18.2[1] cloud formation

18.2[1] cloud formation

• 1.
  18.2- Cloud Formation
• 2.
  Condensation Condensation canform dew, fog, or clouds and they all need saturated air to develop.
• 3.
  Adiabatic Temperature ChangesTemperature changes that happen even though heat isn’t added or subtracted are called abatic temperature changes. When air is allowed to expand it cools, and when it is compressed, it warms.
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  Expansion and CoolingDry adiabatic rate- the rate of cooling or heating apples only to unsaturated air. If a parcel of air rises high enough, it will eventually cool to its dew point. Latent heat works against the adiabatic cooling. The slower rate of cooling caused by the addition of latent heat is called the wet adiabatic rate.
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  Processes That LiftAir Clouds form because there is some mechanical process that forces air to rise. Four mechanisms that can cause air to rise are orographic lifting, frontal wedging, convergence, and localized convective lifting.
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  Orographic Lifting Mountainsacting as barriers to the flow of air, forcing the air to ascend; the air cools adiabatically, and clouds and precipitation may result.
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  Frontal Wedging Theboundary between two adjoining air masses having contrasting characteristics.
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  Convergence Whenever airin the lower atmosphere flows together, lifting occurs.
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  Stability Ifthe volume of air was forced to rise, its temperature would drop because of expansion. Stable air tens to remain in its original position while unstable air tends to rise. Air stability is determined by measuring the temperature of the atmosphere at various heights. Temperature Inversion- a layer of limited depth in the atmosphere of limited depth where the temperature increases rather then decreases the height.
• 10.
  Stability and DailyWeather Clouds with the lifting of unstable air are towering and often generate thunderstorms and occasionally even a tornadoes.
• 11.
  Condensation Condensation happenswhen water vapor in the air changes to a liquid which may be in the form of dew, fog, or clouds. When condensation occurs in the air above the ground, tiny bits of particulate matter is called condensation nuclei .