Earth’s WeatherWeather Terms

CONDENSATION

Water CycleWater Cycle

Wat

er g

ets

into

the

atm

osph

ere

by:

EVAPORATION PRECIPITATION

COLLECTION

TRANSPIRATION

Water Cycle

Collection

Water gets into the atmosphere by:

transpiration and evaporation

• Precipitation• Collection

– Run-off– Groundwater

• Evapotranspiration– Evaporation– Transpiration

• Condensation

Water Cycle

collection

A measure of how fast air molecules are movingHIGH – molecules moving molecules

moving rapidly

LOW – molecules moving slowly

SCALE Freezing

Point

Boiling Point

Fahrenheit 32 212Celsius 0 100Kelvin 273 373

Temperature

Temperature Scales

Measurement of Water Vapor

Humidity - the amount of water vapor in the airTemperature affects how much moisture is in the air

Warmer air can hold MORE moisture – molecules are farther apart creating more space for the water molecules to fit in

Dew point – The temperature at which water vapor will condense

Relative Humidity – the amount of water vapor present compared to the amount that could be held at a specific temperature

AIR PRESSURE

Weight of air column

Warmer air is LESS DENSE – low pressure

Cooler air is MORE DENSE – high pressure

PRECIPITATION

RainRainliquid precipitationliquid precipitation

HailHailIce precipitation - ThunderstormsIce precipitation - Thunderstorms

Freezing rainFreezing rain Starts as snow, melts, then refreezes after passing Starts as snow, melts, then refreezes after passing through a THIN cold layer (freezes on contact w/ground)through a THIN cold layer (freezes on contact w/ground)

SleetSleetStarts as snow, melts, then refreezes before hitting the Starts as snow, melts, then refreezes before hitting the groundground

SnowSnowStarts out frozen and stays frozenStarts out frozen and stays frozen

cloud particles become too heavy to

cloud particles become too heavy to

remain suspended in the air

remain suspended in the air

Freezing Rain Sleet

Precipitation

Condensation Nuclei

The aerosol particle in the atmosphere around which a water droplet forms