In the geological past, there have been six major ice ages. During five of these six ice ages, the atmospheric carbon dioxide content was higher than at present. It is clear that the colorless, odorless, non-poisonous gas called carbon dioxide did not drive past climates. Carbon dioxide is plant food, not a pollutant.
Humans have adapted to live on ice sheets, deserts, mountains, tropics, and sea level. History shows that humans and other organisms have thrived in warm times and suffered in cold times.
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