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SCIENCE NOTES - WEATHER
LESSON 7 (Chapter 11)
How Do Air Masses Affect Weather?
- A large region of the atmosphere that has similar properties
throughout is called an air mass.
- Once an air mass is formed, it is moved by the global winds.
- When two air masses meet, they form a boundary called a front.
Fronts often cause unsettled weather and precipitation.
- Maritime polar – cool, moist air
- Maritime tropical – warm, moist air
- Continental polar – cold, dry air
- Continental tropical – hot, dry air
How Do Fronts Affect Weather?
- In a cold front, cold air moves in under a warm air mass. They
usually bring brief, heavy storms. After the cold front, it is usually
clear and colder.
- In a warm front, warm air move in over a cold air mass. Warm fronts
often bring light to steady precipitation (rain or snow) that may last for
days. After the warm front, it is usually warm and more humid.
- Air in a convection cell moves in a circular pattern due to unequal
heating and cooling.