Murray, a geomorphologist, studies how Earth-surface environments are shaped, and how they change over time, especially in response to changing forcing. He has addressed phenomena in desert, artic, alpine, and riverine environments, although most of his recent research focuses on coastal environments. Much of his research addresses couplings between physical and ecological processes, and couplings between natural and human dynamics. Murray approaches natural systems, and human/natural coupled systems, with the perspective and techniques developed in the study of nonlinear dynamics and complex systems, looking for possibly simple, emergent interactions that could explain apparently complicated behaviors. He develops and uses relatively simple, numerical models to test such hypotheses, and uses observations in developing hypotheses and testing models (using strategies and types of model predictions most effective for testing the usefulness of the type of model in question, in specific scientific contexts). Murray’s most recent research falls under three umbrellas, investigating: 1) how changes in the size and shape of river deltas can be driven by couplings between river processes, coastal processes, and sea-level rise, and by couplings between physical and ecological processes; 2) how coastlines (sandy and rocky) are shaped and reshaped over time, including the effects of changing storm climates; 3) how coastal barriers and back-barrier marshes and bays respond to changing rates of sea-level rise and storm impacts. Some of the research under each of these umbrellas addresses couplings between human actions and landscape/ecosystem evolution.