"is called ""Cumulus homogenitus"" and abbreviated as CUa. If a ""homogenitus"" cloud of one genus changes to another genus type, it is termed a ""homomutatus"" cloud. The international cloud classification divide the different ""genera"" in three main groups of clouds according to their altitude: Homogenitus clouds will be generated by different sources at those different levels. Despite the fact that the three genera of high clouds, ""Cirrus"", ""Cirrocumulus"" and ""Cirrostratus"", form at the top of the troposphere, far from the earth surface, they may have an anthropogenic origin. In this case, the process that causes their formation is almost always"
"Cirrus cloud Cirrus (cloud classification symbol: Ci) is a genus of atmospheric cloud generally characterized by thin, wispy strands, giving the type its name from the Latin word ""cirrus"", meaning a ringlet or curling lock of hair. This cloud can form at any altitude between and above sea level. The strands of cloud sometimes appear in tufts of a distinctive form referred to by the common name of ""mares' tails"". From the surface of Earth, cirrus typically appears white, or a light grey in color. It forms when water vapor undergoes deposition at altitudes above in temperate regions and above"
"of instability or convective activity. High clouds form at altitudes of in the polar regions, in the temperate regions and in the tropics. All cirriform clouds are classified as high and thus constitute a single genus ""cirrus"" (Ci). Stratocumuliform and stratiform clouds in the high altitude range carry the prefix ""cirro-"", yielding the respective genus names ""cirrocumulus"" (Cc) and ""cirrostratus"" (Cs). When limited-resolution satellite images of high clouds are analysed without supporting data from direct human observations, it becomes impossible to distinguish between individual forms or genus types, which are then collectively identified as ""high-type"" (or informally as ""cirrus-type"" even"
"Cloud condensation nuclei Cloud condensation nuclei or CCNs (also known as cloud seeds) are small particles typically 0.2 µm, or 1/100th the size of a cloud droplet on which water vapor condenses. Water requires a non-gaseous surface to make the transition from a vapour to a liquid; this process is called condensation. In the atmosphere, this surface presents itself as tiny solid or liquid particles called CCNs. When no CCNs are present, water vapour can be supercooled at about −13°C (8°F) for 5–6 hours before droplets spontaneously form (this is the basis of the cloud chamber for detecting subatomic particles)."
"However, why they have this shape or how they are formed is not known, but recent evidence suggests that the interaction of both radiation and precipitation may help to organize them on the mesoscale. The individual convective cells that collectively make up an actinoform cloud are quite shallow, with heights generally less than , and would be classified as stratocumulus clouds by an observer on the ground. Given the extensive mesoscale organization of these clouds, it is appropriate to describe them as mesoscale stratocumulus cloud systems (MSCS) in analogy with their deeper counterpart, the Mesoscale convective system. Actinoform clouds were"
"at 2047.5 cm due to stretching of a C=C bond. Along with the related dicarbon monosulfide (CCS), tricarbon monosulfide was made by a glow discharge though carbon disulfide vapour in helium. Microwave emission lines from rotational transitions matched up with previously unknown molecular lines from the Taurus Molecular Cloud 1. Maximal concentrations occurred with a carbon disulfide pressure of 0.02 torr. In molecular clouds the formation mechanism is speculated to be CCS + CH → CCCS + H. On dust grains in space the formation mechanism is theorised to be: CCC + HS → C•HSH → CCCS + H when"
"Cirrocumulus cloud Cirrocumulus is one of the three main genus-types of high-altitude tropospheric clouds, the other two being cirrus and cirrostratus. They usually occur at an altitude of to . Like lower altitude cumuliform and stratocumuliform clouds, cirrocumulus signifies convection. Unlike other high-altitude-tropospheric clouds like cirrus and cirrostratus, cirrocumulus includes a small amount of liquid water droplets, although these are in a supercooled state. Ice crystals are the predominant component, and typically, the ice crystals cause the supercooled water drops in the cloud to rapidly freeze, transforming the cirrocumulus into cirrostratus. This process can also produce precipitation in the form"
"clouds that form from to in polar areas, in temperate areas, and in tropical areas. Although altostratus forms mostly in the middle level of the troposphere, strong frontal lift can push it into the lower part of the high-level. The main hight-level stratiform cloud is cirrostratus which is composed of ice crystals that often produce halo effects around the sun. Cirrostratus forms at altitudes of in high latitudes, in temperate latitudes, and in low, tropical latitudes. Of the non-stratiform clouds, cumulonimbus and cumulus congestus are the most closely related to nimbostratus because of their vertical extent and ability to produce"
