Speleothem based 1000-year high resolution record of Indian monsoon variability during the last deglaciation

• Published in: Palaeogeography, palaeoclimatology, palaeoecology Vol. 395; pp. 1 - 8
• Main Authors: Lone, Mahjoor Ahmad, Ahmad, Syed Masood, Dung, Nguyen Chi, Shen, Chuan-Chou, Raza, Waseem, Kumar, Anil
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2014
• Subjects: Deglaciation; Indian summer monsoon; Southern India; Speleothem; Termination 1a; δ18O; Speleothem; δ18O; Southern India; Termination 1a; Deglaciation; Indian summer monsoon
• ISSN: 0031-0182; 1872-616X
• DOI: 10.1016/j.palaeo.2013.12.010

A high resolution record of the Indian summer monsoon (ISM) is generated using a δ18O time series from a stalagmite collected from the Valmiki cave in southern India. This record covers a time span of ~1000years from 15,700 to 14,700yr BP (before 1950AD) with an average sampling resolution of ~5years. High amplitude δ18O variation in this record reflects abrupt changes in ISM activity during the last deglaciation and suggest an age for the onset of Termination 1a (T1a) at ~14,800yr BP in the Indian sub-continent. This record shows evidence for strong changes in tropical climate during the last deglaciation. Coincident variability in VSPM4 δ18O with speleothems from southern China during Termination 1a suggests that these caves reflect fluctuations in ISM activity. The variance in δ18O amplitude reveals significant multidecadal variability in ISM activity. Our record reveals intervals of strong monsoon activity during the later phase of Heinrich event 1 (H1) and shows synchronous multidecadal variability between ISM and East Asian monsoon (EAM). Spectral analysis of δ18O time series in VSPM4 reveals solar forcing and strong ocean–atmospheric circulation control on ISM dynamics during the studied time interval. •First high resolution last deglacial ISM record from a South Indian speleothem•Decadal to multidecadal variability with abrupt changes in ISM activity•Strong solar and ocean–atmospheric control on Indian Summer Monsoon variability•South China caves influenced by Indian summer monsoon (ISM)•Timing of Termination 1a in Indian region and ISM relation with East Asian Monsoon