E
llen D. Williams, Ph.D.
Ellen Williams is a Distinguished University Professor Emerita and the recent Director of the Earth Systems Science Interdisciplinary Center (ESSIC) at the University of Maryland. She has been a member of the University of Maryland faculty since 1981, with a leave of absence from the University to work in industry and then in government from 2010-2017. Before returning to the University in January of 2017, she served as the Director of the Advanced Research Projects Agency, ARPA-E, which advances high-potential, high-impact energy technologies that are too early for private-sector investment.
Prior to Senate confirmation for her role in ARPA-E, Williams had been the Chief Scientist at BP (2010-2014), and a Distinguished University Professor in the Institute of Physical Science and Technology and the Department of Physics at the University of Maryland. At Maryland she established an internationally recognized research program in experimental surface science, exploring fundamental issues in statistical mechanics and nanotechnology. She founded and then led the University’s interdisciplinary Materials Research Science and Engineering Center from 1996 through 2009. After returning to campus in 2017, she worked with colleagues in the College of Engineering and the School of Public Policy to advance technical innovation in the development use of clean energy. At ESSIC, she was responsible for a collaborative (NASA, NOAA and UMD) program of research on the analysis and integration of data from earth-observing satellites, with application of the results to forecast changes in the global environment and associated regional implications. In 2024 she retired from her faculty position at Maryland, and remains affiliated as a Distinguished University Professor Emeritus. She continues to work on clean energy issues on advisory boards for the MIT Energy Initiative, Clean Energy Ventures, Climate Vault and the Global CO2 Initiative (U. of Michigan).
Williams is a member of the National Academy of Sciences, the American Academy of Arts and Sciences, a foreign member of the Royal Society (London), and a fellow of the American Association for the Advancement of Science. She has a distinguished history of professional service in clean energy and national security topics.

David M. Van Wie, Ph.D.