Talk:Tsunami/Archive 2

Awa

in the article there is this sentence:

• January 26, 1700: the Cascadia Earthquake (estimated 9.0 magnitude) caused massive tsunamis across the Pacific Northwest and in Awa, Japan

To which Awa does it refer: Chiba or Tokishuma? Does anyone know? If not, then no matter. I only ask for disambiguation purposes. Jaberwocky6669 05:07, Jun 25, 2005 (UTC)

There appears to be a bit of an issue raised at Talk:2004 Indian Ocean earthquake#disambiguation request: "Awa" and fact check. After a bit of search it appears that there was no major tsunami in 1703, and I can't find evidence of massive damage in 1700 either. The response to the article here is supported by this data from the NGDC in which the highest death toll between 1700 and 1703 was 5233 on 31 December 1703 for the Tokaido region. Can anyone offer any more evidence for the large tsunami(s) mentioned here and at 2004 Indian Ocean earthquake? - BanyanTree 01:39, 15 October 2005 (UTC)

I was the one who initially added the Awa references to both this article and the 2004 Indian Ocean earthquake one. After seeing all the additional evidence it does seem that the Awa event was misreported in several sources. It may be worth chasing this down a little more before making the WP edits though; for instance if it was indeed the case that this event was reported erroneously in several reputable sources then that itself may be notable enough to comment on in this article. Terry 13:53, 15 October 2005 (UTC)

I've removed the references to Awa both here and at 2004 Indian Ocean earthquake as no additional information has been given refuting the information above that the info is bad. - BanyanTree 00:56, 20 October 2005 (UTC)

Santorini and flood myths

I took this bit about the Santorini eruption/tsunami out of the article: "and is believed by some scientists to have been the basis of Great Flood accounts which were eventually recorded in Jewish, Christian, and Islamic texts." Both the Babylonian and Sumerian flood myths, which are closely related to the Genesis account, predate the Santorini blast by hundreds of years if not more, and as far as I know this is pretty firmly established (e.g. N.K. Sandars, introduction to Penguin edition of Epic of Gilgamesh). If someone has a source about "some scientists" feel free to put it back: I wasn't able to find anything on Google which specifically mentions scientists believing Santorini to be the basis for the flood myths. (Influencing already existing flood myths might be another thing entirely.) Antandrus (talk) 4 July 2005 14:55 (UTC)

New

I wonder what happened to the idea about putting POV first person accounts into the article, it would give it a great feel. Anyone else like that idea?I seek the heart 07:05, 26 September 2005 (UTC)

That would be a blatant violation of WP:NPOV. -- Arwel 16:50, 26 September 2005 (UTC)

Megatsunami

The megatsunami article currently suggests a megatsunami is not a tsunami. However from reading it and from a reading and general understanding ot a tsunami, it appears to me this is qutie incorrect and a megatsunami is simply a media inspired term used to describe particularly large tsunamis, most likely not the result of seismic activity. I have gone into this in more detail in the talk page for megatsunamis. Regardless, the megatsunami article needs to be updated since at the current time, it is either wrong (if I am correct, megatsunamis are tsunamis, unlike what it suggests) or confusing (if megatsunamis are not tsunamis, it does a poor job of explaining the difference) Nil Einne 11:17, 8 January 2006 (UTC)

Magma

The intro to Megatsunami has been changed so it clearly explains that this is just a large tsunami. -- Beland 00:46, 30 December 2006 (UTC)

"Several kilometers deep" / "not a sub-surface event"

I'm confused about the article's assertion that tsunamis are "phenomena which move the entire depth of the ocean (often several kilometres deep) rather than just the surface." This sounds contradictory to the rest of the article's description of tsunamis as energy transmitted as a wave with a short amplitude until reaching shore. The introduction notes: "A tsunami is not a sub-surface event in the deep ocean." So what's up with "move the entire depth of the ocean." Am I missing the meaning of the statement? Thanks! --joeOnSunset 05:36, 17 May 2006 (UTC)

I think what that was trying to say was that when a tsunami originates, the entire depth of the ocean is pushed up. This is true, but it's a misleading way of saying it, so I've cut it out. Henry^Flower 19:07, 4 June 2006 (UTC)

??????

