I specialize in the numerical modeling of atmospheres and oceans with particular emphasis on paleoclimate modeling. Ongoing research includes the use of a coupled atmosphere-ocean general circulation model to investigate the impact of orbital parameters on the coupled system, the maintenance of the equatorial thermocline, and the roles that such coupled phenomena as El Nino have played in the paleoclimates of Earth's history. Another area of interest includes the simulation of glaciation during periods of enhanced atmospheric carbon dioxide (such as the Ordovician) as well as during periods of reduced atmospheric carbon dioxide (such as the Last Glacial Maximum).