- Tsunami warning system
A tsunami warning system is a system to detect
tsunamis and issue warnings to prevent loss of life and property. It consists of two equally important components: a network of sensors to detect tsunamis and a communications infrastructure to issue timely alarms to permit evacuation of coastal areas.
There are two distinct types: international tsunami warning systems, and regional warning systems. Both depend on the fact that, while tsunamis travel at between 500 and 1,000 km/h (around 0.14 and 0.28 km/s) in open water, earthquakes can be detected almost at once as
seismic waves travel with a typical speed of 4 km/s (around 14,400 km/h). This gives time for a possible tsunami forecast to be made and warnings to be issued to threatened areas, if warranted. Unfortunately, until a reliable model is able to predict which earthquakes will produce significant tsunamis, this approach will produce many more false alarms than verified warnings. In the currect operational paradigm, the seismic alerts are used to send out the watches and warnings. Then, data from observed sea level height (either shore based via tide gauges or deep ocean DART buoys) are used to verify the existence of a tsunami. Other systems have been proposed to augment the warning paradigm. For example, it has been suggested that the duration and frequency content of t-wave energy (which is earthquake energy trapped in the ocean SOFAR channel) is indicative of an earthquakes tsunami potential [Salzberg, 2006] . The first rudimentary system to alert communities of an impending tsunami was attempted in Hawaiiin the 1920s. More advanced systems were developed in the wake of the April 1, 1946and May 23, 1960tsunamis which caused massive devastation in Hilo, Hawaii.
International warning systems (IWS)
Tsunami warnings for most of the
Pacific Oceanare issued by the Pacific Tsunami Warning Center(PTWC), operated by the United States's NOAAin Ewa Beach, Hawaii. NOAA's West Coast/Alaska Tsunami Warning Center (WC/ATWC) in Palmer, Alaskaissues warnings for the west coast of North America, including Alaska, Canada, and the western coterminous United States. PTWC was established in 1949, following the 1946 Aleutian Island earthquakeand a tsunami that resulted in 165 casualties on Hawaii and in Alaska; WC/ATWC was founded in 1967. International coordination is achieved through the International Coordination Group for the Tsunami Warning System in the Pacific, established by the Intergovernmental Oceanographic Commissionof UNESCO. [http://ioc.unesco.org/itsu/]
Indian Ocean (ICG/IOTWS)
After the 2004 Indian Ocean Tsunami which killed almost 230,000 people, a
United Nationsconference was held in January 2005 in Kobe, Japan, and decided that as an initial step towards an International Early Warning Programme, the UN should establish an Indian Ocean Tsunami Warning System.This then resulted in a system of warnings in Indonesia.This will also save the lives and the livelihood of the people.
North Eastern Atlantic, the Mediterranean and connected Seas (ICG/NEAMTWS)
The First Session of the Intergovernmental Coordination Group for the Tsunami Early Warning and Mitigation System in the North Eastern Atlantic, the Mediterranean and connected Seas (ICG/NEAMTWS), established by the
Intergovernmental Oceanographic Commissionof UNESCOAssembly during its 23rd Session in June 2005, through Resolution XXIII.14, took place in Rome on 21st and 22nd November, 2005.The Meeting, hosted by the Government of Italy (Italian Ministry of Foreign Affairs and Ministry for Environment and Protection of the Territory), was attended by more than 150 participants from 24 countries, 13 organizations and numerous observers.
Regional warning systems
Regional (or local) warning system centres use
seismicdata about nearby earthquakesto determine if there is a possible local threat of a tsunami. Such systems are capable of issuing warnings to the general public (via public address systems and sirens) in less than 15 minutes. Although the epicenterand moment magnitudeof an underwater quake and the probable tsunami arrival times can be quickly calculated, it is almost always impossible to know whether underwater ground shifts have occurred which will result in tsunami waves. As a result, false alarms can occur with these systems, but due to the highly localised nature of these extremely quick warnings, disruption is small.
Conveying the warning
Detection and prediction of tsunamis is only half the work of the system. Of equal importance is the ability to warn the populations of the areas that will be affected. All tsunami warning systems feature multiple lines of communications (such as
fax, radioand telex, often using hardeneddedicated systems) enabling emergency messages to be sent to the emergency services and armed forces, as well to population alerting systems (eg sirens).
No system can protect against a very sudden tsunami. A devastating tsunami occurred off the coast of
Hokkaidōin Japan as a result of an earthquake on July 12, 1993. As a result, 202 people on the small island of Okushiri, Hokkaidolost their lives, and hundreds more were missing or injured. This tsunami struck just three to five minutes after the quake, and most victims were caught while fleeing for higher ground and secure places after surviving the earthquake.
While there remains the potential for sudden devastation from a tsunami, warning systems can be effective. For example if there were a very large
subduction zone earthquake(magnitude 9.0) off the west coast of the United States, people in Japan, for example, would have more than 12 hours (and likely warnings from warning systems in Hawaii and elsewhere) before any tsunami arrived, giving them some time to evacuate areas likely to be affected.