I think you need more information on this site

You can add some...Cameron Nedland 17:57, 2 August 2006 (UTC)

Stop!!

These Tsunamis MUST stop! thousands od homes and peolpe are being killed because no one does anything about the situation. There are three machines in three different parts of the world, not to stop the tsunami's, but to let every one evacuate in time befoure the happenning occours. Help prevent people from dying! x-x-x-x-x-x-x-x-x

Trying to stop a tsunami is like trying to stop the Earth rotating...it can't be done.Cameron Nedland 23:55, 28 October 2006 (UTC)

Plus, what do you expect us to do? Don't forget how much energy these things have - the 2004 earthquake alone had something along the order of 30 MILLION times more energy than the Nagasaki nuke. The tsunami itself - well, that's just too much to be measured I would think. Spark.1.4 01:23, 29 October 2006 (UTC)

ASD

I'm really scared right now!

Stanleyscup07 01:28, 12 December 2006 (UTC)There might be a tsunami in my area! I live in Seattle. The only thing I've heard so far is the whistling noise.

Move to the high ground and you are safe. Kowloonese 03:01, 12 December 2006 (UTC)

2006 - Philippines tsunami

Removed this section because it didn't happen.

A set of needed citations for this page

Please use these citations to support the appropriate material. I see that there is a lack of proper journal citations on this page, and that there is discussion about whether or not different types of tsunamis occur. Since the page is locked, I can't insert these. Thanks to the elves in advance.

Inversion of Deep-Ocean Tsunami Records for 1987-1988 Gulf of Alaska Earthquake Parameters

Asteroid Impact Tsunami: A probabilistic hazard assessment

Landslide Tsunami

Cumbre Vieja Volcano -- Potential Collapse and Tsunami at La Palma, Canary Islands

"Tsunamis" in The Encyclopedia of Physical Science and Technology

Impact Tsunami - Eltanin, Deep-Sea Research

Planetary Cratering: A Probabilistic Approach

Asteroid Impact Tsunami of 16 March, 2880

Ritter Island Volcano- Lateral collapse and tsunami of 1888

The Great Sumatra-Andaman Earthquake of 26 December 2004

Island Arc debris avalanches and tsunami generation

Tsunami Thoughts

The giant Sumatran megathrust ruptures of 1797 and 1833: Paleoseismic evidence from coral microatolls

Also, as a general reference, Steven N. Ward's page is a must have resource. http://es.ucsc.edu/~ward/ Steven is one of the top experts on tsunamis in the world.

69.227.208.201 (talk) 15:36, 2 October 2009 (UTC)EpidemicMan

Winds triggered by tsunamis

We need something on the triggering of winds by tsunamis. viz. http://www.redorbit.com/news/science/1763265/ideal_conditions_made_samoa_tsunami_more_devastating/index.html# "magnitude 8.0 earthquake that triggered strong winds and enormous ocean waves". I'm not a geologist, I'm a microbiologist/epidemiologist, engineer undergrad, but my thought is that if the wave has enough distance, that friction between the air and the wave traveling would get the air moving at the surface of the water. That, and as the wave rises up, it would move a greater volume of air close to the surface ahead of it. Think of the wake of a truck. 69.227.208.201 (talk) 15:16, 2 October 2009 (UTC)EpidemicMan

The dynamic of a tsunami wave train is that the waves are about 1m high in open ocen as they travel fast, but when they hit continental shelves they are slowed down and the water piles up creating the huge wave. Any winds generated would most probably dissipate in the open water due to the low height of the wave trains. When the trains hit shallow water any wind would be negligable because one of the resasons a tsunami is so devistating is the fact that multiple waves crash one after another. This means that any wind wouls be broken up in to packets of air, nolonger recogniseble as wind. The other main problem with the article linked to above is that tsunami waves have nothing to do with generating wind, the cause of the wave be it landlide, volcano, earthquake or another event may cause winds but the tsunami waves themselves no not have anything to do with winds. Im a Geological Hazards Graduate so a geologist that specialises in hazards like tsunami.

