My research focuses primarily on the flow and evolution of ice sheets and glaciers. As noted in the most recent IPCC assessment, the single largest uncertainty in projections of sea-level rise over the coming century is due to our as yet inadequate models of cryospheric change, and particularly ice-sheet dynamics. This motivates a great deal of my research effort. More specifically I model the dynamics of ice streams (concentrated regions of fast-flowing ice), along with their floating extensions, called ice shelves. I am also interested in feedbacks between the atmosphere, ocean, and cryosphere, and therefore view the inclusion of dynamic cryospheric component models within earth system models as a priority.