"Altocumulus castellanus cloud In meteorology, Altocumulus Castellanus (ACCAS) is a cloud type named for its tower-like projections that billow upwards from the base of the cloud. The base of the cloud can form as low as 2,000 metres (6,500 feet), or as high as 6,000 metres (20,000 feet). They are very similar to cumulus congestus clouds, but at a higher level and with the cloud heaps joined at the base. Castellanus clouds are evidence of mid-atmospheric instability and a high mid-altitude lapse rate. They may be a harbinger of heavy showers and thunderstorms and, if surface-based convection can connect to"
"Cumulonimbus cloud Cumulonimbus (from Latin ""cumulus"", ""heaped"" and ""nimbus"", ""rainstorm"") is a dense, towering vertical cloud, forming from water vapor carried by powerful upward air currents. If observed during a storm, these clouds may be referred to as thunderheads. Cumulonimbus can form alone, in clusters, or along cold front squall lines. These clouds are capable of producing lightning and other dangerous severe weather, such as tornadoes. Cumulonimbus progress from overdeveloped cumulus congestus clouds and may further develop as part of a supercell. Cumulonimbus is abbreviated Cb. Towering cumulonimbus clouds are typically accompanied by smaller cumulus clouds. The cumulonimbus base may"
"Mesoscale convective system A mesoscale convective system (MCS) is a complex of thunderstorms that becomes organized on a scale larger than the individual thunderstorms but smaller than extratropical cyclones, and normally persists for several hours or more. A mesoscale convective system's overall cloud and precipitation pattern may be round or linear in shape, and include weather systems such as tropical cyclones, squall lines, lake-effect snow events, polar lows, and Mesoscale Convective Complexes (MCCs), and generally form near weather fronts. The type that forms during the warm season over land has been noted across North America, Europe, and Asia, with a"
"view. Cumulonimbus cloud Cumulonimbus (from Latin ""cumulus"", ""heaped"" and ""nimbus"", ""rainstorm"") is a dense, towering vertical cloud, forming from water vapor carried by powerful upward air currents. If observed during a storm, these clouds may be referred to as thunderheads. Cumulonimbus can form alone, in clusters, or along cold front squall lines. These clouds are capable of producing lightning and other dangerous severe weather, such as tornadoes. Cumulonimbus progress from overdeveloped cumulus congestus clouds and may further develop as part of a supercell. Cumulonimbus is abbreviated Cb. Towering cumulonimbus clouds are typically accompanied by smaller cumulus clouds. The cumulonimbus base"
"the mid-tropospheric unstable layer, continued development of Castellanus clouds can produce cumulonimbus clouds. Altocumulus castellanus clouds are typically accompanied by moderate turbulence as well as potential icing conditions. For these reasons, flight through these clouds is often best avoided by aircraft. Altocumulus castellanus cloud In meteorology, Altocumulus Castellanus (ACCAS) is a cloud type named for its tower-like projections that billow upwards from the base of the cloud. The base of the cloud can form as low as 2,000 metres (6,500 feet), or as high as 6,000 metres (20,000 feet). They are very similar to cumulus congestus clouds, but at a"
"in the cold bottom layers while most of the light needed for photosynthesis in the warm top layer. Under this scenario, deprived of nutrients, marine phytoplankton would decline, as would sulfate cloud condensation nuclei, and the high albedo associated with low clouds. This is known as the CLAW hypothesis (named after the authors' initials of a 1987 ""Nature"" paper) but no conclusive evidence to support this has yet been reported. Cloud condensation nuclei Cloud condensation nuclei or CCNs (also known as cloud seeds) are small particles typically 0.2 µm, or 1/100th the size of a cloud droplet on which water"
"in tropical regions. It also forms from the outflow of tropical cyclones or the anvils of cumulonimbus clouds. Since cirrus clouds arrive in advance of the frontal system or tropical cyclone, it indicates that weather conditions may soon deteriorate. While it indicates the arrival of precipitation (rain), cirrus clouds only produce fall streaks (falling ice crystals that evaporate before landing on the ground). Jet stream-powered cirrus can grow long enough to stretch across continents while remaining only a few kilometers deep. When visible light interacts with the ice crystals in cirrus cloud, it produces optical phenomena such as sun dogs"
"""homogenitus"" get wide and it can exist for hours. In the later case, depending on the wind conditions ""Cca"" may evolve to ""Cirrus homogenitus"" (""aCi""), or ""Cirrostratus homogenitus"" (""Csa""). The existence and persistence of these three types of high anthropogenic clouds may indicate the approximation of air stability. In some cases, when there is a large density of air traffic, these high ""homogenitus"" may inhibit the formation of natural high clouds, because the contrails capture most of the water vapor. The intermediate layers of the troposphere are the regions with less influence of human activity. This region is far enough"
