Daniel Leathers' major research interests include understanding the role of snow cover in the global climate system; the influence of land-surface changes (natural and human induced) on regional climates; environmental monitoring; environmental policy and resource management; and sustainability of global systems, especially in the context of climate variation, climate change and land-surface surface changes. He is the co-director of the Delaware Environmental Observing System (DEOS), a support tool for decision makers involved in environmental policy and planning, natural resource management, emergency management, transportation and other activities throughout the Delmarva Peninsula.