Air Masses and Fronts Chapter 16 section 2

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Air Masses and FrontsChapter 16 section 2

• S6E4.b Relate unequal heating of land and water
  surfaces to form large global wind systems and
  weather.
• S6E4.c Relate how moisture evaporating from the
  oceans affects the weather patterns and the
  weather events such as hurricanes.

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Air Masses

• Air mass is a large body of air where
  temperature and moisture content are similar
  throughout.
• Moisture content and temp are determined by the
  area over which the air mass forms called source
  regions.
• Represented on maps by two-letter symbols first
  letter moisture content, second letter -
  temperature

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Air Mass Abbreviations

• cP Continental Polar
• means over land and DRY COLD
• cT Continental Tropical
• Over land and DRY WARM

• mP Maritime Polar
• Over water and HUMID COLD
• mT Maritime Tropical
• Over Water and HUMID WARM

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• c- Continental forms over land dry
• m- Maritime forms over water wet
• p- Polar forms over the Polar regions cold
• t- Tropical forms over the Tropics warm

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Cold Air Masses (3)

• Continental polar (cP)-

• From Northern Canada
• Brings extreme cold temperatures
• Brings cool, dry summers

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Cold Air Masses

• Forms over North Pacific or North Atlantic Ocean
• Cool and wet
• Rainy Snowy in the winter
• Cool Foggy in the summer

• Maritime polar (mP)
• (Forms in 2 places)

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Warm Air Masses (4)

• Maritime tropical (mT)

• Forms over Pacific, Atlantic, and Gulf of Mexico
• Winter they bring mild, often cloudy weather
• Summer, hot and humid weather, hurricanes, and
  thunderstorms.

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Warm Air Masses

• Continental tropical (cT)

• Forms over the deserts of northern Mexico US
• Moves northward and brings clear, dry, and hot
  weather.

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Air Masses of North America
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Review

1. What are the major air masses that influence the
   weather in the United States?
2. What is one source region of a maritime polar air
   mass?

1. Continental polar, maritime polar, maritime
   tropical, and continental tropical.
2. The North Pacific and the North Atlantic Oceans.

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Review

• 3. Why does the Pacific Coast have cool, wet
  winters and warm, dry summers?

• 3. Cool, wet winters are affected by a maritime
  polar air mass. Summers are affected by a dry
  continental air mass.