1 / 21

Cloud Formation and Types

Cloud Formation and Types. Why Do Clouds Form?. Clouds need three things to form: Cooling Condensation Nuclei Saturated Air. What Causes Cooling?. There are Four Processes that lead to the cooling of air- #1 Convective Cooling Rising air expands because pressure decreases

oprah
Download Presentation

Cloud Formation and Types

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Cloud Formation and Types

  2. Why Do Clouds Form? • Clouds need three things to form: • Cooling • Condensation Nuclei • Saturated Air

  3. What Causes Cooling? There are Four Processes that lead to the cooling of air- • #1 Convective Cooling Rising air expands because pressure decreases Expansion causes the air to become cooler • Adiabatic Temperature Changesare changes in temperature from the expansion or compression of air

  4. Adiabatic Temperature Change(Convective Cooling Continued) • For dry air, temperature changes 1ºC every 100 meters in elevation change • 5.4ºF for every 1000 feet • For moist air, the cooling rate varies from 0.5ºC per 100 m for air with a high moisture content to 0.9ºC per 100 m for air with a very low moisture content • Average is 0.7ºC per 100 m

  5. Convective Cooling (Continued) • When the rising air reaches the dew point temperature, water vapor begins to condense • The condensation level is the height above the ground at which condensation takes place

  6. #2 Forceful Lifting • An event occurs that forces the air to rise • Air moving up and over a mountain

  7. #3Temperature Changes • Two air masses with different temperatures mix • The temperature change of the combined air masses may be cooler than the dew point

  8. #4 Advective Cooling • Warm, moist air moving over cool land or water causes the air temperature to drop • Forms low clouds or fog

  9. Cloud Condensation Level

  10. Condensation Nuclei • The water vapor needs a surface on which to condense. • Condensation nuclei are tiny, less than 0.001 mm in diameter. There MUST be solid particles in the air for the water vapor to condense onto. • Examples include: • Suspended particles of atmospheric dust • mineral particles • ash from fires • volcanic dust • microscopic organisms • vaporized meteors • salt from sea spray

  11. Saturated Air • Air temperature must be equal to the dew point. • Thus, 100% humidity. . . Clouds form!

  12. Let’s Make a Cloud! Magic?!. . . No, science.

  13. Cloud Types 1 • Stratus Clouds • sheet-like, or layered. • Cumulus Clouds • puffy, like cotton balls. • Cirrus Clouds • thin and wispy.

  14. Cloud Types 2 • High Clouds (above 6,000 m) • Cirrus • Cirrostratus • Mid-level Clouds • Altostratus • Altocumulus • Low-level Clouds • Stratus • Cumulus, Cumulonimbus

  15. Cirrus Clouds (thin and wispy)

  16. Cirrostratus Clouds

  17. Altocumulus Clouds

  18. Fair-Weather Cumulus Clouds

  19. Cumulonimbus 1

  20. Cumulonimbus 2

  21. Finally, what do we call a cloud on the ground? FOG!

More Related