Incorrect from the opening line

"A tsunami (pronounced /(t)suːˈnɑːmi/) is a series of waves created when a body of water, such as an ocean, is rapidly displaced ussaully by earthquakes in faults."The tsunami that happened on Mar.11,2011 was very terrible. By Diana S. A.

Actually, a tsunami is not a series of waves but a surge of water. See the article for "storm surge" for some hints as to better describe what is going on.

72.177.34.13 (talk) 03:42, 26 January 2009 (UTC)

Nope. A tsunami is CAUSED by a surge of water. Water being what it is, the surge causes a train of waves to form, (unless the initiating event happens mere miles from your location) and records of tsunamis arriving at shore support this. The first event may be a high or low water, and typically there are a number of waves - the first isn't always the strongest. Geology.com's "What Causes a Tsunami?" site has a graph of a not untypical tsunami down at the bottom. 24.17.178.36 (talk) 03:32, 18 March 2009 (UTC)

Not all Tsunamis are large

The statement 'The effects of a tsunami are always devastating due to the immense volumes of water and energy involved.' is 100% false. Tsunamis can be as small as having a wave height of 5ft, and can have no destructive impact what so ever. This fact can be found in most Oceanography textbooks. --67.234.209.142 (talk) 02:40, 5 May 2008 (UTC)

Corrected. Oda Mari (talk) 15:37, 5 May 2008 (UTC)

Animal Precognition

Suggest that a section about this intriguing phenomenon, observed before the 2004 Indian Ocean event, would add value to the article. Which animals have this sense and know to act on it? By what means do the animals receive prior warning? How long before the event do they receive it? Why don't humans have this ability? Is this phenomenon observed before other major events, like volcanic eruptions, etc? EdX20 00:42, 22 November 2005 (UTC)

"Precognition" is probably misleading in this case, as it implies that it wasn't the result of their normal senses. In the case of elephants, dogs, etc, it is thought that subsonic rumbling of the approaching tsunami provides warning (much like it does for earthquakes). An article I read back in December suggested that unusual behavior by fish, which presumably could detect the pressure changes and other disturbances in the ocean, caused unusual behavior by the shore birds that feed on them and so on across the ecosystem, well before the effects of the approaching tsunami were noticed by humans. All of this, well referenced of course, would be useful in this article. - BanyanTree 16:16, 22 November 2005 (UTC)

I think this section could be removed. The California Department of Conservation, the agency in charge of earthquake readiness, lists this as a myth. The problem is, how can one tell the difference between odd behavior in animals due to an earthquake vs odd behavior due to any other explanation. This may also be a case where it is just a mental trick we play on ourselves, vs hard scientific evidence. In any case, there should be a hard journal article to support this contention.--Dr.Worm 15:43, 11 April 2006 (UTC)

The paragraph beginning "One of the early warnings comes from nearby animals" seems speculative as there were plently of animals killed by the 2004 tsunami. For example, The Washington Post reported, "In the coastal town of Velanganni ... volunteers wearing face masks drove around in trucks Tuesday, picking up cattle carcasses ...". The (Wikipedia) paragraph also says, "The Lisbon quake is the first documented case of such a phenomenon in Europe." If this is actually true, needs a reference. Instead of "Animal Precognition" I'd suggest a section title such as "Do Animals Know Early?" that discusses the evidence. --Dr Smith 22:29, 22 July 2006 (UTC)

