Low-latitude glacial cooling in the Southern Hemisphere from amino-acid racemization in emu eggshells
Article Abstract:
The amino acid racemization of eggshells, when used as terrestrial fossil materials, can be relied on for data on archaeological sites beyond the range of radiocarbon dating. The temperature-dependent amino acid racemization reaction in radiocarbon-dated emu eggshell fragments from Australia were studied to reconstruct low-altitude subtropical temperatures for the past 45,000 calendar years before present (kyr BP). Racemization rate-changes suggest that millenial-scale average air temperatures were at least 9 degrees Celsius lower between 45 and 16 kyr BP than since 16 kyr BP.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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A glimpse of the glacial
Article Abstract:
A simplified coupled ocean-atmosphere climate model has been used to analyze the climate during the Last Glacial Maximum (LGM). The findings were largely consistent with what is already known about the LGM through data from marine sediments, tree rings, polar and tropical ice cores and groundwater. It was established that, during the LGM, the oceanic meridional heat flux in the Atlantic was very different from present conditions. This goes against recent assumptions used for atmosphere-only models.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1998
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Glacial-interglacial changes in ocean surface conditions in the Southern Hemisphere
Article Abstract:
A deuterium-excess history has been obtained from ice cores from Vostok, East Antarctica, covering the glacial-interglacial cycle of the past 150,000 years. A strong anticorrelation with the orbital obliquity of the Earth was found and values are higher during the cold stage 5d, possibly driven by relatively less moisture from high latitudes and more from low latitudes. The deuterium-excess is thus able to give long-term, spatially integrated data on ocean surface conditions.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1999
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