How are clouds formed?
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It gets cooler as you go higher in the atmosphere. The water vapour in the air condenses on the dust particles forming tiny water droplets. These droplet float in the air. Such clusters of droplets is what we call clouds.
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Because the air closer to the earth isn't always at the correct temperature and humidity level to create clouds.
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Clouds are located in the troposphere.\nIn the colder regions the different clouds form about 6000 feet lower.\nHIGH CLOUDS\n16,500 feet and up\nIn height order (probably)\nCirrus (Ci) \nCirrus uncinus \nCirrus Kelvin-Helmholtz colombia \nCirrostratus (Cs) \nCirrocumulus (Cc) \nPileus \nContrail\n\n6,500 and 16,500 feet\nMIDDLE CLOUDS\nIn height order (probably)\nAltostratus (As) \nAltostratus undulatus \nAltocumulus (Ac) \nAltocumulus undulatus \nAltocumulus mackerel sky \nAltocumulus castellanus \nAltocumulus lenticularis\n\nLOW CLOUDS\n6,500 feet and lower\nIn Height Order (Probably)\nStratus (St) \nNimbostratus (Ns) \nCumulus humilis (Cu) \nCumulus mediocris (Cu) \nStratocumulus (Sc)\n~~~Fog is considered a cloud that forms above sea level.\n\nVERTICAL CLOUDS\n(can form at any height)\nCumulonimbus (associated with heavy precipitation and thunderstorms) (Cb) \nCumulonimbus incus \nCumulonimbus calvus \nCumulonimbus with mammatus \nCumulus congestus \nPyrocumulus
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Clouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals. This can happen in three ways.\n\n1. The air is cooled below its saturation point. This happens when the air comes in contact with a cold surface or a surface that is cooling by radiation, or the air is cooled by adiabatic expansion (rising). This can happen\n\nalong warm and cold fronts (frontal lift), \nwhere air flows up the side of a mountain and cools as it rises higher into the atmosphere (orographic lift), \nby the convection caused by the warming of a surface by insolation (diurnal heating), \nwhen warm air blows over a colder surface such as a cool body of water. \n2. Clouds can be formed when two air masses below saturation point mix. Examples are breath on a cold day, aircraft contrails, and Arctic sea smoke.\n\n3. The air stays the same temperature but absorbs more water vapor into it until it reaches saturation.\n\n\nand there's lots more at....
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A cumulonimbus cloud forms in rising air (updraft).  The air cools as it rises, and at a certain point the water vapor in the air condenses into water droplets, forming a cloud.  Around a large Cb there is often downdraft - the air gets warmer as it subsides, and any water droplets (=clouds) will evaporate.
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Water vapor is transparent (for most purposes) and so mere humidity in the atmosphere can't be a cloud. Since clouds don't have motors keeping them in the air, and yet stay there for hours in some cases, they can't be solid, for if they were, they'd fall out of the sky and we'd find cloud bits laying around on the ground. And the same is true for liquid as well. \n\nSo what's a cloud? Mostly, it's very small bits, so small that air currents can keep them in the air. The bits can be solid (eg, ice crystals of which snowflakes are examples), or liquid (eg, little drops of water, of which rain is an example). In either case, enough of these small things begin to look white as light passes thorough them and is reflected and refracted and generally diverted. Kind of like the effect of fine particulate suspensions in water. They are sometimes referred to as milky looking. Indeed, milk is white for a similar reason.\n\nThese are usually formed around dust bits, for real. High humidity (forced by cooling temperatures) produces supercooling (ie, ready to condense, if a trigger can be found). The dust motes provides the trigger. With updraft winds, a condensed drop can grow pretty large. And if it goes high enough, and gets cold enough, the drop can freeze (and thus make hail). If the orignal condensation is sufficiently cold, then water will be added to an ice crystal. With the proper history, such crystals become snowflakes.
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Clouds are water vapor. Think of it like a pocket of fog in the sky.