* [http://www.cwarn.org International Tsunami warnings delivered to mobile phones]
* [http://topics.developmentgateway.org/space/highlights/viewHighlight.do~activeHighlightId=103341 Space Applications for Disaster Monitoring]
* [http://www.tsunami.noaa.gov/warning_system_works.html How does the Tsunami Warning System Work?] from the [http://www.tsunami.noaa.gov/ NOAA Tsunami website]
* [http://www.prh.noaa.gov/pr/ptwc/ Pacific Tsunami Warning Center]
* [http://wcatwc.arh.noaa.gov/ West Coast and Alaska Tsunami Warning Center]
* [http://www.ndbc.noaa.gov/Dart/dart.shtml DART]
* [http://www.geocities.com/tvhuangsg Tsunami Detector for Indian Ocean] Web & Mobile application that reports probability of tsunami occurrences from LIVE USGS data.
* [http://www.envirtech.org/envirtech_tsunameter.htm Envirtech Tsunami Warning System, based on real time seafloor observatories measuring seismic waves and sea levels]
* [http://www.ina.in/itws/ Integrated Tsunami Watcher Service] Web & SMS based Free service.
* [http://www.tsunami.noaa.gov/warnings_forecasts.html NOAA Tsunami Warnings and Forecasts]
* [http://www.dews-online.org/ DEWS - Distant Early Warning System for the Indian Ocean Region]
* [http://www.iotws.org/ Indian Ocean Tsunami Warning Center]
* [http://www.jtic.org/ Jakarta Tsunami Information Centre]
Wikimedia Foundation. 2010.
Look at other dictionaries:
Indian Ocean Tsunami Warning System — The Indian Ocean Tsunami Warning System is a tsunami warning system set up to provide warning to inhabitants of nations bordering the Indian Ocean of approaching tsunamis. It was agreed to in a United Nations conference held in January 2005 in… … Wikipedia
Warning system — A warning system is any system of biological or technical nature deployed by an individual or group to inform of a future danger. Its purpose is to enable the deployer of the warning system to prepare for the danger and act accordingly to… … Wikipedia
Early Warning System — Das Frühwarnsystem ist eine Einrichtung, die als Warnsystem aufkommende Gefahren frühzeitig erkennt und Gefährdete möglichst schnell darüber informiert. Es soll durch rechtzeitige und umfassende Reaktion helfen, Gefahren abzuwenden oder… … Deutsch Wikipedia
Pacific Tsunami Warning Center — The Pacific Tsunami Warning Center (PTWC), operated by NOAA in Ewa Beach, Hawaii, USA, is one of two tsunami warning centers in the United States. PTWC is part of an international tsunami warning system (TWS) program and serves as the operational … Wikipedia
Malaysian National Tsunami Early Warning System — Das Malaysian National Tsunami Early Warning System (MNTEWS) ist ein Tsunami Frühwarnsystem, das für die nationale Tsunami Vorhersage und die Warnung der Küstenbewohner in den gefährdeten Regionen von Malaysia zuständig ist. Inhaltsverzeichnis 1… … Deutsch Wikipedia
German Indonesian Tsunami Early Warning System — Das German Indonesian Tsunami Early Warning System (GITEWS) ist ein deutsch indonesisches Tsunami Frühwarnsystem, das eine mögliche Tsunami Gefahr erkennen und die Bevölkerung an der indonesischen Küste warnen soll. Es wird unter der Führung des… … Deutsch Wikipedia
Pacific Tsunami Warning Center — Das Pacific Tsunami Warning Center (PTWC) ist ein Tsunami Frühwarnsystem, das für die internationale Tsunami Vorhersage und die Warnung der Bevölkerung im Raum des Pazifik zuständig ist. Inhaltsverzeichnis 1 Geschichte 2 Arbeitsweise 3 Siehe auch … Deutsch Wikipedia
German Indonesian Early Warning System — Das German Indonesian Tsunami Early Warning System (GITEWS) ist ein deutsch indonesisches Tsunami Frühwarnsystem, das eine mögliche Tsunami Gefahr erkennen und die Bevölkerung an der indonesischen Küste warnen soll. Es wird unter der Führung des… … Deutsch Wikipedia
Intergovernmental Coordination Group for the Indian Ocean Tsunami Warning and Mitigation System — Die Intergovernmental Oceanographic Commission (IOC) ist eine zwischenstaatliche Kommission der UNESCO zur Ozeanografie. Die IOC stellt den Mitgliedsstaaten der UN eine Plattform zum Austausch von wissenschaftlichen Erkenntnissen und technischem… … Deutsch Wikipedia
System Architecture Evolution — (aka SAE) is the core network architecture of 3GPP s LTE wireless communication standard. SAE is the evolution of the GPRS Core Network, with some differences: simplified architecture all IP Network (AIPN) support for higher throughput and lower… … Wikipedia