Jake Howard

1. Clouds and
Precipitation
Jake Howard

2. Adiabatic Temperature Changes and
Expansion & Cooling
 When air is heated, it becomes less
dense and rises above the cooler air, it
continues to expand because of the
lesser amounts of pressure as it goes
higher into the atmosphere.
 The molecules need energy to spread
out, which makes them vibrate slower.
This causes the temperature of these
air molecules to drop. This is adiabatic http://www.kidsgeo.
com/geography-for-
cooling. kids/0070-
adiabatic-
temperature-
changes.php

3. Orogrpahic Lifting
 Orographic Lifting is when an
air mass is forced from a low
elevation to a higher
elevation.
 As the air mass gains altitude
it cools down which will http://www.wateren
increase the relative humidity cyclopedia.com/Ce-
Cr/Climate-
to 100% and create clouds. Moderator-Water-
as-a.html

4. Frontal Wedging
 Frontal wedging is when warm air and cool air collide, this
produces a front.
 The cooler air acts as a barrier and the warmer air rises.
The cooler air is denser and the warmer air is less dense.
 This process, like orographic lifting, also lifts air and is a
weather producer.
http://www.geo.
hunter.cuny.edu
/~tbw/wc.notes/
4.moisture.atm.
stability/frontal
_wedging.htm

5. Convergence
 When air in the lower
atmosphere flows together,
lifting happens.
 When air flows from multiple
directions if must go
somewhere.
http://www.jamstec.go.j
 The uplifting of these winds p/e/about/press_release/
coming from different 20080313/
directions ends up forming a
clouds.

6. Localized Convective Lifting
 On hot days, usually in the summer, the earth’s surface
is heated unequally. This could possibly cause pockets
of air to me warmer than the surrounding air.
 The rising parcels of warmer air are thermals. When
thermals rise about the level of condensation clouds
will form.
http://www.richhoffm
anclass.com/chapter4.
html

7. Stability
 Air stability is measured by the temperature
of the atmosphere and different heights.
 Stable air will not rise by itself, but some
processes will force this air above the
surface of the Earth, which will then form
clouds. These clouds are often huge and
generate thunderstorms.
http://ocw.usu.edu/Fore
 Warmer air is less dense. And example of st__Range__and_Wildlif
e_Sciences/Wildland_Fir
density difference in stability is a hot air e_Management_and_Pla
balloon. A hot air balloon will continue to nning/Unit_7__Atmosph
rise as long as the air inside it is warmer eric_Stability_and_Insta
bility_1.html
than the surrounding air, therefore less
dense.

8. Condensation
 When something changes from a
gas to a liquid. The opposite of
vaporization.
 Happens when vapor is cooled or
compressed to its highest possible
saturation.
 For example it could form on the
wing of an airplane that is
traveling through a low pressure
area.

9. Types of clouds
 There are 4 types of clouds, High, Low, Middle, and
Vertical. There are different clouds which fall under
these types.

10. High Clouds
 Thin clouds that are blown
long ways by the wind. They
move across the sky west to
east.
 They are usually involved
with good weather.
 They often cover the entire
sky.

11. Middle Clouds
 Middle clouds are altostratus clouds.
 They are formed by water droplets and
appear gray or blue and fluffy.
 Sometimes parallel waves across the sky.
 These clouds might appear on a warm
summer morning, signaling that a
thunderstorm may come later in the
day.
 Often cover the entire sky.

12. Low Clouds
 Low clouds are stratus clouds.
 They are they gray clouds that
cover the entire sky.
 Do not usually produce
precipitation.
 When thick fog lifts it forms
these clouds.

13. Clouds of Vertical development
 These are called cumulus clouds.
 Look like pieces of floating cotton.
 The base of these clouds is often flat.
 They are the large clouds, they can sometimes turn
into storm clouds.

14. Fog
 A collection of water
droplets in the air on or
near the earths surface.
 It is a type of stratus cloud.
 The amount of fog depends
on the place because the
moisture that forms it is
created locally.

15. Cold cloud Precipitation

16. Warm Cloud precipitation

17. Rain and Snow

18. Sleet, Glaze, and Hail