How to Survive a Tsunami, According to Science

If you are caught in the tsunami, hold onto anything that floats, such as detached roofs, cars, or other large debris. The tsunami will carry a lot of dangerous debris, but some objects can offer a temporary refuge. The 2004 Indian Ocean tsunami saw a survivor hold onto a palm tree for five days.

Tsunamis are triggered by intense underwater activity like earthquakes or volcanic eruptions, displacing huge volumes of water. These events create powerful waves that grow stronger as they travel, reaching lengths of 100 kilometers and heights over 30 meters, moving at jet airplane speeds.

The first step to survival is recognizing early signs. Most tsunamis occur in the Pacific Ocean due to tectonic activity. An earthquake near the coast is a major warning. Another crucial sign is when the ocean water recedes significantly, exposing the sea floor. Do not investigate; instead, immediately move to higher ground.

When a tsunami is approaching, head inland opposite to the ocean, aiming for at least 3.5 kilometers away from the coast or 30 meters above sea level. If you can't reach high ground quickly, seek a tall building with a sturdy concrete foundation and get to the roof.

Remember that a tsunami is not a single wave but a series of waves, known as a tsunami wave train. Waves can be minutes to an hour apart, and the first wave is not always the strongest. Remain in a safe, elevated location until local officials declare it safe to return, even if you think the danger has passed.