Earthquakes and Hazards: Impacts and Responses
1. Types of Hazards
- A – Earthquake – It happens really fast and short, and will only affect a certain small area.
- B – Hurricane/Volcano – It lasts for a very days or weeks, and affect few areas.
2. Earthquake Distribution and Plate Tectonics
The distribution of earthquakes is affected by plate boundaries and plate tectonics. Plate boundaries are where two plates meet, and plate tectonics is the movement of the plates. An earthquake occurs along the boundaries of the tectonic plates that make up the earth’s crust. The most active region in the world corresponds to the margins of the Pacific Ocean. Earthquakes with large magnitudes take place along this zone in the Americas from the Aleutian Islands to southern Chile and from the Kamchatka peninsula in Asia to New Zealand. An earthquake occurs along divergent (constructive) plate margins. These margins include the mid-Atlantic ridge (between the South American plate and African plate and North American plate and Eurasian plate). At a constructive or divergent boundary, the plates move apart (tend to be found in the Mid-Atlantic ridge) (North America plate and Eurasian plate). At a destructive or convergent boundary, the plates move towards each other. (This usually involves a continental plate and an oceanic plate. The oceanic plate is denser than the continental plate, so as they move together, the oceanic plate is forced underneath the continental plate. The point at which this happens is called the subduction zone.) (Nazca and South America)
3. Hazards, Disasters, and Responses
Hazards and disasters always bring a huge impact. People cope with hazards in a number of ways. At 14:46 on Friday, March 11, 2011, Japan experienced a magnificent earthquake on the Pacific coast of Tōhoku. The earthquake was a magnitude of 9.0, which is the largest earthquake that has happened in Japan. This earthquake also provoked a 10-meter-high tsunami wave and destroyed many cities and villages. The tsunami also damaged three nuclear reactors, which caused a nuclear accident at the nuclear station and affected hundreds of thousands of people.
After the earthquake, Japan’s immediate response was to rescue people; this may involve the use of search and rescue teams and sniffer dogs. In the short-term response, rehabilitation and reconstruction will be the main focus. Also, providing aid money and burying the dead to stop the spread of diseases will be helpful in the short-term response. In the mid-term, the government should start rebuilding and reconnecting the water and electricity supplies, and slowly reopen hospitals and schools, and rebuild homes or shelters for people. In the long term, the government should restore the functions of public service and rebuild the public system, economic system, infrastructure, and government function to execute further response strategies. Japan has done well on the responses and is trying to reduce vulnerability through preparedness. The government has considered educating people on how to cope with earthquakes, such as hiding under a table. Also, governments can put laws and building codes in place to govern what can be built and to what standard, so that hazard impacts can be reduced. There are also a number of prediction methods that can be used to help assess the risk of an earthquake, such as measurement of small-scale ground surface changes and micro-earthquake activity. The government can subsidize science labs to promote scientists’ predictions on earthquakes.
Prevention – For example, Japan is now very prepared for the next earthquake through reconstructing buildings, such as building shear windows and building bases. Japan has experienced a massive nuclear accident, and the government has prepared well. Fully protective clothing was essential.
Requests for such visits had previously been refused on the grounds that radiation levels were simply too high and that the presence of visitors might limit the progress of the clearing-up operation.