IndSo

In the IndSO project, we propose to document the modes of variability of the ocean surface and the Indian Ocean thermocline in a synoptic manner during several contrasting climatic periods (glacial/interglacial) by developing an original approach based on the high-throughput analysis of planktonic foraminiferal faunas.

The contribution of high-throughput analysis with the MiSo prototype, which was developed at CEREGE and enables high-throughput imaging of sediments, offers the prospect of greater robustness than individual isotope analysis of foraminifera (IFA), with between 2,000 and 20,000 individuals analysed for each sample.

The key point we wish to address is to characterise the interannual variability of the surface hydrology of the Indian Ocean using a new high-throughput approach to analysing planktonic foraminifera faunas. We will test two hypotheses on the link between the mean state of the Indian Ocean and climate variability:

. Can El Niño-type variability be detected in the Indian Ocean during the last ice age? - Our data will help to validate this hypothesis by providing an integrated approach to the entire Indian Basin and not just the Indonesian margin.

. Can a signature similar to the IOD be detected during the warm interglacial periods of the Pleistocene? If so, is it comparable to the IOD intensification signal detected in coral sequences over the recent period?