The 2015 William F. Brace Lecture "The Inference Spiral of Earthquake System Science" presented by Thomas Jordan: Looking back at a special EAPS event.
Earthquake system science is improving predictive models of fault rupture and seismic wave propagation through a development cycle that includes model formulation and verification, simulation-based prediction, validation against observations, and data assimilation. This inference spiral has increased the computational demands of earthquake system science more rapidly than Moore’s law, taxing the capabilities of the largest supercomputers.
In his March 2, 2015, lecture, Thomas H. Jordan, highlighted efforts to develop and validate earthquake forecasting models based on the coupling of rupture and ground-motion simulators, focusing on how we can use this modeling framework to pose interesting questions of contingent predictability as physics problems in a system-specific context.
More accurate earthquake simulations using realistic 3D crustal models can reduce the residual variance of the strong-motion predictions by a factor of two relative to the empirical models in current use, which could improve the estimation of exceedance probabilities at high hazard levels by an order of magnitude. These advances would have a broad impact on the prioritization and economic costs of risk-reduction strategies.
Thomas H. Jordan is a University Professor and the W. M. Keck Foundation Professor of Earth Sciences at the University of Southern California. His current research is focused on system-level models of earthquake processes, earthquake forecasting, continental structure and dynamics, and full-3D waveform tomography. As the director of the Southern California Earthquake Center (SCEC), he coordinates an international research program in earthquake system science that involves over 600 scientists at more than 60 universities and research organizations.
He is a member of the California Earthquake Prediction Evaluation Council and Past-President of the Seismological Society of America. He has served on the Council of the National Academy of Sciences (2006-2009) and the Governing Board of the National Research Council (2008-2011), and he was appointed by the Italian government to chair the International Commission on Earthquake Forecasting for Civil Protection following the 2009 L’Aquila earthquake. He is an author of more than 230 scientific publications, including two popular textbooks (with J. Grotzinger) Understanding Earth, 6th ed. and The Essential Earth, 2nd ed. He chaired the National Research Council panels that produced two decadal reports, Living on an Active Earth: Perspectives on Earthquake Science (2003) and Basic Research Opportunities in Earth Sciences (2002).
Jordan received his Ph.D. from the California Institute of Technology in 1972 and taught at Princeton University and the Scripps Institution of Oceanography before joining the Massachusetts Institute of Technology in 1984. He was head of MIT’s Department of Earth, Atmospheric and Planetary Sciences from 1988 to 1998. He has received the Macelwane and Lehmann Medals of the American Geophysical Union, the Woollard Award and President’s Medal of the Geological Society of America, and the 2012 Award for Outstanding Contribution to Public Understanding of the Geosciences by the American Geosciences Institute. He is a member of the National Academy of Sciences, the American Academy of Arts and Sciences, and the American Philosophical Society.
The William F. Brace Memorial Lecture Series
Bill Brace matriculated at MIT in 1943, earned a PhD (from Course XII) in 1953, and retired in 1988. During these 45 years he left the Institute only for short periods of time, for instance for duty in the Navy, a postdoctoral fellowship at Harvard, and a sabbatical or two. Bill Brace was Department Head from 1981 to 1988. Among his many accomplishments in this role was the merger in 1983 of Course XII (Earth and Planetary Sciences) with Course XIX (Meteorology and Physical Oceanography) to form the Department of Earth, Atmospheric, and Planetary Sciences (EAPS) as we know it today. During this tenure he recruited many faculty members who all became leaders of their fields — including Brian Evans, John Grotzinger (the inaugural Brace Lecturer), Kip Hodges, Tom Jordan, Marcia McNutt, Dan Rothman, Wiki Royden, and Jack Wisdom. Furthermore, he initiated the Thursday faculty meetings with free lunch, a tradition that we still enjoy today and which has become a core place for interaction of the faculty, lecturers, and senior research staff.
This series was established to honor Bill Brace's deep and lasting legacy as the first Head of EAPS, and its speakers will reflect the full disciplinary diversity of the Department.
The William F Brace Lecture is an annual all-department event with the speaker nomination/selection process handled by the Department Lecture Series Committee.