DOUBLING the amount of carbon dioxide in the air would warm the world by 4 Degree C, but halving it would affect the climate even more dramatically, say researchers at Yale University.
Robert Oglesby and Barry Saltzman calculate that low levels of carbon dioxide in the atmosphere were a key factor in triggering ice ages of the past. During the most recent ice age, there was as little as 180 parts per million by volume (ppm). The present concentration of carbon dioxide (CO
Oglesby and Saltzman used a computer model (a general circulation model), to investigate how changes in carbon dioxide concentration are likely to have influenced the climate. They calculated mean temperatures for a simulated Earth with 100, 200, 330, 460, 660 and 1000 ppm carbon dioxide in its atmosphere.
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