The sun's energy affects all of Earth's spheres. Photo courtesy of dsevilla/Flickr.

Albedo: the percentage of solar radiation reflected back into space

Absorbed Energy: energy from the sun that is absorbed by materials and converted to heat energy (e.g. pavement absorbs a lot of the sun's energy)

Biomass Fuels: fuels that come from living (or once living) organisms

Fuel: anything that can be consumed and used as a source of energy

Reflected Energy: when the sun's energy is bounced back from the surface of a material (e.g. a mirror or ice reflects a lot of the sun's energy)

Transmitted Energy: when the sun's energy is able to pass through a material (e.g. glass transmits the sun's energy)

Air Mass: large body of air that has the same properties as the surface over which it develops

Albedo: fraction of solar radiation that is reflected back to space

Anemometer: instrument used to measure wind speed

Antarctic Circle: located at 66.5 ºS latitude

Arctic Circle: located at 66.5 ºN latitude

Barometer: instrument used to measure air pressure

Climate: average weather of an area over a period of 30+ years

Climatologist: scientist that studies climate

Dew Point: temperature to which air must be cooled to be saturated

Front: boundary between 2 air masses

Greenhouse Effect: natural warming of the atmosphere that occurs when certain gases absorb re-emitted radiation

Greenhouse Gases: atmospheric gases that contribute to Earth's greenhouse effect; include carbon dioxide, methane, water vapor, and nitrogen oxides

Global Warming: global rise in temperatures, caused primarily by an enhancement of Earth's natural greenhouse effect
Humidity: the amount of water vapor held in the air

Hurricanes: tropical, cyclonic storms that produce winds that travel at 120-240 km per hour

Hygrometer: instrument used to measure humidity

North Pole: located at 90 ºN latitude

Precipitation: water falling from clouds

Relative Humidity: percentage of moisture in the air

Revolution: amount of time it takes Earth to complete one trip around the sun; 365 days

Rotation: amount of time it takes Earth to complete one spin on its axis; 24 hours

Saturated: when air contains as much moisture as it can possibly hold; relative humidity is 100%

South Pole: located at 90 ºS latitude

Supercells: most powerful thunderstorms; required for tornado formation

Tropic of Cancer: located at 23.5 ºN latitude

Tropic of Capricorn: located at 23.5 ºS latitude

Vortices: spinning columns of air

Weather: describes present state of the atmosphere and current conditions.