Cloud Computing

Clouds are dense, voluminous masses of ice crystals and small water droplets suspended in the Earth's atmosphere. They have various functions in the climate system, such as cooling the planet by reflecting light into space. Cloud formation occurs when airborne water vapor condenses into observable water droplets or ice crystals. Airborne water vapor and aerosols, including dust and salt, collide with each other, forming condensation. When the air becomes too saturated to store more water vapor, clouds form due to evaporation or condensation at the dew point. Clouds significantly influence the weather and climate of the planet. They are essential during rain or snow, reflecting heat back to the Earth during the night and blocking the sun's rays during the day. Different types of clouds are classified based on their altitude, such as high clouds (circus, Cirrostratus, Cirrocumulus), middle clouds (Altostratus, Altocumulus), low clouds (Stratocumulus, Nimbostratus), and clouds with extensive vertical development (Cumulus, Cumulonimbus).

Clouds are a collection of ice crystals and water droplets in the Earth's atmosphere, visible to the naked eye due to their large volume and density. They come in various varieties with unique characteristics, serving various climate system functions. Clouds reflect light into space, aiding in planet cooling. They form from the saturation of air with water vapor, with more in warm air than cold. As the air cools, the clouds enlarge and fall as precipitation in various forms, such as rain, drizzle, snowfall, sleet, or hail.

It is the process of turning invisible water vapor into visible water droplets or ice crystals.

• The air is always filled with water vapor and aerosol particles like dust and salt, which regularly collide with one another.
• Water vapor condenses when the air cools and sticks to these aerosol particles.
• As bigger water droplets progressively develop around the aerosol particles, the condensation process keeps on.
• Clouds form as more droplets of water come together, when the air reaches a saturation point and is unable to retain any more water vapor.
• There are two ways in which this saturation might result in condensation:
  • either the air becomes more saturated due to evaporation or
  • condensation starts when the air cools down to the dew point, which is the temperature at which condensation starts.
• The air's capacity to contain water vapor increases with temperature. But when the air rises and cools, it can no longer hold as much water vapor, which causes condensation and clouds to form.
• The condensation level is the height at which clouds begin to develop and the dew point is attained.

The formation of clouds and the rising and cooling of the air are caused by five different factors:

1. Surface heating – This occurs when the sun heats the earth, heating the air that comes into touch with it and causing it to rise. Thermals are the term used to describe the ascending columns. Cumulus clouds are typically created by surface heating.
2. Topography or orographic forcing – Cloud formation may be influenced by the topography, or the contours and characteristics of the region. Air cools as it rises when it is forced to do so over a barrier made of hills or mountains. This is how layered clouds are often created.
3. Frontal – Along fronts, clouds are created when a mass of warm air rises over a mass of cold, dense air across wide distances. The line separating warmer, humid air from colder, drier air is called a "front."
4. Convergence – Where air streams converge, or flow together, they are compelled to rise from their separate paths. Cumulus clouds and showery weather may result from this.
5. Turbulence – A sudden change in wind speed with height creating turbulent eddies in the air.

There are several types of clouds, and each has a distinct height and set of properties. According to their heights, these are the primary categories of clouds:

1. High Cloud:
   • High-level clouds have the prefix "cirro" and are found over 20,000 feet.
   • Cold tropospheric temperatures cause ice crystal clouds that appear thin, streaky, and white, even at low light angles. For example, just before sunset, the clouds might take on a variety of colors.
   • Here, the cloud types that are present include Cirrus, Cirrostratus, and Cirrocumulus.
   
   
   1. Cirrus Cloud:
      • White, thin filaments that resemble detached clouds, primarily in the shape of narrow bands or patches.
      • They might resemble silky shine or fibrous (hair-like).
      • Ice crystals make up cirrus clouds in every case, and the degree of crystal separation determines how transparent the clouds are.
      • These clouds often don't significantly lessen the sun's brightness when they pass over its disk. If they are really thick, they might block out its light and completely cover up its outline.
      • Cirrus is frequently brilliant yellow or red in color before dawn and after dusk. These clouds start out brighter than ordinary clouds and fade considerably longer. They become gray sometime after sunset.
      • Cirrus near the horizon is frequently yellowish in hue at all times of the day; this is because of the distance and the thick air that the light rays pass through.
   2. The Cirrostratus
      • White, transparent veil clouds that have a smooth or fibrous (hair-like) look.
      • An extremely large sheet of cirrostratus almost invariably ends up covering the whole sky.
      • The halo effect that the sun or moon almost invariably creates in a layer of cirrostratus distinguishes a milky veil of fog (or thin stratus) from a veil of Cirrostratus with a similar look.
   3. Cirrocumulus
      • Cloud layer or thin, white region that is devoid of shade.
      • In the shape of roughly uniformly ordered grains or ripples, they are made up of minuscule components.


2. Middle Altitude Clouds:
   • The word "alto" refers to the types of clouds that are located between 6,500 and 20,000 feet in the middle troposphere.
   • These clouds can consist of liquid water droplets, ice crystals, or a mix of the two, including supercooled droplets (i.e., liquid droplets whose temperatures are below freezing), depending on the altitude, season, and vertical temperature structure of the troposphere.
   • Altostratus and altocumulus clouds are the two primary types of mid-level clouds.
   1. Altostratus
      • Sheets of gray or bluish clouds, or layers of fibrous or striated clouds, covering all or part of the sky.
      • They are sufficiently thin to sometimes let the sun be seen through ground glass.
      • Neither the shadows of things on the ground nor the halo effect are evident in altostratus clouds.
   2. Altocumulus
      • Gray or white patches, sheets, or stratified clouds, typically made up of spherical masses, rolls, or laminae (plates).
      • They might be widespread or somewhat fibrous.
      • A colourful ring is created when the edge of altocumulus, or a thin, semi-transparent patch of it, passes in front of the sun or moon. It appears within a few degrees of the sun or moon and has a red outside and a blue inside.


