In meteorology, a cloud is a visible mass of liquid droplets or frozen crystals made of water or various chemicals suspended in the atmosphere above the surface of a planetary body. These suspended particles are also known as aerosols and are studied in the cloud physics branch of meteorology. Terrestrial cloud formation is the result of air in any of the lower three principal layers of Earth's atmosphere (collectively known as the homosphere) becoming saturated due to either or both of two processes: cooling of the air, and adding water vapor.
Clouds in the troposphere, the atmospheric layer closest to Earth's surface, have Latin names due to the universal adaptation of Luke Howard's nomenclature. It was formally proposed in December 1802 and published for the first time the following year. It became the basis of a modern international system that classifies these tropospheric aerosols into several physical forms which can appear in various altitude ranges or étages.
Uploaded: Nov 6, 2015