---

I believe that animals, specially elephants, can sense the advent of tsunamis. When the 2004 tsunami hit India, there were reports of elephants heading uphill, and away from the coast. We must not forget that elephants are very intelligent animals. They have the ability to sense sound of frequencies we cannot hear. As a result, they can 'hear' the earthquake. And this, together with their high intelligence, must have warned them about the tsunami. We cannot hear this sound, or observe and accurately predict from animal behavior as we are too 'civilized'. We have lost our ancient instincts overtime. But the tribal people of India suffered little, as they could recognize the signs. I can only comment on India, as I do not know much about the rest of the places. --Aftab Lokhandwala (talk) 07:39, 22 November 2009 (UTC)Aftab Lokhandwala

Tsunami wave

I did some English-language redaction on the recently added "Tsunamiwave", but I'm not sure about the raw information itself. First, do we have a source for any of it? Second, I'm uncomfortable about the "N-wave" statement (again, fixed if we have a source). Finally, I'm concerned about my editing of the business about a "solitary wave". The original was:

The Tsunami is also characterised as a Solitary wave (according to shape) which has only crest and no trough.

My version is:

Tsunamis form "solitary waves", or waves with crests but no troughs — more like sand dunes than sine waves.

The problem is that I may have misinterpreted the use of "which" in the original. I thought it meant "a solitary wave which is wave that has only crests…", but it may have meant "a subclass of solitary waves that have only crests…". Solitary wave is unhelpful, as its explanation is purely mathematical, but Soliton (to which I linked the reference, and which specifically mentions water waves in a tank) suggests solitary waves are a more general class, and that a tsunami-style wave is only a single example. I'd appreciate it if someone more domain-knowledgeable could check and possibly correction my changes. Thanks. ~ Jeff Q (talk) 18:34, 19 February 2006 (UTC)

From Samueldevadoss,

It is accepted that, I havent't clearly explained about the 'TSUNAMI WAVE' in relation to solitay wave. Solitary waves are not only mathamatical concept but also a real time event (Solibores or just bores are some examples) and can be generated in experimental wave tanks. The name N-wave is used because the intial form of a Tsunami wave resembles the letter 'N'(exactly at the point of generation of Tsuanmi) and with time and distance it grows to solitary wave. Hope, I will add references soon for justification. Thank you.

A solitary wave or Solitron is generated by water pressure building up in front of the bow of a ship. Some tsunami are not generated by "N" type disturbances but as at Santorini and Krakatau a "U" shaped disturbance due to the collapse of the magma chamber generating a submarine caldera. Incidentally where - as at Sumatra, the ocean floor is pushed up and down simultaneously the resultant disturbance could be more correctly described by a square root symbol \/ ^----. The Geologist (talk) 19:44, 5 March 2008 (UTC)

new interwiki

+ sr:Цунами(What's this? I'm a Newbie) [I don't want to put any of this in the article because I'm still not sure how to identify my edit and post verification.]

RE: "However, an extremely large landslide could generate a megatsunami that might have ocean-wide impacts." The reference here is to shoreline slides.

No amount of land sliding into the sea can create a "megatsunami" or any other kind of tsunami over any appreciable distance. Only a deep-sea slide or tectonic upheaval can generate such a phenomenon. The reason is simple friction. Any wave propagated only on the surface dissipates as it encounters and transfers its energy to all the particles of water in its path, as well as the tremendously heavy air above. This can easily be verified by rolling a large rock -- say a foot across -- into one side of a 100 foot pond. Though at this scale such a rock would represent something about the size of Spain sliding into the Atlantic Ocean, you will see the resulting ripples diminish as they radiate outward, and no change whatsoever in the water at the opposite shore.

However, it must be remembered, at this scale, that even a millimetre rise on the other side would have drastic consequences. Giving the Atlantic's width to be approx 4000km, a 1mm rise in water level on the other side would equate to a tsunami between 100 and 150m high. Obviously such a small rise of 1mm cannot occur on this tiny scale (water tension). --Spark.1.4 11:05, 19 October 2006 (UTC)

You are ignoring the colossal amount of energy that a massive gravitational landlside would contain, which your "large rock" cannot contain unless you lifted it several tens of metres above the ground. The Geologist (talk) 14:41, 14 March 2008 (UTC)

"These events can give rise to much larger local shock waves (solitons), such as the landslide at the head of Lituya Bay which produced a water wave estimated at 50 – 150 m and reached 524 m up local mountains."

