  The present earth warming up is often explained by the atmosphere gas
greenhouse effect. This explanation is in contradiction with the thermodynamics
second law. The warming up by greenhouse effect is quite improbable. It is
cloud reflection that gives to the earth s ground its 15 degres C mean
temperature. Since the reflection of the radiation by gases is negligible, the
role of the atmosphere greenhouse gases in the earth warming up by earth
radiation reflection loses its importance. We think that natural climatic
oscillations contribute more to earth climatic disturbances. The oscillation
that we hypothesize to exist has a long period (800 to 1000 years). The glacier
melting and regeneration cycles lead to variations in the cold region ocean
water density and thermal conductibility according to their salinity. These
variations lead one to think about a macro climate oscillating between maximum
hot and minimum cold temperatures. This oscillation is materialized by the
passages of the planet through hot, mild, and cold eras, leading to the great
season climatic oscillation phenomenon (GSCO). Thus, our planet lives four
great seasons a great spring, a great summer, a great winter and a great
autumn/fall, making a great year embracing our four small classical yearly
seasons. The probabilistic character of the parameters that are at the origin
of this climatic oscillation makes the long-term prediction less precise but
the deterministic tendencies and the resonance phenomena give precious
information on our planet climatic future. The present warming up is well
interpreted in the frame of the great season climatic oscillation theory.
