My research in the area of organic geochemistry is focused on applications of analytical chemistry, isotope geochemistry, and molecular biology to biochemical oceanography and Earth history. The “how, when, and why” of microbial processes yield insight about environmental conditions on Earth today, in the past, and about potential human impacts on our future. My recent work has focused on the global carbon and nitrogen cycles, paleo-temperatures, and paleo-CO2 records.