Although tsunamis occur frequently in the Caribbean, they are much 

 less frequent in the North Atlantic Ocean. The only major recorded 

 tsunami along the east coast of the United States and Canada was the 

 tsunami which devastated the Burin Peninsula along Placentia Bay, 

 Newfoundland, in November 1929. At least 26 lives were lost (Jaggar, 

 1929). The tsunami was enhanced by an exceptionally high tide and high 

 storm waves; otherwise, it may not have been of major proportions 

 (Hodgson and Doxsee, 1930). This tsunami was reported to have had a 

 height of 0.31 meter (1 foot) at Atlantic City, New Jersey (Murty and 

 Wigen, 1976). 



Stein, et al . (in preparation, 1980) report on earthquakes in eastern 

 Canada from Baffin Island to Newfoundland. For the 1929 Grand Banks 

 earthquake, which generated the tsunami, they give a magnitude of 7.2 

 as reported by Gutenberg and Richter (1965). Stein, et al . suggest that 

 the earthquakes in this area are associated with basement faults which 

 have been reactivated by the removal of Pleistocene glacial loads. 



Earthquakes frequently occur in the eastern United States. These 

 include a large earthquake that occurred in New England on 18 November 

 1755, shortly after the November 1755 earthquake near Lisbon, Portugal 

 (Reid, 1914), and the earthquake near Charleston, South Carolina, on 

 31 August 1886 (Taber, 1914). All of the earthquakes in the eastern 

 United States have occurred inland from the coastline. The probability 

 of an earthquake having an epicenter in a location that would cause a 

 tsunami, either on the coastline or in an estuary, cannot be determined 

 from available data. Brandsma, Divoky, and Hwang (1979) give probable 

 maximum waves for tsunamis at points near both the Atlantic and Pacific 

 coasts of the United States. Their results are based on mathematical 

 simulation of extreme events. 



The only tsunamis of record that traveled across the North Atlantic 

 were those generated near Lisbon, Portugal, in 1755 and 1761. Both of 

 these were recorded on the south coast of England, as well as in the 

 West Indies (Davison, 1936). For comparison, the 1755 tsunami had a 

 maximum rise of 2.4 meters (8 feet) at Penzance (England) and flowed over 

 the wharves and streets at Barbados (West Indies). In 1761, the sea rose 

 about 1.8 meters (6 feet) at Penzance and 1.2 meters (4 feet) at Barbados. 

 Other runup heights in 1755 were estimated at 4.9 meters (16 feet) on the 

 coast of Portugal, 18 meters (60 feet) at Cadiz (Spain), 1.8 meters (5.9 

 feet) at Gibralter, 15 meters (50 feet) at Tangier (Morocco), 5.6 meters 

 (18 feet) at Madeira, 14.6 meters (48 feet) at Faial (the Azores), 2.5 

 meters (8.2 feet) at St. Ives (England), 3.7 meters (12 feet) at Antigua 

 (West Indies) 6.4 meters (21 feet) at Saba (West Indies), and the waves 

 overflowed the lowlands on the coasts of Martinique and other French 

 islands . 



In general, good data are available for only a limited number of 

 tsunamis. A major gap in the data is tsunami heights in deep water. 

 Because of this gap, only limited verification is available for numer- 

 ical models for propagating tsunamis across large oceanic distances. 



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