Earlier studies that mostly relied on bulk 14C dating indicated a weaker Southwest monsoon (SWM) and a stronger than present Northeast monsoon (NEM) during the Last Glacial Maximum (LGM, ∼18000 14C 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 14C). δ18O 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 14C years ago or ∼18000 calendar years ago) relative to the present and not during the LGM as surmised earlier.
ASJC Scopus subject areas
- Earth and Planetary Sciences(all)