Download Air Masses - Mr. Meyers Class

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AIR MASSES
Air Masses
 Hot air rises

Low pressure
 Cold air sinks

High pressure
 Differences in pressure
causes wind
How Air Moves
 From poles towards
equator
 3 wind belts in north
 3 wind belts in south
 Coriolis effect – winds
are deflected by Earth’s
rotation
Formation of Air Masses
 Air mass – large body of
air in which temperature
and humidity are similar
 Stationary or slow
 Form in:
 Polar – cold and dry
 Tropical ocean – warm
and moist
Types of Air Masses
 Classified by source
region
 Temperature and
humidity
 Ocean – maritime
 Land - continental
Continental
 Form over large land
masses
 Humidity low, dry
 Stay in location for days
or weeks
 cP – continental polar

Cold and dry
 cT – continental tropical

Warm and dry
Maritime
 Form over large bodies of
water
 Higher humidity
 Bring rain or fog
 mP – maritime polar

Moist and cold
 mT – maritime tropical

Moist and warm
North America Air Masses
 Continental Polar

cP – cold and dry
 From polar regions in
Canada
 Moves south-sotheast
 Maritime Polar

mP – cold and moist
 From polar Pacific, polar
Atlantic
 Moves southeast,
southwest-south
 Continental Tropical

cT – warm and dry
 From US southwest
 Moves north-northeast
 Maritime Tropical

mT – warm and moist
 From tropical Pacific,
tropical Atlantic
 Moves northeast, north-
northwest