PP51C-1384 - The evolution of the Indian ocean sector of the Indo-Pacific Warm Pool over the last 0.5 Myr
Résumé
There is a dearth of long, highly resolved records that document the evolution of the Indian Ocean sector of the Indo-Pacific Warm Pool (IPWP) over the last several glacial-interglacial cycles. Here we present new geochemical records (δ13C, δ18O, Mg/Ca) that were measured at multi-centennial resolution through the last half a million years in both surface and thermocline dwelling planktic foraminifera from Integrated Ocean Drilling Program (IODP) Site U1443 (5°23.05’N, 90°21.67’E, 2,924 m water depth). The data document the hydrographic variability in the upper water column at a site that is located in the eastern Indian Ocean, within the core of the IPWP. We will discuss at the obliquity and precession bands the coherence and phase of the IODP Site U1443 time series relative to key climate variables, such as insolation, atmospheric greenhouse gas concentrations, ice volume, high latitude and global temperatures, and Asian Monsoon intensity. We will also evaluate the implications of our new results for our understanding of the orbital-scale variability of the IPWP.