The global ocean is a major sink of heat and carbon dioxide, considering the role of the ocean conveyor belt and associated biogeochemistry. Despite having the wealth of available palaeoceanographic data, it is a prerequisite to obtain the calibration of new proxies along with the traditional methods based on the microfossils. Such an approach will help in predicting the future climate projections of 2100, especially from the tropical and subtropical oceans, where temperature has already been reported to have increased by 1-2ºC as per the IPCC report. The microfossils, such as foraminifera, ostracods, diatoms, radiolarians, and others, are often employed to understand and/or test advanced geochemical techniques aimed at addressing questions regarding the past ocean-climate dynamics due to their excellent preservation potential. The proposed session will focus on inferring ocean temperature (surface, sub-surface, and bottom water), ocean circulation changes, carbonate system parameters such as pH and pCO2, primary productivity, and nutrient dynamics of the past. Such a comprehensive approach will help unravel the mechanisms of atmosphere-ocean interactions that influence the global climate system.