Climate Change : Glossary

There are 65 documents in this section.

  • Stewardship

    21 February 2001

    The attitude that human beings should see the Earth as a garden to be cultivated not a treasury to be raided.

  • Stratosphere

    21 February 2001

    Highly stratified and stable region of the atmosphere above the troposphere extending from about 10km to 50km.

  • Troposphere

    21 February 2001

    Lowest part of the atmosphere (from the earth's surface to about 10km in altitude at mid-latitudes, to about 9km altitude at high-latitudes and to about 6km altitude in the tropics) in which clouds and weather phenomena occur. The troposphere is defined as the region in which temperatures generally decrease with height.

  • Flood

    24 January 2001

    The inundation of normally dry land by water. Flooding causes millions of dollars'-worth of property damage and takes hundreds of lives each year. It is most common in river valleys or along the coastal areas of lakes, seas and oceans. River floods are caused when a river channel is incapable of carrying the volume of water added to it, and the excess spills over on to the adjacent floodplain. Heavy and prolonged precipitation, snowmelt, channel constrictions, dam failures and alterations to drainage basins may produce or contribute to flooding. Global warming through the increased melting of glaciers and ice sheets, and the subsequent rise in sea level, has the potential to increase the frequency and extent of coastal flooding.

  • Water vapour

    24 January 2001

    Water in its gaseous state, produced from liquid water by evaporation or by respiration from animals and transpiration from plants. Its presence in the atmosphere contributes to humidity and through subsequent condensation to precipitation. Water vapour is also a greenhouse gas.

  • Hydrological cycle

    8 December 2000

    The natural cycle by which water evaporates from the oceans and other water bodies, accumulates as water vapour in clouds, and returns to oceans and other water bodies as precipitation. Precipitation over land has two components: runoff and moisture from evapotranspiration.

  • Carbon dioxide (CO2)

    3 November 2000

    One of the major greenhouse gases. Human-generated carbon dioxide is caused mainly by the burning of fossil fuels.

  • Carbon tax

    3 November 2000

    A policy that would tax fossil fuels according to the amount of carbon they contained. This would reduce the demand for fossil fuels in general and cause a realignment away from coal to less polluting natural gas, or renewable sources of energy.

  • Coal

    3 November 2000

    A black or brown combustible material composed of carbon (C), various carbon compounds and other materials such as sulphur (S). The most abundant of the fossil fuels, it was formed through the accumulation of vegetable matter over millions of years in environments (e.g. swamps, deltas) which reduced the rate of decay of the organic material and allowed the preservation of the solar energy to absorbed by it when it was growing. When coal is burned, it is that energy which is released.

  • Fuel cells

    3 November 2000

    Fuel cells are electrochemical devices that convert a fuel's energy directly to electrical energy through a chemical reaction instead of combustion. Fuel cells operate much like continuous batteries when supplied with fuel to the anode (negative electrode). Fuel cells forego the traditional extraction of energy in the form of combustion heat, conversion of heat energy to mechanical energy (as with a turbine), and finally turning mechanical energy into electricity (e.g. using a dynamo). Instead, fuel cells chemically combine the molecules of a fuel and oxidizer without burning, dispensing with the inefficiencies and pollution of traditional combustion.