Respond to each post in 150 words or more.1 of 2Class, Tsuna

Respond to each post in 150 words or more.1 of 2Class, Tsunamis are caused by underwater earthquakes. A tsunami is a series of ocean waves that sends surges of water, sometimes reaching heights of over 100 feet (30.5 meters), onto land. These walls of water can cause widespread destruction when they crash ashore (Tsunamis. 2017, April 27). What causes a Tsunami? The tectonic plates shift and when the ocean floor plate moves it rises and falls suddenly. This causes a displacement in the water above it and launches the rolling waves that will become a tsunami. The way a Tsunami warning system works is by two sources, a distant source and a local source. A local source is when you feel a violent shaking for several minutes, head for higher ground. The earthquake is your warning. A distant source The perimeter of the Pacific Ocean Basin, nicknamed the Ring of Fire, has a number of earthquake sources that can produce strong earthquakes of 7.0 magnitude or greater. During the 20th century, there were three 9.0 magnitude or greater quakes, the last was the 1964 Alaskan quake of 9.2 magnitude that produced a tsunami throughout the Pacific Basin. These kind of earthquakes permit a lead time of hours before their subsequent tsunami reaches the Washington coastline. Tsunamis from distant locations like Japan or Chile will take over 10 hours to get here, while from Alaska, only three to six hours (N. n.d.). The real purpose for this warning system that is issued by the National Tsunami Warning Center is to help minimize loss of life and property.JonResourcesN. (n.d.). How does the Tsunami Warning System work? Retrieved May 01, 2017, from http://www.tsunami.noaa.gov/warning_system_works.htmlTsunamis. (2017, April 27). Retrieved May 01, 2017, from http://www.nationalgeographic.com/environment/natu…2 of 2Tsunamis are caused by major disturbances in the ocean and earthquakes are the most common cause. When an earthquake occurs, it can cause a shift in the ocean floor which causes the water to displace and form a wave. The formed waves can travel in different directions form the original source of the disturbance. The depth of the ocean controls the speed of the waves. As a wave gets closer to shore, and the depth decreases, the wave slows down. This allows the waves behind it to potentially catch up and increase the height of the first wave. ‘Tsunamis increase in height as they go over gradual, long slopes’ (Ismail, 2017). Tsunamis can be detected by DART (Deep-ocean Assessment and Reporting of Tsunami) systems, which are buoys that record the sea level changes in the deep ocean. There are typically two components, ‘the pressure sensor anchored to the sea floor and the surface buoy’ (Deep ocean, 2017). They measure changes in the height of the water column and water pressure. This data is relayed via satellite to the tsunami warning center. The DART system can predict speed and direction effectively, but not the height of the formed waves. These detection systems are not effective if an earthquake occurs close to shore. These potential tsunamis can form and hit land within minutes, leaving no time for warning or evacuation. In 2011, a 9.0 magnitude earthquake hit off the coast of Japan and formed tsunami waves. ‘In the first 30 minutes, a 40m high wave hit the coast, followed by 9 additional waves up to 10m in height’ (Ismail, 2017). The effects were devastating, including a nuclear meltdown in the Fukushima Daiichi Neclear Power Plant. ReferencesDeep Ocean Tsunami Detection Buoys. (n.d.). Retrieved May 02, 2017, from http://www.bom.gov.au/tsunami/about/detection_buoy…Ismail, A., & Z. H. (2017, April 07). The Science behind Tsunamis. Retrieved May 02, 2017, from https://ysjournal.com/the-science-behind-tsunamis/