Stergios Zarkogiannis

I am a marine scientist and I specialize in paleoceanography and marine micropaleontology. I am interested in pelagic calcification and the last years I have been working with planktonic foraminifera. I was intrigued by the fact that the cause behind their shell weight shifts during climatic cycles remains a mystery and so I focused on mechanisms that may drive plankton shell mass variations. From studying sediment cores, I found evidence that changes in foraminifera calcification intensities may be a buoyancy regulating mechanism for optimum habitat maintenance during glacial/interglacial ocean density changes. During my Newton Fellowship in Oxford with Ros Rickaby I aim to test my hypothesis on past extreme abrupt geological events, such as the sapropels, where the hydrological signal is momentarily deconvolved from the influence of seawater’s carbonate chemistry on pelagic calcification.