In this study we present a method for comparing objects, identified on images acquired by the synthetic aperture radar (SAR). The method gives a quantitative value for the similarity of different objects, detected on the sea surface on SAR images. Aim is to track their changes and be able to identify the most similar pairs. As a case study we detect four rectangle-like objects north of the...
Atmospheric transport models (ATMs) are used to model the transport of radionuclides both to determine the origins of unknown releases and to model the background concentrations from known sources. To do this ATMs rely on meteorological information from four-dimensional numerical weather prediction (NWP) models. However, the chaotic nature of the atmosphere means that the meteorological...
Electro-optical satellite imagery provides analysts with opportunities to monitor suspicious nuclear activities in the restricted access area. The more remote sensing technology advances, the more resources available from both spatial and temporal resolution standpoints. Spatially, the area of interest that needs to be monitored by analysts has been detailed and accordingly increased;...
Beryllium-10, as measured in polar ice cores with an annual resolution, is a proxy for long term cosmic ray variability. Beryllium-10 concentration can not be used directly as a proxy for solar behavior since the signal can be distorted by atmospheric transport and deposition processes. The data on atmospheric Be-10 concentrations are rather scarce due to the laborious nature of Be-10...
The use of aerosol optical depth (AOD) has been proven as an alternative to the traditional ground level monitoring of air quality in many countries across the world. Therefore, this study based on MERRA-2 data aims: (i) to characterize the spatiotemporal and component variations of aerosols in the atmosphere over the capital cities (Luanda, Sumbe, Benguela, Huambo and Lubango) of the five...
This paper showcases the work done on the designing and the making of a bespoke readout circuit that reads and produces the measurements of a unique imaging system used to assay nuclear materials and hidden neutron and gamma emitting radionuclides. The system in itself uses neutron and Compton scattering simultaneously within three layers of detectors all baked with an 8x8 silicon...
With the development of commercial space technology, remote sensing for instance has been widely used in daily life. The availability of remote sensing images as commercially off the shelf products makes it possible for on-site inspection (OSI) application, especially for training courses and exercises. This work would carry out a commercial satellite imagery based information integration...
The Earth is continuously under the influence of solar radiation, which interacts with the Earth's magnetic field, causing various effects. One of them is the warming of the planet, keeping it in a suitable situation for the development and maintenance of life on Earth. Another is the bombardment of the Earth by plasma from solar storms, where the magnetic field acts as a protective shield...
In preparation of the next Integrated Field Exercise, and in line with the capabilities developed with past field exercises, action plan project and expert meetings, the section Equipment and Instrumentalization of the On-site Inspection (OSI) Division of the Provisional Technical Secretariat has entered into a new stage of development of its telemetry solution. In 2022, the existing data...
Wet scavenging is a vital process in atmospheric transport modelling to determine the distribution of masses. Therefore, using precipitation fields from the European Centre for Medium-Range Weather Forecast (ECMWF) data sets, which refer to a temporal integral rather than being a point value in time, as all other parameters in the Lagrangian dispersion model FLEXPART, is distorting the results...
A series of atmospheric transport experiments is being conducted to collect tracer data that will allow the refinement of meteorological models in complex terrain at short distances. Radiotracers were used to measure complex terrain flow features that influence diffusion and transport. Data were collected using an array of 22 real time radiation sensors dispersed over a 5 km region. Each...
In recent years, high altitude floating platforms with a microbarometer payload have been utilized towards infrasound detection and source characterization. The stratospheric locale is presumed to be less noisy, thus facilitating better signal detection compared to ground based sensors. High altitude sensing platforms are also considered the future of space exploration for extraterrestrial...
Knowledge about the natural background of xenon isotopes and Ar-37 in the top few meters of the soil column is crucial for the assessment of measurement of those isotopes in the course of an on-site inspection. There are many factors that control the Ar-37 concentration in soil air. Production and gas transport mechanisms have previously been investigated but less attention was put on the...
In February 2021, the Ukrainian small aperture infrasound array began recording in the Antarctic Peninsula area. This is a good step towards ensuring the implementation of the CTBT with national resources. However, only at the beginning of 2022 was it possible to organize continuous transmission of satellite data in real time. This made it possible to quickly track both regional events that...
A Field Test of on-site inspection (OSI) geophysical techniques for deep applications was conducted by the Provisional Technical Secretariat in September 2022 in the Austrian Ybbstaler Alps, with the support of external experts. The scope of the Field Test was to assess the current OSI geophysical imaging capabilities for deep applications in an integrated manner in a mountainous environment...
