Situated in the Ring of Fire, an area in the Pacific Ocean where 90 percent of the world’s earthquakes and 80 percent of the world’s largest earthquakes occur, Japan has prided itself on being prepared to handle large tremors when they occur.
Reports have suggested Japan escaped a far worse fate after the 9.0 magnitude earthquake which rocked the nation last Friday because of its readiness to face some of the world’s most powerful earthquakes.
While tsunamis occur far more frequently in the Pacific than in the Atlantic, researchers in this region report evidence of at least 88 tsunamis in the Caribbean in the last 500 years. According to the University of the West Indies Seismic Research Centre, there have been ten confirmed earthquake-generated tsunamis in the Caribbean Basin in that same period with four causing fatalities. Approximately 350 people in the Caribbean were killed by these events.
While tsunamis have inflicted a small amount of losses compared to other disasters such as windstorms, earthquakes and volcanic activity, the impact of a large tsunami can be as devastating as earthquakes or an erupting volcano.
A tsunami is able to impact a large area in less time than a hurricane giving it the potential to cause destruction in large scales especially if a warning system is not in place.
The Eastern Caribbean islands lie in an area where all known causes of a tsunami are evident. Earthquakes, volcanic eruptions and landslides occur close to and around this area. Tsunamis affecting this region however will most likely occur as a result of shallow earthquakes greater than magnitude 6.5 on the Richter scale. (Belize is located in the Western Caribbean Region)
Two types of earthquakes have the potential to cause tsunamis in the Caribbean. These are earthquakes occurring within the region which may generate tsunamis affecting nearby islands.
Fifty such earthquakes with the potential to cause a tsunami occurred within the past 500 years but only 10-20 percent of these earthquakes actually generated tsunamis that caused significant flooding.
Other tremors which could cause large waves in the Caribbean are earthquakes occurring outside of the region which may generate tele-tsunamis, or ocean-wide tsunamis. These pose a somewhat lower threat than tsunamis caused from local earthquakes.
While history shows that potentially destructive tsunamis occur at an average rate of one to two per century in the Caribbean, this hazard is not the same throughout the islands. Near Puerto Rico and Hispaniola, the average rate of occurrence in this area has approached one every 50 years in the last 200 years. In other sub-regions such as the southern Caribbean, where Trinidad and Tobago is located, there are no historical records of destructive tsunami impacts.
While there is the potential for a devastating tsunami in the region, no early warning system has as yet been developed for the Caribbean.
The first full-scale test of the tsunami warning system in the Caribbean has highlighted the need to reinforce preparations as well as improve communication, evacuation plans and the role of the private sector.
The simulated tsunami alert, dubbed Caribe Wave 2011, was carried out on 23 March and involved 34 countries. Under the test scenario, a 7.6-magnitude earthquake was signaled off the coast of the Virgin Islands, which generated a tsunami with waves reaching of up to ten meters
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The exercise tested the Tsunami and Other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (Caribe EWS), which was set up in 2005 under the aegis of the Intergovernmental Oceanographic Commission (IOC) of the UN Educational, Scientific and Cultural Organization (UNESCO).
“The exercise highlighted a number of gaps in the transmission of information,” UNESCO stated in a news release, noting that in several areas, the message was not received by the Global Telecommunications System (GTS).
In other cases, reception of messages via the Emergency Managers Weather Information Network (EMWIN) failed. At national level only a few mobile telephone operators joined the exercise.
News Sources:
From Trinidad and Tobago’s Newsday
Caribbean 360
