This dataset is a model put run by the Pacific Marine Environmental Laboratory that simulates the waves of the December 26, 2004 tsunami during the first 54 hours after it occurred. A tsunami is a series of waves generated when a body of water, such as an ocean, is rapidly displaced on a massive scale. Historically tsunamis have been referred to as tidal waves, but that name is discouraged by oceanographers because tides have little effect on tsunamis. The bright areas indicate the wave crests while the dark areas are the wave troughs. The scale of this visualization is capped at 20 cm, which allows viewers to see the propagation of the wave across open water, however it should be noted that the wave heights were much higher in the shallower coastal waters.
The infamous Sumatra Tsunami on December 26, 2004, was the result of a massive earthquake that occurred when the India tectonic plate subducted beneath the Burma plate, causing an earthquake with a magnitude of at least 9.0 on the Richter scale. This displaced a huge amount of water. Out in the depths of the ocean, the wave heights do not increase dramatically. But as the waves travel inland, the depth of the ocean gets shallower causing the waves to build up. Waves with heights of 35.5 feet were reported during the Sumatra Tsunami. The speed of the waves depends on the ocean depth rather than the distance from the source of the wave. The waves travel faster over deep waters and slower over shallow waters as they build up. This allowed the Sumatra Tsunami to propagate worldwide in just one day. An estimated 230,000 people were killed as a result of the tsunami, 168,000 in Indonesia alone. One reason for the widespread devastation was the lack of a warning system. Previously thought unnecessary in the Indian Ocean because the last major tsunami was in 1883, efforts are underway by the NOAA Center for Tsunami Research to make a worldwide tsunami detection system a reality.