Tsunami Essay

                  Tsunamis are among the magnificent natural phenomena that our planet is home to.  They are equal to the aurora, surpass thunder, and are just as grand as lightning.  Tsunamis can start out as small, 10-centimeter tall waves, that grow and grow in the ocean, until they reach awesome heights by the time they hit the shore.  The largest wave ever recorded hit Alaska, and was 1,720 feet high.  Tsunamis can create tremendous damage when they hit towns and cities, and they can kill thousands of animals and people all at once.  They can cause tons of economical disaster: millions of dollars needed to repair damage done to buildings, all the people that are out on the streets, homeless, might owe the bank sums of money that can’t be repaid, which makes banks lose tons of money, which could possibly lead to an economical crisis.  State parks could be destroyed, leading to a faster extinction of endangered animals.  The last person knowing a certain native language might pass away, leaving true understanding of that tongue impossible from now on, and much more.  These are some of the reasons why scientists try to predict tsunamis, and they have come up with a number of ways to anticipate them, and get people away before they hit.

Bottom Pressure Sensor

One of the most common ways of measuring tsunamis that scientists use is a bottom pressure sensor.  Because all tsunamis happen after an underwater earthquake, but they don’t happen every time after an underwater earthquake, many false alarms and hasty/expensive evacuations have happened.  Bottom pressure sensors are meant to go on the sea floor.  They can detect the slight pressures of baby tsunamis traveling above them, and are generally very reliable.  As the full tsunami really actually reaches its full amplitude once it’s reached the shore, it’s only about 10 cm out in the ocean.  Bottom sensors measure the pressure of the water, and they record whatever they feel and send their information to a nearby buoy.  The buoy then transmits this to a satellite, which gets it to a watch station with scientists who can sound the alarm if needed. 

There are both good and bad things with people using bottom pressure sensors.  First, they can be expensive.  Secondly, putting them under the water in the ocean can cause harm to the natural environment around them.  Consecutively, this could cause a chain reaction that could start out with either the lack of habitat or damaged habitat for a few species, and then spiral out to effect huge monsters such as the great white shark through the food chain.  If one species of animal decreases, the ones that eat it decreases, and then the ones that eats them die too.  Although using bottom pressure sensors could potentially cause big problems for many of the animals in their areas, they could also make possible homes for small fish, shrimp, and plants.  Algae could begin to grow on the bottom of the buoy and around the edges of the sensor, providing food for little fish, shrimp, crab, and other small, underwater creatures.  This could lead to a rise in these animal populations (which are mostly prey) and that, in turn, could lead to a rise in the secondary and tertiary consumers.  That whole ocean area would flourish for a while until the food begins to run out, when all species would start to decline in population numbers.  

According to scientists, you can also use GPS satellites to predict tsunamis.  Satellites can tell how much the earth in the ocean has actually been moved, and then geologists can use this information to determine whether or not there is a tsunami risk or not.  The GPS strategy works by scientists measuring the time signals from the satellites take to arrive at earthquake stations within a couple thousand kilometer radius of the quake itself.  That way, they can tell how much the stations have been moved by the earthquake, and then decide if there could be a potential tsunami.

The problem with the GPS satellites is that they can’t actually sense or measure a tsunami.  They can only tell whether or not there might be one.  However, because they can make scientists aware of the fact that a potential earthquake might occur, they are more alert and better prepared if there really is one.  Also, combined with the information from the bottom pressure sensors, the accuracy of the satellites might add an extra couple of minutes to evacuation, which could save many lives.

Another way people try to predict tsunamis is to trace an underwater earthquake to its epicenter.  Once you figure out where the epicenter of an earthquake is, you can determine where the tectonic plates pushed up to create a wave.  Then, you can decide whether or not your area is in tsunami range, and save your city.  The problem with this is that most underwater earthquakes do not create big waves.  Then, people evacuate the city for no reason.  It’s a big waste of time, money, and resources, and it doesn’t even work that well anyway.

How Tsunamis are Formed

Being able to detect tsunamis is important, because powerful tsunamis have the ability to knock down tall buildings and small homes alike, killing thousands of people and causing tons of expensive damage.  Supposedly, even a one minute warning can give people the time they need to get about a mile up to higher ground, which could mean the difference between life and death.  If a poorer country gets hit by a tsunami, it might not be able to pay for the damage done to its cities, and more people could die because of untreated injuries, or because they don’t have a roof over their heads, or food to eat.  The bottom sensors are able to detect tsunamis so accurately that they can give people hours of warning time, and people living along the West Coast in the United States of America may be evacuated after a warning from an earthquake all the way in the Cascadia fault.  With all the new ways of detecting tsunamis combined, everyone might have a better chance to survive these enormous waves.

Resources:

1.)    "Tsunami-recording in the Deep Sea." PhysOrg.com - Science News, Technology, Physics, Nanotechnology, Space Science, Earth Science, Medicine. Web. 22 Feb. 2011. <http://www.physorg.com/news114696029.html>.

2.)    "Savage Earth: Predicting Tsunamis." PBS: Public Broadcasting Service. Web. 22 Feb. 2011. <http://www.pbs.org/wnet/savageearth/tsunami/html/sidebar1.html>.

3.)    "Predicting Tsunamis — GEOL 105 Natural Hazards." A Class Blog on Current Hazard-related Events — GEOL 105 Natural Hazards. Web. 22 Feb. 2011. <http://geol105naturalhazards.voices.wooster.edu/predicting-tsunamis/>.

4.)    "NGI News Story -- Sep 18, 2010: FSU Researcher Deploys Bottom Sensors." Northern Gulf Institute. Web. 22 Feb. 2011. <http://www.northerngulfinstitute.org/news/fullstory.php?nid=351>.

5.)    "GPS Can Predict Tsunamis." Universe Today. Web. 22 Feb. 2011. <http://www.universetoday.com/199/gps-can-predict-tsunamis/>.