Funktion und Aufgaben:
Investigating the timescales on which the silicate weathering feedback operates.
Have you ever wondered what the future trajectory of rising temperature and warming will be? Global warming events and their implications have been a subject of deep interest to mankind. However, the climate has evolved since the formation of the earth over billions of years. Earth has managed to maintain its habitability despite CO2 levels having reached a 1000 times more than today at various points in the past. How is this balance achieved? It's attained through the operation of the negative feedback known as the silicate weathering feedback which keeps a check on rising CO2 levels by the chemical weathering of silicate rocks and keeps the carbon cycle steady over long timescales. Even without human interference, this feedback would ultimately draw down the current carbon dioxide to bring atmospheric CO2 back to pre-industrial levels.This feedback has stabilized the climate in the past and can do so in the future as well. Studying the controls, timescale, and factors affecting the response of this feedback in the past would help us better foresee the fate of our planet. My research would study the behaviour of this feedback using a case study: MECO, a 40 Myr-old episode of gradual global warming in the Earth’s history. The puzzling behaviour of the feedback during this interval has thrown doubt on our understanding of the feedback, carbon cycle, and climate perturbations. To resolve these doubts, I will investigate what caused this unusual behaviour. What can alter the behaviour of the feedback on such short timescales? Can we increase the efficiency of the feedback on shorter timescales and remove CO2 from the ocean-atmosphere system at a much faster rate? I will investigate the above and more by combining different approaches from geochemistry, micropalaeontology, and geochemical modeling. Using the geochemistry of microscopic marine microfossils as a form of time machine. I aim to unravel these mysteries in the past and find the relevance for the future.
My project is funded by a DFG grant (HE 8660/3-1) awarded to Dr. Henehan along with the Co-Supervisors Prof. Dr.Blanckenburg, Dr. Frings.