Solid waste: Any garbage or refuse, sludge from a wastewater treatment plant, water supply treatment plant, or air pollution control.

Melting: Becoming liquefied by heat.

Global warming: A gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, chlorofluorocarbons, and other pollutants.

Deforestation: The action of clearing a wide area of trees.

Greenhouse gas: A gas that contributes to the greenhouse effect by absorbing infrared radiation, e.g., carbon dioxide and chlorofluorocarbons.

Overfishing: Deplete the stock of fish in (a body of water) by too much fishing.

Endangered species: A species considered to be facing an extremely high risk of extinction in the wild.

Carbon dioxide (CO2): Carbon dioxide is a compound of carbon and oxygen that exists as a colorless gas under conditions of standard temperature and pressure.

Cutting: The action of cutting something.

Fossil fuels: A natural fuel such as coal or gas, formed in the geological past from the remains of living organisms.

Climate change: A change in global or regional climate patterns, in particular a change apparent from the mid to late 20th century onwards and attributed largely to the increased levels of atmospheric carbon dioxide produced by the use of f

Air pollution: The presence in or introduction into the air of a substance which has harmful or poisonous effects.

Frozen: Having turned into ice as a result of extreme cold.