Dr. Thomas Johnson is a hydrologist at the U.S. EPA Office of Research and Development. His research interests include assessing and managing the impacts of climate and land use change on water and watershed systems, stream-riparian interactions, resilient designs of urban and agricultural BMPs, decision support and modeling tools for local and regional and water management. Prior to joining the EPA he held positions with the Academy of Natural Sciences of Philadelphia, and was an American Association for the Advancement of Science (AAAS) Science and Technology Policy Fellow in Washington, DC. He has degrees from Penn State University (Ph.D.), Colorado State University (MS), and University of Colorado (BA).