In the 19th century, an awareness began to dawn that accumulated carbon dioxide in the Earth’s atmosphere could create a “greenhouse effect” and increase the temperature of the planet. A perceptible process in that direction had already begun — a side-effect of the industrial age and its production of carbon dioxide and other such “greenhouse gases.”
By the middle of the 20th century, it was becoming clear that human action had significantly increased the production of these gases, and the process of “global warming” was accelerating. Today, nearly all scientists agree that we must stop and reverse this process now — or face a devastating cascade of natural disasters that will change life on earth as we know it.
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