3. Low Altitude Clouds:
   • The terms "Strato" and "Cumulo," which refer to different types of low-level clouds, are used to refer to them without any prefix. Under 6500 feet, low clouds are made mostly of ice crystals (and snow), with the exception of cold winter storms when they are mostly composed of liquid water droplets or even supercooled droplets.
   • Stratus and cumulus are the two primary forms of low clouds; the former develops horizontally and the latter vertically.
   1. Nimbostratus
      • These are the rain cloud that never stopped. Thinning Altostratus is responsible for this layer of gloomy gray clouds that is scattered by snow or rain.
      • It is sufficiently thick all throughout to block out the sun.
      • The downpour keeps coming, lowering the cloud base.
   2. Stratocumulus
      • Patches, sheets, or layers of gray or white clouds that almost always have black patterns that give them a honeycomb appearance, and spherical masses or rolls.
      • Except for a mass of streaks of rain appearing to hang under a cloud and evaporating before reaching the ground,they are non-fibrous and may or may not be merged.
   3. Stratus
      • A consistent, mostly gray layer of clouds that can generate snow grains, ice prisms, or drizzle if it is thick enough.
      • When this cloud allows the sun to be seen, its outline is easily evident.
      • Frequently, a blue sky is observed when a stratus layer fragments and disappears.


4. Vertical Clouds:
   • These are clouds that reach up into the atmosphere from lower to higher altitudes.
   • The strong convectional circulation that traps and propels the moisture in the clouds higher up is what causes them to develop through thermal convection or frontal lifting.
   • The Cumulonimbus cloud is an illustration of a vertical cloud.
   
   
   1. Cumulus
      • Detachable, usually dense clouds with distinct contours that grow vertically into towering mounds, domes, or towers with protruding upper sections that frequently resemble cauliflowers.
      • These clouds have somewhat dark, horizontal bottoms, and bright white, sunny portions.
   2. Cumulonimbus
      • The thunderstorm cloud resembles a massive tower or mountain and is thick and heavy.
      • The upper part is almost always flattened in the form of a large plume or anvil, and is typically smoother, fibrous, or striated.
      • There are frequently low, jagged clouds beneath this cloud, which is frequently quite black, and which may or may not combine with the base.
      • Tornadoes and hail can also be produced by cumulonimbus clouds.


5. Foggy Clouds:
   • Stratus cloud layer that sits on top of or near the earth. They form at close proximity to the surface.
   • Sometimes they have really poor visibility, so it's hard to see anything farther away than sixty.
   
   

   Shelf Clouds

   • Arcus clouds, often referred to as shelf clouds, are frequently linked to strong storm systems and are frequently described as rotating, wall clouds, or funnel clouds.
   • Occasionally, these clouds can be observed behind cumulonimbus clouds, which are tall, dense clouds that produce heavy rain.
   • They frequently show up before intense thunderstorms that bring with them torrential rain, high gusts, and even hail or tornadoes.
   • Formation:
     • Warm, humid air may be forced upward when a chilly downdraft from a cumulonimbus cloud hits the ground and spreads quickly along the surface.
     • Warm air is forced upward by the descending cold air, resulting in condensation and the creation of clouds. The characteristic horizontal form and look of a shelf cloud are produced by this technique.

   
   

   International Cloud Atlas:

   • All members of the World Meteorological Organization utilize a categorization system for clouds and other meteorological phenomena, which is described in the International Cloud Atlas.
   • Along with pictures of clouds and other meteorological events, it also has a handbook of standards.
   • The latest update was made thirty years ago, and it was first published in the 19th century.
   • The International Cloud Atlas was digitized and expanded upon in its 2017 edition.

Cloud seeding is a method of artificially generating rain by implanting clouds with particles like silver iodide crystals. It uses planes to spray clouds with chemicals to condense smaller particles into larger rain droplets.

• There are three methods: static cloud seeding, dynamic cloud seeding, and hygroscopic cloud seeding.
• Static cloud seeding involves introducing ice nuclei into cold clouds, which can trigger the formation of ice crystals or snowflakes.
• Dynamic cloud seeding boosts vertical air currents
• Hygroscopic cloud seeding sprays fine particles of hygroscopic materials through flares or explosives into warm clouds. These particles act as cloud condensation nuclei, increasing the number and size of cloud droplets, enhancing reflectivity and stability.
• Cloud seeding is used to enhance winter snowfall, increase mountain snowpack, prevent hailstorms, dissipate fog, induce rainfall in drought-prone regions, and reduce air pollution. However, it requires moisture-filled clouds, which are not always available or predictable. It is not suitable during high flood risk or busy holiday travel periods.

Clouds appear white due to the tightly packed water droplets and ice crystals, which reflect sunlight. These particles scatter all colors of light, making the viewer perceive all wavelengths as white light. However, during rain, clouds appear dark or gray due to their particulate density, as water vapor binds together into raindrops, leaving large spaces between them, resulting in less light reflection and a darker appearance. While we are seeing use of cloud seeding in middle eastern countries like UAE to improve rainfall, it is not without its challenges. Cloud seeding may have negative environmental and health effects, such as altering the natural water cycle, contaminating soil and water with chemicals, or affecting the local climate.