss over the period 1994-2017 suggests that the imbalance is increasing again, a feature that should lead to more evaporation and thus a proliferation of clouds masking more and more the Sun heating. This masking should lead to an inversion of the imbalance required to initiate the unavoidable next ice age. The relationship between heat imbalance and climate changes could renew the interest of applications like hydrogen and planes currently penalized due to the production of carbon dioxide. In any case, it is the fight against anthropogenic heat sources that should be promoted in the future on the basis of life cycle assessments.