The Piora Oscillations are two cold periods in the Alpine climate history of the Holocene Epoch. Its dating differs between authors and no consistent modern approach currently exists. The spatial extent of the change is unclear; moreover, it does not show up as a major, or even identifiable, event in hemispheric temperature reconstructions.
The phenomenon is named after the Val Piora or Piora Valley in Switzerland, where it was first detected; some of the most dramatic evidence of the Piora Oscillation comes from the region of the Alps.[1]
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