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Heat from the sun that warms water in the Oceans, rivers,and lakes. The water evaporates goes up inot the clouds, evaporated watre dropplets cling to dust particles in the atmoshpere, These become clouds, and as soon as enough water is clinging to one drop it beginn, rivers to rain, as if the clouds are to heavy to hold anymore. If it is cold then it will snow. This falls to the ground and (if snow melts) runs into the ocean rivers and lakes. REpeat Process with heat from the sun. ^^
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Cloud condensation nuclei or CCNs (also known as cloud seeds) are small particles (typically 0.0002 mm, or 1/100 th the size of a cloud droplet [1]) about which cloud droplets coalesce. Water requires a non-gaseous surface to make the transition from a vapour to a liquid. 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 below 0 °C (32 °F) before droplets spontaneously form (this is the basis of the cloud chamber for detecting subatomic particles). In above freezing temperatures the air would have to be supersaturated to around 400% before the droplets could form.\n\nThe concept of cloud condensation nuclei has led to the idea of cloud seeding, that tries to encourage rainfall by seeding the air with condensation nuclei appropriately.
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no clouds are not solid they are made  up of water  vapor and gas. Clouds are formed when air contains as much water vapor (gas) as it can hold. This is called the saturation point, and it can be reached in two ways. First, moisture accumulates until it reaches the maximum amount the volume of air can hold. The other method reduces the temperature of the moisture filled air, which in turn lowers the amount of moisture it can contain. Saturation, therefore, is reached through evaporation and condensation, respectively. When saturation occurs, moisture becomes visible water droplets in the form of fog and clouds.\n\nIt should be noted that condensation by itself does not cause precipitation (rain, snow, sleet, hail). The moisture in clouds must become heavy enough to succumb to gravity and return to earth's surface. This occurs through two processes. In cold clouds ice crystals and water droplets exist side by side. Due to an imbalance of water vapor pressure, the water droplets transfer to the ice crystals. The crystal seventually grow heavy enough to fall to earth. In the second process, water droplets in warm clouds collide and change their electric charge.Droplets of unlike charge attract one another and merge, thereby growing until they have sufficient weight to fall.\n\nThere is no difference between fog and clouds other than altitude. Fog is defined as a visible moisture that begins at a height lower than 50 feet. If the visible moisture begins at or above 50 feet, it is called a cloud. Two common types of fog are called radiation fog and advection fog. Radiation fog forms during the night as the earth's surface cools and the air immediately above it cools in turn by conduction. If the air is moist enough, the cooling causes it to reach saturation and visible water droplets form. We often call this type of fog ground fog because it lies so close to the surface. Advection fog forms when warm moist air moves over a colder surface (advection means to move horizontally). A perfect example is on the west coast of continents. Prevailing westerly winds move moist air from over a warm ocean area to over the colder waters off the coast. Fog forms and is carried by the westerly over the land.\n\nClouds can form anywhere in the troposphere, and although condensed liquid, they are light enough to float in the air and move from place to place by the wind. Clouds are classified according to appearance and height. Based on appearance, there are two major types: Clouds of vertical development, formed by the condensation of rising air; and clouds that are layered, formed by condensation of air without vertical movement. When clouds are classified by height, there are four classes: high, middle, low, and vertical development.\n\nCloud names, of which there are twelve, combine appearance and height. A brief description of the root name will indicate this combination of features.
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3 things r neede for cloud formation...cooling of air, presence of water vapour (relative humidity shud be close to 100%), and condensation nuclei( like dust particles).\ndunno who found it, sorry
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Storms are created when a center of low pressure develops, with a system of high pressure surrounding it. This combination of opposing forces can create winds and result in the formation of storm clouds, such as the cumulonimbus. Small, localized areas of low pressure can form from hot air rising off hot ground, resulting in smaller disturbances such as dust devils and whirlwinds.
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The clouds floating overhead contain water vapor and cloud droplets, which are small drops of condensed water. These droplets are way too small to fall as precipitation, but they are large enough to form visible clouds. Water is continually evaporating and condensing in the sky. If you look closely at a cloud you can see some parts disappearing (evaporating) while other parts are growing (condensation). Most of the condensed water in clouds does not fall as precipitation because their fall speed is not large enough to overcome updrafts which support the clouds. For precipitation to happen, first tiny water droplets must condense on even tinier dust, salt, or smoke particles, which act as a nucleus. Water droplets may grow as a result of additional condensation of water vapor when the particles collide. If enough collisions occur to produce a droplet with a fall velocity which exceeds the cloud updraft speed, then it will fall out of the cloud as precipitation. This is not a trivial task since millions of cloud droplets are required to produce a single raindrop. A more efficient mechanism (known as the Bergeron-Findeisen process) for producing a precipitation-sized drop is through a process which leads to the rapid growth of ice crystals at the expense of the water vapor present in a cloud. These crystals may fall as snow, or melt and fall as rain.
