The IMS uses the following four state-of-the-art technologies:
Seismic: 50 primary and 120 auxiliary seismic stations monitor shockwaves in the Earth. The vast majority of these shockwaves – many thousands every year – are caused by earthquakes. But man-made explosions such as mine explosions or the North Korean nuclear tests in 2006 and 2009, are also detected.
Hydroacoustic: 11 hydrophone stations “listen” for sound waves in the oceans. Sound waves from explosions can travel extremely far underwater.
Infrasound: 60 stations on the surface can detect ultra-low frequency sound waves (inaudible to the human ear) that are emitted by large explosions.
Radionuclide: 80 stations measure the atmosphere for radioactive particles; 40 of them also pick up noble gas. Only these measurements can give a clear indication as to whether an explosion detected by the other methods was actually nuclear or not. They are supported by 16 radionuclide laboratories.
1. THE VERIFICATION REGIME STANDS READY.
2. AN EXPLOSION TRIGGERS SHOCKWAVES THAT ARE DETECTED BY SEVERAL STATIONS ...
3. ... WHICH IMMEDIATELY TRANSMIT THE SIGNALS THROUGH SATELLITES ...
The International Data Centre at the CTBTO’s headquarters in Vienna receives the data from the global monitoring stations. The data are processed and distributed to the CTBTO’s Member States in both raw and analyzed form. When North Korea tested in 2006 and 2009, the Member States received information about the location, magnitude, time and depth of the tests within two hours.
On-site inspections can be dispatched to the area of a suspicious nuclear explosion if the data from the IMS indicate that a nuclear test has taken place there. Inspectors will collect evidence on the ground at the suspected site. Such an inspection can only be requested and approved by Member States once the CTBT has entered into force. A large on-site inspection exercise was carried out in September 2008 in Kazakhstan.
4. ... AND SECURE DATA CONNECTIONS ON THE GROUND TO THE CTBTO IN VIENNA.
HELPING TSUNAMI WARNING AND THE ENVIRONMENT The huge amount of data collected by the stations can also be used for other purposes than detecting nuclear explosions. They can provide tsunami warning centres with almost real-time information about an underwater earthquake, thus helping to warn people earlier and possibly saving lives. During the March 2011 Fukushima power plant accident, the network's radionuclide stations tracked the dispersion of radioactivity on a global scale. The data could also help us better understand the oceans, volcanoes, climate change, the movement of whales
and many other issues.
For more information please visit www.ctbto.org
5. FROM THE CTBTO, RAW DATA AND THEIR ANALYSIS ARE DISTRIBUTED TO THE CTBT MEMBER STATES.