Tsunamis are caused mainly by powerful underwater earthquakes, but they can also be triggered by volcanic eruptions, landslides, or meteor impacts. In deep ocean water, tsunami waves can travel at jet-plane speeds while remaining almost unnoticeable. As they approach shallow coastal areas, the waves slow down, grow taller, and release immense energy, which is why the most severe damage happens near shorelines. Tsunamis are not single waves — they arrive as a series, and the first wave is not alw