Tsunami is the Japanese word for a phenomenon often called a tidal wave. In fact the two are quite distinct. (Tsu means harbour and nami a wave.)

A tidal wave occurs when the rising tide forces a mass of water along a narrow estuary or strait, causing a rise in water level. The tsunami is much more destructive. The usual cause of a tsunami is an earthquake or similar event.

The largest tsunami yet measured was 85 m (270 ft) tall and appeared off Ishigaki Island, east of Taiwan in 1971. Far more destructive was the tsunami which swept through Indonesia on 27 August, 1883. When the island volcano of Krakatoa exploded that morning it not only blew itself to pieces but created a huge tsunami. As it swamped the surrounding islands, the wave destroyed 163 villages, killed 36,380 people and carried a warship miles inland. The height of this massive wave is unknown. Fortunately such tsunamis are rare.
Tsunami is one of the myriad flavors of SoBe on the market.

The flavor is orange cream and is akin to drinking liquefied 50/50 bars. Divine.

The bottle is a nice 20 fluid ounces and has lizards on the neck. The cap, which has a high likelihood of being difficult to remove due to problems at the SoBe Beverages bottling plants, is black and has a slogan on the inside.

The blurb on the back of the bottle states that it is: An energizing orange cream brew that will keep you up when the surf is up. Created by SoBe to celebrate surfing and the lizards who ride the big ones.


filtered water, high fructose corn syrup, skim milk, sugar, cream, pectin, citric acid, natural flavor, ascorbic acid (vitamin C), lactic acid, gum arabic, taurine, cochineal (color), zinc picolinate, niacinamide, calcium pantothenate, alph-tocopheryl acetate, ester gum, guarana extrat, cyanocobalamin, caramel color, pyridoxine hydrochloride, retinol palmitate

Nutritional information lists the serving size as being only 2/5 of the bottle. Typical.

Owned by the South Beach Beverage Company, all of the SoBe drink line proclaim their natural ingredients and herbal goodness.

Tsunamis endanger communities all along the Pacific Rim, and can be caused by local earthquakes or ones thousands of miles across the ocean. Tsunamis are relatively common in Japan and thus studied intensely there, but the west coast of the United States is also subject to major damage and many deaths from Tsunamis.

The most recent significant Tsunami to hit the west coast was in 1964, following the earthquake in Alaska. Of the 131 deaths caused by that quake, 119 were blamed on tsunamis, and 16 of those deaths were in California and Oregon.

Tsunamis often are the cause of more of the deaths associated with a coastal earthquake than the actual shaking. For example, the "big one" in the Northwest of the US, a predicted catastrophic quake of approximately 9.0 magnitude, is anticipated to kill 2,000 on ground in Oregon, but to kill 3,000 along the Oregon coast due to tsunamis. (I was unable to find parallel statistics for Washington state, but I imagine they would be similar.)

In recent years, state governments along the West Coast have been preparing for tsunamis, in hopes of mitigating the risk. A 1995 Oregon law mandated that no new public service buildings, such as fire stations, schools, or hospitals be built in low-lying coastal areas subject to tsunamis. As part of compliance with this law, maps of the Oregon Coast were drawn with a line at the edge of the tsunami inundation zone. Such maps not only aid in planning the locations of service buildings, but also are distributed to citizens to help them prepare for a tsunami event.

Standardized Tsunami Evacuation Route signs can now be found along the Alaska, British Columbia, Washington, Oregon, California, and Hawaii coasts, guiding the best way to high ground. Pictures of these signs can be found at http://pdxcb.net/gallery/manzanita?page=4 (these pictures are ones I took in Manzanita, Oregon.) The sign was designed in 1994 by an artist at Oregon State University, and the sign was adopted in 1997 by the Tsunami Hazard Mitigation Federal/State Steering Group for use along all Pacific states of the U.S.

Tsunami Warning systems are now in place along the Oregon Coast. In the event of a large earthquake in the Pacific Ocean or any significant motion felt in Oregon, a tsunami warning is issued and tsunami alert sirens are activated. All people are then evacuated to above the inundation line. The recently developed Deep Ocean Assessment and Reporting of Tsunamis system helps in detecting and evaluating tsunamis of distant origin in order to decide whether to activate warning systems.

