Air MassesAir MassesWhat is an air mass?What is an air mass?

Air MassAir Mass

An An air massair mass is a large volume is a large volume of air defined by its of air defined by its temperature and water vapor temperature and water vapor content. content.

The weather characteristics The weather characteristics are determined by the are determined by the geographical origingeographical origin (Birth (Birth place) of the air mass. place) of the air mass.

Humidity- First Name Humidity- First Name

Air masses that form over the ocean are Air masses that form over the ocean are called called maritimemaritime air masses. air masses. They are MOIST (Maritime=Moist)They are MOIST (Maritime=Moist)

Air masses that form over the land are Air masses that form over the land are called called continentalcontinental air masses air masses They are dry (Continental=continent/land)They are dry (Continental=continent/land)

Temperature- Last NameTemperature- Last Name Air Masses that form near the Poles are known Air Masses that form near the Poles are known

as as polarpolar air masses. air masses. They are cold (Think Polar Bears!)They are cold (Think Polar Bears!)

Air Masses that form near the tropics are known Air Masses that form near the tropics are known as as tropicaltropical air masses. air masses. Tropical air is warm (Think tropical vacation!)Tropical air is warm (Think tropical vacation!)

Air Masses that form at the North Pole are Air Masses that form at the North Pole are known as an known as an arcticarctic air mass. air mass. (Arctic air is FREEZING)(Arctic air is FREEZING)

The name of an air mass has The name of an air mass has TWO TWO PARTSPARTS

The first part (first name) tells The first part (first name) tells us either maritime or us either maritime or continental. (humidity)continental. (humidity)

The second part (last name) The second part (last name) tells us tropical or arctic, polar. tells us tropical or arctic, polar. (temperature)(temperature)

Air MassAir Mass

First NameFirst Name Maritime (ocean)Maritime (ocean) Continental (land)Continental (land)

Last NameLast Name Arctic (freezing)Arctic (freezing) Polar (cold)Polar (cold) Tropical (warm)Tropical (warm)

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Key TermsKey Terms

Air mass- large area of air has the same Air mass- large area of air has the same temp and humidity (amount of moisture)temp and humidity (amount of moisture)

Continental air mass- Air mass over landContinental air mass- Air mass over land Maritime air mass- air mass over oceansMaritime air mass- air mass over oceans Polar air mass- air mass over cold regionsPolar air mass- air mass over cold regions Tropical air mass- air mass over warm Tropical air mass- air mass over warm

regionsregions Arctic air mass- air mass over the PolesArctic air mass- air mass over the Poles

What type of an air mass would it What type of an air mass would it be if…be if…

It started on land and near the North Pole?It started on land and near the North Pole? It started near the equator in Mexico?It started near the equator in Mexico? It started in Florida?It started in Florida? It started over the Atlantic Ocean in the It started over the Atlantic Ocean in the

North east?North east? It started near the South Pole over It started near the South Pole over

Antarctica?Antarctica? Can you make up a “What type Can you make up a “What type

question”????question”????

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