A tsunami is a series of powerful ocean waves caused by the sudden displacement of a large volume of water, usually triggered by underwater earthquakes, volcanic eruptions, landslides, or even meteorite impacts.
Key Characteristics
- The word "tsunami" comes from Japanese, meaning "harbor wave," and refers to the waves' notorious impact on coastal areas.
- Tsunamis can travel across entire ocean basins at speeds up to 800 kilometers per hour (about 500 miles per hour) in deep water.
- While out at sea, tsunami waves are usually not very tall and may go unnoticed, but as they approach shallow coastal areas, their height increases dramatically, sometimes reaching up to 30 meters (almost 100 feet).
Causes
- Most tsunamis are caused by seismic activity such as underwater or coastal earthquakes.
- Other causes include volcanic eruptions, underwater landslides, and rare events like large meteorite impacts.
Effects
- When a tsunami reaches the shore, it can cause catastrophic flooding, destroy coastal infrastructure, uproot trees, and carry debris far inland.
- After the initial wave, multiple waves can arrive minutes to hours apart, often causing additional destruction as water flows inland and recedes back to the sea.
A tsunami is therefore not just a single large wave, but a complex, multi-wave event that poses significant danger to coastal communities and infrastructure.
