Foss Earth and Sun Investigation 3

Meteorologist

a scientist who studies the weather

Forecast

a prediction about what kind of weather to expect

Atmosphere

the gases surrounding the Earth

Weather variable

data that weather scientists measure

Pressure

the push when compressed air pushes back

Compress

to force air into a smaller space

Thermometer

a weather instrument that measures temperature in degree Celsuis

Hygrometer

a weather instrument that measures humidity in percent

Wind vane

a weather instrument that measures wind direction

Barometer

a weather instrument that measures air pressure in millibars

Troposphere

layer of Earth's atmosphere where most weather happens

Weather

the condition of the air around us

Nitrogen

the most plentiful gas in Earth's atmosphere

Oxygen

the second most plentiful gas in Earth's atmosphere

Air

the mixture of gases surrounding Earth

Air pressure

the force exerted on a surface by the mass of the air above it

humidity

water vapor in the air

mass

the amount of material in something

matter

anything that takes up space and has mass

precipitation

rain, snow, sleet or hail that falls to the ground

temperature

a measure of how hot the air is

visibility

the distance one can see through the air at ground level

wind

air in motion

wind speed

how fast the air is moving past an observation point

wind direction

the compass direction from which the wind is coming