UNESCO & CTBTO: Working together to issue timely alerts
Tsunami is a Japanese word meaning ‘harbour wave’. Tsunamis are primarily generated from an underwater shallow earthquake. They are usually small in deep waters, but become large and cause damage when they approach coasts or harbours. A characteristic of tsunamis is that their destructive impact can occur far away from the area of origin.
Tsunami warning centres and regional tsunami warning systems build on existing detection, verification and communication networks such as international seismic and sea level networks. These include the international seismic monitoring network, the international array of sea level measuring stations (the Global Sea Level Observing System, the Global Telecommunication System of the World Meteorological Organization and associated public geostationary satellites) and the internet.
Massive Indonesian tsunami triggers development of more tsunami warning systems
No single country can develop basin wide tsunami detection systems. As a consequence, the Intergovernmental Oceanographic Commission of the United Nations Educational, Scientific and Cultural Organization (UNESCO-IOC) has since 1965 been responsible for the intergovernmental coordination of the Pacific Tsunami Warning System (PTWS). Following the devastating tsunami of 26 December 2004 in the Indian Ocean, the IOC Member States requested that similar warning systems be developed for the Indian Ocean, the Caribbean Sea and adjacent regions as well as the northeast Atlantic, the Mediterranean and connected seas. UNESCO-IOC is primarily concerned with international coordination among nations, while the operational duties of the tsunami warning centres reside with national agencies.
Also following the 2004 tsunami, UNESCO-IOC and the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) agreed to explore the potential of using data from the International Monitoring System (IMS) for tsunami warning purposes.
The CTBTO decided at its special session on 4 March 2005 to cooperate with UNESCO-IOC on a possible contribution to an effective tsunami warning system. The two organizations agreed to share efforts to facilitate the development and operation of tsunami warning centres. Initially the CTBTO authorized the exploratory provision of data from the IMS requested by national authorities and by international tsunami warning organizations that were recognized by UNESCO-IOC. In accordance with a decision taken by the CTBTO’s Working Group concerned with verification issues, UNESCO-IOC has to approve/recognize the national tsunami warning centres that have submitted requests to the CTBTO to use seismic and other IMS data for purposes of producing tsunami warnings. These centres are officially nominated by Member States to UNESCO-IOC and are national institutions that adhere to the intergovernmental governance of UNESCO.
Working together to issue earlier tsunami alerts
The provisional arrangement between the two organizations proved effective in the development phase of the new tsunami warning systems. In recognition of the successful trial period, an agreement was signed on 3 February 2010 by Irina Bokova, Director-General of UNESCO, and Tibor Tóth, Executive Secretary of the CTBTO, to enhance cooperation between the two organizations, notably for the benefit of tsunami early warning systems and capacity building in developing countries.
The benefits of using the IMS stations as a supplement to the existing network of seismic stations are:
- a more uniform setting of the stations in the network;
- higher data availability and faster data transmission;
- highly accurate data due to equipment that record seismic waves over a wide range of frequencies; and
- Some IMS stations are in isolated places not populated by other networks.
All of these are factors that contribute to the more accurate determination of earthquake parameters and hence to the issuing of earlier tsunami alerts deriving from potentially tsunamigenic earthquakes.
As of March 2012, Australia, France, Indonesia, Japan, Malaysia, the Philippines, Thailand, Turkey and the USA had taken advantage of incorporating CTBTO seismic data into the use of their national tsunami monitoring. Additional countries are expected to sign agreements with the CTBTO in the near future. As an indicator, in 2011, about 2.3 gigabytes of IMS primary seismic, auxiliary seismic and hydroacoustic data were sent in near-real time daily to tsunami warning organizations. The provision of seismic data is not the only outcome of the strengthened CTBTO – UNESCO collaboration. UNESCO-IOC and the CTBTO have partnered in assisting Haiti to develop its capacity for seismic and tsunami monitoring.
Source: Spectrum, issue 18 (CTBTO)
Article by Wendy Watson-Wright, Executive Secretary of the Intergovernmental Oceanographic Commission of UNESCO and Assistant Director General of UNESCO
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