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Final Hazards Report

Being in such a high activity location, Japan has encountered some form of almost every disaster we have studied in this course. Being on the ring of fire, Japan's seismicity is a major focus as it contributes to a majority of their disasters. Japan is located at an intersection between four tectonic plates:   the Eurasian Plate, the North American Plate, Pacific Plate, and the Philippine Plate. All four of these boundaries are convergent which we all know indicates that the area will experience high earthquake activity and explosive volcanos. This busy intersection of tectonic plates is what leads it to so many disasters because with every shift of the plate, the entire island is at mercy. With that being said, earthquakes are Japan's primary hazard. This small archipelago withstands over 20% of the planets recorded earthquakes, averaging at 7-8 major quakes per decade. Additionally, being surrounded by water, with every slip of a plate, there is a literal ripple effect. The

Japan's Coastline

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Japan has a strong relationship to its coastline. Considering 70% of the archipelago is the uninhabitable forested mountain, much of the culture is drawn towards the coastline. To successfully live in the area, the Japanese are in tune to its behavior. Climate Change has created the largest change in Japanese coastlines, affecting the safety of those living around them. While money is also being invested in reversing climate change, protecting those from the inevitable increased weather disasters is equally important. This was further prompted by the 2011 Tohoku earthquake and following tsunami. It has taken years to repair the damage and one of the biggest investments in reinforcing the coastlines was building Tetrapods. "four-footed, porous, concrete 'breakwater barrier' used to prevent erosion and water damage by dissipating waves," Tetrapods are 10 tons each and are built a stones throw away from the real coastline to absorb most of the impacts caused by wave

Japan's Extreme Weather

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Japan's most recent bought of extreme weather came over the summer during disastrous rainfall. As the country was still recovering from late June's Typhoon Prapiroon, the atmosphere was too. That, combined with a warm front forming from the Pacific Ocean fed torrential storms across the country for a majority of July. This extreme weather created one of the country's most deadly summers resulting in record-breaking heatwaves (Record 106ยช F with 80 deaths from that alone) flooding, landslides, and 176 deaths. Japanese weather disaster experts claim that the country is experiencing significantly more extreme weather events as global warming rises. Because of the country's almost constant-feeling amount of earthquakes, the government tends to allocate funds toward building codes and reinforcing buildings to withstand quakes but not necessarily the increased flooding. Record-Breaking Temperatures compared to cities' previous records, all recorded July 23 Though we

Mass Wastings in Japan

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As the book says, slopes are the world's most common landform and Japan is no exception.  Being composed of 70% slopes, Japan experiences mass wastings usually following high rains. Water is a major cause for mass wastings by eroding slope bases, increasing the driving forces for a landslide, as well as increase the weight and underground water pressure of the earth material which, in turn, reduces resistance to slow a landslide as it descends. As with citizen knowledge and preparations for other disasters, Japan has a heightened awareness for mass wastings that has been unfortunately raised by first negatively experiencing destructive landslides. The preemptive landslides from four years ago helped to create warning systems and plans that saved lives from this last summer's onset of monsoon-induced landslides. On August 20, 2014, Hiroshima in particular experienced terrible, deadly landslides following a rainy summer season, where over 400 residential homes were buried and 7

Japan's Volcanic Activity

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Like earthquakes, Japan is in a prime location on the Ring of Fire to experience many of the world's volcanic activity. As previously noted, Japan is located between four different convergent tectonic plates resulting in general high tectonic activity. Being located on a subduction zone, where one plate dives beneath the other into the asthenosphere, the plate melts and fuels volcanic eruptions. The subduction zone of the Pacific plate diving below the Eurasian plate creates a volcanic arc along the islands of Japan. This image from Earthguide illustrates the relationship between the subduction zone (blue lines with arrows) and Japan's volcanos (white triangles). With 110 active volcanos in Japan, the Japan Meteorological Agency has created a leveled classification system to illustrate the hazards of the nation's many volcanos. Like earthquakes, Volcanic eruptions cannot necessarily be predicted, however, because they show more visible activity, countries with high ac

Japan's Seismicity and Disaster Preparedness

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With an average of one magnitude 7-8 earthquake occurring per decade, Japan experiences some of the highest rates of seismic activity in the world, around 20% of recorded earthquakes worldwide. As a result, Japan is arguably the world leader in disaster preparedness. Every > 7.4 magnitude earthquake along the Okhotsk/Pacific subduction zone from 1896-2010 which set precedent for earthquake and tsunami warnings across the country's coastlines. One of Japan's subduction zones, where the oceanic Pacific Plate dives below the continental Okhotsk plate (I previously named this the North American Plate), earthquakes are concentrated up to 70 km deep, meaning that the many "Megathrust" earthquakes occur and often also create Tsunamis. The 2011 Tohoku Earthquake and subsequent tsunami was one of these occurrences. 2011 Tohoku Earthquake This "Megathrust" quake was caused by convergent tension building up for centuries until the Okhotsk plate sprang

Japan's Proximity to Tectonic Plates

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Japan is located at an intersection of four tectonic plates, part of the hotspot known as The Ring Of Fire. The plates in clockwise order are the Eurasian Plate (shaded green), the North American Plate (red), Pacific Plate (Yellow), and the Philippine Plate (purple) The boundaries of all four plates surrounding Japan are convergent, meaning that the two plates push together which results in higher occurrences of earthquakes and explosive volcanoes. These particular plates are subduction zones, where one plate moves below the other plate into the Asthenosphere. As the plate is dragged down by gravity, the mantle melts the rock down into liquid magma which rises back up and leads to volcanic activity. Volcanic Activity Earthquake Activity Subduction Zones Images are taken from: http://education.maps.arcgis.com/home/webmap/viewer.html?layers=69cb1f185afa47528708dbaa89e0729b&useExisting=1  (Image 1) http://earthguide.ucsd.edu/eoc/teachers/t_tectonics/p