This system was activated along the Oregon Coast due to the heavy shaking felt during the 2001 Seattle Earthquake (Nisqually Earthquake), and schools were immediately evacuated. Upon feeling any ground motion, all coastal residents should immediately evacuate. Should it became clear that there is no risk of tsunami from a particular event (as was the case with the 2001 quake), the warnings will be canceled and evacuees returned.

The most deadly tsunami on record was caused by a magnitude 9.0 earthquake off the coast of Sumatra, resulting in the deaths of at least 155,000 people.

Tsunami is an indie-rock band from Arlington, VA. They haven't played a show or released anything since 1998, but are supposedly still together. Their music isn't really pop, although a couple of their songs might be described as such. Lots of interesting guitar work and vocals courtesy of Jenny Toomey and Kristin Thomson, the founding members of Tsunami (and the only two founders still in the band).

Toomey and Thomson also founded the Simple Machines record label, home of the Mechanic's Guide on how to start a record label. Toomey can often be found these days writing articles for Insound, which is also where the current Mechanic's Guide resides.

Deep End, 1993
The Heart's Tremolo, 1994
World Tour & Other Destinations, 1995
A Brilliant Mistake, 1997
A whole lot of 7" singles and compilation appearances, most of which are out of print, but can be found on the World Tour CD/LP.

Hollywood has no idea

Hollywood's idea of a tidal wave is a giant surfing wave, towering above a calm, sun-drenched ocean: a curling, towering wall of water crashing in on a beach or city, destroying buildings and people with the crushing force of a million-tonne deluge. The movie directors seem to tell us that the destruction all happens in those first few seconds of impact. Perhaps you have a similarly vivid impression of what a tsunami might look like as it makes landfall. I know I did.

The reality--as shown by amateur video camera footage of the December 2004 tsunami in Asia--is much more mundane and in many ways, more terrifying. The sun shines just as brightly as Tinseltown would have us believe, but the towering crest of white horses is, in reality, a muddy, maelstrom of churning debris.

Utter destruction is heralded only by a small trickle of water, pushing its way up from the shoreline; creeping up the street; tumbling into potholes, cleaning the dust and sand from your toes. It looks inconsequential. A puddle you can step over or walk through. But 50 metres closer to the shore, the centimetre-deep trickle has grown to a malevolent torrent, stampeding up the beach like a runaway roadtrain.

Anyone who has stood waist-deep in a fast-flowing river knows how hard it is to remain upright. Now imagine that same river completely full with debris--sheets of corrugated iron, trees, cars, boats. The tsunami wave travels faster than most river currents, but surging water is not the biggest danger. The danger comes from the trees and cars and metal sheets boiling at the front of the onrushing ocean.

Within seconds of that small trickle washing away the dust, the water is two, three, ten metres deep and it is carrying all the metal, wood and machinery it has snatched from the shanty towns during its unstoppable surge from the ocean. It is churning along like some infernal grinding machine, ramming tree trunks into cars; hurling cars into houses and sheets of metal into the people--the bodies--being carried along at the front of the wave.

Watching the video footage I could not imagine how anyone who faced that water could ever survive. Strong swimmer or child, anyone caught at the front of the wave had no chance against the rolling, churning mass of metal and wood.

But the wavefront is just the start of the destruction.

Those of us with warped minds sometimes fantasise about swimming through a Hollywood tsunami-- a wall of clean water just a few times bigger than the breakers we have played in during a beachside holiday. Yes you feel the power of the wave. Yes you tumble and roll out of control, but if you curl up in a ball, hold your breath for a few seconds, then the wave will pass and you can bob up into open water, with time enough to fill your lungs before the next wave comes along. It's fun. Like bungee jumping, or riding a fast motorcycle. Adrenaline, self-control, skill. Thrill.

We have no idea

Oceanographers talk about wavelength. Tsunami are caused by large changes in the shape of the seabed. An earthquake causes a mountain of rock and silt to slump down, and water flows into the hole created, or away from the new mountain. It is a bit like dropping a huge stone into the ocean. The earthquake and subsequent slump will create ripples radiating out from the epicentre. Giant-sized ripples of water surging up and down. The specialists use their computers to work out the wavelength (from one peak to the next), speed (1000 km/hour) and energy (10 atom bombs) contained in those waves. Out in the ocean, those computers say, the wavelengths are around 100km. Closer to the shore the waves bunch up, and the waves are only 10 km or so from peak to peak.

