Clouds and Fog

1
Clouds and Fog

• Section 24.2

2
Cloud Formation

• Clouds result from the condensation of water
  vapor in the atmosphere
• Suspended particles of ice, slat, dust, etc,
  provide the surfaces necessary for the
  cloud-forming condensation. These particles are
  called condensation nuclei.

3
Adiabatic Temperature Changes

• Are changes in temperature that result from the
  expansion or compression of air
• For dry air, temperature of dry air decreases
  about 1C for every 100 m
• For moist air it varies from 0.5C to 0.7C per
  100m

4
Condensation Level

• When the air reaches a level where its
  temperature is lower than its dew point, the
  moisture in the air condenses to form a cloud

5
Forceful Lifting

• Air can be forced up quickly when it encounters a
  mountain range
• During storms, warm air is pushed above denser
  cooler air

6
Classification of Clouds

• Clouds are classified by their form and altitude
• Low clouds up to 2000 m
• middle clouds -2000-6000 m
• high clouds above 6000 m

7
Stratus clouds

• Sheetlike, layered clouds. These are the most
  extensive clouds in the sky.
• Little rain usually falls from these kinds of
  clouds
• Varieties nimbostratus, altostruatus

8
Cumulus
9
Cumulus CLouds
10
Cirrus Clouds