Investigating Wind

Front

Air Pressure Noun

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[air presh-er]

Back

Air Pressure

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The force exerted onto a surface by the weight of the air above it, also known as atmospheric pressure.

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Example: This diagram shows that air pressure is highest at sea level and decreases as you go higher, because there is less air pushing down from above.

Front

Barometer Noun

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[buh-rom-i-ter]

Back

Barometer

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A scientific instrument used to measure atmospheric pressure in units such as millibars or inches of mercury.

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Example: This diagram shows how a barometer works: atmospheric pressure pushes down on the mercury in the dish, balancing the weight of the mercury inside the tube.

Front

Pressure Gradient Noun

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[presh-er grey-dee-ent]

Back

Pressure Gradient

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The rate of change in air pressure between two points in the atmosphere, which is the primary driver of wind.

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Example: This image shows how air pressure changes with height, creating a pressure gradient between the mountaintop (low pressure) and the ground (high pressure).

Front

Convection Cell Noun

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[kuhn-vek-shuhn sel]

Back

Convection Cell

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A circulatory pattern where warmer, less dense fluid rises and cooler, denser fluid sinks, transferring heat.

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Example: Heating water from below causes warmer water to rise and cooler water to sink, creating a circular flow called a convection cell.

Front

Coriolis Effect Noun

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[kor-ee-oh-lis uh-fekt]

Back

Coriolis Effect

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The apparent deflection of a moving object's path from a straight line, caused by the rotation of the Earth.

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Example: Due to the Earth's rotation, winds are deflected from a straight path, curving to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

Front

Anemometer Noun

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[an-uh-mom-i-ter]

Back

Anemometer

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A scientific instrument used for measuring the speed of the wind.

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Example: This image shows a simple anemometer made of cups that catch the wind, causing the device to spin to measure wind speed.

Front

Wind Vane Noun

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[wind veyn]

Back

Wind Vane

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A scientific instrument that shows the direction from which the wind is blowing.

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Example: This image shows a wind vane, a tool with a pointer that pivots to show the direction from which the wind is blowing.

Front

Sea Breeze Noun

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[see breez]

Back

Sea Breeze

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A local wind blowing from the sea toward the land during the day, caused by the land heating up faster.

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Example: This diagram shows how the sun heats land faster than the sea, causing cool, high-pressure air to move from the sea to the land.

Front

Land Breeze Noun

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[land breez]

Back

Land Breeze

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A local wind blowing from the land toward the sea at night, caused by the land cooling down faster.

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Example: At night, the land cools faster than the sea. This image shows cool air from the land moving out to sea, creating a land breeze.

Front

Hadley Cell Noun

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[had-lee sel]

Back

Hadley Cell

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A large-scale atmospheric convection cell in which air rises at the equator and sinks at medium latitudes.

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Example: This diagram shows how a Hadley cell works: warm, moist air rises at the Equator, cools down, and then sinks as cool, dry air.