CTBT: Science and Technology Conference 2025 - SnT2025

8 Sept 2025, 09:00 → 12 Sept 2025, 16:00 Europe/Vienna

Hofburg Palace & Online

The Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) relies on innovation to enhance the capabilities of the Treaty’s verification regime as well as to help move the Treaty closer to universalization and entry into force. As the eighth event in the CTBT: Science and Technology Conference series, SnT2025 will bring together well over 1000 scientists, technologists, academics, students, and delegates from the CTBTO’s policy making organs. In addition, representatives from the fields of research and development, science diplomacy, science advisory, media and advocacy are invited to attend the conference.

SnT2025 is scheduled to take place at the Hofburg Palace in Vienna, Austria and online, to create a worldwide inclusive conference with the objective to gather global support.

Please read the announcement brochure for more!

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The SnT2025 is organised by the CTBTO with the financial support of the Austrian Federal Ministry for European and International Affairs and the European Union.

               

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SnT2025 Scientific Objectives:

To identify methods and technologies that have the potential to improve nuclear-test-ban monitoring and on-site inspections, including emerging and game-changing approaches.

To highlight how scientific developments and cooperation can support national needs, frame policy objectives in support of the CTBT and promote its universalization.

To connect, inspire and integrate diverse communities involved in nuclear-test-ban monitoring and on-site inspection and to enhance diversity across gender, geography and generations, and to include early career professionals and youth.

To impact global society by promoting civil and scientific applications, capacity building and training, mentoring and skills development related to nuclear-test-ban monitoring and evolving verification techniques.

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Dates and key deadlines:

• 16 September 2024: Registration for the Conference opens, and it will remain open until the Conference
• 7 October 2024: Abstract submission opens
• 14 January 2025: Deadline for abstract submission and application for financial support
• 31 August 2025:  deadline for uploading e-posters, lightning talk and oral presentation material

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Monday 8 September

Opening

E-poster

Keynote on Myanmar earthquake

E-poster

E-poster

Coffee break

E-poster

E-poster

E-poster

Tuesday 9 September

Registration

High-Level Plenary

12:30 Lunch break

O3.1 Seismic, Hydroacoustic and Infrasound Technologies and Applications

Conveners: Mr Anooshiravan Ansari (International Institute of Earthquake Engineering and Seismology (IIEES)), Mr Benoit Doury (CTBTO Preparatory Commission)

O5.1 Synergies with Global Challenges

Conveners: Mr Guillermo Rocco (CTBTO Preparatory Commission), Ms Kathy Whaler (University of Edinburgh)

1 Monitoring whale populations from acoustic data over large temporal and spatial scales

Research using acoustic recordings to estimate animal population sizes is being applied increasingly frequently to both marine and terrestrial species. Here, data from the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO) International Monitoring System (IMS) hydroacoustic stations have been used to monitor baleen whales. For example, several baleen whale species have been recorded at Diego Garcia in the Indian Ocean including blue (Balaenoptera musculus), fin (B. physalus) and suspected Omura’s whales (B. omurai). The CTBTO IMS has been collecting data at Diego Garcia across multiple decades and the placement of the hydrophones in the deep sound channel enables long-range detection of whale calls. By covering both large spatial and temporal scales, the CTBTO IMS is a valuable dataset for the potential assessment of trends in population size and distribution of several baleen whale species. To estimate whale population densities from CTBTO IMS instruments, simulation-based statistical methods have been implemented to estimate detection probability, a key parameter required for density estimation. The simulations require several data inputs including bearings to target whale calls, transmission loss data, noise level measurements and assumed source levels of the calls. Results from a case study focusing on Sri Lankan blue whale calls will be presented.

Speaker: Ms Danielle Harris (University of St Andrews)

2 Verification and Modelling of Tsunami Arrival Time and Wave Height Along Thailand's Andaman Sea Coast Using an Enhanced TOAST

