| A | B |
| non-renewable resource | a resource that cannot be replaced after it is used |
| greenhouse gases | gases in an atmosphere and absorb and emit radiation |
| food miles | the distance food travels from where it is grown to where it is ultimately purchased or consumed by the end user |
| fossil fuel | a fuel that is formed over many years from the remains of living organisms |
| solar energy | a sustainable energy that comes from the sun and can be collected in many ways |
| sustainable energy | an energy source that can be continually used and will not run out |
| wind energy | a sustainable energy from the wind collected from wind turbines |
| tidal energy | energy collected moving water from tides, rivers, and open ocean currents |
| geothermal energy | energy used from inside the earth |
| hydroelectricity | electricity generated from controlling water by using a dam |
| hydrogen | a fuel that can be made by splitting hydrogen atoms from water |
| renewable resource | a resource that can be replaced within a reasonably short time |
| biomass | burning of carbons such as corn or soy grown to make ethanol fuel |
| sustainability | to endure and maintain over time |
| carbon footprint | the greenhouse gases emitted directly and indirectly from a source |
| carbon cycle | a complex series of processes in which carbon is exchanged within the earth’s surroundings |