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I found myself thinking about climate change again today, as I enjoyed a scenic area in Maine where glaciers retreated 12,000 years ago. Simple logic for climate change says: you cannot explain current warming, if you cannot explain the onset and retreat of ice ages. We had what some call a mini-ice age several centuries ago, around the time the Spaniards came to the New World. That chill period gave way to a period of warming, still underway. Wouldn’t it be helpful to know why these cycles of warming and cooling occur, as we try to understand what is happening now?

That leads to analysis of earth’s orbit around the sun. If our earth’s orbit brings about marked seasonal changes we observe through one 365-day period, wouldn’t changes in earth’s orbit over millions of years affect cyclical phenomena such as ice ages?

Here’s an illustration of variation in earth’s orbit during a 100,000 year span:

The illustration is from an article titled, What Turns Ice Ages On… and Off?

This celestial jewel we live on is 4.54 billion years old, give or take 50 million years. Yet current theories about climate change – self-advertised as theories with political aims – rest on evidence from tree rings and computer models! I know climate scientists vary a lot in their ideas, as well as the evidence they use. Nevertheless, to read arguments about how ‘the science is settled’ for processes that have been under way for four and a half billion years, and for which we have the scantiest of evidence, seems absurd.

I would like to see even one climate scientist engaged in political controversy mention the coming and going of ice ages. Would that not impart a degree of reasonableness to the argument that has been hard to find?