formation des nuages

CONT: Notions sur la formation des nuages. S'il est suffisamment refroidi, l'air chargé de vapeur d'eau devient saturé; un refroidissement plus poussé peut en provoquer la condensation sur des corpuscules d'impuretés en suspension dans l'atmosphère (noyaux de condensation), entraînant ainsi la formation des gouttelettes d'eau qui constituent les nuages.
OBS: Ne pas confondre la «formation des nuages» avec la «formation nuageuse», deux notions qui incidemment se rendent par le même terme en anglais «cloud formation».

CONT: All clouds, from the puffy cumulus to the wispy cirrus, is a portion of air that has condensed into visible moisture. Cooling of such a portion of air to its dew point is by far the main reason for cloud formation. The main cause for the cooling lies in some process which causes air to rise or be forced upward. Large warm air masses may slide up the slope of a colder heavier mass of air. As the warmer air overrides the cooler, the warm air expands and is cooled itself by the expansion of air molecules, thus finally reaching a dew-point temperature resulting in widespread cloudiness. All clouds consist of minute water droplets, ice crystals, or a combination of both.
OBS: The term ""cloud formation"", in cloud physics, can also mean ""a particular arrangement of cloud, a striking development of a cloud"".