Ellen Druffel is an explorer and scientific pioneer. Over her career, she has developed the measurement of radiocarbon ( 14C) as a tool for studying timescales of ocean carbon cycling. Her research has paralleled a technological revolution allowing a shift from detecting the occasional flash of radioactive decay in bulk samples to counting individual 14C atoms in single compounds extracted from water or sediments. In both cases, her laboratory’s meticulous attention to detail and development of new methods mean that Ellen’s results are not only trusted for their accuracy but often the first observations of their kind.
Ellen’s early work with Pete Williams at Scripps Institution of Oceanography required painstaking field and laboratory work to document profiles of radiocarbon in the open ocean, including both dissolved and particulate organic matter. Surprisingly, the mean radiocarbon age of dissolved organic carbon was thousands of years, even though its ultimate source is newly photosynthesized carbon. In attempting to explain this mystery, Ellen and her group have fundamentally altered our understanding of ocean organic matter through the recognition that dissolved and particulate matter consist of many distinct, differently aged components. Recent work investigates the roles of black carbon and recycling of sedimentary carbon in explaining old organic carbon.
Another of Ellen’s major contributions is the use of 14C in corals as recorders of past change in ocean ventilation and mixing. The amassed data from her global coral archive provide unique, continuous records of tropical ocean circulation and reveal temporal variations in phenomena such as the El Niño–Southern Oscillation over the past millennium. They also record patterns of uptake of bomb-produced radiocarbon in the surface oceans that constrain estimates of ocean-atmosphere exchange CO2 used in global climate models.
Ellen has made major contributions to AGU and its community through her leadership and deportment. Her sense of adventure has led her to explore the oceans, from scuba diving to ocean vessels and deep submersibles, and inspires a new generation of students. Her commitment to the advancement of oceanographic research and to forwarding women’s careers in science has impact far beyond her scientific discoveries.
As a longtime colleague in the Earth System Science Department at the University of California, Irvine, we salute Ellen as a kind and conscientious coworker with a wicked sense of humor. We think she is an adventurous, courageous researcher, like Roger Revelle, and are thrilled that she is this year’s Revelle Medal winner.
—Susan Trumbore, Max Planck Institute of Biogeochemistry, Jena, Germany; and Michael Prather, University of California, Irvine
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Dissolved organic carbon (DOC) in the global oceans is an important long‐term carbon sink. Connections between molecular size, reactivity, an...
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