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SPECIAL REPORT: Oxygen isotope composition of human tooth enamel from medieval Greenland: Linking climate and society

Because the oxygen isotope composition of mammalian tooth enamel (δ 18 O p ) can be used as a proxy for local surface temperature, teeth from archaeological sites can serve as records of climate change on the time scale of decades to thousands of years. Such records can be interpreted in terms of the response of human societies to climate change. In the first such study, the analyses of Norse and Inuit teeth from North Atlantic sites validate the relation between δ 18 O p and temperature. A 3% 0 decrease in δ 18 O p from sites in Greenland about A.D. 1400 to 1700 implies rapid cooling during the Little Ice Age.