"To put it simply during the rise of the Roman Empire (Roman Warming Period) there were no glaciers in Glacier National Park."

Skeptic's Corner: "...getting back to normal.”

Bryson mentions the retreat of Alpine glaciers, common grist for current headlines. “What do they find when the ice sheets retreat, in the Alps?”

We recall the two-year-old report saying a mature forest and agricultural water-management structures had been discovered emerging from the ice, seeing sunlight for the first time in thousands of years. Bryson interrupts excitedly.

“A silver mine! The guys had stacked up their tools because they were going to be back the next spring to mine more silver, only the snow never went,” he says. “There used to be less ice than now. It’s just getting back to normal.”
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To put it simply during the rise of the Roman Empire (Roman Warming Period) there were no glaciers in Glacier National Park.