Air Masses What is an air mass Air

Air Masses What is an air mass?

Air Mass ØAn air mass is a large volume of air defined by its temperature and water vapor content. ØThe weather characteristics are determined by the geographical origin (Birth place) of the air mass.

Humidity- First Name Ø Air masses that form over the ocean are called maritime air masses. l They are MOIST (Maritime=Moist) Ø Air masses that form over the land are called continental air masses l They are dry (Continental=continent/land)

Temperature- Last Name Ø Air Masses that form near the Poles are known as polar air masses. l Ø Air Masses that form near the tropics are known as tropical air masses. l Ø They are cold (Think Polar Bears!) Tropical air is warm (Think tropical vacation!) Air Masses that form at the North Pole are known as an arctic air mass. Ø (Arctic air is FREEZING)

The name of an air mass has TWO PARTS ØThe first part (first name) tells us either maritime or continental. (humidity) ØThe second part (last name) tells us tropical or arctic, polar. (temperature)

Air Mass Ø First Name l l Maritime (ocean) Continental (land) Ø Last Name l l l Arctic (freezing) Polar (cold) Tropical (warm) http: //video. about. com/weather/Types-of-Air-Masses. htm

Key Terms Ø Air mass- large area of air has the same temp and humidity (amount of moisture) Ø Continental air mass- Air mass over land Ø Maritime air mass- air mass over oceans Ø Polar air mass- air mass over cold regions Ø Tropical air mass- air mass over warm regions Ø Arctic air mass- air mass over the Poles

What type of an air mass would it be if… Ø It started on land near the North Pole? Ø It started near the equator in Mexico? Ø It started in Florida? Ø It started over the Atlantic Ocean in the North east? Ø It started near the South Pole over Antarctica? Ø Can you make up a “What type question”? ?

http: //usatoday 30. usatoday. com/weather/tg/wamsorce. htm