The CTBTO signed an agreement with South Korea on October 31 to share tsunami early warning data with the country, making it the ninth CTBTO member state to do so. The International Data Centre (IDC) of the CTBTO, with assistance from the United Nations Educational, Scientific and Cultural Organization (UNESCO), provides early warning data on tsunamis using a combination of seismic and hydroacoustic monitoring stations to detect "any strong, shallow earthquake under the seafloor" which could trigger a tsunami, according to UNESCO. The IDC currently utilizes data from 40 different monitoring stations in the Pacific to detect earthquakes beneath the ocean floor.
The CTBTO member states decided to allow the dissemination of IDC data for tsunami warnings following the devastation caused by the earthquake, and corresponding tsunami, off of the coast of Sumatra, Indonesia in December of 2004. The CTBTO and UNESCO tested the efficacy of IDC warning data in 2005, determining that IDC data reached tsunami warning centers and national government faster than the other warning networks, with a maximum delay of just 30 seconds. The IDC currently shares tsunami early warning data with Australia, France, Indonesia, Japan, the Philippines, South Korea, Thailand, Turkey, and the United States.
There are several potential civilian uses for the IDC outside of its main purpose as a nuclear explosion detection network. In addition to providing early warning data on tsunamis, the IDC is capable of assisting the aviation industry in identifying ash plumes resulting from volcanic eruptions. Additionally, it can locate downed aircraft and provide the exact time of impact via seismic stations, and provide warnings of underwater volcanic eruptions and the breakup of ice shelves leading to the creation of large icebergs through its hydroacoustic capabilities. The IDC can also deliver crucial information to countries downwind of nuclear accidents by utilizing its radionuclide stations, which was demonstrated following the Fukushima disaster.