Dr. Williams is a professor of earth system science within Clark’s School of Geography and is director of the environmental sciences program at Clark.  His expertise is in terrestrial ecosystems, global environmental change, and climate change.   He and his team engage in foundational research science on the climate impacts of forests.  By combining state-of-the-art satellite remote sensing with big data geo-computation, the lab is quantifying the carbon emissions avoided by protecting forests, the removals of carbon with forest growth, and also the important climate impacts of changing surface reflectivity (albedo) that happens with changes in tree cover.  Their work is informing decision makers about where we get the greatest climate benefit from retaining and expanding tree cover, worldwide.  The team is delivering action-ready datasets to land managers and policymakers working around the world, including The Nature Conservancy, the Open Space Institute, The Trust for Public Lands, and states participating in the U.S. Climate Alliance.  At Clark, in addition to teaching and mentoring students at all levels, he has served as vice chair of the faculty, chair of the graduate board, co-chair of the provost search, among other roles.  Externally, he has served as co-chair of the science leadership group of the North American Carbon Program, science co-investigator of the Harvard Forest National Science Foundation Long Term Ecological Research program, and science team member of NASA’s Carbon Monitoring System.