The following myth is widely circulated about this event "On July 7, 1958 In a narrow Alaskan bay about 250 miles west of Juneau, the highest tsunami ever recorded loomed to a height of 1,700 feet (520 meters) -- almost twice as tall as the Eiffel Tower."

FACT: A powerful earthquake caused the collapse of a toy house, sending it crashing into one side of the toy truck, thus sending an enormous rush of blocks -- about 1 foot high -- the short distance to the opposite shore, at such high speed that it ran up the opposite slope to a height of 1 inch. There was no such thing as a wall of blocks twice the height of the arm chair by the kitchen , and there has never been anything like this in the last three seconds

Temper, temper! and actually YOU are very wrong. First there are witnesses who did survive the 1958 Lituya Bay "mega-tsunami." Second the scientific and geological evidence confirmed what they told the US Coast Guard service and others. Third the sesimic record confirmed an earthquake. Fourth more recent investigations showed that the block fell almost intact breaking up as it impacted the water at a terminal velocity of about 54 m s² The force it impacted the waters with was colossal - several millions of Newtons per m² and was sufficient to generate an initial wave of approximately 524 m amplitude. All of which is provable and therefore scientific fact. Lest you think I am some pseudo-scientist I assure you and others too, that I am a geologist and have visited Lituya Bay to examine for myself and my research the evidence. The Geologist (talk) 15:05, 14 March 2008 (UTC)

Tsunami researchers have got to curtail perpetuation of the myth that a "big" tsunami means a "tall wave." It does not. The public is constantly being haunted by the image of a prodigious "wall of water" suddenly looming over us, and this is utterly impossible, short of impact by a large celestial body. There is no evidence whatsoever that any tsunami traveling an appreciable distance across the ocean can make landfall at some monstrous height above sea level. When such a wave approaches a shore, receding water causes it to rear up temporarily, but then it curls, crashes, and races onto the land in a sloped configuration -- just as a normal wave does -- but it does so at high speed. It's the velocity, not the height of the wave, that causes so much destruction. A massive volume of water traveling at high speed with great inertia, even a few yards above sea level, can exert tremendous force over a great distance inland. Constant reports of towering waves are based upon the height to which such surges have run up inland slopes, NOT the actual height of the waves.

What causes the wave to "rear up" isn't the drawback, but the physics of wave formation. As a wave comes ashore, the base slows but the upper part continues to travel forward at the same speed - just like a person in a car which is braking hard is forced forwards because they are still travelling at the original speed of the car. In addition to this the water rises BECAUSE the shore area slopes upwards forcing the water upwards. This rearing up causes drawback not the other way round. Photographs taken of the Indian Ocean tsuanmi clearly show the approaching wave rising BEFORE the drawback commenced. I personally have a set which have been extensively studied and analysed by colleagues around the world. Drawback is an artefact of the rearing up which is an artefact of the tsunami. Simply put you have a tsunami wave which extends from the surface to the sea bed - which is why tsunami waves obey the same rules as shallow waves, this is pushed upwards as it approaches land, causing he wave to rear up and thus generate drawback which often occurs with a tremendous sucking sound. The incoming wave surges ashore and can inundate upto several kilometres inland. The Geologist (talk) 14:56, 14 March 2008 (UTC)

Corroboration: Dear Dr. Shiarella, Thank you for your correct comment. We will see if we can put a description of the actual wave on our web site, and I will make sure this is clearly noted in training presentations. Regards, Laura Kong, Director, International Tsunami Information Center Drshi 23:02, 14 May 2006 (UTC)

