AIR MASSES AND FRONTS

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AIR MASSES AND FRONTS

• Chapter 16 Section 2

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Air Masses

• An air mass is a large body of air that develops
  over a particular region.
• Warm air forms over tropical regions near the
  equator.
• T- Tropical
• Cold air forms over polar regions.
• P- Polar
• Wet air masses form over water
• m- maritime
• Dry air masses from over land.
• c- continental

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Air masses

• Moisture content is noted by the first letter.
• m maritime wet
• c continental dry
• Temperature is noted by the second letter.
• P polar cool
• T tropical - warm

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Air Masses

• mP- maritime polar air mass
• cP continental polar air mass
• mT maritime tropical air mass
• cT continental polar air mass

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Fronts

• A front is a boundary between air masses.
• Four types of fronts and map symbols
• Cold front
• Warm front
• Occluded front
• Stationary front

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COLD FRONT

• What is a cold front? A cold front forms when a
  cold air mass pushes under a warm air mass.
• Bring thunderstorms, rain or snow.
• This produces cumulonimbus clouds.
• Cold front followed by cooler drier air.

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WARM FRONT

• What is a warm front? A warm front forms when a
  warm air mass moves up and over a cold air mass.
• This produces stratus and cirrus clouds.
• Brings drizzly precipitation.
• Followed by clear warm weather.

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STATIONARY FRONT

• What is a stationary front? A stationary front
  forms when a warm air mass and a cold air mass
  meets but neither advances.
• Many days of cloudy, wet weather.

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OCCLUDED FRONT

• What is an occluded front? An occluded front
  forms when a fast moving cold air mass overtakes
  a slower warm air mass.
• Brings cool temperatures with large amounts of
  rain or snow

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Cold Front, Warm Front and Occluded Front
Animation

• http//www.3villagecsd.k12.ny.us/Murphy/medina/wea
  ther.html
• http//www.classzone.com/books/earth_science/terc/
  content/visualizations/es2002/es2002page01.cfm?cha
  pter_novisualization
• Click on the above links.

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Quiz Take this on the paper provided.

• 1. Describe a maritime polar (mP) air mass, in
  terms of moisture and temperature.
• 2. What is the name of an air mass that forms
  over water?
• 3. What is the name of an air mass that forms
  over land?
• 4. What is the name of an air mass that forms in
  a cold region?
• 5. What is the name of an air mass that forms in
  a warm region?
• 6. Describe a continental tropical (cT) air mass,
  Moisture and temperature.
• 7. The boundary between two air masses is called
  a ______________________.
• 8. A cold air mass meets and pushes a warm air
  mass out of the way.
• What type of front am I?
• 9. A warm air mass is trapped between to cold air
  masses.
• What type of front am I?
• 10. A warm air mass meets and pushes a cold air
  mass out of the way.
• What type of front am I?
• 11. I am a front that brings drizzly rain and am
  followed by warm clear weather. Name me
• 12. A cold air mass meets a warm air but neither
  is very strong. They are separated and many days
  of wet , cloudy weather occur.