The environmental movement, like most successful political activities in the United States, tries hard at, and is often rather successful at, concealing complex and troublesome facts from public view. Please don't take me for supporting unregulated Russian forestry or industrial pollution, but the notion of global warming centered on the North Pole is dated and contradictory to observations.
The complex and troublesome fact is that air pollution, especially burned sulfur, increases cloud brightness and frequency, thereby reflecting sunlight and at least partly countering the greenhouse effect of carbon dioxide, especially in the industrial northern hemisphere and the cloudy Arctic Ocean. Douglas Lilly, Norman, Okla.
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