This may well be true (I've no idea), but there are very respectable-sounding people who do argue that landslides can cause tsunamis: [1] Given the inclusion of could and might in the original statement, I think it should stand. Henry^Flower 11:29, 16 May 2006 (UTC)

Sure, and there is also a one-hour documentary touting this pseudo-disaster, in which researchers are shown estimating the size of a surface tsunami over 2,000 miles from its genesis by sliding rocks into a water tank only a few yards long. Debunking sites include http://www.lapalma-tsunami.com/ and http://www.drgeorgepc.com/TsunamiMegaEvaluation.html Drshi 22:01, 17 May 2006 (UTC)

I don't pretend to understand the physics/geology/whatever of the matter; all I (or anyone at Wikipedia) can do is to look at what reputable sources say. Some say that a landslide could cause a tsunami, while some don't. Unless one side concedes, it's not for us to take sides. Henry^Flower 22:07, 17 May 2006 (UTC)

An underwater landslide has been blamed for the July 17 1998 Papua New Guinea tsunami (which killed approx 2200. I'm concerned that wikipedia doesn't appear to have a page on it) by some scientists, yes - [1 http://www.sciencenews.org/pages/sn_arc99/8_14_99/fob2.htm] [2 http://earthguide.ucsd.edu/seafloorscience/slopes/slopes_story.html] --Spark.1.4 11:05, 19 October 2006 (UTC)

Investigations showed the same scaring on the surface of sediments off the coast of Papua New Guinea (Tappin, D; 2001. Local tsunamis. Geoscientist. 11-8, 4-7),as are seen at the site of the Grand Banks and Storegga slumps. The Geologist (talk) 14:56, 14 March 2008 (UTC)

Well, though as of now this site does not represent an "us" to me, it seems that when two legitimate sides to an issue exist, both should be equally represented. To my mind, it does not take a physicist or geologist to see the patent absurdity of a shallow landslide of any size propagating a tsunami over the surface of a sea for thousands of miles. A tsunami is NEVER a surface phenomenon, as verified above by Laura Kong. Those who have lept to such conclusions have done so on the basis of geological evidence found in remote areas that suggests a possible link to other areas far afield at which such slides have ocurred. Not exactly incontrovertable. Drshi 14:36, 18 May 2006 (UTC)

I certainly agree that both sides should be equally represented. Bill McGuire, a professor at a very respectable university, [2] does not think the idea is patently absurd. We should say that some people think it could happen, and some people think it couldn't. Henry^Flower 14:51, 18 May 2006 (UTC)

Of course, we don't know whether or not the positions of McGuire and other pro-tsunami researchers have been modified since the subsequent proffering of opinions and evidence to the contrary, do we? Drshi 16:51, 21 May 2006 (UTC)

I certainly don't. But the idea can hardly be as absurd as you make out if they believed (and, AFAIK, believe) it. Henry^Flower 18:26, 21 May 2006 (UTC)

My previous comment states that the supposition is absurd "to my mind"; it does not proclaim absolute absurdity. However, I am certainly not without credentialed support in my belief, and history is replete with virtually universal scientific opinions that have since proved dead wrong, even absurd. I did my own research in my backyard pond, as described in my initial entry, and I feel that any person with a reasonable intellect and imagination should be able to conclude that, in the case of a non-stagnant, 100' pond of any depth and shoreline slope, it would take a landsliding mass about the relative size of Europe to cause any effect at all on the opposite shore. Sometimes the most simple observations are far more telling than complex scientific extrapolations, as famously illustrated on TV by Caltech physics professor Richard Feynman, when he placed a small O-ring into ice-cold water and showed its loss of pliability before an investigative committee on the Challenger space-shuttle disaster. With all due respect, it's beginning to sound to me as if you hold some kind of stock in the tsunami theory, otherwise your investment here might be more productive were it aimed at assisting this newcomer in inserting the equally valid opposing view into the attendant article. ;-)

