Junior researcher Julia Gottschalk spent two years doing postdoctoral research in Bern. Now the German geoscientist is moving on to Columbia University of the City of New York. What she particularly valued at the Oeschger Centre? The inspiring discussions beyond the borders of her own discipline.
Who knows, maybe the academic globetrotter was influenced by the city where she got her start as a researcher. Already in the 19th century, Bremen had ties to shipping and overseas trade, and it’s still regarded as cosmopolitan. It was in Bremen that Julia Gottschalk earned her bachelor’s degree in Geosciences – including a one-year exchange at the State University of St. Petersburg (Russia) and the local Otto Schmidt Laboratory for Polar and Marine Research, when she also joined a research expedition to the Laptev Sea in the Arctic Ocean. While studying for her master’s degree in Marine Geosciences at the University of Bremen, she encountered topics that still have fascinate her today: the global carbon cycle, abrupt climate change, changes from glacial to interglacial climate periods, and climate models.
At the University of Cambridge (UK), Julia Gottschalk did her dissertation at the Godwin Laboratory for Palaeoclimate Research within a group dealing with climate change and the interaction between earth, ocean and atmosphere systems. The title of her dissertation was “The role of the Southern Ocean in millennial-scale atmospheric CO2 changes”. Incidentally, the dissertation was made possible thanks to a Gates Cambridge Scholarship from the Bill and Melinda Gates Foundation, which funds young researchers who not only excel academically, but who also work towards a better world and demonstrate leadership potential.
After that, Julia Gottschalk’s academic study-and-travel years brought her to Bern for a two-year postdoc term with the Oeschger Centre group for Paleoceanography and Marine Biogeochemistry. And now it’s already time to move on. The 31-year-old is trading the Swiss capital for New York – more specifically, the Lamont-Doherty Earth Observatory, part of Columbia University and less than an hour’s bus ride from Manhattan.
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.
But for the ambitious researcher, perhaps the biggest benefit at the Oeschger Centre would turn out to be something else: the intense discussions with climate modellers and researchers working on the reconstruction of atmospheric CO2 from ice cores. “I found this cooperation across disciplines very rewarding. Through the open exchange that’s maintained here, I’ve found access to a new research community, as well as to new, even unpublished insights,” notes Julia Gottschalk after two years in Bern.
For example, she was able to compare different climate models with the aid of her new contacts. “It became clear to me that to understand more, I generally needed to link the proxy data from marine sediment analysis to models.” One probably has to acknowledge that no model can provide a true reflection of the past, but they are nonetheless important as thought experiments and for testing important hypotheses. “Models, in all their varieties and complexities, can show that certain processes on Earth are physically possible, even if their realistic representation of the future and past Earth system needs to be critically assessed.”
In her career so far, Julia Gottschalk has continuously experienced the importance of collaborations in science and research – not least when it comes to having access to excellent sample material for her reconstructions. Those who don’t work at one of the few institutes that maintain the costly logistics and infrastructure for sea-going expeditions and sampling campaigns somewhat depend on collaborations. Thanks to her doctoral supervisor, Julia Gottschalk maintains such a collaboration to the Paleoceanography group of the Laboratory for Sciences of Climate and Environment at the University of Paris-Saclay, which carries out expeditions on the research vessel Marion Dufresne on a regular basis. “It’s a privilege to work with such high-quality and long sediment cores,” she says with gratitude.
It goes without saying that the postdoctoral fellow continues to use first-class sample material in the future. For her project at the Lamont-Doherty Earth Observatory, she not only armed with funding from the German Research Foundation (DFG), but also with new sediment cores from her colleagues from the Laboratory for Sciences of Climate and Environment and from the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven (Germany) to investigate carbon cycling in the Southern Ocean. The aim of the project is to understand what pathways carbon has taken to enter or leave the ocean during the last warm period (about 115,000 to 130,000 years ago), which is one key to understand the natural mechanisms of the demise of an climatic warm period. “We don’t know exactly how carbon cycling and the many controlling factors operate over short periods of time, such as over a thousand or even a hundred years,” says Julia Gottschalk. Now she wants to help close this knowledge gap with high-resolution paleoclimate reconstructions in the Southern Ocean. True to her motto, she points out that “the key to success is collaboration – for your personal career as well as for scientific progress”.