The virtual seminar will be held from 12:30 to 2:00 p.m. (E.T.)
Nuclear test explosions occurred about once a week for forty years, beginning in 1945, and then slowed, and were restricted in various ways under a series of treaties beginning in 1963 and then banned under the 1996 Comprehensive Test Ban Treaty, which is not yet in force. Throughout this time advancements in instrumentation and computational techniques have radically improved capabilities in monitoring for nuclear testing. There also have been episodic disputes about treaty violations, the most recent instance was on 6 February 2026 when the United States accused China of conducting a nuclear test on 22 June 2020 that was not in compliance with the CTBT. This presentation will review some highlights of the efforts to monitor nuclear testing, and what happens when policy makers disagree with or are hostile to a conclusion strongly held by the technical community and seek to make up their own reality. It also will show advancements in monitoring since 1996, highlight specific areas for continued progress, and indicate the main impediments to the program. It will draw in part on the essay When Scientific Evidence is not Welcome and the related video.
About the speaker: Paul Richards is the Mellon Professor of the Natural Sciences (emeritus) at the Lamont-Doherty Earth Observatory of Columbia University, where he has researched and taught aspects of seismology since 1971. His career has included both fundamental geophysics and monitoring compliance with nuclear arms control treaties. He spent two separate years in the U.S. Arms Control and Disarmament Agency (in the Reagan and Clinton administrations) and was part of the US team that negotiated the Comprehensive Nuclear-Test-Ban Treaty. He has worked for decades with U.S. government institutions on explosion monitoring, and with the CTBT Organization in Vienna. He continues to conduct research on methods to improve the monitoring of earthquakes and explosions.