Sound of beach waves 9 hours
The wave's crest usually hits shore about five minutes later. If the tsunami's trough reaches shore first, it sucks the water seaward, exposing the seafloor suddenly. It moved a 750-block of coral 1.5 miles (2.4 kilometers) closer to shore but did little other damage. In 1971 a wall of water 278 feet (84.7 meters) high surged past Ishigaki Island, Japan. Boaters are safer out at sea during a tsunami than close to shore or tied up at port. In the open ocean, the wave length of a tsunami is hundreds of miles long and only a few feet high. At that pace they can cross the entire expanse of the Pacific Ocean in less than a day. Tsunamis race across the sea at up to 500 miles (805 kilometers) an hour-about as fast as a jet airplane. In 2004 more than 200,000 people-the most ever recorded-died in an Indian Ocean tsunami that was triggered by an earthquake off Sumatra, Indonesia. Most tsunamis, about 80 percent, happen within the Pacific Ocean’s Ring of Fire, a geologically active area where tectonic shifts make volcanoes and earthquakes common. Many witnesses have described the sound of an approaching tsunami as being similar to a freight train's.
#Sound of beach waves 9 hours series
Our English word "tsunami" comes from the Japanese term for "harbor wave." Tsunamis are not the same things as tidal waves and actually consist of a series of waves. Tsunamis are usually generated by undersea earthquakes at tectonic plate boundaries, but they can also be triggered by underwater landslides, volcanic eruptions, or even a giant meteor impact with the ocean.Īn undersea earthquake creates a tsunami only if it is of sufficient force and there is a violent enough movement of the seafloor to displace a massive amount of water. Seawater suddenly retreats from the shore What is frequently a warning sign of an impending tsunami?Ĭ. Where was the largest tsunami in history recorded?ġ0. Can you detect a tsunami in the open ocean?ĩ. Up to 1,000 miles an hour (1,600 kilometers an hour)Ĩ. Up to 500 miles an hour (800 kilometers an hourĭ. Up to 200 miles an hour (320 kilometers an hour)Ĭ. Up to 100 miles an hour (160 kilometers an hour)ī. What is the deadliest tsunami ever recorded?Ī. Witnesses have said that an approaching tsunami sounds like what?Ħ. What does the word "tsunami" mean in Japanese?Ĥ. Do all undersea earthquakes trigger a tsunami?ģ. (Related: "Tsunami Warning for Hawaii After Huge Chile Earthquake.")Ģ. See how much you know about these walls of water ( tsunami safety tips). A tsunami can kill thousands of people and level entire blocks in mere seconds.