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Air Masses

2. Air Masses Hot air rises Cold air sinks
Low pressure
Cold air sinks
High pressure
Differences in pressure causes wind

5. How Air Moves From poles towards equator 3 wind belts in north
3 wind belts in south

6. Coriolis effect – winds are deflected by Earth’s rotation

8. Formation of Air Masses
Air mass – large body of air in which temperature and humidity are similar
Stationary or slow

9. Form in:
Polar – cold and dry
Tropical ocean – warm and moist

10. Types of Air Masses Classified by source region
Temperature and humidity
Ocean – maritime
Land - continental

11. Continental Form over large land masses Humidity low, dry
Stay in location for days or weeks

12. cT – continental tropical
cP – continental polar
Cold and dry
cT – continental tropical
Warm and dry

13. Maritime Form over large bodies of water Higher humidity
Bring rain or fog

14. mP – maritime polar mT – maritime tropical Moist and cold
Moist and warm

15. North America Air Masses
Continental Polar
cP – cold and dry
From polar regions in Canada
Moves south-sotheast

16. From polar Pacific, polar Atlantic
Maritime Polar
mP – cold and moist
From polar Pacific, polar Atlantic
Moves southeast, southwest-south

17. Moves north-northeast
Continental Tropical
cT – warm and dry
From US southwest
Moves north-northeast

18. From tropical Pacific, tropical Atlantic
Maritime Tropical
mT – warm and moist
From tropical Pacific, tropical Atlantic
Moves northeast, north-northwest