After the Sumatra-Andaman earthquake, leading to a tsunami devastating Thailand's west coast, concerns were raised about the effects on infrastructure and human life. This study aims to model Tsunami Arrival Times and Wave Heights along the Andaman Sea Coast of Thailand using the TOAST (Tsunami Observation and Simulation Terminal) module integrated into the SeisComP software. The default bathymetry resolution was modified from 3.7 km to 0.46 km, and the impacted area was set to more detail at the subdistrict level to improve the accuracy of hazard assessments. The 2004 Indian Ocean Tsunami simulations and actual tidal gauge data were compared to evaluate the accuracy of the improved TOAST model. There was no significant difference in the first tsunami wave arrival. However, the maximum wave arrival time was close to the actual data at the Kuraburi tide gauge station, which was 9 minutes early, and 28 minutes late at Taphao Noi tide gauge station. Simulations along the Sumatra-Andaman subduction zone identified Lam Kaen Subdistrict as the first impacted area and Thung Maphrao Subdistrict as having the highest wave height. Thus, the adjusted TOAST can inform the public about tsunami arrival times on Thailand's west coast.

Speaker: Ms Chutimon Promsuk (Thai Meteorological Department)

3 The effect of seasonal storm conditions on the microbarom with implications for IMS infrasound station noise

The International Monitoring System (IMS) infrasound network’s ability to detect atmospheric nuclear detonations is limited by a combination of wind-noise, anthropogenic sources, and the microbarom, the constant and globally ubiquitous infrasonic noise driven by oceanic waves. The presence of seasonal weather conditions may increase the strength of the microbarom, further increasing background noise at IMS stations. The microbarom may also strengthen due to seasonal variation in sea ice extent at high latitudes. In several studies, sea ice has been shown to inhibit the generation of the microseism, the seismic noise equivalent of the microbarom. Here we analyze ten years of acoustic data collected at six high-latitude IMS infrasound stations alongside hemispheric sea ice extent. We find that microbarom strength varies smoothly with the seasons by a factor of 2-5 but is out of phase with hemispheric sea ice extent. At each station, the maximum and minimum microbarom strength occurs 2-4 months before the maximum and minimum sea ice extent, respectively. We do not observe a clear relationship indicative that microbarom strength is diminished by hemispheric-scale sea ice. Instead, we now consider that other hemispheric-scale seasonal variations over the world’s oceans will outweigh the effects of sea ice extent on the strength of the microbarom.

Speaker: Loring Schaible (Sandia National Laboratories (SNL))

4 The Volcanic Information System: Long-Range Infrasound Monitoring of Volcanic Eruptions

Explosive volcanic eruptions produce large amount of infrasound (<20 Hz), which can propagate over hundreds to thousands of kilometers in the atmosphere. These eruptions also inject large amounts of ash in the atmosphere, posing a direct threat to commercial flights and the population under the ash plume trajectory.

The Volcanic Information System (VIS) was developed within the Atmospheric dynamics Research InfraStructure in Europe (ARISE) project, in collaboration with the Toulouse Volcanic Ash Advisory Center (VAAC). The VIS is a prototype monitoring system that uses long-range (>250 km) infrasound detections to remotely detect and notify explosive eruptions.

The VIS was designed to use observations from the global International Monitoring System (IMS) infrasound network, but also non-IMS infrasound arrays. To detect an eruption, the VIS relies on the Infrasound Parameter (IP), which accounts for propagation effects, detection persistency and amplitude.

In the current study, we statistically assess the reliability of the VIS to detect, locate and raise automatic notifications for the VAACs, considering global datasets derived from all available IMS stations (2003-present). We also present the current web-based service prototype and the road map to make it available to the public.

Speaker: Mr Rodrigo De Negri (Laboratoire Magmas et Volcans, Université Clermont Auvergne)

5 Wandering albatrosses ride infrasonic waves over large geographic scales

Predicting and responding to changing environmental conditions is an essential part of making optimal decisions about movement. Over small spatial scales such decisions may be guided by short-range cues, but it can be unclear what cues underlie movement at scales exceeding 1000s of km. Infrasound could form such a cue. In marine habitats, infrasound is largely generated by non-linear wave interactions that are associated with storms. For ocean-faring species, infrasound sensitivity could therefore help animals to either avoid these weather fronts, or if such conditions are favourable to movement, move towards them. Yet despite its potential utility as a cue, behavioural responses to infrasound have been investigated in very few species. We tested whether one of the furthest ranging seabirds, the wandering albatross, shows movement trajectories consistent with responsiveness to infrasound. We used high-resolution GPS data collected from 89 albatrosses breeding on Crozet Island, in combination with modelled infrasound maps, to show that albatrosses move towards areas containing higher infrasound levels and propose that this might allow them to anticipate conditions optimal for flight at long distances. This provides the first evidence for infrasound responsiveness in a free-ranging bird, broadening our understanding of how animals perceive and navigate vast featureless habitats.

