I have investigated the connection between comprehensive climate models' internal variability and their sensitivity, which could provide a new "emergent constraint" on Earth's sensitivity. A point of emphasis in this work is studying models' behavior on different frequencies, which is relevant for future climate changes as well as for understanding past variations of Earth's climate.
A number of the most pressing questions in climate science concern the behavior of the tropics. Max Popp and I proposed a new set of indicators for tropical precipitation, with the aim of helping clarify the "double-ITCZ" problem in climate models. I am currently working with Tim Cronin to better understand the behavior of tropical low clouds in warmer climates, as well as to constrain some of the processes which determine tropical precipitation rates.
Outside of the tropics, the dynamics of the troposphere can be separated into the problem of the zonally-symmetric circulation and the problem of the zonally-asymmetric circulation. I have worked on both problems using a variety of idealized models, like the Phillips 2-layer quasi-geostrophic model and the GFDL dry dynamical core; with a particular focus being connecting the models' internal variability to their linear responses. Where possible I have compared my results with observational data.