Cumbre Vieja Tsunami Hazard
The island of La Palma in the Canary Islands is at risk of undergoing a large landslide, which could cause a tsunami in the Atlantic Ocean. Volcanic islands and volcanoes on land frequently undergo large landslides/collapses, which have been documented in Hawaii for example. A recent example is Anak Krakatau, which collapsed to cause the 2018 Sunda Strait tsunami.

Steven N. Ward and Simon Day in a 2001 research article proposed that a Holocene change in the eruptive activity of Cumbre Vieja volcano and a fracture on the volcano that formed during an eruption in 1949 may be the prelude to a giant collapse. They estimated that such a collapse could cause tsunamis across the entire North Atlantic and severely impact countries as far away as North America.

Model by Ward and Day 2001
The authors used linear wave theory to estimate the tsunami induced by the simulated Cumbre Vieja.[36] They used a scenario of a collapse of 500 cubic kilometres (120 cu mi) that moves at a rate of about 100 metres per second on top of a layer of mud or landslide breccia, which lubricate its movement, and eventually spreads 60 kilometres to cover a jug-shaped area of 3,500 square kilometres. Ignoring that the landslide excavates part of the flank of Cumbre Vieja, thus assuming that it does not contribute to any tsunami generation, they estimated the following timing of the tsunami:

- 2 Minutes: A 900 metres thick dome of water rises above the landslide.
- 5 Minutes: The dome collapses to a height of 500 metres as it advances by 50 kilometres; additionally, wave valleys form.
- 10 Minutes: The landslide is now over. Waves reaching heights of 400–600 metres hit the three western Canary Islands.
- 15–60 Minutes: 50–100 metres high waves hit Africa. A 500 kilometres (310 mi) wide train of waves advances across the Atlantic.
- 3–6 Hours: The waves hit South America and Newfoundland, reaching heights of 15–20 metres and 10 metres, respectively. Spain and England are partially protected by La Palma, thus tsunami waves there only reach 5–7 metres.
- 9 Hours: Waves 20–25 metres approach Florida; they are not expected to grow farther as they hit the coast.

France and the Iberian Peninsula would be affected as well. Further, the authors concluded that the size of the tsunami roughly scales with the product of the landslide speed and its volume. They suggested that traces of past such tsunamis may be found in the southeastern United States, on the continental shelf, in northeast Brazil, in the Bahamas, western Africa.

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