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.
In the 600-year long Roman Warming, it was 4ºC warmer than now. Sea level did not rise and ice sheets did not disappear. The Dark Ages followed, and starvation, disease, and depopulation occurred. The Medieval Warming followed the Dark Ages, and for 400 years it was 5ºC warmer. Sea level did not rise and the ice sheets remained. The Medieval Warming was followed by the Little Ice Age, which finished in 1850. It is absolutely no surprise that temperature increased after a cold period.
Unless I have missed something, I am not aware of heavy industry, coal-fired power stations, or SUVs in the 1,000 years of Roman and Medieval Warmings. These natural warmings are a dreadful nuisance for climate alarmists because they suggest that the warming since 1850 may be natural and may not be related to carbon dioxide emissions.
There was warming from 1860 to 1880, 1910 to 1940, and 1976 to 1998, with intervening periods of cooling. The only time when temperature rise paralleled carbon dioxide emissions was 1976-1998. The other warmings and coolings in the last 150 years were unrelated to carbon dioxide emissions.
Something is seriously wrong. To argue that humans change climate requires abandoning all we know about history, archaeology, geology, astronomy, and solar physics. This is exactly what has been done.
The answer to this enigma was revealed last week. It is fraud.