Abstract
We investigated the variations in thermocline depth using the difference in \(\delta ^{18}\hbox {Oc}\) values between the two species of planktonic foraminifera, surface dwelling Globigerinoides ruber (s.s.) and thermocline dwelling Neogloboqudrina dutertrei, covering a time span of 9–23 kyr from the sediment core SK218/1 from the western Bay of Bengal (BoB). Here we show that during the strong phase of the Indian summer monsoon (12–9 kyr), a strong stratification leads to a shallow mixed layer and thermocline depth in the BoB as evident from higher \(\Delta \delta ^{18}\hbox {O}\) between the mixed layer and thermocline dwelling planktonic foraminifera species. Thus, a strong coupling between the Indian summer monsoon and thermocline depth in the BoB prevailed at a millennial time scale.
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We thank the director, NIO, for his encouragement and support. Anita Garg was responsible for the IRMS measurements. Jayu Narvekar assisted with the figures. The NIO contribution number is No. 6306.
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Naik, S.S., Naidu, P.D. Coupling of thermocline depth and strength of the Indian, summer monsoon during deglaciation. J Earth Syst Sci 128, 90 (2019). https://doi.org/10.1007/s12040-019-1132-7
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DOI: https://doi.org/10.1007/s12040-019-1132-7