Catherine (Kate) Davis
Catherine (Kate) Davis is an Assistant Professor at North Carolina State University specializing in paleoceanography. Her research focuses on improving planktic foraminifera as proxies for reconstructing past ocean conditions. Kate integrates studies of living and fossil foraminifera with marine sediment records, to investigate low-oxygen environments, responses to rapid climate change, and foraminiferal ecology and paleoecology. She earned her PhD from the University of California, Davis, holds previous degrees from the University of Pennsylvania and the University of Bristol and conducted postdoctoral research at the University of South Carolina and Yale University. Passionate about understanding ocean-climate interactions, Kate employs diverse approaches and techniques with a dedication to advancing paleoceanography.
Further insights into shifts in glacial-scale oxygen change from multiproxy approaches
As Earth’s climate continues to warm, we are witnessing a dramatic decline in global ocean oxygenation. However the extent and pace of future deoxygenation remain uncertain. To better anticipate what's to come, we turn to the last deglaciation, the most recent interval of rapid warming. This period offers critical insight into how oceanic oxygen levels respond to major climatic shifts. We present records from two sites in the Eastern Pacific, one in the Equatorial Pacific and one along the Mexican Margin, within today’s most extensive Oxygen Minimum Zone (OMZ). At both sites, we document a shoaling and vertical restructuring of low-oxygen waters during the last deglaciation, consistent with patterns observed across the broader region. We reconstruct these vertical OMZ shifts in part by using the relative oxygen isotope composition of the OMZ-affiliated planktic foraminifer Globorotaloides hexagonus, a promising proxy for low-oxygen habitats.
These site-specific records contribute to a growing effort by the Past Ocean Oxygen (PO₂) working group, which is compiling a global synthesis of over 200 proxy records and model simulations from throughout the water column. This synthesis aims to quantify not just total oxygen changes between glacial and interglacial climates, but also the spatial and vertical patterns of deoxygenation that ultimately influence nutrient cycling, habitat extent, and ecosystem dynamics. This work seeks to move beyond questions of global oxygen inventory to identify where and how rapidly oxygenation is most vulnerable to change.
