MeteorologyMeteorology

Air Masses, Fronts, and WeatherAir Masses, Fronts, and Weather

What is an air mass?What is an air mass?

10.10. Air mass Air mass- A large region of the - A large region of the atmosphere where the air has similar atmosphere where the air has similar properties throughout.properties throughout.

Air masses get their properties from the Air masses get their properties from the region over which it forms. region over which it forms.

– For example, air over the Gulf of Mexico is For example, air over the Gulf of Mexico is above warm water so the water warms the air. above warm water so the water warms the air.

When air masses move they bring these When air masses move they bring these conditions with them. conditions with them.

How do these air masses move?How do these air masses move?

Air masses are moved by global winds that Air masses are moved by global winds that tend to move from west to east. tend to move from west to east.

Between 30° North Latitude and 60° North Between 30° North Latitude and 60° North Latitude is the zone of Latitude is the zone of westerly windswesterly winds. . Westerly winds blow from the west. Westerly winds blow from the west.

What are lines of latitude? Who can show What are lines of latitude? Who can show me on the globe?me on the globe?

What happens if two air masses What happens if two air masses collide?collide?

When air masses of different temperatures When air masses of different temperatures meet they do not mix together. meet they do not mix together.

These air masses form a boundary between These air masses form a boundary between them called a front. them called a front.

Fronts often cause rainy, unsettled weather.Fronts often cause rainy, unsettled weather.

5.5. Weather Weather changes often occur at changes often occur at frontsfronts where different air masses meet where different air masses meet

Cold FrontsCold Fronts

Cold air moves in under a Cold air moves in under a warm air mass.warm air mass.

They often bring storms They often bring storms including thunderstorms including thunderstorms and strong winds.and strong winds.

After the storm clears the After the storm clears the skies are clear and the skies are clear and the weather is cooler and weather is cooler and drier. drier.

Warm FrontsWarm Fronts

Warm air moves in Warm air moves in over a cold air mass.over a cold air mass.

They often bring light, They often bring light, steady rain or snow. steady rain or snow. They may also cause They may also cause fog.fog.

After the weather is After the weather is usually warmer. usually warmer.

VIDEOVIDEO

Why are weather satellites so Why are weather satellites so important?important?

Satellites in space allow us to see fronts and Satellites in space allow us to see fronts and storms. storms.

These satellites orbit the Earth and take These satellites orbit the Earth and take pictures of weather patterns. pictures of weather patterns.

When fronts collide, scientists can see When fronts collide, scientists can see places where the weather may change places where the weather may change quickly and dangerously. quickly and dangerously.

Why is it so important that scientists are Why is it so important that scientists are able to predict what the weather is going to able to predict what the weather is going to be?be?