A new method of reconstructing biological activities
But why did Julia Gottschalk come to the Oeschger Centre in 2016? “For my dissertation, the leader of the Paleoceanography group, Samuel Jaccard, invited me to use a new method of reconstructing material fluxes in the ocean – something that had been newly established at the Institute of Geology at the University of Bern. This turned into a five-week research stay in Bern during my doctoral studies, which eventually led to a postdoc.” In a nutshell, the method used by the expert on ocean oxygenation changes, Samuel Jaccard, and his postdoctoral researcher works like this: uranium- and thorium-radioisotopes found in marine sediments track the vertical particle flux in the water column; it’s therefore possible to reconstruct the ocean’s past biological activities. And not just qualitatively, but quantitatively. “I was the first to test the new procedure along with doctoral students from Bern, and I was able to collect high-quality data,” says Julia Gottschalk. To finance the post-doctoral idea developed in Bern, Jaccard and Gottschalk managed to secure funds from the Swiss National Science Foundation (SNSF).
The prospect of being able to keep using the new methodological concept wasn’t the only thing that attracted the geoscientist to Bern. There, she also had access to highly specialized analytical technology, namely the MICADAS (MIni CArbon DAting System). This is a 14C dating device that can process extremely small material samples and that was set up at the Oeschger Centre in 2013, continuing the long history of 14C dating in Bern that began with the early career of Hans Oeschger himself.