I study the Earth's carbon cycle on timescales from 5 years to 100,000 years. My main interests are in:
1. fundamental mechanisms of the carbon cycle and
2. how humans are altering these mechanisms through combustion of fossil fuel, land use change, and erosion.
My research uses natural radiocarbon (14C, half-life 5730 years) coupled with organic geochemical tools like wet chemical extractions, 13C NMR, physical separations, chromatographic and spectroscopic studies to address problems related to carbon and climate. By combining geochemical tools with a chronometer (14C) I can answer questions about both mechanisms and timescales of carbon movement between reservoirs. I am particularly interested in problems related to the movement of carbon between fast and intermediate-cycling carbon pools, including the terrestrial biosphere, the atmosphere, rivers, and ocean sediments. New research in my lab includes the development of organic carbon oxidation state (Cox) as a tracer of Earth system processes.