A letter to the editor on May 31 contained the following false statements that should be explained: “when the next ice age arrives” and that “humans survived several ice ages already”. We are currently in an ice age which started about 2 million years ago. When the planet has polar ice, it is in an ice age. We are now in an “inter-glacial period”, i.e. the time between glaciers. Humans were still in trees when this ice age began so humans have not survived “several” ice ages. We are experiencing our first and only ice age.
This inter-glacial period started 13,000 years when Montreal was still under 3 kilometres of ice. It will continue for another 50-70,000 years when the glaciers will return. As the ice started melting, humans learned agriculture. They could not do much agriculture during the glacial period. Scientifically knowledgeable humans have never lived through an inter-glacial period. Likely the Earth tends to warm for the first half of the inter-glacial period and then cools for the second half. This means that we may be looking at another 20,000 years of naturally warming temperatures, regardless of what humans do.
The world was much warmer 1,000 years ago than today. The Vikings sailed to America and grew crops in Greenland but they had to abandon North America and Greenland when the climate turned much colder. Indeed, Europe went into a “mini-ice age” during the Middle Ages. These are all well-known facts.
The world is getting warmer. We don’t know how warm it will get in an inter-glacial period. While our computer models cannot accurately predict long-range weather, environmentalists and politicians believe that humans can control the weather with a carbon tax and shutting down most industry on the planet. If they are wrong about humans causing this or wrong about our ability to control the weather, the policies proposed may be the costliest mistake in political and economic history.