Early deglacial (~19-17 ka) strengthening of the Northeast monsoon
Earlier studies that mostly relied on bulk 14 C dating indicated a weaker Southwest monsoon (SWM) and a stronger than present Northeast monsoon (NEM) during the Last Glacial Maximum (LGM, ~18000 14 C years or ~21000 calendar years ago). We have analyzed a sediment core from the equatorial Indian Oce...
Main Authors: | , , , , |
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Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
American Geophysical Union
2005
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Subjects: | |
Online Access: | http://repository.ias.ac.in/49761/ http://www.agu.org/pubs/crossref/2005/2005GL024070.shtml |
Summary: | Earlier studies that mostly relied on bulk 14 C dating indicated a weaker Southwest monsoon (SWM) and a stronger than present Northeast monsoon (NEM) during the Last Glacial Maximum (LGM, ~18000 14 C years or ~21000 calendar years ago). We have analyzed a sediment core from the equatorial Indian Ocean, where planktonic foraminifera were dated by Accelerator Mass Spectrometry (AMS 14 C). δ 18 O analysis of three species of foraminifera viz. Globigerinoides ruber, Globigerinoides sacculifer, and Globorotalia menardii reveals that the NEM strengthened during the early deglacial period (~15000 14 C years ago or ~18000 calendar years ago) relative to the present and not during the LGM as surmised earlier. |
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