Much of my research focuses on documenting past changes in marine biologic productivity as a function of the glacial or interglacial mode of the earth's climate. Because the ocean is the single largest reservoir of carbon on the earth's surface, the physically- and biologically-mediated exchange of carbon between the ocean and the atmosphere has the capacity to significantly affect atmospheric concentrations of carbon dioxide, and thus climate. Over the past million years, the biologic sequestration of carbon in marine sediment has cycled largely in-step with glacial-interglacial stages of the earth's history, confirming a strong linkage between the marine biosphere, sedimentation, and climate variability. The challenge paleoceanographers face is unraveling the temporal leads and lags between the systems, and tracking the variability of each through time.
Related topics include chemically documenting geographic changes in the sources of wind-blown dust into the ocean. Such chemical changes can be related to variability in aridity of continental land masses, and changes in wind patterns, again as a function of the glacial or interglacial mode of Earth's climate. Research my group addresses these combined biologic- and wind-related paleoceanographic and paleoclimatologic issues in the equatorial Pacific Ocean, Caribbean Sea, Antarctic margin, and off the west coast of Africa.
