1. ESB: Ch. 18 Study Guide Name: ______________________ Period: _____________________ Date: __________________
Sec 18.1: Water in the Atmosphere
Changes of State
1. Select the appropriate letter in the figure that identifies water’s changes of state:
_____ sublimation, _____deposition, _____condensation, _____ freezing, _____ evaporation, _____melting
2. Fill in the following table
Change Description Latent Heat
of State (absorbs, releases)
Evaporation
Condensation
Melting
Freezing
Sublimation
Deposition
Humidity: Match
_____ Humidity a. A device, consisting of two thermometers, that is used to calculate relative humidity.
b. A measure of humidity expressed as a temperature.
_____ Relative humidity
c. A ratio of air’s water vapor content compared to the amount it could possibly hold.
_____ Dew point d. Occurs when air holds all of the water vapor that it could possibly contain at a specific
temperature and pressure.
_____ Saturation
e. The term for water vapor in air.
_____ Psychrometer
Sec 18.2: Cloud Formation
3. Use the following words to fill in the blanks below: adiabatic cooling, clouds, condense, cools, saturated, warms
When air is allowed to expand, it ______________. When air is compressed it ______________. Rising air expands and cools (this is termed
____________________________). When the air reaches its dew point, it becomes ______________ and water droplets ______________ in the
air. These masses of water droplets are visible as ______________.
Use the figure to answer the following questions:
4. According to the figure, at what altitude does the wet adiabatic rate start?
5. What is the temperature of air near the surface?
6. At what temperature does the air release its moisture as condensation to
form clouds?
Processes that Lift Air
7. Matching:
_____ Orographic lifting a. Differences in reflectivity, e.g., asphalt road versus grassy field, create areas of warmer and
cooler air. Rising warm air creates clouds, sinking cool air is clear
_____ Frontal Wedging
b. Occurs when air comes together after moving from different directions and rises causing
_____ Convergence cloud formation cools adiabatically creating clouds and storms
c. Warm and cold air masses collide and warm air is forced up over the cooler air. The rising air
_____ Localized convective lifting
cools adiabatically creating clouds, precipitation, and storms
d. When air is forced up the sides of mountains, it rises creating clouds and precipitation

2. 8. Above the ground, tiny particles called ____________________ serve as surfaces for water vapor condensation.
Sec 18.3: Cloud Types and Precipitation
Cloud Classification
9. Clouds have ____________________ names and are classified according to their ____________________ and ____________________.
10. Matching:
_____ Alto a. High, white, and thin, resemble feathers or cotton candy. Made of ice crystals
b. Flat, layered, sheet-like clouds
_____ Cirrus
c. Prefix for clouds of middle height
_____ Cumulus d. Rounded, lumpy cloud masses, resemble cauliflower
e. Prefix for clouds that produce precipitation
_____ Fog
_____ Nimbo
_____ Stratus
11. Label the cloud photographs:
____________________ ____________________ ____________________
12. List five types of precipitation.