I use isotope geochemistry and numerical modeling to study the chemical reactions and physical processes regulating the carbon, alkalinity, and electron fluxes that keep Earth habitable. My PhD work focused on measuring river sulfate sulfur isotope ratios to constrain the role of sulfuric acid generation in reducing the drawdown of carbon dioxide from chemical weathering, both in individual catchments and globally. My future work will use multiple isotopic systems and intramolecular isotopic information, enabled by recent developments in mass spectrometry, to study Cenozoic cooling, the coevolution of the Phanerozoic biosphere with seawater chemistry, and Precambrian biogeochemical cycles.