Maps updated for tsunami warning system

US officials are updating maps of Puerto Rico and the US Virgin Islands to identify areas susceptible to floods and tidal waves, the first step toward creating a tsunami warning system in the region.

Maps of some areas in the two US Caribbean possessions are no longer accurate because erosion and movement of earth plates have altered altitudes in some areas, said Dave Doyle, the chief geodetic surveyor of the US National Oceanic and Atmospheric Administration. The maps should be completed next year.

Mr. Doyle spoke during a meeting of officials from eight Caribbean territories and countries to discuss creating a tsunami warning system.

The Caribbean has no such system, even though its seabed is gouged by some of the world’s deepest trenches where tidal waves are generated. Discussion about a regional warning system intensified after the 26 December tsunami in Asia that killed more than 170,000 people in 11 countries.

Mr. Doyle urged officials to update maps of their own countries. The next step would be to install equipment like global positioning transmitters and tidal height monitors that would allow surveyors to regularly update maps, Mr. Doyle said.

An earthquake in the Virgin Islands could trigger a tsunami, which could hit Trinidad in 90 minutes, said Steve Parris, deputy director of the U.S. Virgin Islands Territorial Emergency Management Agency.

A tsunami triggered by an earthquake in the Puerto Rico trench – one of the deepest underwater canyons in the world at 27,355 feet – could hit the US Virgin Islands in less than eight minutes, Parris said.

Tensions in the Puerto Rico, Hispaniola and Cayman Trenches which ring the Caribbean, force tectonic plates to sink under one another as they collide, producing frequent earthquakes and underwater landslides. The deeper the water, the quicker a tsunami wave forms.

The last fatal tsunami in the Caribbean occurred in 1946 when an 8.1-magnitude earthquake in the Hispaniola Trench triggered a tidal wave that killed an estimated 1,700 people in the Dominican Republic and Haiti.