If adjacent peaks are 10 km apart, the breaking wave is made up of the wavefront, followed by another five km--three miles--of water rushing in behind the initial surge. Imagine that wave front, carrying its debris and trees and bodies, pushed onward by another 5km of water behind it. By the time the wavefront has rushed past the former shoreline, it is probably travelling at 20 km/hour (5 m/sec)**. An Olympic sprinter could outrun that wave. I'm not sure I could, even with no-one else in the way, or calling for help. At that speed, a 5km-long wave will take 15 minutes to pass by. The in-rushing torrent of water keeps on coming for 10, 15 or 20 minutes.

** It seems that the December 2004 tsunami arrived in some parts of Sri Lanka at over 200 km/hour. Sri Lanka is unprotected by large continental shelves of shallow water. Shallow water slows the wave. You couldn't even outrun that in a car, let alone on foot.

And then drains away.

A cubic metre of water weighs a tonne, so a 5km-long wave, by 10m deep (a conservative estimate) means each metre of coastline sees 50 000 tonnes of water passing by. Twice. Inland and then out again.

Remember those ripples? It's not just one wave, but two or three, surging in; sweeping out. Search the Scuba community on the web, and you will find plenty of stories of scuba divers diving off coral atolls as the waves passed them by. They survived; their boats survived, because the wave had not built up in shallow water, but one diver described being pushed ever downwards then sucked up again two or three times, as subsequent waves passed his dive site. He later returned to shore, to find his holiday island destroyed, but, in a miracle of luck, his wife alive and well.

Eye witness accounts from Sri Lanka, Indonesia, Thailand and elsewhere talk of a second wave coming in twenty or thirty minutes after the first. Sometimes the second wave was bigger, sometimes smaller. Imagine: you just survived the worst experience of your life, and then you see it happening again. Nightmare.

Tsunami -v- ordinary waves: the differences

The first, and most obvious difference between a tsunami and a conventional ocean wave is in the amount of water involved. Ordinary waves are created largely by wind action. As winds flow across the ocean surface, they cause humps and bumps in the surface of the water. While these can appear big--a few tens of metres, for example--they exist only in the surface layers of the ocean. As you submerge below the ocean surface, the water becomes calm, unaffected by the turmoil above. Estimates vary for the overall volume of water involved in the biggest wind-borne waves, but the biggest estimate I have seen for a George Clooney-style wave is that it affects only the top 100 metres of water in the ocean. Below that depth, there are no significant pressure changes, even in the worst open-ocean storms.

A tsunami wave, by comparison, extends from the ocean floor to the surface. While the surface manifestation might show only a metre or two increase in water height, this represents a column of water a kilometre or two high, and each wave extends for tens of kilometres in terms of spread across the ocean surface.

If the biggest conventional wave has a wavelength of 200m and affects the top 100m of ocean depth, then it involves about 20 000 m3 of water per metre of wave front.

Contrast that with a small tsunami reaching all the way to the bottom of a 2 km-deep ocean, and extending for 100 km in length. (these are typical figures, but almost certainly under-estimate the recent Indonesian waves). The equivalent figure is not 20 000, but 200 million. So the mass of water involved is four orders of magnitude greater than the biggest conventional wave you can imagine. Furthermore, a tsunami wave travels faster through the water than conventional waves. The speed of a wave in open water is calculated with this rather complicated formula.

v = sqrt( ((g*λ)/(2*π))*tanh(2*π*h/λ) )

Broadly speaking, this expression says that in deep water (such as the open ocean) a wave with wavelength four times that of another will travel twice as fast. So the tsunami, with a wavelength of 100 km, will travel about 20 times faster than a conventional wave of 200m wavelength. Energy can be measured as (Mv2)/2, so the energy in a tsunami is roughly five million times that of the very biggest conventional ocean wave imaginable.

This gives some idea of why a tsunmai is so destructive. Partly it is the energy of the wave, but mostly, it is the length of the wave. Observers' tales of the Indonesian tsunami contrast it with conventional ocean waves which pound in, surge for a few seconds and drain away. While the wave front of the tsunami might destroy most things in its path, the difference is that it just keeps coming, with millions of tonnes of water pushing the surging wave ever further inland. And finally, when all the millions of tonnes of water have smashed every building, drowned every hole and swept all ahead, it all drains back into the sea once more, reversing the trail of destruction and taking property, bodies and belongings back out into the depths.

Sources and further information

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