Chapter 18 Study Guide
Name_________________________________
Which gas is the most important for understanding
atmospheric pressure?
Water vapor
Rain, snow, sleet & hail are examples of?
Precipitation
_____________ can change from one state of
matter to another at the temperature and
pressures experienced at Earth’s surface.
Water
Water Vapor makes up __% of the atmosphere
0-4%
What is condensation?
Change of state from gas to liquid
What is evaporation?
Change of state from liquid to gas
What is the difference between sleet and glaze?
Sleet is freezing rain
Glaze is rain that freezes as soon as it
reaches the ground
What type of precipitation increase in size as they
circulate within the cloud by forming layers of ice?
Hail
What do we call the temperature air needs to be
cooled to reach saturation?
Dew point
List and describe the 4 processes that lift air.
Orographic lifting
Convergence, lifting results = cooling &
condensation.
Frontal wedging
Localized convective lifting
Which process of lifting air is associated with
mountains that act as barriers to wind that cause
rain shadow deserts??
Orographic lifting
Which of the following is NOT produced by
condensation? (dew, smog, clouds, fog)
Smog
Give examples of condensation nuclei.
Dust
Smoke
Salt
Which cloud type is described as sheets or layers
that cover most of the sky?
Stratus
Which cloud type consists of individual rounded
masses that look like cauliflower?
Cumulus
What term is used to describe clouds of middle
height?
Alto
What 2 characteristics classify clouds?
Shape & height
What term means “rainy cloud”?
Nimbus
Which clouds are often associated with thunder
& lightning?
cumulonimbus
What is fog?
A cloud with its base at or near the
ground; cloud
What type of cloud is associated with hail?
cumulonimbus
What are the 5 main types of precipitation?
Which type of precipitation are raindrops that are
super-cooled (below 0ºC) and turn to ice when
they impact the ground?
Water vapor is the source of all condensation and
____________________, which is any form of
water that falls from a cloud.
Rain
snow
Sleet
Hail
glaze
glaze
precipitation
What is a cumulonimbus cloud? What else can it be
called?
Large, tall, dark rain cloud
thunderhead
What are thermals? What process of lifting air is
associated with thermals?
For precipitation to form, cloud droplets must grow
in size roughly ________________ times.
What is temperature inversion?
Pocket of warm air; localized convective
lifting
1,000,000
Air temperature increases with height
Define relative humidity
Ratio of water vapor content to its
capacity to hold water vapor at the same
temperature
What type of precipitation CLOUD creates
infrequent light snow or drizzle?
cirrus
What is frontal wedging?
occurs when warm and cold air masses
meet (creating a weather front).
How do clouds form?
Must have saturated air (full of water
vapor) that is cooled to its dew point,
AND
the water vapor must have something to
condense around = Condensation Nuclei
(includes dust, smoke, and salt from sea
spray