Aprroximately 1/3 of the terrestrial environment experiences seasonal snow cover. This  includes high latitudes with large soil carbon stores, terrestrial carbon sinks in mid lattitudes, and high elevations areas that are the primary water source for semi-arid regions.  Common to all these systems are widespread changes in both climate and land cover that alter the cycling of energy, water, carbon and nutrients.  Our work in seasonally snow covered systems identifies and addresses the considerable knowledge gaps associated with how these environments respond to disturbances ranging from climate and vegetation change to atmospheric deposition.