Influences of Weather and Climate

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Radiation Noun

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[ray-dee-ay-shun]

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Radiation

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Energy that travels from a source in the form of electromagnetic waves, such as light and heat from the Sun.

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Example: The Sun sends energy to the Earth through space as radiation, which is a form of heat transfer.

Front

Convection Noun

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[kuhn-vek-shun]

Back

Convection

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The transfer of heat through the movement of a fluid, such as a liquid or a gas like air.

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Example: Heating a fluid like water causes the warmer, less dense part to rise and the cooler, denser part to sink, creating a circular flow.

Front

Convection Current Noun

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[kuhn-vek-shun kur-ent]

Back

Convection Current

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A circular flow in a fluid caused by the rising of warm, less dense fluid and sinking of cool, denser fluid.

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Example: This image shows a sea breeze, a type of convection current. The sun heats the land, causing warm air to rise and move away, while cooler, denser air from the sea moves in to take its place.

Front

Updraft Noun

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[up-draft]

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Updraft

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An upward current of air, typically caused by the rising of warm air within a convection current.

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Example: This diagram shows that when the ground is heated by the sun, the air above it gets warmer and rises, creating an updraft.

Front

Downdraft Noun

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[down-draft]

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Downdraft

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A downward current of air, typically caused by the sinking of cool, dense air within a convection current.

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Example: This diagram shows a column of air moving downwards, illustrated by the central red arrows. This sinking air is a downdraft, a key part of air circulation.

Front

Water Vapor Noun

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[wah-ter vay-per]

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Water Vapor

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The invisible, gaseous state of water that is present in the atmosphere after evaporation.

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Example: This image shows individual water molecules spread far apart and moving freely, which is how water exists as an invisible gas called water vapor.

Front

Evaporation Noun

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[ih-vap-uh-ray-shun]

Back

Evaporation

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The process by which a liquid, such as water, changes into a gas or vapor due to an increase in heat.

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Example: This diagram shows water (H2O) leaving a plant's leaf as vapor through tiny pores called stomata, a specific type of evaporation called transpiration.

Front

Condensation Noun

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[kon-den-say-shun]

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Condensation

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The process where water vapor in the air cools and changes back into liquid water droplets or solid ice crystals.

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Example: When warm, moist air comes into contact with a cold surface like glass, the water vapor in the air cools and turns into liquid water.

Front

Precipitation Noun

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[pri-sip-i-tay-shun]

Back

Precipitation

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Any form of water, such as rain, snow, sleet, or hail, that falls from clouds to the Earth's surface.

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Example: This image shows a cloud releasing both raindrops and a snowflake, representing the liquid and solid forms of precipitation that fall to Earth.

Front

Air Mass Noun

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[air mas]

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Air Mass

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A large body of air with relatively uniform temperature, humidity, and pressure throughout its volume.

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Example: This image shows a large body of cold air and a large body of warm air, which are two types of air masses, interacting.