Climate Change : Glossary

There are 65 documents in this section.

  • Methane

    3 November 2000

    A simple hydrocarbon gas (CH4) produced during the decomposition of organic material under anaerobic conditions. It is the main constituent of natural gas and therefore and important fuel.

  • OPEC

    3 November 2000

    Organisation of Petroleum Exporting Countries. A group of Middle Eastern, Asian, African and Latin American nations that includes the world's major petroleum producers and exporters. They came together in 1960, recognising the importance of oil as a source of future development, and with the intention of using their petroleum resources to advance their economic interests.

  • Petroleum

    3 November 2000

    A mixture of naturally occurring hydrocarbons, that may exist in a solid (e.g. bitumen), liquid (e.g. crude oil) or gaseous state (e.g. natural gas). It commonly contains variable amounts of other chemicals such as sulphur (S) and nitrogen (N). Petroleum is the end-product of the partial decay of living organisms which once inhabited the world's oceans. As they died they sank to the bottom of the oceans, where the anaerobic conditions allowed them to be preserved.

  • Environmental pollution

    22 August 2000

    The contamination of the physical and biological components of the earth/atmosphere system to such an extent that normal environmental processes are adversely affected.

  • Eutrophication

    22 August 2000

    The occurrence of high nutrient levels in freshwater and marine ecosystems, usually resulting in excessive plant growth and the death of animal and some plant life due to oxygen deprivation.

  • Fossil fuels

    22 August 2000

    Fuels such as coal, oil and gas made by decomposition of ancient animal and plant remains which give of carbon dioxide when burned.

  • Global warming

    22 August 2000

    The idea that increased greenhouse gases cause the Earth's temperature to rise globally.

  • Greenhouse effect

    22 August 2000

    The cause of global warming. Incoming solar radiation is transmitted by the atmosphere to the Earth's surface, which it warms. The energy is retransmitted as thermal radiation, but some of it is absorbed by molecules of greenhouse gases instead of being retransmitted out to space, causing the temperature of the atmosphere to rise. The name comes from the ability of greenhouse glass to transmit incoming solar radiation but retain some of the outgoing thermal radiation to warm the interior of the greenhouse. The 'natural' greenhouse effect is due to the greenhouse gases present for natural reasons, and is also observed for the neighbouring planets in the solar system. The 'enhanced' greenhouse effect is the added effect caused by the greenhouse gases present in the atmosphere due to human activities, such as burning of fossil fuels and deforestation.

  • Greenhouse gases

    22 August 2000

    Molecules in the Earth's atmosphere such a carbon dioxide (CO2), methane (CH4) and CFCs which warm the atmosphere because they absorb some of the thermal radiation emitted from the earth's surface.

  • Ozone hole

    22 August 2000

    A region of the atmosphere over Antarctica where, during spring in the southern hemisphere, about half the atmospheric ozone disappears. The Ozone layer protects the earth's surface from the effects of excess ultraviolet radiation. However, the growth in the volume and use of ozone-destroying chemicals, such as CFCs, has depleted the layer, allowing greater amounts of ultraviolet radiation to pass through to the earth's surface, raising fears of the increased occurrence of skin cancer, eye damage and genetic mutation in terrestrial organisms. (Recently scientists have decreases of 10-20 per cent in ozone over the Arctic).