I use stable and radiogenic isotopes to understand Earth system history. These studies examine the link between climate, tectonics, biological, and surface processes. Projects include: 1) examining the terrestrial climate history of the Earth focusing on periods of time in the past that had CO 2-levels similar to the present and to future projections; and 2) addressing how the chemical weathering of the Earth's crust affects both the long- and short-term carbon cycle. Field areas for these studies are in the Cascades, Rocky Mountains, Sierra Nevada, the European Alps, Tibet and the Himalaya and the Southern Alps of New Zealand.
I teach courses at the undergraduate and graduate level in isotope biogeochemistry, Earth system history, and the relationship between climate, surface processes and tectonics. I also teach a three-week field course each September in the Wind River Mountains of Wyoming for sophomores and GES majors. This course covers topics in environmental and geological sciences.
Editor American Journal of Science; Co-Director Stanford Stable Isotope Biogeochemistry Laboratory (present);Chair, Department of Geological and Environmental Sciences (2004-07); Co-Director Stanford/USGS SHRIMP Ion microprobe facility (2001-04)