Paul G. Richards

Paul Richards came to Columbia in 1971 as an assistant professor and had a full-time academic teaching career up until 2008. Since then, he has worked part-time as a “Special Research Scientist” and is currently the Principal Investigator on projects funded by U.S. government agencies.

In grad school, he studied elastic wave propagation, earthquake physics, and Earth structure. He was fortunate in 1975 to be asked by Kei Aki to co-author a textbook on Quantitative Seismology. The textbook has been translated into Russian, Chinese, and Japanese, is still in print, and has enabled many contacts around the world. His most exciting research was in 1996 when Xiaodong Song and he discovered seismological evidence that the solid inner core of the Earth, in recent decades, has rotated eastwards a few tenths of a degree per year with respect to the mantle and crust. The inner core is roughly the size of the Moon and sixty times nearer to us. For it to be moving at a rate perceptible on human time scales is remarkable. This work was described in a Jeffreys lecture given to the Royal Astronomical Society.

Prof. Richards chaired the Department of Geological Sciences at Columbia from 1979 to 1983, long before it became the Department of Earth and Environmental Sciences and part of the Earth Institute. In 1984, he took a national service leave from Columbia to work in Washington for twelve months and joined the unit that wrote President Reagan’s Report to the Congress on Soviet Noncompliance with Arms Control Agreements. It was fascinating in mid-career for him to begin interacting with worlds of which he had known very little—the military, the monitoring agencies, the labs that design and engineer nuclear weapons, the policy agencies, and people on Capitol Hill. He was asked to evaluate claims that the Soviet Union had carried out underground nuclear explosions with yields larger than the 150-kiloton limit specified by the bilateral Threshold Test Ban Treaty. Claims that the U.S.S.R. had tested up to the 400 to 600 kiloton level turned out to be invalid. He has a book chapter on part of this experience, published thirty years later, which delves into ethical issues arising in the development of policies that have a strong technical component.

In the mid-1990s, during the Clinton administration, he went back to Washington for another year’s national service leave from Columbia and became a small part of the large team that negotiated the Comprehensive Nuclear-Test-Ban Treaty—an experience that, for him, included formally presenting in Geneva the position of the United States, on ways to manage problems (under a ban on nuclear test explosions) associated with the conduct of large chemical explosions. Since returning to Columbia, he has maintained links with the U.S. Air Force, which leads U.S. efforts in monitoring compliance with nuclear test-ban treaties, with the U.S. Arms Control and Disarmament Agency, and then with the Bureau of Arms Control in the Department of State after the Clinton administration abolished U.S.A.C.D.A. in the late 1990s at the behest of Senator Jesse Helms. He has also worked with the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), which was established in 1996 with headquarters in Vienna, Austria. The CTBTO is an interim organization tasked with building up the verification regime of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) in preparation for the Treaty’s entry into force, as well as promoting the Treaty’s universality. It operates global networks to detect seismic, infrasound, and hydroacoustic signals and to collect radionuclides generated by processes of nuclear fission and fusion. This is a huge operation, requiring hundreds of millions of dollars per year, and is technically more complex than the support for any other arms control treaty, although it is comparable to efforts led by the International Atomic Energy Agency, which supports the Non-Proliferation Treaty. The CTBTO picks up signals from hundreds of earthquakes and chemical explosions every day and plays an important role in the entire process by which national and international agencies join in providing excellent capability to monitor nuclear test explosions. Paul Richards helped initiate international science conferences in Vienna for the CTBTO in 2006, which have been held every two years since 2009.

Prof. Richards began seismological research in 1965 with a mathematics background from the United Kingdom. As a grad student at the California Institute of Technology, he developed an interest primarily in the theory of seismic wave propagation and then in methods to understand how the recorded shapes of seismic waves are affected by processes of diffraction, attenuation, and scattering. However, over the years based in New York, his work became more and more practical and data-based. Since the 1990s, he has focused on the development of seismological methods to improve monitoring of both earthquakes and explosions. It is remarkable that for more than a hundred years, the main procedures for locating earthquakes and explosions, as used by agencies that publish the location of hundreds of seismic events each day, have seen very little change, even though detection today is far better than it used to be, and methods have become available to make location estimates with precision that is up to a thousand times better than those achieved via the traditional methods.

In 1987, Columbia University promoted Paul Richards to Mellon Professor of the Natural Sciences, a position funded by the Mellon Foundation to recognize an academic at Columbia who, in middle age, had made a career switch. In practice, he carried on with geophysics research but maintained connections with agencies involved in monitoring compliance with nuclear arms control treaties, specifically nuclear test bans. In 2003, he initiated an undergraduate science course at Columbia called “Weapons of Mass Destruction” that reviewed how these weapons work, what happens to their environment when they are used, how they are made and who has them, and the efforts that have been attempted to bring them under control.

His work has continued in geophysical research, but more and more he became involved with institutions outside academia. So in 2008, he gave up his professorship. He became a Special Research Scientist at Columbia, but is still able to write proposals and (sometimes) get them funded. Thus, he continues with research and keeps an office at Lamont, but is now freer to travel. He doesn’t sit on admissions committees and doesn’t have formal responsibility for teaching students, although he continued teaching the WMD course through 2013. The responsibility for this course, typically with more than a hundred students, now lies with the Department of Physics, and he gives guest lectures.

His career has been hugely aided by fellowships from the Sloan and Guggenheim Foundations in the 1970s and from the MacArthur Foundation for five years in the 1980s, which he greatly appreciates.

Outside his office and home, he is an organist and sings in various choirs, including the Oratorio Society of New York. However, he has given up sailing small boats and wind-surfing for tamer pursuits.


B.A. in Mathematics, 1965 – Peterhouse, University of Cambridge
M.S. in Geology, 1966 – California Institute of Technology
Ph.D. in Geophysics, 1970 – California Institute of Technology

Honors and Awards
  • Sloan Foundation Fellow (1973–1977) 
  • James B. Macelwane Award (1977, American Geophysical Union) 
  • Fellow of the American Geophysical Union (1977)
  • Guggenheim Foundation Fellow (1977–1978) 
  • MacArthur Foundation Fellow (1981–1986) 
  • Member, Council on Foreign Relations (since 1992) 
  • Fellow of the American Association for the Advancement of Science (1993) 
  • Phi Beta Kappa Visiting Scholar in 2000–2001 
  • Harold Jeffreys Lecturer, Royal Astronomical Society (March 1999) 
  • Leo Szilard Lectureship (2006, American Physical Society, for work on nuclear explosion monitoring) 
  • Fellow of the American Academy of Arts and Sciences (2008) 
  • Harry Fielding Reid Medalist of the Seismological Society of America for 2009 (awarded in 2010) 

Updated June 28, 2023