Despite its storied and centuries-old past with earthquakes and tsunami, the nation of Japan (and the world) was mostly caught off guard by the ferocity, scope, and duration of the devastating natural calamities that struck on Friday, March 11th, 2011.

Without pause or waver, Mother Earth obeys the laws of planetary physics; the eternal placement and displacement of mass, spatial reaction countering every spatial action, the leveling and distribution of water, rock, and heat, and all the other rudimentary geophysical precepts.  And on random and terrifying occasion, she’ll enforce these laws with cataclysmic and often tragic results.

The northeastern regions of Japan are situated near the massive and craggy trench created by the convergence of the Asian and Pacific tectonic plate boundaries; part of the infamous volcanic “Pacific Ring of Fire”.  At this highly volatile juncture, what’s known to Geologists as a “subduction zone” occurs, as imperceptibly, the Pacific ocean plate grinds against and beneath the Asian continental plate in an agonizingly slow but eternal action, with bulges, cracks, and other surface irregularities alternately gnashing against and sticking to one another and creating immeasurable pressure on the submissive and downward curling continental plate edge.  The cumulative stresses on the rock are immense and can build for centuries before the compressed plate can no longer accommodate the overload.   To relieve itself of the burden, it reacts with a sudden, massive upward lunge of a gigantic section of the ocean floor along the rift (known as a megathrust) … and a powerful earthquake is born. These sections can be hundreds, if not thousands of miles in linear distance, and the entire column of seawater above it is displaced vertically, causing a series of seismic induced ocean waves, or tsunami.  Initially, they appear on the ocean’s surface as a monstrous circular or oblong bulge, radiating in a 360 degree series of wave trains that hurtle outward towards unsuspecting shorelines at speeds of up to 500mph. 

There are three common misunderstandings about tsunami:

1. Unlike typical storm created groundswell or localized wind driven surface swell, tsunami are triggered by abrupt geological events, not the wind, and they occupy the entire water column from surface to bottom.  So theoretically, a 3’ bump on the ocean’s surface could be added to the however-tall vertical band of energy beneath it.  This energy also causes tsunami to gain in height and/or volume as they near offshore land shoals.  As it encounters shallower depths nearer land, the water molecules are compressed and forced upward as needed, the wave face slows as the propagating volume at its back catches up, and often towering walls of water are formed.
    
2. Waves created by wind will form energy that is much shallower in depth as they pass through the ocean, and no water molecules actually move until the wave crests or breaks.  With tsunami, the entire ocean mass moves in union as the wave or waves are compressed near shore. Because they cannot swim against it, this is why sea life is often found deposited on shore.  Unlike wind waves, tsunami are often “backless” with no dissipation as the secondary waves overtake the ones in front of them and the ocean seeks its level, surging far inland, standing, and then retreating to its origin in deadly sequence. 
    
3. It’s impossible to accurately predict tsunami heights and inland reach.  The wave’s amplitudes and wavelengths are constantly changing throughout their travel distance as the wave passes over irregular bathymetry and depth.  And once it does arrive, the curvature and topography of coastal land can greatly affect the wave’s refraction and focus.  Refraction and wrap can also reach coastal areas facing opposite of the tsunami origination point with equal intensity.

In terms of magnitude, the 2011 Japan earthquake measured right up there with the 2004 Indian Ocean event, officially registering at 9.0 on the Richter scale.  It actually shifted the Earth off its axis, shortening daylight hours, relocating sections of land anywhere from 10’ -100’ further out to sea, and dropping others 2’ - 3’ under it.  It occurred at a depth of 4 miles below the surface, with many frighteningly strong aftershocks ensuing.  Even the size and ocean-wide distribution of the resulting tsunami were similar with mean wave heights estimated in the 33’ range in some locations. Both events sit comfortably within the list of top five most powerful in modern seismologic recordation.

Animation link: http://en.wikipedia.org/wiki/File:20110311Houshu.ogg

Although the unofficial death toll in Japan looks to be a fraction of its 2004 predecessor, the breadth of material destruction was far greater because of the denser, more modern and industrial development of Japan’s coastal areas, and more importantly, the presence of several high powered nuclear power plants that exist within.  The damage to these reactor facilities have global implications should one or more of them fail and meltdown. Already, highly concentrated radioactive materials have fouled the soil, sea, and food and water sources in nearby areas, and the big bangs haven’t even occurred yet.  Airborne fallout poses the first worry for residents of neighboring countries and Hawaii, as it gets swept up into the North Pacific jet stream to lightly dust vast areas of ocean and land with radioactive isotopes.  Ocean currents will disperse radiation leached debris and seawater as well.  At the time of this writing, the Japanese Nuclear and Industrial Safety Agency has assigned a severity rating to the nuclear accident at the Fukushima Dai-chi reactor facility at a Level 7 on the International Nuclear Event Scale.  This rating of Level 7 is the highest possible on that scale, and indicates an accident likely to cause widespread radioactive contamination with serious, long lived health and environmental effects. Prior to Fukushima, only the disastrous Chernobyl (in the current Ukraine) reactor explosion and meltdown received a Level 7 rating from the INES.  Human birth defects, animal mutations, increased cancer cases, and other afflictions plagued the people, wildlife, and natural resources within an 180,000 square mile radius around Chernobyl for years.  25 years later, the soil at ground zero still registers radioactive contamination.  Adding to the concern about Fukushima is the accuracy and integrity of reports coming from Japanese officials.  Japanese products, amongst the most technologically innovative, prolifically manufactured, and heavily consumed in the world, will be reduced significantly, affecting its market share and economy.  Unfortunately for Japan and its people, Godzilla does indeed exist, just not in the form of a stuntman wearing a cheap rubber lizard costume.

