Est-on sûr que le réchauffement récent de la planète est d’origine humaine ?

Préambule: l’historique et le contexte

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Origines de la variabilité climatique ?

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Un équilibre énergétique fragile

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« The climate is constantly changing. Alternate cycles of longcold periods and much shorter interglacial warm periods occur with some regularity. The typical length of climatic cycles in the last 2 million years was about 100,000 years, divided into 90,000 years for Ice Age periods and 10,000 years for the warm, interglacial ones. Within a given cycle, the difference in temperature between the cold and warm phases equals 3°C to 7°C. The present warm phase is probably drawingto an end—the average duration of such a phase has already been exceeded by 500 years.

Code radiatif: Effet de serre total 155 W.m2 : effet nuages+vapeur d’eau 66-85% et CO2 9-26%. Naïvement, la contribution du CO2 est donc entre 3 et 9 deg.C

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Les faits et arguments

Le soleil acteur principal du système climatique ??

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Le destin de Zbigniew …