"They range from a few light years to dozens of light years across. While they are not technically cirrus clouds, the dust clouds are referred to as ""cirrus"" because of their similarity to the clouds on Earth. They also emit infrared radiation, similar to the way cirrus clouds on Earth reflect heat being radiated out into space. Footnotes Bibliography Cirrus cloud Cirrus (cloud classification symbol: Ci) is a genus of atmospheric cloud generally characterized by thin, wispy strands, giving the type its name from the Latin word ""cirrus"", meaning a ringlet or curling lock of hair. This cloud can form"
"Polar stratospheric cloud Polar stratospheric clouds (PSCs), also known as nacreous clouds (, from ""nacre"", or mother of pearl, due to its iridescence), are clouds in the winter polar stratosphere at altitudes of . They are best observed during civil twilight, when the Sun is between 1 and 6 degrees below the horizon, as well as in winter and in more northerly latitudes. They are implicated in the formation of ozone holes. The effects on ozone depletion arise because they support chemical reactions that produce active chlorine which catalyzes ozone destruction, and also because they remove gaseous nitric acid, perturbing"
"winds within a tropical cyclone, as well as its heaviest rainfall, are usually located under the coldest cloud tops in the CDO. It is a large region of thunderstorms surrounding the center of stronger tropical and subtropical cyclones which shows up brightly (with cold cloud tops) on satellite imagery. The CDO forms due to the development of an eyewall within a tropical cyclone. Its shape can be round, oval, angular, or irregular. Its development can be preceded by a narrow, dense, C-shaped convective band. Early in its development, the CDO is often angular or oval in shape, which rounds out,"
"they can grow into the precipitation-bearing congestus or cumulonimbus clouds. Cumulus clouds can be formed from water vapor, supercooled water droplets, or ice crystals, depending upon the ambient temperature. They come in many distinct subforms, and generally cool the earth by reflecting the incoming solar radiation. Cumulus clouds are part of the larger category of free-convective cumuliform clouds, which include cumulonimbus clouds. The latter genus-type is sometimes categorized separately as cumulonimbiform due to its more complex structure that often includes a cirriform or anvil top. There are also cumuliform clouds of limited convection that comprise stratocumulus (low-étage), altocumulus (middle-étage) and"
"source of fluoride anions. Caesium fluoride has the halite structure, which means that the Cs and F pack in a cubic closest packed array as do Na and Cl in sodium chloride. Notably, caesium and fluorine have the lowest and highest electronegativities, respectively, among all the known elements. Caesium chloride (CsCl) crystallizes in the simple cubic crystal system. Also called the ""caesium chloride structure"", this structural motif is composed of a primitive cubic lattice with a two-atom basis, each with an eightfold coordination; the chloride atoms lie upon the lattice points at the edges of the cube, while the caesium"
"according to WMO classification, nimbostratus. These clouds are formed from ice crystals, supercooled water droplets, or liquid water droplets. Low-étage clouds form at less than . The two genera that are strictly low-étage are stratus, and stratocumulus. These clouds are composed of water droplets, except during winter when they are formed of supercooled waterdroplets or ice crystals if the temperature at cloud level is below freezing. Two additional genera usually form in the low altitude range, but may be based at higher levels under conditions of very low humidity. They comprise the genera cumulus, and cumulonimbus, which along with nimbostratus,"
"In the tropical regions, this cloud covers around 70% of the region's surface area. Cirrus clouds often produce hair-like filaments—similar to the virga produced in liquid–water clouds—called fall streaks, and they are made of heavier ice crystals that fall from the cloud. The sizes and shapes of fall streaks are determined by the wind shear. Cirrus comes in four distinct species; Cirrus ""castellanus"", ""fibratus"", ""spissatus"", and ""uncinus""; which are each divided into four varieties: ""intortus"", ""vertebratus"", ""radiatus"", and ""duplicatus"". ""Cirrus castellanus"" is a species that has cumuliform tops caused by high-altitude convection rising up from the main cloud body. ""Cirrus"
"this may also be seen in conjunction with showers and thunderstorms). If it is seen after rain it usually means improving weather. Cirrocumulus cloud Cirrocumulus is one of the three main genus-types of high-altitude tropospheric clouds, the other two being cirrus and cirrostratus. They usually occur at an altitude of to . Like lower altitude cumuliform and stratocumuliform clouds, cirrocumulus signifies convection. Unlike other high-altitude-tropospheric clouds like cirrus and cirrostratus, cirrocumulus includes a small amount of liquid water droplets, although these are in a supercooled state. Ice crystals are the predominant component, and typically, the ice crystals cause the supercooled"
"and halos. Cirrus is known to raise the temperature of the air beneath the main cloud layer by an average of 10 °C (18 °F). When the individual filaments become so extensive that they are virtually indistinguishable from one another, they form a sheet of high cloud called cirrostratus. Convection at high altitudes can produce another high-based genus called cirrocumulus, a pattern of small cloud tufts that contain droplets of supercooled water. Cirrus clouds form on other planets, including Mars, Jupiter, Saturn, Uranus, and possibly Neptune. They have even been seen on Titan, one of Saturn's moons. Some of these"
