On November 1st, 1755, a massive earthquake occurred in the Atlantic Ocean about 120 miles from the Algarve in Portugal. There was massive loss of life from the earthquake in Portugal, particularly in Lisbon – ironically, the churches were full of people gathered to remember the dead (it was All Souls Day) and many died due to falling masonry. Just as in the more recent Indian Ocean earthquake, a tsunami swept in from the sea in the aftermath of the quake, sending huge waves across the quay in Lisbon harbour and drowning the hundreds more people. Worse still, fire turned out to be the biggest killer, and many who were spared death by falling buildings or the tsunami were killed in the huge fires that swept though the city.
The earthquake was so powerful [around 8.9 on the richter Scale] that, seven hours after the quake occurred, waves of between one and three metres gushed onto the shores of the islands in the Carribean (having receded by up to a kilometre from the shore of Martinique first) on the other side of the Atlantic Ocean. Large waves also hit North Africa (causing a large number of fatalities) as well as along the western shores of Europe [Devon and Cornwall in the south of Englandwere hit by 3 to 5 metre waves].
Ireland was also struck – there was damage caused to the harbour in Kinsale. Wikipedia mentions that the Spanish Arch in Galway was partially destroyed by high waves caused by the earthquake too, but I’m not sure if this is accurate. At the time, the entire Claddagh was a low-lying salt marsh populated with the cottages of local fishermen, and waves large enough to destroy the Arches would have caused devastation all along the shoreline. What’s more, another earthquake in 1761 in the Atlantic caused even larger waves to hit Ireland and agaon, Cork took the worst of it. But neither event is mentioned in Hardiman’s History of Galway, and in Phillip‘s “The Hundred Wonders of the World”, he mentions the damage done to Kinsale but does not specifically mention Galway [likewise this study on the 1761 quake only mentions damage done to Cork].
Could a tsunami hit Ireland today ? The British Geological Survey have a very interesting study which suggests that the chances are low which is good for me since I live by the sea.