Lacustrine leaf wax hydrogen isotopes indicate strong regional climate feedbacks in Beringia since the last ice age
نویسندگان
چکیده
The Late-Quaternary climate of Beringia remains unresolved despite the region's role in modulating glacial-interglacial and as likely conduit for human dispersal into Americas. Here, we investigate Beringian temperature change using an ?32,000-year lacustrine record leaf wax hydrogen isotope ratios (?2Hwax) from Arctic Alaska. Based on Monte Carlo iterations accounting multiple sources uncertainty, reconstructed summertime temperatures were ?3 °C colder (range: ?8 to +3 °C) during Last Glacial Maximum (LGM; 21-25 ka) than pre-industrial era (PI; 2–0.1 ka). This ice-age summer cooling is substantially smaller other parts Arctic, reflecting altered atmospheric circulation increased continentality which weakened glacial region. Deglacial warming was punctuated by abrupt events that are largely synchronous with seen Greenland ice cores originate North Atlantic but also controlled locally, such opening Bering Strait between 13.4 11 ka. Our reconstruction, together modeling experiments, indicates responds more strongly freshwater forcing under modern-day, open-Bering conditions conditions. Furthermore, a 2 increase (Monte range: ?1 +5 over anthropogenic reverses 6 decline ?10 0 through Holocene, indicating recent Alaska has not surpassed peak Holocene warmth.
منابع مشابه
Leaf wax stable isotopes from Northern Tibetan Plateau: Implications for uplift and climate since 15 Ma
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ژورنال
عنوان ژورنال: Quaternary Science Reviews
سال: 2021
ISSN: ['1873-457X', '0277-3791']
DOI: https://doi.org/10.1016/j.quascirev.2021.107130