A scientist who does not deny climate change insists that we are verging on hysteria about it. Even the Arctic shifts have been seen before:

We are told that the melting of the arctic ice will be a disaster. But during the famous medieval warming period--A.D. 750 to 1230 or so--the Vikings found the warmer northern climate to their advantage.

Emmanuel Le Roy Ladurie addressed this in his book "Times of Feast, Times of Famine: A History of Climate Since the Year 1000," perhaps the greatest book about climate change before the onset of modern concerns with global warming. He wrote that Erik the Red "took advantage of a sea relatively free of ice to sail due west from Iceland to reach Greenland. . . . Two and a half centuries later, at the height of the climatic and demographic fortunes of the northern settlers, a bishopric of Greenland was founded at Gardar in 1126."

Ladurie pointed out that "it is reasonable to think of the Vikings as unconsciously taking advantage of this [referring to the warming of the Middle Ages] to colonize the most northern and inclement of their conquests, Iceland and Greenland." Good thing that Erik the Red didn't have Al Gore or his climatologists as his advisers.

This is not an argument against moving toward non-carbon energy. That's worth doing anyway. It's an argument for a little more calm.

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