Rogue Waves

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Rogue Waves
151 Final Presentation
Veronica Heintz
Definition
 Arise seemingly out of nowhere
 Significantly higher than any other waves in the
surrounding area
 The accepted ratio: 2-3:1
 Vastly different than Tsunami waves
 Tsunamis caused by earthquakes on the seafloor, not
visible on the surface of deep water
Myths?
 Until recently, rogue waves were thought to be just tall
tales of sailors
 No proof since they are so unpredictable
 “100 year waves” because of the probability of occurring
 New Year’s Day, 1995-Daupner Platform (North Sea) wave
height instrument was detecting waves ~ 5-7m (16-23ft),
and suddenly registered a single wave almost 20m (66f)
 2004- ESA used two satellites with radar to measure how
frequent rogue waves are
 Results: Analysis of images of worldwide oceans during a 3
week period showed 10 waves of 25m (82ft) or higher
Context
 8 feet- The height of the ceiling in an average room in your
house
 20-30 feet- The height of a typical two story house
 50 feet- The height of each letter in the “HOLLYWOOD”
sign
 111 feet- The height from of the Statue of Liberty from the
tip of her head to her feet.
Caught on Video
 http://www.youtube.com/watch?v=l_8hOai9hGQ
Causes: 3 Main Explanations
 Constructive Interference
 Swells pass through others and occasionally their crests
and troughs coincide and reinforce each other
Causes: 3 Main Explanations
 Strong Currents + Opposing Winds
 Ocean currents cause waves to "pile up" when waves
run into them head on
 Random currents and waves coming from more than
one direction can act like a lens, focusing the waves to
produce larger amplitude waves
 Gulf Stream (Bermuda Triangle), Agulhas current off the
coast of South Africa
Causes: 3 Main Explanations
 Nonlinear Effects of Water Waves
 Nonlinear water surface waves can be modeled after the nonlinear
Schrödinger equation
This equation is a classical field equation used to model plane waves (never
describes the evolution of a quantum state)
 Relation to optics
 Nonlinear effects in optical fibers are also modeled the same way: In
optical fibers, “the material properties are tuned to respond to the
intensity of the incoming light to create a self-focusing effect, balancing
the dispersive spreading of the light wave. This gives rise to optical
solitons, light pulses that can cross large distances in a fiber without
information loss” (5)
Take Away Message
This is an extremely fascinating phenomenon that
possibly explains countless tragedies through human
history. Research done to understand rogue waves and
where they come from has the potential to save lives!
References
 "Freak Waves." PBS. PBS, n.d. Web. 02 Dec. 2013.
http://www.pbs.org/wnet/savageseas/neptune-side-waves.html .
 "How Rogue Waves Work." HowStuffWorks. N.p., n.d. Web. 27 Nov. 2013.
http://science.howstuffworks.com/environmental/earth/oceanography/rogu
e-wave3.htm .
 "Monsters of the Deep." The Economist. N.p., 17 Sept. 2009. Web. 27 Nov.
2013. http://www.economist.com/node/14446734 .
 "Rogue Wave." Wikipedia. N.p., n.d. Web. 3 Dec. 2013.
<en.wikipedia.org/wiki/Rogue_wave>
 "Rogue Wave' Is Large, Unexpected, and Dangerous." What Is a Rogue
Wave? N.p., n.d. Web. 02 Dec. 2013.
http://oceanservice.noaa.gov/facts/roguewaves.html .
 "Rogue Wave Recreated in Laboratory Tank." PHYS.ORG. N.p., n.d. Web. 02
Dec. 2013. http://phys.org/news/2011-05-rogue-recreated-laboratorytank.html .
 "Rogue Waves." National Geographic Education. N.p., n.d. Web. 02 Dec. 2013.
http://education.nationalgeographic.com/education/news/roguewaves/?ar_a=1 .
 "Rogue Waves." What Is a Rogue Wave? NOAA, 11 Jan. 2013. Web. 02 Dec.
2013. <http://oceanservice.noaa.gov/facts/roguewaves.html>.
 "Viewpoint: Exciting Rogue Waves." Physics. APS Physics, n.d. Web. 02 Dec.
2013. http://physics.aps.org/articles/v2/86 .
 "What Causes Rogue Waves?" Focus Magazine. N.p., n.d. Web. 02 Dec. 2013.
http://sciencefocus.com/feature/environment/what-causes-rogue-waves.
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