Palaeobiological evidence for Southern Hemisphere Younger Dryas and volcanogenic cold periods

• Main Author: Holdaway, Richard N.
• Format: Text
• Language: English
• Published: 2021
• Subjects: Antarctic; Moa; New Zealand; Takahe; The Antarctic; Antarc*; Antarctica
• Online Access: https://doi.org/10.5194/cp-2021-154; https://cp.copernicus.org/preprints/cp-2021-154/

Current consensus places a Southern Hemisphere post-glacial cooling episode earlier than the Younger Dryas in the Northern Hemisphere. New Zealand sequences of glacial moraines and speleothem isotopic data are generally interpreted as supporting the absence of a Southern Hemisphere Younger Dryas. Radiocarbon age series of habitat specialist moa (Aves: Dinornithiformes) show, however, that a sudden return to glacial climate in central New Zealand contemporary with the Younger Dryas. The cooling followed significant warming, not cooling, during the period of the Antarctic Cold Reversal. In addition, the moa sequence chronology also shows that the Oruanui (New Zealand) and Mt Takahe (Antarctica) volcanic eruptions were contemporary with abrupt cooling events in New Zealand. The independent high spatial and temporal resolution climate chronology reported here is contrary to an inter-hemispheric post-glacial climate see-saw model.