The Lagrangian atmospheric transport model FLEXPART is employed to investigate a broad spectrum of applications, including the transport of radioactive material emitted by nuclear events. Since its inception in 1998, FLEXPART has undergone many changes, with its last official release (version 10.4) published in 2019. At the same time, numerous versions have been developed across institutions...
There are two CTBT infrasound stations in Chilean territory, I13Cl and I14Cl, located respectively on Easter Island and the Juan Fernandez Archipelago. During the COVID-19 pandemic, a health alert was declared by the government to reduce the movement of people in Chile and thus avoid the spread of the virus to the islands. Due to this, a reduction in the local noise levels detected in these...
Microbarometer networks are in place for the detection of atmospheric infrasound waves and verification of the CTBT. The presence of turbulence and other wind-induced effects are considered a nuisance. For this reason, wind noise filters are typically in place for suppression. In this study, we establish a relation between microbarometer observations and in situ turbulence measurements at the...
Forensic seismology describes the detection and interpretation of exceptional seismic events, e.g. during an on-site inspection (OSI), or signals by plane crash, submarine explosion, bomb attacks. For basic research, forensic seismology means discovery of unknown or unexpected signals, e.g. precursors of rockslides, deep earthquakes below induced seismicity, or nano-earthquakes of active...
One of the most conclusive evidences of a violation of the CTBT is the presence in the subsoil air of elevated concentrations of Ar-37 radionuclide, which is formed in large quantities in the interaction of neutrons with calcium in rocks. Traditionally, to measure the activity of Ar-37, proportional gas counters are used, which are filled with a counting gas prepared from samples of argon with...
Based on the lessons learned during On-site Inspection (OSI) workshops; training courses and exercises, especially the Integrated Field Exercises (IFE); remotely controlled ground platform based geophysics detection systems, due to the practical application to hazard challenging conditions, would have their significance both for future real OSI activities and training courses of current stage....
The local active fault in Bali has a small magnitude (M<5) but has a destructive potential. This study used gravity data from GGMplus, topographic data from DEMNAS, and lineaments using ALOS-2 PALSAR-2 data. To identify the fault movement, we interpret the subsurface using the gravity derivative method. Identification of fault locations using lineament extraction from SAR data has been done by...
Results of a geothermal research project aimed to model structural controls of a geothermal reservoir located in the Kenyan Rift Valley will be presented. The geothermal reservoir model developed through several modelling software, using reservoir parameters like rock types, permeability, porosity and pressure distribution obtained during exploration and drilling will be based on a wide range...
In 2021 the first layout and design of the next generation on-site inspection (OSI) field laboratory was presented (Poster 3.2 -691). It highlighted the requirements, the status and future improvements of the OSI field laboratory for the development of its capability to be rapidly deployed during a CTBT OSI. Here we present some of the improvements for the OSI field laboratory, notably for the...
Satellite imagery is a powerful tool to monitor compliance of States Parties with the Comprehensive Nuclear-Test Ban Treaty (CTBT). Satellite imagery can be used by the States Parties as one of the national technical means of CTBT verification. Moderate to high spatial resolution satellite imagery is useful to investigate areas where a nuclear test may have taken place, as primary indicated by...
The objective of this paper is to demonstrate the use of the magnetic method in the on-site inspection (OSI) regime and try to find the best magnetometer for OSI applications. It will be used mainly to locate underground infrastructure. Theoretical and practical applications are used to give insight to the qualitative and quantitative information obtained from magnetic measurements. Also, the...
The Transient ElectroMagnetic Method (TEM) technique is one of the geophysical techniques used in on-site inspection. This work focuses on the mathematical and numerical modeling of this technique.
The numerical simulation made it possible to predict the response of the sensor. With the treatment of several underground configurations, the expert can acquire a good experience of...
The Wireless Independent Noble Gas Sampler (WINGS) is a mobile, modular gas sampling system designed for use in low infrastructure environments. WINGS units operate on battery power and communicate by radio connection. In the case of a suspected underground nuclear explosion (UNE), WINGS units could be deployed to detect and identify noble gases emanating from the explosion site or identify...
Observational data on atmospheric-pressure variations at the land surface have been obtained at the network of four microbarographs located in the Moscow region and processed. The analysis of data has made it possible to determine the characteristics (coherence, azimuths, and propagation velocities) of the basic arrivals of acoustic gravity waves from the atmospheric storms within a wavelength...
During search logic, the technique of environmental sampling can play a role in narrowing down the areas of interest and prioritizing the field mission. One methodology to achieve this purpose is to collect several samples from the same search zone and screen out any anomaly in the gamma spectra of the samples. To ensure a high throughput screening process it can be useful to gang the samples...