Speaker: Ms Samantha Patrick (University of Liverpool)

Panel "Today's minds tomorrow's innovators"

14:45 Coffee break

Keynote on the Impact of Long-Term Shifts in Environmental Conditions on Society

O3.2 Radionuclide Technologies and Applications

Conveners: Anders Ringbom (Swedish Defence Research Agency (FOI)), Nikolaus Helmut Hermanspahn (CTBTO Preparatory Commission)

O3.5 Analysis of Seismic, Hydroacoustic and Infrasound Monitoring Data

Conveners: Mr Christos Saragiotis (CTBTO Preparatory Commission), Mr Ronan Le Bras (Former CTBTO Preparatory Commission)

Panel on the Impact of Extreme Conditions on the CTBTO Monitoring System

EU session

O3.6 Analysis of Radionuclide Monitoring Data

Conveners: Mr Ian Hoffman (CTBTO Preparatory Commission), Ms Sylvia Generoso (Commissariat à l’énergie atomique et aux énergies alternatives (CEA))

O4.4 International Monitoring System Sustainment into the future

Conveners: Ms Anne Lycke (NORSAR), Ms Michelle Grobbelaar (CTBTO Preparatory Commission)

Wednesday 10 September

Lightning talks P2.3

Side event "The Role of Metrology in Seismic, Hydroacoustic, and Infrasound (SHI) Monitoring Activities"

Side event on Artificial Intelligence (AI)

Coffee break

Lightning talks P2.3, P3.2, P3.6

P2.3 Atmospheric and Subsurface Radionuclide Background and Dispersion: e-poster session

E-poster session with display of each e-poster on an assigned touchscreen

Lightning talks P3.3, P4.5

Keynote on machine learning, deep learning and high-performance computing

This talk aims to explore the potential transformative impact of machine learning, deep learning, and high-performance computing on enhancing the operational capabilities of CTBTO in global monitoring and verification. Advanced AI techniques and scalable computational resources open up an opportunity for CTBTO to improve the detection, localization, and analysis of nuclear test signatures across seismic, hydroacoustic, infrasound, and radionuclide data streams. The presentation will discuss expected advancements in data-driven models, real-time processing, and automated decision-making, which could enhance accuracy and reduce response times. Furthermore, it will consider future prospects for integrating cutting-edge AI and HPC technologies to strengthen verification efforts, aiming to ensure the effectiveness and reliability of the Treaty’s monitoring regime.

P2.3 Atmospheric and Subsurface Radionuclide Background and Dispersion: e-poster session

E-poster session with display of each e-poster on an assigned touchscreen

P3.2 Radionuclide Technologies and Applications: e-poster session

E-poster session with display of each e-poster on an assigned touchscreen

P3.6 Analysis of Radionuclide Monitoring Data: e-poster session

E-poster session with display of each e-poster on an assigned touchscreen

Panel "Machine Learning, Deep Learning and High-Performance Computing: Transforming CTBTO’s Operations in Global Monitoring and Verification"

How can emerging technologies (e.g. machine learning, deep learning, artificial intelligence, cloud computing, etc.) support our core business / mission / verification sciences? The session will draw the connection between CTBTO tasks (data verification related activities) and ML/DL opportunities, identify infrastructure support for ML/DL-related activities, and discuss how to integrate ML/DL techniques into CTBTO-related software.

Lightning talks P2.1, P2.4, P4.4

P3.3 On-Site Inspection Relevant Techniques: e-poster session

E-poster session with display of each e-poster on an assigned touchscreen

P4.5 On-Site Inspection Team Functionality: e-poster session

E-poster session with display of each e-poster on an assigned touchscreen

Lunch break

Keynote "Quantum Sensing & Metrology: The Next Frontier"

O4.1 Performance Evaluation of the International Monitoring System

Conveners: ELOISA DE VILLALOBOS, Ms Paola García (Chilean Nuclear Energy Commission)

O5.2 Regional Empowerment

Conveners: Mr Jie Hou (CTBTO Preparatory Commission), Mr Marino Protti (Observatorio Vulcanológico y Sismológico de Costa Rica, Universidad Nacional (OVSICORI-UNA))

Panel "Global Innovations: Waveform Technologies"

