Pam Vervoort
Pam Vervoort received her PhD from the University of California, Riverside where she developed an interest in the Earth system response to orbital forcing, particularly focussing on greenhouse climates with prevalent orbitally paced episodes of global warming. Using Earth system modelling, Pam quantifies the relative contribution of individual carbon cycle feedback processes and explore the importance of influencing factors such as paleogeography and background climate state. In late 2022, she moved to her current position as a research fellow, joining Dr. Sarah Green's research group at the University of Birmingham to investigate the evolution of carbon forcings and feedbacks across the Paleocene-Eocene Thermal Maximum.
Elucidating Signals in Deep Sea Sediment Records Using Earth System Models
Much of our understanding of Cenozoic carbon cycling and climate change relies on high-resolution proxy records from deep-sea sediments. These reveal the pervasive influence of astronomical forcing and indicate a strong link between climate and carbon cycle dynamics on tens to hundreds of thousand-year timescales. Deep-sea records also capture the intermittent presence of geologically rapid carbon release events, particularly during warm periods. Yet, uncertainties in the relative timing and magnitude of environmental change and external forcings (e.g. astronomical forcing or volcanism) complicate efforts to identify the mechanisms that drive or contribute to the perturbations. Further challenges arise from our incomplete understanding of feedbacks and the complex pathways through which climate signals are ultimately recorded in sedimentary records.
In this talk, I will show how Earth system models can help to refine interpretation of deep-sea proxy records. First, I simulate the effect of astronomical forcing on the Earth system and compare its expression in modelled paleoceanographic variables with available proxy records to identify factors and feedbacks that shape the global response. I will also highlight the spatial variability in modelled ocean signals and implications for interpreting records from individual sites. Constraints on the astronomically forced ‘background’ variability are also necessary to identify and interpret exceptional climate perturbations. Lastly, I will use simulations of the Paleocene-Eocene Thermal Maximum — the largest perturbation of the Cenozoic — to demonstrate the capability of Earth system models to quantify the total magnitude of carbon release events and assess the role of carbon cycle feedbacks.
