Download weather and climate chapter 3 section 1 air masses

Latitude determines temperature
Moisture determined by whether it forms over oceans or
continents
12-7 What are air masses?
Lesson Review
PART A Write true if the statement is true. If the statement is false,
change the underlined term to make the statement true.
True 1. An air mass forms when air stays over an area for a while or
________
moves slowly over an area.
__________
F- Dry 2. Air masses that form over land are moist.
True
__________
3. Air masses that form over tropical regions are warm.
F- Cold 4. Polar air masses form over warm regions.
__________
True
__________
5. A warm air mass that forms over the Caribbean Sea is a
maritime tropical air mass.
______________
F- Continental 6. Air masses that form over dry land are tropical air
masses.
PART B Identify the air masses shown on the map. Write
your answer in the space with the same number as the box
on the map.
mP
mP
mT
cP
cT
mT
mP
1. _____________
cP
2. _____________
mP
3. ______________
mT
4. ______________
cT
5. ______________
mT
6. ______________
Skill Challenge
Skills: classifying, identifying
Complete the table.
Land
Water
Water
Land
Cold
Cold
Warm
Warm
Cold
Cold
Warm
Warm
Dry
Moist
Moist
Dry
Fronts – boundary between air masses where
precipitation is likely to occur
Cold FrontWedge of cold air dry air (cP) pushes
under a warm and humid air (mT). When
the boundary passes, temps drop and
pressure rises.
Cold dry air is denser, so it
wedges underneath the
warm air and easily wins
the battle. Cold fronts
move quickly.
Warm Front –
A warm humid air mass (mT) tries to push
over a cool drier air (cP or mP). When the
boundary passes, temps rise and pressure
falls.
Warm air is less dense than
cold air, so it cannot push
the cold air out of the easily.
It is forced up and over the
cold air mass. Warm fronts
move slowly.
Stationary Front
• A stationary front occurs when the air masses on
either side of the front are not moving toward each
other.
Occluded Front:
When a cold front catches up to a warm front.
High Pressure System (Anti-Cyclone)- bring fair
weather
Clear (sunny) conditions, low chance of
precipitation.
Winds circulate clockwise and outward
away from the center (N. Hemisphere)
Low Pressure System (Cyclone)- bring cloudy &
stormy weather
Clouds and high chances of precipitation.
Form along frontal boundaries.
Wind circulates counter-clockwise and
inward toward center. (N. Hemisphere)