O4.5 On-Site Inspection Team Functionality

Conveners: Mr Gregor Malich (CTBTO Preparatory Commission), Mr Peng Li (China Arms Control and Disarmament Association)

6 An ITF framework for condensed OSI exercises

The inspection team functionality (ITF) is the conceptual framework that guides the inspection team during a Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) on-site inspection (OSI). ITF provides a structured thinking space, which limits the impact of cognitive bias and noise on the decisions taken by the inspection team. With that purpose, ITF acts as a regulatory system that slows down the human impulse to quickly reach conclusions based on incomplete information and expert bias. The rigor and safety provided, however, collides with the artificial time pressure imposed on the inspection team during abridged OSI exercises. This has led to the implementation of ad-hoc shortcuts that inadvertently erode the protections provided by the ITF. In this paper we present an approach to be used during time condensed OSI field exercises. This approach emphasises the importance of the information collected, the foundations of objective decision making, and the resourcing of field missions through the search logic. Time compression can also be accommodated through modification to meeting formats and template schedules for the implementation of the ITF cycle over several days. We have also developed guidance on exercise and scenario planning to protect the quality of inspection and decision making processes under the time pressure often imposed when implementing ITF.

Speaker: Mr Luis Gaya Pique (CTBTO Preparatory Commission)

How to upload files to Indico_rev2.mp4

O4.5-542-Gaya-Pique_ForTest.pdf

O4.5-542-Gaya-Pique_ForTest.pptx

O4.3 Use of enabling Information Technologies

Conveners: Mr Oladoyin Odubanjo (The Nigerian Academy of Science), Mr Pavel Strachota (CTBTO Preparatory Commission)

Panel "Global Innovations: Radionuclide Technologies"

Coffee break

O1.2 The Solid Earth and its Structure

Conveners: Charlotte Rowe (Los Alamos National Laboratory (LANL)), Mr Ehsan Qorbani Chegeni (CTBTO Preparatory Commission)

O2.3 Atmospheric and Subsurface Radionuclide Background and Dispersion

Conveners: Mr Man-Sung Yim (Texas A&M University), Mr Robin Schoemaker (CTBTO Preparatory Commission)

Keynote on IMS Sustainment

Panel "IMS sustainment now and into the future"

Thursday 11 September

Lightning talks P1.4, P3.4, P5.1

P2.1 Characterization of Treaty-Relevant Events

E-poster session with display of each e-poster on an assigned touchscreen

P2.4 Historical Data from Nuclear Test Monitoring

E-poster session with display of each e-poster on an assigned touchscreen

P4.4 International Monitoring System Sustainment into the future

E-poster session with display of each e-poster on an assigned touchscreen

Side event on YPN

Coffee break

Lightning talks P3.5

P1.4 Multidisciplinary Studies of the Earth’s Subsystems

E-poster session with display of each e-poster on an assigned touchscreen

P3.4 Integrating Data from Different Monitoring Technologies

E-poster session with display of each e-poster on an assigned touchscreen

P5.1 Synergies with Global Challenges

E-poster session with display of each e-poster on an assigned touchscreen

O2.1 Characterization of Treaty-Relevant Events

Conveners: Mario Zampolli (CTBTO Preparatory Commission), Mr Mohamed Nabil Mohamed ElGabry (National Research Institute of Astronomy and Geophysics (NRIAG))

O5.3 Outreach

Conveners: Joseph Ballard (CTBTO Preparatory Commission), Ms Magdalene Wangui Wanyaga (SandRose Ltd, CYG & YPN)

Lightning talks P3.5, P2.2, P3.1

P3.5 Analysis of Seismic, Hydroacoustic and Infrasound Monitoring Data

E-poster session with display of each e-poster on an assigned touchscreen

O3.4 Integrating Data from Different Technologies

Conveners: Dr Gustavo Haquin Gerade (Soreq Nuclear Research Center), Hossein Hassani

Lightning talks P4.1, P4.2, P4.3

Lunch break

P2.2 Seismoacoustic Sources in Theory and Practice

P3.1 Seismic, Hydroacoustic and Infrasound Technologies and Applications

E-poster session with display of each e-poster on an assigned touchscreen

P3.5 Analysis of Seismic, Hydroacoustic and Infrasound Monitoring Data

E-poster session with display of each e-poster on an assigned touchscreen

Keynote on ATM in support of radionuclide detection

O1.3 The Oceans and their Properties

Conveners: Ms Silvia Blanc (Argentinian Navy Research Office (ARA) & UNIDEF (CONICET)), Mr Tiago Oliveira (CTBTO Preparatory Commission)