"were C and C. A solid rotating graphite disk was used as the surface from which carbon was vaporized using a laser beam creating hot plasma that was then passed through a stream of high-density helium gas. The carbon species were subsequently cooled and ionized resulting in the formation of clusters. Clusters ranged in molecular masses, but Kroto and Smalley found predominance in a C cluster that could be enhanced further by allowing the plasma react longer. They also discovered that the C molecule formed a cage-like structure, a regular truncated icosahedron. For this discovery Curl, Kroto, and Smalley were"
"tropics. Cumulus congestus clouds are formed by the development of cumulus mediocris generally, though they can also be formed from altocumulus castellanus or stratocumulus castellanus as well. The ""congestus"" species of cloud can only be found in the genus ""cumulus"" and is designated as ""towering cumulus"" (Tcu) by the International Civil Aviation Organization. Congestus clouds are capable of producing severe turbulence and showers of moderate to heavy intensity. This species is classified as vertical or multi-étage and is coded C2 in the synop report. These clouds are usually too large and opaque to have any opacity or pattern-based varieties. Pyrocumulus"
"location of the jet stream. Cirrus vertebratus Cirrus vertebratus is a type of cirrus cloud. The name ""cirrus vertebratus"" is derived from Latin, meaning ""jointed, articulated, vertebrated"". Like cirrus intortus, the vertebratus species is exclusive to the cirrus genus. Cirrus vertebratus gives the impression of vertebrae in a spinal column, ribs, or a fish skeleton. The species is an unusual form of cirrus clouds and is formed by air moving parallel to the main cloud line. The gaps in the cloud occur where air is descending, while the ""ribs"" of the cloud correspond with areas of uplift. Their occurrence appears"
"Circumhorizontal arc A circumhorizontal arc is an optical phenomenon that belongs to the family of ice halos formed by the refraction of sun- or moonlight in plate-shaped ice crystals suspended in the atmosphere, typically in cirrus or cirrostratus clouds. In its full form, the arc has the appearance of a large, brightly spectrum-coloured band (red being the topmost colour) running parallel to the horizon, located far below the Sun or Moon. The distance between the arc and the Sun or Moon is twice as far as the common 22-degree halo. Often, when the halo-forming cloud is small or patchy, only"
"irradiated with visible or UV light. THis reaction has been reproduced in a solid argon matrix. Tricarbon monosulfide has been detected in molecular clouds in space, such as Taurus Molecular Cloud 1 and Orion KL. The ratio of tricarbon monoxide to tricarbon monosulfide reflects the ratio of sulfur to oxygen in the cloud. The ratio of concentration of sulfur to oxygen analogues follows the same pattern. The clouds can be cold and dark, or warm. CCCS has also been found in the stellar envelope of carbon rich AGB stars, including in IRC+10216. Tricarbon monosulfide Tricarbon monosulfide (CS) or tricarbon sulfur"
"then dissipates into cirrus. Cirrocumulus clouds come in four species which are common to all three genus-types that have limited-convective or stratocumuliform characteristics: ""stratiformis"", ""lenticularis"", ""castellanus"", and ""floccus"". They are iridescent when the constituent supercooled water droplets are all about the same size. Altocumulus clouds are a mid-level cloud that forms from high to in polar areas, in temperate areas, and in tropical areas. They can have precipitation and are commonly composed of a mixture of ice crystals, supercooled water droplets, and water droplets in temperate latitudes. However, the liquid water concentration was almost always significantly greater than the concentration"
"main genera in the family of high clouds: cirrus, cirrocumulus, and cirrostratus. Cirrostratus clouds commonly produce halos because they are composed almost entirely of ice crystals. Cirrocumulus and cirrostratus are sometimes informally referred to as ""cirriform clouds"" because of their frequent association with cirrus. They are given the prefix ""cirro-"", but this refers more to their altitude range than their physical structure. Cirrocumulus in its pure form is actually a high cumuliform genus, and cirrostratus is stratiform, like altostratus and lower based sheet clouds. Cirrocumulus clouds form in sheets or patches and do not cast shadows. They commonly appear in"
"Arcus cloud An arcus cloud is a low, horizontal cloud formation, usually appearing as an accessory cloud to a cumulonimbus. Roll clouds and shelf clouds are the two main types of arcus. Arcus clouds most frequently form along the leading edge or ""gust fronts"" of thunderstorm outflow; some of the most dramatic arcus formations mark the gust fronts of derecho-producing convective systems. Roll clouds also may arise in the absence of thunderstorms, forming along the shallow cold air currents of some sea breeze boundaries and cold fronts. A shelf cloud is a low, horizontal, wedge-shaped arcus cloud. A shelf cloud"