Relative to the perceived threat, the effects of the tsunami on Hawaii were moderate.  Although there was damage to harbors, moored boats, and some oceanfront properties, there was no loss of life reported, and the damage should be remediated quickly.  One possible exception being the low lying Northwest Hawaiian Islands from Midway down, where protected wildlife species suffered great losses of wildlife and habitat.  California may have incurred higher total estimated dollar damage mainly because of the sheer size of their coastline, but both locations got off rather easily based on the indicators that this event was the real deal for the entire Pacific theater.  In light of the “false alarm” it’s never a bad idea for Hawaii residents to run a real life live fire drill, in preparation for when, not if, the “Big One” does come.

As the chaos in Japan carries on, renewed concerns are rising about the next “Big One” setting up to the northeast of Hawaii, about 50 miles off the coast of the US Pacific Northwest.  The Cascadia Subduction Zone actually stretches from Vancouver Island, Canada, past Washington state and Oregon, on down to Mendicino, in Northern California.  With the Earth dealing out major seismic events off of Indonesia, Japan, and Chile in recent years, the world’s geologists and oceanographers turn their attention to the North American and Juan De Fuca plate convergence, where the looming Cascadia Subduction Zone discreetly goes about its menacing business … loading up for the next “Big One”. 

Although earthquake prediction is an inexact science at best, geologists had originally thought a major earthquake at Cascadia as being hundreds, possibly thousands of years off, based on past recorded patterns and guesstimates.  But that notion has now changed completely in response to the recent activity on the other side of the Pacific Ocean metaphorically calling for Cascadia to come out and play, and the scientific community’s collective consensus now is for a huge event of 9.0 magnitude or higher to rock the entire western US and Canadian coastal regions sometime within the next 50 years.  It would be followed by tsunami trains hundreds of feet high that could devastate major US cities such as Seattle, Portland, and possibly even San Francisco. Here’s to hoping Honolulu isn’t on that hit list when it happens.   On the geologic scale, 50 years is a mere tick on the clock.

Scientists say that although the chances are slightly more remote, other tsunami threats for Hawaii include a giant landslide off the western flank of the Mauna Loa volcano, where massive sections of unstable volcanic sediment could slide in unison into the ocean, or even worse, an asteroid airburst above or directly into the Pacific Ocean.  Both are nightmare scenarios that could create mega-tsunami hundreds, possibly thousands of feet high.  How rising sea levels figure into the equation is a whole ‘nother deal.

The Japanese tsunami images are horrific but riveting, the effects tragic, but cautionary.  My lifelong interest in natural sciences made the Japan incident (morbidly) fascinating for me from that standpoint, but with great empathy for the Japanese people, and concerned about what nature may have in store for my children and theirs. Unlike certain climatic issues, Mother Earth’s unpredictable geologic whims cannot be controlled by man and when/what she says happens, will happen.  So as we go about our various trivial human pursuits (like surfing ), the Earth moves beneath our feet, displaced is replaced, reactions offset actions, and water, rock, and heat seek their levels.

 

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Coming in May on Oceanic SURF Channel
 

• Oceanic SURF Channel presents a live broadcast of the 2011 Nike 6.0 Lowers Pro, May 3rd through 7th from Lower Trestles in San Clemente, California.  The Lowers Pro features a Men’s ASP Prime event as well as a 5-Star Pro Junior division with over a quarter million dollars in combined prize money on offer.  ASP world tour stalwarts and Nike 6.0 team riders Julian Wilson, Michel Bourez, Alejo Muniz, Carissa Moore and others will be surfing in this prestigious contest.  With springtime southwest swells beginning to pump into SoCal, the action’s going to be sick!
   
   

• Bus’ out da paddles, as Oceanic SURF Channel brings you a live broadcast of the 2011 Rainbow Sandals Gerry Lopez ‘Battle of the Paddle’ Hawaii, May 14th and 15th from beautiful Duke Kahanamoku Beach in Waikiki!  Hundreds of elite stand up paddle athletes from around the world will compete in this exciting championship styled surf race and contend for a piece of the $25,000 cash purse, the largest in the sport.  Pipeline legend and hardcore SUP enthusiast Gerry Lopez will be on hand for the event.
   
   

• “Ola Surfistas! Oceanic SURF Channel presents a delayed broadcast of the 2011 Billabong Rio Pro from exotic Rio De Janeiro in Brazil, May 11-22.  This is the third WT event on the ASP World Tour and offers over $600,000 in combined prize money for the world’s top male and female surfers!  Because of the 7 hour time zone difference, it will be shown in replay at a more convenient time for Oceanic digital customers.  Watch for announcements on Oceanic SURF Channel.”

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