The inside story of the Group of Scientific Experts and its key role in developing the CTBT verification regime

ABSTRACT This article provides an inside view of the sustained effort by the Group of Scientific Experts (GSE) which was key to the development of the international seismic network included in the 1996 Comprehensive Nuclear-Test-Ban Treaty (CTBT). Over the course of the GSE’s twenty-year-long journey, part of which was at the height of the Cold War, the GSE went from being a little-known entity that reviewed and encouraged research to designing and testing elements of a seismic verification system. Their work eventually included full-scale testing of the seismological component of the final global system that is now implemented by the Preparatory Commission of the CTBT Organization. The other three monitoring networks comprised in the treaty—radionuclide, hydroacoustic, and infrasound—are modeled after the seismic network. The article identifies some key conditions that made GSE a successful endeavor. Prime among these was the strong engagement among scientists and scientific institutions in many countries that contributed large resources. The formal work at the Conference on Disarmament in Geneva was just the tip of the iceberg, but very important. This official intergovernmental framework provided a connection to the political community, and a frame for organizing extensive global development and testing activities. GSE was given long-term mandates and self-determination of management and leadership, facilitating a sustained and goal-oriented process. Based on their leadership experience in the GSE and the CTBTO Preparatory Commission Verification Working Group, the authors also provide some reflections on how the concept of scientific expert groups and new scientific developments could prove useful in future efforts toward nuclear-disarmament verification.