What causes winds?€¦ · More of the sun’s direct rays hit the equator making the temperature...

What causes winds?

Air pressure is the measure of the force with which air molecules push on a surface

The air pressure is strongest in the Troposphere because of gravity

Wind is the movement of air.

Winds are caused by differences in air pressure. (Cause of Wind)

Winds move from areas of high (cold air) pressure to areas of low (warm air) pressure

Differences in air pressure is caused by differences in the temperature of the air-caused by unequal heating of the Earth

The Earth is unequally heat because it is titled on its axis. More of the sun’s direct rays hit the equator making the temperature at the equator warmer and the air less dense creating area of low pressure (L)

The tilt of the Earth on its axis causes seasons on the Earth

Explain how wind is created and

move using Tom and Jerry

Differences in air pressure are caused by unequal heating of the Earth.

Cool air has higher air pressure so it flows underneath (sinks) the warm, less dense air.

A. B. C.

Because the Earth is tilted on its axis, the equator receives more direct solar energy from the sun.

Air at the equator is warmer than any where else on Earth . This less dense warm air rises creating areas of Low Pressure (L)

At the poles, the air is colder and denser than surrounding air, so it sinks. Creating areas of high pressure (H)

Warm air causes areas of low pressure (L) because the air is less dense than the surrounding air and it rises

Sinking cold air causes high pressure (H) because sinking air presses down on the air beneath it.

The apparent curving of path of winds and ocean currents due to the Earth’s Rotation

Winds in the Northern Hemisphere curve east.

Winds in the Southern Hemisphere curve west

The combinations of convection cells and the Coriolis Effect produce patterns of air circulation called global winds

Winds that blow over short distances and are caused by unequal heating of Earth’s surface within a small area.

Sea Breeze – a wind that blows from an ocean or lake onto land.

Land Breeze – the flow of air from land to a body of water

https://www.youtube.com/watch?v=ZQV

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Sea Breeze and Land Breeze

http://www.classzone.com/books/earth_

science/terc/content/visualizations/es19

03/es1903page01.cfm?chapter_no=vis

ualization

A wind vanemeasures wind direction.

The name tells where the wind is coming from.

i.e. – north wind blows from the north to the south.

An

anemometermeasures wind speed.

Wind Direction

The name of a wind tells you where the wind is coming from

For example: A west wind comes from the west and blows toward the east

Wind direction is determined with a wind vane

The wind swings the wind vane so that one end points into the wind

The wind-chill factor is the increased cooling that a wind can bring.