Cause and Effect: Harbor Wave
Alex Chin
Prof. Julianne Altenbernd
English 60
15 May 2014
Harbor Wave The earthquake that generated the great Indian Ocean tsunami of 2004 is estimated to have released the energy of 23,000 Hiroshima-type atomic bombs, according to the U.S. Geological Survey. The Indian Ocean tsunami traveled as much as 3,000 miles (nearly 5,000 kilometers) to Africa, arriving with sufficient force to kill people and destroy property. By the end of the day more than 150,000 people were dead or missing and millions more were homeless in 11 countries, making it perhaps the most destructive tsunami in history. Tsunamis are waves, or series of waves, created by a disturbance in the ocean. Tsunami means “harbor wave” in Japanese, reflecting Japan’s tsunami-prone history. There are many reasons for tsunamis. The first, and most common cause for tsunamis are abrupt movements on the ocean floor that can result from an earthquake. Tsunamis are most often caused when an earthquake causes the seafloor to rise or fall. Earthquakes happen when two tectonic plates collide into each other at a plate boundary. The denser plate is subducted under the other plate, which leads to a rise or fall of the sea floor. This movement of the seafloor will cause a rapid vertical displacement of water, and waves of a tsunami would form. As the wave approaches the coastline, it would get higher as the seafloor gets shallower, causing a tsunami to become visible and then grow even higher as the water gets more shallow. The shock waves produced by the earthquake would radiate out and cause other waves to form. The second reason for tsunamis are caused by volcanoes. There are two ways volcanoes can cause tsunamis. One possibility is for a land-based volcano to break down and collapse, forcing large amounts of ash and debris into the water. This sudden change and displacement of the water column transfers to kinetic energy and results in waves. More debris can create a bigger increase in wave amplitude
Prof. Julianne Altenbernd
English 60
15 May 2014
Harbor Wave The earthquake that generated the great Indian Ocean tsunami of 2004 is estimated to have released the energy of 23,000 Hiroshima-type atomic bombs, according to the U.S. Geological Survey. The Indian Ocean tsunami traveled as much as 3,000 miles (nearly 5,000 kilometers) to Africa, arriving with sufficient force to kill people and destroy property. By the end of the day more than 150,000 people were dead or missing and millions more were homeless in 11 countries, making it perhaps the most destructive tsunami in history. Tsunamis are waves, or series of waves, created by a disturbance in the ocean. Tsunami means “harbor wave” in Japanese, reflecting Japan’s tsunami-prone history. There are many reasons for tsunamis. The first, and most common cause for tsunamis are abrupt movements on the ocean floor that can result from an earthquake. Tsunamis are most often caused when an earthquake causes the seafloor to rise or fall. Earthquakes happen when two tectonic plates collide into each other at a plate boundary. The denser plate is subducted under the other plate, which leads to a rise or fall of the sea floor. This movement of the seafloor will cause a rapid vertical displacement of water, and waves of a tsunami would form. As the wave approaches the coastline, it would get higher as the seafloor gets shallower, causing a tsunami to become visible and then grow even higher as the water gets more shallow. The shock waves produced by the earthquake would radiate out and cause other waves to form. The second reason for tsunamis are caused by volcanoes. There are two ways volcanoes can cause tsunamis. One possibility is for a land-based volcano to break down and collapse, forcing large amounts of ash and debris into the water. This sudden change and displacement of the water column transfers to kinetic energy and results in waves. More debris can create a bigger increase in wave amplitude