- Introduction
- Opening Statement
- Thesis Statement: Tsunamis are waves formed due to heightened activity beneath the ocean floor, such as earthquakes, explosions and landslides, which foster huge displacements of water from the ocean surface.
- Tsunami
- Tsunamis and its Causes
- Characteristics of Tsunamis
- Conclusion
- Preparing for Tsunamis
- Conclusion
Tsunamis
It has been almost two years since the 2011 Tohoku earthquake and tsunami disaster, which made millions weary of the destructive power of tsunamis as it struck Northern Japan powerless. The tsunami did not just render the region powerless, but it had also opened up questions as to what tsunamis are capable of and how exactly these massive waves develop. With the rarity that comes with tsunamis, many are unaware as to why they exist and how they become so powerful in a short period of time. While disasters that come with tsunamis could be prevented with several disaster management strategies, many often confuse tsunamis with tidal waves. Tsunamis are waves formed due to heightened activity beneath the ocean floor, such as earthquakes, explosions and landslides, which foster huge displacements of water from the ocean surface.
While some often mistaken tsunamis as tidal waves, tsunamis are actually endless cycles of onrushing tides that has the capacity to force its way around land despite the obstacles. Normally, the damage is due to the amount of water tsunamis often carry, capable of pulverizing objects in each tsunami wave. Large objects such as ships and buildings would be carried inland, several miles away from its original location. A tsunami’s characteristics also tend to vary depending on the cause of the wave. If it is generated by landslides, the tsunami’s waves would be dependent on the amount of land that moved downslope and how fast it slide. Tsunamis from submarine landslides are different from the usual tsunamis as it moves materials in one direction, making the wave move off-shore parallel from the original direction of the slide. Tsunamis of this cause also are noted to have wave shapes as compared to earthquake-induced displacements. The first wave often shapes into a small crest, which is then followed by a deep trough that could be deeper than the original wave. The succeeding waves would have varying height differences. Slide-induced tsunamis also have varying wavelengths, ranging from 0.5-6 miles and happen from 1 to 5 minutes in intervals. For submarine landslides, they rarely move faster than 50 meters per second, however, its waves could accelerate up to 325-650 feet per second. Tsunamis tend to feel a friction from the ocean’s seabed, normally causing it to be refracted throughout the world seas. Upon hitting shallow water, tsunamis tend to slow down in velocity, pushing the first waves faster inland. Their destructive capacity tends to vary, given the location of land and its cause. In coastal areas, tsunamis move at 22 miles per hour. In shorelines, tsunamis can have the destructive power that could span up to 50-70 miles wide, moving similar to a car or train. Notably, tsunamis, due to its long wavelength waves, tend to stay high and move inward for roughly 30-60 minutes before simmering down. Normally, tsunamis could happen six to seven times on various time frames, considerably its succeeding waves are taller than the first waves .
With the Tohoku tragedy still fresh in the minds of the people, the public is now slowly being taught of tips on how to identify tsunamis and its signs. Three basic signs are noted by experts in whom a tsunami is possible to develop. The first warning to consider is tremors near a beach, which may be caused by an earthquake and tell-tale sign of an incoming tsunami. The second warning when it comes to tsunami identification is if the ocean suddenly pulls away from the coast or shoreline, showing the seabed. Finally, tsunamis comprise several waves with one hour intervals, which is why if one wave is done, a second or third wave may follow . Governments and organizations, especially those located in tsunami prone areas are now being taught of tsunami disaster drills to ensure they would immediately evacuate upon the first warnings of the government. In the United States, for instance, hazard maps and evacuation areas are now noted around the country in case of tsunami warnings. Several new technologies such as real-time deep-ocean tsunami detectors and satellite transmission are now used to determine signals from the seabed or underground for possible tsunami development . It is essential to maintain constant vigilance and remain calm especially if the warning is issued by the public. While the damage to property and the power of tsunamis could foster years of restoration and recovery, the lives that could be saved with proper tsunami awareness and preparation could immensely make a difference.
Works Cited
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