Chapter 23 Section 2 Review Page 586 #‘s 1-6 “Clouds and Fog”

1. Describe the conditions that are necessary for clouds to form. You need particulates (dust, pollen, etc.) with water vapor and a temperature below the dew point so that the air is saturated and clouds can form.

Cloud Formation

2. Explain the four processes of cooling that can lead to cloud formation. Adiabatic cooling: rising and expansion of an air mass Mixing: mixing of moist air with another air mass of different temperature Lifting: forced upward movement of air as it moves up a mountain Advective cooling: an air mass moving over a cooler surface (land or water)

Adiabatic cooling Lifting air masses

Advective cooling in Draper/Sandy

3. Compare cirrus, cumulus, and stratus clouds. Cirrus: wispy, high-altitude clouds composed of ice crystals Cumulus: puffy, vertically growing clouds, usually associated with fair weather Stratus: layered and form when warm moist air lies above a layer of cooler air

4. Compare clouds with fog. Both form as a result of condensation of water vapor in the air Fog occurs near the surface of Earth Clouds occur at higher altitudes

CLOUDS FOG

5. Describe four ways in which fog can form. Radiation fog occurs as a result of the nightly cooling when a layer of air is in contact with the cold ground Advection fog occurs when warm, moist air moves across a cold surface, like when moist ocean air flows over land

Radiation Fog

Advection Fog

5. Describe four ways in which fog can form. (continued) Upland fog forms when moist air rises over a slope Steam fog forms where cool air moves over a warm body of water

Upland fog Steam fog over California beach

6. Explain why air expands when it rises. When air rises it enters an area of lower pressure. The lower air pressure allows the air molecules to move farther apart (expand).

Rising, Expanding Air

The End…..(what is it?) An Aurora…..