Glossary 335Daisyworld A model of biological feedback mechanisms developed by James
Lovelock (see alsoGaia hypothesis)
DC Developing country – also Third World country
Deforestation Cutting down forests; one of the causes of the enhanced
greenhouse effect, not only when the wood is burned or decomposes, releasing
carbon dioxide, but also because the trees previously took carbon dioxide from
theatmospherein the process of photosynthesis
Deuterium Heavyisotopeof hydrogen
Drylands Areas of the world where precipitation is low and where rainfall often
consists of small, erratic, short, high-intensity storms
Ecosystem A distinct system of interdependent plants and animals, together with
their physical environment
El Ni ̃no A pattern of ocean surface temperature in the Pacific off the coast of
South America, which has a large influence on worldclimate
Electron Negatively charged component of theatom
Element Any substance that cannot be separated by chemical means into two or
more simpler substances
Environmental refugees People forced to leave their homes because of
environmental factors such as drought, floods, sea level rise
EU European Union
Evaporation The process of changing state from liquid to gas
FAO The United Nations Food and Agriculture Organization
Feedbacks Factors which tend to increase the rate of a process (positive
feedbacks) or decrease it (negative feedbacks), and are themselves affected in
such a way as to continue the feedback process. One example of a positive
feedback is snow falling on the Earth’s surface, which gives a highalbedo
level. The high level of reflected rather than absorbed solar radiation will make
the Earth’s surface colder than it would otherwise have been. This will
encourage more snow to fall, and so the process continues
Fossil fuels Fuels such as coal, oil and gas made by decomposition of ancient
animal and plant remains which give offcarbon dioxidewhen burned
FSU Countries of the former Soviet Union
Gaia hypothesis The idea, developed by James Lovelock, that thebiosphereis an
entity capable of keeping the planet healthy by controlling the physical and
chemical environment
Geoengineering Artificial modification of the environment to counteractglobal
warming
Geothermal energy Energy obtained by the transfer of heat to the surface of the
Earth from layers deep down in the Earth’s crust
Global warming The idea that increasedgreenhouse gasescause the Earth’s
temperature to rise globally (seegreenhouse effect)
Green Revolution Development of new strains of many crops in the 1960s which
increased food production dramatically
Greenhouse effect The cause ofglobal warming. Incomingsolar radiationis
transmitted by theatmosphereto the Earth’s surface, which it warms. The
energy is retransmitted asthermal radiation, but some of it is absorbed by