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Episode 1: Origins
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		The earth. So far we know of only one planet like it. It has oceans and it has an atmosphere. It has a system to regulate surface temperature, a complex thermostat Ed Carmack says... employing ocean currents, clouds, wind, rain and its own rotation to distribute heat, and to maintain a balance in incoming solar and outgoing heat radiation. These variables all interact to ensure the planet is warm enough to sustain life and cool enough that the sun doesn't scorch the surface. Ice keeps the poles of the earth cold by reflecting sunlight, but the ice also constantlymelts, adding freshwater to the Ken Denman says... ocean, altering salinity and feeding currents that redistribute solar heat from the equator to the poles. Water evaporates from oceans and lakes and puddles, making storms that transport moisture over land, and clouds that trap heat close to the earth and return cold water to the surface as precipitation.			The average of all these variables, over time, is what we call "climate". It's a miraculous system of feedbacks Humfrey Melling says... so intricate that it is nearly impossible to study all the interactions at any one point in time, or to predict with any detailed accuracy much beyond a few days. Without these interactions the earth would be inhospitable to life. One of the most elegant phenomena governing Earth's climate is the greenhouse effect, first described by the French mathematician Fourier in 1827. He compared trace gases in the atmosphere to the glass panes on a Andrew Weaver says... greenhouse, allowing solar rays through but absorbing most of the longer waves of heat radiating back into space. Scientists estimate that without these greenhouse gases, and water vapour which makes clouds, the earth would be 33 degrees Celsius colder on average, frozen like the moon.

The following voices (and more) are featured in Origins, Episode One of the ClimateWatch audio series

ClimateWatch is a series of audio documentaries and public service messages about Earth's atmosphere, climate change and global warming. This five CD set is available to university, community, public and commercial radio stations, and to educational and academic users. Follow the Orders link. Home | Origins | Change | Impacts | Action | Voices | Lexicon | Orders | Links | Contact us Thursday, March 6, 2003 Copyright © 2003 ClimateWatch.net, Earth Chronicle Productions