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It tends to be over land, because precipitation forms because of water saturation of the atmosphere; this doesn't really change too much on the open ocean.  But inland, there is a loss of water saturation, therefore clouds containing saturated water will tend to precipitate water (rain).
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The shape is completely random, based on how air currents (wind and updrafts) are moving around and inside the cloud. You get so many cloud shapes over time that a few random patterns are bound to resemble something else we're familiar with, such as a heart or a dog.
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The mechanism of Cloud formation is still not understood. Researchers are now applying Chaos Theory in the study and modelling of cloud behavior.\n\nWe "see" clouds only when the high moisture regions are sufficiently close to refract and reflect light. Actually they are highly dynamic systems.
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wikipedia.com\n\n\nA cloud is a visible mass of condensed droplets or ice crystals suspended in the atmosphere above the surface of the Earth or another planetary body. The branch of meteorology that studies clouds is nephology.\n\nOn Earth, the condensing substance is water vapor, which forms small droplets of water (typically 0.01 mm of ice crystals) that, when surrounded with billions of other droplets or crystals, are visible as clouds. Clouds reflect all visible wavelengths of light equally and are usually white, but they can appear grey or even black if they are so thick or dense that sunlight cannot pass through.\nContents\n[hide]\n\n    * 1 Cloud formation and properties\n          o 1.1 "Hot Ice" and "Ice Memory" in cloud formation\n    * 2 Cloud classification\n          o 2.1 High clouds (Family A)\n          o 2.2 Middle clouds (Family B)\n          o 2.3 Low clouds (Family C)\n          o 2.4 Vertical clouds (Family D)\n          o 2.5 Other clouds\n          o 2.6 Cloud fields\n    * 3 Colors of clouds\n    * 4 Global dimming\n    * 5 Global brightening\n    * 6 Clouds on other planets\n    * 7 See also\n    * 8 External links\n\n[edit]\n\nCloud formation and properties\nA variety of cloud formations.\nEnlarge\nA variety of cloud formations.\nGlobal scheme of cloud optical thickness.\nEnlarge\nGlobal scheme of cloud optical thickness.\n\nClouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals. This can happen in three ways.\n\n1. The air is cooled below its saturation point. This happens when the air comes in contact with a cold surface or a surface that is cooling by radiation, or the air is cooled by adiabatic expansion (rising). This can happen\n\n    * along warm and cold fronts (frontal lift),\n    * where air flows up the side of a mountain and cools as it rises higher into the atmosphere (orographic lift),\n    * by the convection caused by the warming of a surface by insolation (diurnal heating),\n    * when warm air blows over a colder surface such as a cool body of water.\n\n2. Clouds can be formed when two air masses below saturation point mix. Examples are breath on a cold day, aircraft contrails, and Arctic sea smoke.\n\n3. The air stays the same temperature but absorbs more water vapor into it until it reaches saturation.\n\nThe water in a typical cloud can have a mass of up to several million tonnes. However the volume of a cloud is correspondingly high, and the net density of the relatively warm air holding the droplets is low enough that air currents below and within the cloud are capable of keep it suspended. As well, conditions inside a cloud are not static: water droplets are constantly forming and re-evaporating. A typical cloud droplet has a radius on the order of 1 x 10-5 m and a terminal velocity of about 1-2 cm/s. This give these droplets plenty of time to re-evaporate as they fall into in the warmer air beneath the cloud.\nCumulonimbus cloud\nEnlarge\nCumulonimbus cloud\n\nMost water droplets are formed when water vapor condenses around a condensation nucleus, a tiny particle of smoke, dust, ash, or salt. In supersaturated conditions, water droplets may act as condensation nuclei.\n\nWater droplets large enough to fall to the ground are produced in two ways. The most important is through the Bergeron Process, theorized by Tor Bergeron, in which supercooled water droplets and ice crystals in a cloud interact to produce the rapid growth of ice crystals, which precipitate from the cloud and melt as they fall. This process typically takes place in clouds with tops cooler than -15°C. The second most important process is the collision and wake capture process, occurring in clouds with warmer tops, in which the collision of rising and falling water droplets produces larger and larger droplets, which are eventually heavy enough to overcome air currents in the cloud and the updraft beneath it and fall as rain. As a droplet f