Air Masses

EQ: How do meteorologists use air masses and weather fronts to predict our weather?

http://www.weatherquestions.com/What_is_an_air_mass.htm

Warm Up

Think back to the recent snow storm we had where we were out of school for one week.

Which type of air mass do you think caused the snow and why do you think this way?

• http://www.weatherquestions.com/What_is_an_air_mass.htm

An air mass is a large body of air with similar temperature, pressure, and humidity levels throughout.

Air Masses

• Get their properties from spending many days, even weeks, over the same area.

– Example: If an air mass sits over an ocean for awhile, it becomes humid.

– If an air mass sits over land, it becomes dry.

Air Masses

• Four types of air masses– Maritime– Continental– Polar– Tropical

Air Masses

Continental Maritime• Form over land and are dry • Form over water and are

moist

Air Masses

Tropical• Form over the tropics (low

latitudes)• Warm/Hot

Polar• Form at the polar regions of

Earth (high latitudes)• Cool/Cold

Air masses

Why does our weather change?

Air masses move!

How?

Global winds push air masses around the Earth!

Air MassesReflect

• M- Describe the four types of air masses.• I- If you could become an air mass, which

would you be and why? • U- Look back at the warm up question. Do

you agree with your answer? Support your answer with details.

• S- Create a flag for an air mass and explain why you chose that air mass.

Fronts• A front is a place where two different air masses

meet • Three main types• A “battle” between air masses

Continental Polar

Maritime Tropical

FRONT

Cold Fronts

• Click for Animation

Cold Front

• Moves quickly and can produce thunderstorms

• After it moves through, skies will be clear and temperatures will be cooler

Cold FrontReflect

• M- Explain the types of weather associated with a cold front.

• I- Act out a cold front with a partner.• U- A cold front passed through last night.

Predict what the weather is like now?• S- Create a metaphor: A cold front is like a _______________________. Explain.

Warm Front

• Click for Animation

Warm Front

• Moves slower than cold fronts• Brings humid weather and sometimes rains

for days

• After it moves through, temperatures are warmer

Warm FrontReflect

• M- Restate the cause of a warm front.• I- Which type of front do you feel is the best

and why?• U- Compare and contrast warm fronts and

cold fronts. • S- What would it be like to be a warm front?

Stationary Front

• Click for Animation

Stationary Fronts

• Two air masses next to each other, but neither moves.

• Weather remains the same for days

Stationary FrontReflect

• M- Summarize the three types of fronts.• I- You are charged with studying the effects of

air masses and fronts. How would you do it?• U-Which type of front do you think is the most

destructive and why?• S- Imagine you live in a world with only two

types of air masses. How would that effect fronts?

Become the meteorologist!

Use the weather map given to you and what you have learned about air masses and fronts and predict the weather for _______, _______,________,_______. Be sure to include an appropriate temperature and sky conditions (cloudy, sunny, raining, snowing, etc.)