Tsunamis: The Most Destructive Force of Nature

Tsunamis, or harbor waves, can be a very destructive force of nature. An earthquake, undersea volcano, an asteroid crashing into the ocean or a landslide normally causes tsunamis. Most tsunamis originate near the Ring of Fire, a chain of volcanoes in the Pacific Ocean. From 1819, Hawaii had around 40 tsunamis!

Tsunamis wavelengths are around 100km-200km. Tsunamis travel hundreds of kilometers from the ocean to the harbor at speeds of 725km-800km per hour. Tsunamis are a series of waves, and in the deep ocean, the wave is only half a meter high. When they go near the coast, they go as high as 30m! Tsunamis can take a form of a very fast tide or a bore. Tsunamis are so powerful because of the weight. Around one square meter of water in a tsunami is around one tonne(a metric ton). When the wave is near the coast, it weighs millions and millions of tonnes. Tsunamis are often called tidal waves since gravity and weather has no effect on it.

Tsunamis are really hard to predict. Even if you try to use seismometers to predict an earthquake, earthquakes might not produce tsunamis and there are other things that cause an earthquake. In 1949, the Pacific Tsunami Warning Center was made in Hawaii. This program issued the five main tsunamis warnings, but it had fifteen false alarms. The Pacific Marine Environmental Laboratory developed the first accurate tsunami detector called the tsunameter. This measures the changes in water pressure when a tsunami passes. These are put on the ocean floor. When it detects a tsunami, it sends a wave to the nearest buoy. The buoy converts the wave to a radio wave and sends it to the nearest satellite. The satellite sends a radio wave to the warning stations like Pacific Tsunami Warning Center and West Coast Tsunami Warning Center. This whole process takes only two minutes. There are currently six of these in the Pacific Ocean. This is known as Deep-ocean Assessment and Reporting of Tsunamis (DART), but not all oceans have it yet.

The worst tsunami ever was in 2004, and the earthquake that caused it had a nine on the Richter scale. It hit the coast of Sumatra (an Indonesian island), and the coast of fourteen other southwest Asian countries. The Red Cross estimated around 250,000 people died. Most of the damage was in India, Thailand, and Sri Lanka. Tsunamis also killed 60,000 people 1755 in Portugal, Spain, and Morocco. This was recorded as the second worst Tsunami ever. Tsunamis are powerful, deadly and stoppable.

Sources: "Tsunamis." Wikipedia