Monsoon, Upwelling, Silicon and Carbon cycling: climate driven interplays in the Arabian Sea up to the last InTerglacial

ongoing

In the Arabian Sea, the South West Monsoon (SWM) is active during summer and drives the Somali-Arabian Upwelling System (SAUS). The SAUS brings cold, deep and nutrient-rich water masses to the Indian Ocean’s surface, fuelling siliceous microplankton or silicifiers. Silicifiers (mainly diatoms and radiolarians), are an important component of the soft tissue pump, a biological mechanism that lowers atmospheric CO2 concentrations. Despite the key role of this soft tissue pump in monitoring global climate and the socio-economic impacts of the SWM and SAUS in middle East and Eurasia, little is known about the monsoon, upwelling and soft tissue pump variability in strength relative to past climate and how they may evolve in the future due to global warming. To palliate this problem, MUSiC ArT proposes to use state-of-the-art technologies and methods to deconvolute the influence of climate on the SAUS and SWM intensity and associated-impacts on siliceous productivity over the last 150,000 years, covering the last interglacial period. The project aims to carry out innovative micropalaeontological and geochemical analyses on two sediment cores of the collections available at the Museum National d’Histoire Naturelle (MNHN, Paris, France). During the outgoing phase at GNS Science (New-Zealand), Artificial Intelligence and conventional microscopy will be used to generate census radiolarian and diatom counts. During a secondment at the University of Lausanne (Switzerland), isotopic ratios of 230Th and 232Th will be measured. For the return phase at the MNHN, diatom counts and high-quality imagery on microfossils will be completed and the isotope ratio of Silicon (δ30Si) and the Ge/Si ratio will be analysed on handpicked monospecific radiolarian and monogenus diatom samples. With this multidisciplinary approach, MUSiC ArT aims to couple AI, micropaleontology and geochemistry, advancing the Primary Investigator (PI)’s career by developing his unique researcher profile.