3. How to detect an event – an earthquake or an explosion?

A potential underground nuclear test is first detected by seismic waves generated by the explosion. Seismic monitoring is used to determine the location, time and strength (magnitude) of a seismic ‘event’. The data are further analyzed to distinguish between man-made explosions and earthquakes. Once a man-made explosion is identified, radionuclide technology may be necessary to establish the nuclear character of the explosion.

1.    Experiment to see how well the system can pick up an explosion: footage from the former Soviet Union nuclear test site Semipalatinsk, Kazakhstan; countdown from 10 to 1; pics of the explosion; footage from small town near Semipalatinsk

2.    Vienna: CTBTO staff and analysts going by subway to the CTBTO headquarters at the Vienna International Centre, arriving at the VIC’s and shots of VIC

3.    Analysts at the CTBTO looking at and studying the explosion on their computer screens etc, data bulletins, data processing pipe showing how the data is transmitted through the system.

4.    Animation of how a seismic station picks up shock waves in the ground (Energy propagates from the epicenter of a seismic event in the form of waves than can be sensed by the seismic monitoring stations in the network. Data from several stations are combined to estimate the location and time of the event. In this way, it is possible to zero in on the epicenter of the event.)

4. Radionuclide data, noble gas, and atmospheric transport modeling Civil and scientific applications

Radionuclide technology is the only verification technology capable of indicating the nuclear character of an explosion measured by the three waveform technologies (seismic, infrasound or hydroacoustic). It is used to detect either radioactive particles or radioactive noble gases, which are typically released into the atmosphere also by underground nuclear explosions. Once such substances are found, their region of origin is determined by calculating their potential flight path using meteorological data. This method is called atmospheric transport modeling (ATM).

1.    Vienna International Centre, panning to CTBTO Radionuclide station at the rooftop of the VIC, showing how particles are picked up by the station

2.    Interview with noble gas expert at the CTBTO Paul Saey    explaining that the detection of noble gas can show that an explosion is indeed nuclear

3.    Atmosphere/clouds and images of Atmospheric transport modeling

4.     Animation Earth with satellites, data processing pipe, satellite image of the ground, showing how data is transmitted via satellites from stations to the CTBTO in Vienna and to the Member States.

CTBTO data can also be used for civilian purposes such as disaster warning and mitigation. By providing seismic and hydrouacoustic data from its monitoring stations directly to Tsunami warning centres in the Indian and Pacific Ocean regions (Japan, United States, Australia, Malaysia, Indonesia and Thailand), the CTBTO network helps these centres warn populations up to two and a half minutes earlier than they can with data from other networks. CTBTO monitoring data is second-to-none regarding data timeliness, availability and quality. CTBTO data can also help with the forecasting of volcanic eruptions and earthquakes, the detection of accidental radioactive release, and the man-made impact on the Earth’s atmosphere leading to climate change.

5.    Pics of tsunamis, animation of the speed with which CTBTO data arrive at tsunami warning centres, showing how much faster the CTBTO data is compared to other data. Ash plumes from volcanoes.