Simulations of atmospheric transport and dispersion have been demonstrated to benefit from a multiscale modeling approach that resolves both mesoscale meteorology, such as frontal passages, and microscale meteorology near the plume source, which can be heavily influenced by complex (i.e. mountainous) terrain. The atmospheric modeling community has yet to settle on recommended best practices...
In the case of an underground nuclear explosion, Ar-37 and Ar-39 are produced in rocks by neutron activation of Ca and K, respectively. Because of the very different half-lives of Ar-37 and Ar-39, the Ar-37/Ar-39 ratio in the subsurface is a function of the timing of production (pulsed vs. continuous), depth-dependent production mechanisms, and the Ca/K ratio of the rocks. The Ar-37/Ar-39...
The shape of radioactive particles varies significantly, 'from compact small-sized crystalline single particles to large amorphous aggregates' (Salbu and Lind, 2005). However, many atmospheric transport models assume perfect spheres. Since non-spherical particles experience a larger drag in the atmosphere, i.e. reduced gravitational settling, the atmospheric residence times and transport...
This paper presents the features of an innovative portable radioactive isotope identifier for the detection and identification of both gamma and neutron emitting radionuclides, or even multiple ones. The described portable isotope identifier is suited for the site inspection for its capabilities of detecting and characterizing nuclear or radioactive materials in presence of gamma shielding...
Atmospheric transport modelling (ATM) tracks the movement of released substances into the atmosphere. Dispersion of freshly emitted releases takes time to evolve, and the initial transport pathway depends strongly on surrounding conditions, such as wind patterns. Global ATM with reasonable coarse resolutions can usually reflect synoptic patterns, such as frontal systems. However,...
A gas sampler system has been designed, built, and deployed that may contribute to the near-field detection of underground nuclear explosions. The system is inexpensive, portable, and autonomously collects samples for subsequent lab analysis. Collection duration and interval parameters can be adjusted using Wi-Fi or other communications network based on the intended collection site....
The International Atomic Energy Agency Department of Safeguards deployed the Geo-based Data Integration (GDI) platform for information integration, analysis, and activity planning involving geospatially-related information used for nuclear safeguards verification. GDI provides interactive, layered maps in a secure, user-friendly collaborative environment for IAEA inspectors, analysts and...
Explosive volcanic eruptions produce powerful infrasound that can propagate thousands of kilometers in atmospheric waveguides. The International Monitoring System (IMS) infrasound network has now captured numerous acoustic signals from explosive volcanic eruptions. Remote infrasound has proven useful to locate and characterize subaerial volcanic source parameters (e.g. eruption chronology and...
The on-site inspection (OSI) is the final component of the Comprehensive Nuclear-Test-Ban-Treaty (CTBT) verification regime that will help determine whether a nuclear explosion occurred; facts may also be gathered to determine who was responsible for the Treaty violation. The techniques include ground based, airborne, and laboratory elements. Because technologies involving some of the methods...
We model the atmospheric transport of cosmogenic Beryllium-7 within the time period 1950-2100, to shed light on the complex interplay of atmospheric dynamics, changing atmospheric background conditions, deposition mechanisms and solar activity. Due to the short half-life of Beryllium-7 (around 53 days), the ground level concentration of this cosmogenic isotope is particularly suitable to be...
Infrasound technology has been employed to investigate acoustic signatures of severe weather events in the past and this study aims at characterizing, for the first time, the infrasound detections that can be related to Mediterranean hurricanes (Medicanes). These mesocyclones pose a serious threat to coastal infrastructures and lives because of their strong winds and intense rainfalls. This...
The use of remotely controlled platforms (RCP) during an on-site inspection (OSI) is an open topic, especially regarding aerial platforms. Such devices did not exist, or at least were not commercially available, when the Treaty was opened for signature and ratification, and therefore there is an ongoing debate regarding the conduct of inspection activities and health and safety related...
The importance of characterizing the amplitude and spatial variation of the geophysical anomalies created by on-site inspection (OSI) relevant observables is well known. By understanding such characteristics, it is possible to design the different geophysical surveys and to realistically assess the capability of a certain OSI technique to detect a potential observable. As part of the Action...
Infrasound propagation is mainly driven by the seasonal changes in stratospheric winds. However, small scale perturbations like gravity waves also affect the detection capability of the infrasound station network of the International Monitoring System. Simulations of atmospheric models explicitly resolving gravity waves are used to investigate the effect of these perturbations on infrasound...
Vertical profiles of particulate aerosols and meteorological fields were obtained before, during, and after the invasion of regional pollutants over the mid-hill Trishuli and Sunkoshi River valleys that encroach deep into the Central Nepal Himalayas. Particulate aerosols and met-sensors integrated unmanned aerial vehicle was deployed for the purpose. Probing up to 500 m above the ground, more...
