The condensation nuclei are formed by some leave hygroscopic that they are originated from the water of the sea, beyond some gases as hygroscopic oxides of sulphur and match that are produced by intermediary of the industrial production or the combustion of gases in centers highly urbanizados. It fits to stand out, that nor all the originated oxides of the industrial process and nor so little the common toxic dust in great centers with high intensity of vehicles go to generate condensation nuclei. The formation of hygroscopically active nuclei of condensation occurs when, according to Tubelis (1980, p.167) ‘ ‘ the relative humidity of air reaches one definitive value, that in some cases can be so low how much 70%’ ‘. Soon, (Ibid, p.168) ‘ ‘ when become assets, the nuclei start to adsorver vapor molecules d? water, increasing of size and reducing the visibility, giving origin to a mist mida’ ‘. The existence of hygroscopic particles in suspension in the atmosphere are an essential condition for the cloud formation, that beyond this element needs great amount of vapor d directly? water in suspension in the atmosphere, that later will go to cool itself from the moment that suffers adiabtica expansion. These, therefore, are the necessary elements for the formation of a cloud, that can have origin through the thermal convection for adiabtica expansion, or for intermediary of the rise of the relief, as well as, of the shock between front of air mass de with distinct thermal characteristics and humidity. The rocking of solar radiation of the Land is related the factors that influence directly in the interaction of the solar ray with the terrestrial surface, such factors is the surface distribution eliminates and continental as well as the aspects of the same ones, the period of the day, the period of the year, the latitude, at last, in the terrestrial surface meets distributed zones of thermal behavior with distinct, resultant characteristics however of positive rockings of energy as in the tropical zones, or of negative rockings of radiation as in the polar zones.