Robert G. M. SpencerRobert Spencer is Assistant Scientist at the Woods Hole Research Center, Massachusetts. He is an Earth system scientist whose research encompasses both aquatic geochemistry and biogeochemistry, predominantly focused on the carbon and nitrogen cycles.The majority of his research centers on the interface between the hydrosphere and biosphere over environmental timescales within natural systems. Spencer is a highly interdisciplinary scientist and uses a suite of analytical techniques to examine the influence of physical, chemical, and biological processes – especially watershed hydrology, ecosystem processing, global climate change, and land-use change – on the carbon and nitrogen cycles within aquatic and terrestrial environments. A major focus of Spencer's current research is examining controls on the export, processing, and fate of organic matter in the critical zone from the tropics to the Arctic, from soils and glaciers through rivers and estuaries and into the ocean. Spencer has utilized organic matter fluorescence extensively in this research for delineating sources and degradation histories of organic matter, as well as to improve resolution of components of the organic matter pool (e.g. dissolved organic carbon and biomarkers). Read More Read Less