Tsunami hazard assessment for the North East Atlantic

NE Atlantic tsunami hazard - summary of the tsunamigenic source potential
Potential tsunamigenic sources in the North East Atlantic (NEA) are assessed for a first screening of regional tsunami hazard, Figure 1. The study is performed within the framework of the EU project TRANSFER (Tsunami Risk And Strategies for the European Region). Both near-field and far-field sources are considered. An overview of past tsunami events in the region is revealed in Figure 2.

Based on modelling and evaluation of the corresponding tsunami scenarios, potential rock slides located in the fjords of Western Norway are considered the only high risk tsunamigenic sources in NEA (the fjords in Greenland are not investigated). Submarine landslides off the Norwegian continental margin, rock slides in Northern Norway, as well as earthquakes off the Portuguese coastline are identified as sources constituting moderate tsunami hazard. However, some of these sources should be investigated further.

Tsunamigenic earthquakes in the North Sea, the Norwegian Continental Margin, and the Norwegian-Greenland Sea are considered non-critical as the intraplate seismicity is low-to-intermediate, the active spreading zone does not produce tsunamigenic earthquakes, and there are few historical earthquakes above Mw6 (Bungum and Lindholm, 2007). Also the Jan Mayen and Iceland volcanic sources, the landslide sources north of Svalbard as well as the Grand Banks, Canary Islands, Cape Verde, and Caribbean far-field sources are considered non-critical with regard to tsunami hazard in NEA.

It should be noted that a proper classification of the tsunamigenic potential of the continental margins surrounding the northern North Atlantic and Arctic Ocean is difficult to assess, as important segments of these margins are not mapped in sufficient detail. This is particularly the case for the margins of the Arctic Ocean, but also for parts of the margins of Iceland, Greenland and Svalbard, and to a lesser degree the Barents Sea margin and some areas off Norway. 

Figure 1: Possible tsunamigenic sources assessed for the NE  Atlantic.	Figure 2: Past tsunami events with relevance for the NEA region. From the EU GITEC-TRANSFER tsunami catalogue.

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