O2.4 Historical Data from Nuclear Test Monitoring

Conveners: Ms Anna Berezina (Institute of Seismology, National Academy of Sciences of the Kyrgyz Republic), Mr Gerhard Graham (CTBTO Preparatory Commission)

Panel "Operational Detection Capabilities of the CTBTO"

O1.1 The Atmosphere and its Dynamic

Conveners: Ms Anne Tipka (CTBTO Preparatory Commission), Ms Daniela Ghica (National Institute for Earth Physics (NIEP))

Keynote on broadening the impact of OSI exercises and field tests

PTS session

Panel "Utilizing Data from On-Site Inspection Activities: Insights from OSI Exercises and Field Tests"

Coffee break

O2.2 Seismoacoustic Sources in Theory and Practice

Conveners: Mr Paul Granston Richards (Lamont-Doherty Earth Observatory, Columbia University), Mr Rodrigo Chi-Durán (CTBTO Preparatory Commission)

Keynote on NDCs and G-cube: Geography, Gender, Generation

O3.3 On-Site Inspection Relevant Techniques

Conveners: Aled Rowlands (CTBTO Preparatory Commission), Ms Dharani Wijesundara (Geological Survey and Mines Bureau, Sri Lanka)

Panel "Gender, Geography, Generations: How NDCs Shape the World Today and Tomorrow"

Friday 12 September

Lightning talks P1.2

Side event on DAS

P4.1 Performance Evaluation of the International Monitoring System

E-poster session with display of each e-poster on an assigned touchscreen

P4.2 Systems Engineering for International Monitoring System and On-Site Inspection

E-poster session with display of each e-poster on an assigned touchscreen

P4.3 Use of enabling Information Technologies

E-poster session with display of each e-poster on an assigned touchscreen

Coffee break

Lightning talks P5.2, P5.3

P1.2 The Solid Earth and its Structure

E-poster session with display of each e-poster on an assigned touchscreen

O4.2 Systems Engineering for International Monitoring System and On-Site Inspection

Conveners: Ms Barbara Nadalut (Comprehensive Nuclear-Test-Ban Treaty Organization), Rika Swastikarani (Indonesian Agency for Meteorology, Climatology and Geophysics (BMKG))

Lightning talks P1.1, P1.3

P5.2 Regional Empowerment

E-poster session with display of each e-poster on an assigned touchscreen

P5.3 Outreach

E-poster session with display of each e-poster on an assigned touchscreen

Panel "Adapt or Become Obsolete: Emerging Technologies as a Means to Achieve International Organizations' Mandates and Goals"

P1.1 The Atmosphere and its Dynamics

E-poster session with display of each e-poster on an assigned touchscreen

7 What can we learn from a comparison of European Centre for Medium-Range Weather Forecasts and National Centers for Environmental Prediction-driven source-receptor sensitivity fields?

One of important challenges the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) has been facing is to put an error bar on its atmospheric transport modelling (ATM) simulations. A well-established approach to address this question by the meteorological community is to run, for a given date, multiple simulations. These simulations constitute an ensemble, whose instances, or members, differ in such a way that the differences are representative of underlying meteorological uncertainty. Awaiting implementation of such an ensemble-based ATM system at the CTBTO, we propose to investigate a simple initial comparison. In fact, for many years, the CTBTO has been producing two instances of source-receptor sensitivity (SRS) fields using two sources of input meteorological data, namely, the European Centre for Medium-Range Weather Forecasts and the National Centers for Environmental Prediction. In this presentation we look into differences between these two instances of SRS fields in view of assessment of uncertainty in the ATM but also in our future derived products, essentially background characterization and probabilistic radionuclide source location.

Speaker: Monika Krysta (CTBTO Preparatory Commission)

E-Poster-Example-with CTBTO Logo (1).pptx

P1.3 The Oceans and their Properties

E-poster session with display of each e-poster on an assigned touchscreen

Lunch break

Keynote on the History of the Treaty Verification Regime

Panel "The Treaty Verification Regime across the Generations"

Closing Plenary

Closing Plenary with Award Ceremony