Cloud From Wikipedia, the free encyclopedia For other uses, see Cloud (disambiguation). Stratocumulus stratiformis cumulogenitus 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.[1] 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 Earths atmosphere becoming saturated due to either or both of two processes; cooling of the air and adding water vapor. With sufficient saturation, precipitation will fall to the surface; an exception is virga, which evaporates before reaching the surface. Clouds in the troposphere, the atmospheric layer closest to Earths surface, have Latin names due to the universal adaptation of Luke Howards nomenclature. It was introduced in December 1802 and became the basis of the modern classification system. Synoptic surface weather observations use code numbers to record and report any type of tropospheric cloud visible at scheduled observation times based on its height and physical appearance. The international cloud classification system is based on the fact that these tropospheric aerosols in their most basic forms can show free-convective upward growth into low or vertical heaps of cumulus, appear in non-convective layered sheets at various altitudes as with low stratus and its higher variants, or take the form of high thin fibrous wisps of cirrus. In the case of low and vertical or multi-level clouds, prefixes are used whenever necessary to express variations or complexities in these basic forms. These include strato- for low cumulus layers with limited convection that show some stratus-like characteristics, cumulo- for complex highly convective vertical nimbus storm clouds, and nimbo- for thick stratus layers with sufficient vertical extent to produce moderate to heavy precipitation. For higher-based cloud types, the prefixes specify middle or high altitude ranges within the troposphere; alto- for middle, and cirro- for high. Cloud types prefixed by altitude range may be of simple non-convective stratiform structure or show slightly to moderately complex stratocumuliform structure due to limited convective activity. Free-convective clouds with potentially more complex forms are not prefixed by altitude range. Whether or not a cloud is classified as low, middle, or high level depends on the altitude range of its base above Earths surface. In the case of a layer or heap with significant vertical extent, the height of the top is also a factor that defines its altitude classification. A vertically developed cloud can initially form or have its base in the low or middle altitude range of the troposphere depending on the moisture content of the air, while the top can be in the middle or high range. Ten main genera can be identified by this system of Latin stems and prefixes, which can be subdivided into a total of about ninety sub-types. The latter are determined by dividing most of the genus types into species, which are then sub-divided into varieties where applicable, all of which have Latin names. Any of the ten genus-types can can become mother clouds whenever they partially of fully transform due to changing atmospheric conditions. Latin names are also given to accessory clouds and other supplementary features that are not further subdivisons within the basic system of nomenclature, but rather special cloud formations or precipitiation that sometimes accompany the regular cloud types. While a majority of clouds form in Earths troposphere, there are occasions when they can be observed at much higher altitudes in the stratosphere and mesosphere. Clouds that form above the troposphere have common names for their main types, but are sub-classified alpha-numerically rather than with the elaborate system of Latin names given to cloud types in the troposphere. These three main atmospheric layers that can produce clouds, along with the lowest part of the cloudless thermosphere, are collectively known as the homosphere. Above this lies the heterosphere (which includes the rest of the thermosphere and the exosphere) that marks the transition to outer space. Clouds have been observed on other planets and moons within the Solar System, but, due to their different temperature characteristics, they are composed of other substances such as methane, ammonia, and sulfuric acid. Godbless Musiclovers!!! #CLOUDIANN :) shhhhhhhhh.....
Posted on: Sun, 03 Nov 2013 07:15:43 +0000