Prepare for potential tsunami, says geography expert

A cost benefit analysis may be prudent for coastal flood-prone counties to combat potential damage from a powerful tsunami, an expert has said.

Ireland suffered significant tsunami damage following a monster earthquake in Portugal in 1755, which modern scientists now believed to have registered as an 8.4 on the Richter scale.

By comparison, the 2011 earthquake off Japan that caused devastating tsunamis registered as a 9.0.

Portugal has seen earthquakes of severe magnitude in 1321, 1531 and 1755, with scientists believing that another is overdue, albeit not on the scale of the 1755 disaster which ravaged Western Europe.

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The tsunami was so powerful in 1755 that it is said to have been responsible for the partial destruction of Galway’s Spanish Arch, while also making an island out of Clare’s Aughinish, which had been connected to the mainland before that.

Richard Cantwell, a senior spatial data scientist with geographical data analysis firm Gamma Location Intelligence, said although it might not be at the top of anyone’s agenda at present, it would be useful to assess Irish infrastructure’s ability to cope, considering coastal counties will suffer significant heightened flood risk by 2050.

“Tsunamis driven by seismic events in the Atlantic would be considered to be true 'Black Swan' events, extremely rare but also extremely damaging. 

"Protecting the Irish coastline against every foreseeable risk is clearly not economic, however there may be certain pieces of critical infrastructure along the coastline where a tsunami would be utterly catastrophic.

“It would be a useful exercise to conduct a high level risk assessment for this infrastructure, followed by a cost/benefit analysis,” Mr Cantwell said.

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