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Science and Development Network
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Definitions
Below is a directory of terms used in the field of climate change. Most of the definitions have been taken from the United States Environmental Protection Agency, with a few from the Intergovernmental Panel on Climate Change (IPCC), and the European Commission.
Climate change is the greatest challenge facing the world today. Long-term development planning must now include measures to deal with it.
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General Circulation Model (GCM)
A global, three-dimensional computer model of the climate system that can be used to simulate human-induced climate change. GCMs are highly complex, and represent the effects of such factors as reflective and absorptive properties of atmospheric water vapour, greenhouse gas concentrations, clouds, annual and daily solar heating, ocean temperatures and ice boundaries. The most recent GCMs include global representations of the atmosphere, oceans, and land surface.
Global Environment Facility (GEF)
A global, three-dimensional computer model of the climate system that can be used to simulate human-induced climate change. GCMs are highly complex, and represent the effects of such factors as reflective and absorptive properties of atmospheric water vapour, greenhouse gas concentrations, clouds, annual and daily solar heating, ocean temperatures and ice boundaries. The most recent GCMs include global representations of the atmosphere, oceans, and land surface.
Global Warming
An increase in the near-surface temperature of the Earth. Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases. Scientists generally agree that the Earth's surface has warmed by about 1 degree Fahrenheit in the past 140 years. The Intergovernmental Panel on Climate Change recently concluded that increased concentrations of greenhouse gases are causing an increase in the Earth's surface temperature and that increased concentrations of sulphate aerosols have led to relative cooling in some regions, generally over and downwind of heavily industrialised areas.
Greenhouse Effect
The effect produced as greenhouse gases allow incoming solar radiation to pass through the Earth's atmosphere, but prevent most of the outgoing infra-red radiation from the surface and lower atmosphere from escaping into outer space. This process occurs naturally and has kept the Earth's temperature about 59 degrees Fahrenheit warmer than it would otherwise be. Current life on Earth could not be sustained without the natural greenhouse effect.
Greenhouse Gas
Any gas that absorbs infra-red radiation in the atmosphere. Greenhouse gases include water vapour, carbon dioxide, methane, nitrous oxide, halogenated fluorocarbons, ozone, perfluorinated carbons, and hydrofluorocarbons.
Group of 77 (and China)
Main negotiating group of developing countries within the UN system. Its seeks to harmonise the negotiating positions of more than 130 developing-country members.