PS It also seems to me that you are too eagerly taking the findings of establishment researchers at face value, as though they are operating in some sort of academic ivory tower. The way this whole issue got started was that some researchers applied for grants on the basis of a possible tsunami devastating the coasts of Great Britain and America. Of course such a hypothesis would prove attractive to funding sources; but what would be the odds of such a grant being extended were a researcher to report a first year finding that there was no solid support for such a hypothesis? Unfortunately, scientific theories are seldom without bias of one sort of another, while those who debunk such theories are usually independent mavericks with no special ax to grind other than maintaining the purity of scientific method. Drshi 11:53, 24 May 2006 (UTC)

I don't know where some of you get or got your information as written above. Lituya Bay DID cause a wave with an amplitude of 524 m - that is documented. It was not a "splash." Volcanic edifice failure "... Will cause the western flank of the Cumbre Vieja on La Palma to fail and generate a so called "mega-tsunami ..." Will it? There is a lot of evidence to support the claim that the flank will not fail en-masse, but rather in a series of sector collapses. Consider this the Cumbre Vieja is about 25 km long and in 1949 an eruption occurred which was accompanied with an earthquake. This earthquake is considered by some to indicate that the volcano is about to collapse - so run for the hills! Well the section that opened in 1949 is about 2.5 km long or about 10% of the total length of the Cumbre Vieja. The sector moved about 2 m vertically and about 1 m horizontally. Hardly a precursor to imminent failure. However, the hypothesis cannot be proved UNTIL it undergoes sufficient eruptions to cause failure and it may then generate a massive tsunami - the so called "mega-tsunami!" As a volcanologist and a geologist who lives and works in the Canary Islands I am involved in ongoing research into the potential falure.

Any tsunami requires the WHOLE water column to be disturbed - not just the surface and massive gravitational landslides may have the ability. Submarine seismic activity of high enough magnitude will - Chile 1960, Alaska 1964, Sumatra 2004. Bolides impacting the ocean will also if of sufficient mass generate a tsunami. Landslides and submarine slumps may cause localised tsunami - Grand Banks 1929, Papua New Guinea 1998. Massive volcanic explosions will (if they affect the water column), generate a tsunami - Santorini about 3615 BP, Krakatau 1883. As the Sumatra earthquake showed sesmically generated tsunami have the ability to travel transoceanic distances.

Whether a volcanic edifice failing would generate a transoceanic tsunami or so called "mega-tsunami" is the subject of ongoing research. The Geologist (talk) 19:36, 5 March 2008 (UTC)

Here is something hot out of the laboratory! A recent experiment involving a tank 100 m long 15 m deep and 5 m wide was undertaken. It also used a slope inclined at 15 degrees (and this was varied between 10 and 25 degrees) and 25 m³ of sand and gravel. When the sand and gravel slid into the water it generated a "tsunami" which came surged over the distant end. The height of the wave was almost 24 m. SO - perhaps there may be some basis of Day et al; 1999, and Ward and Day; 2001, work. Research continues and watch this space! The Geologist (talk) 17:39, 18 March 2008 (UTC)

Video

Is this appropriate: Rare footage of the 2004 Tsunami its a video entitled 'funny tsunami' i have been reverting it, but i'm just checking that i'm doing the right thing by stopping it?

I don't think there is anything funny about that or any other tsunami. Only a sick mind could think it funny to loose your friends or family. The Geologist (talk) 19:13, 5 March 2008 (UTC)

Magnitude

Does anyone have any information in which a minimum magnitude is associated with a tsunami. This could prove useful knowledge for those who live in tsunami prone areas. 21:29 28 August 2006 (HST)

I don't believe that there is a 'minimum magnitude' as such, as a fairly moderate earthquake (say a 5 or 6) could cause an underwater landslide which could be just as devestating as a 9 or 10.--Spark.1.4 10:51, 19 October 2006 (UTC)

Almost any seismic disturbance can initiate a tsunami. However a low Magnitude earthquake at depth would not. I believe that in Japan any sesimic activity of Magnitude 4 or greater can initiate a local tsunami. For this reason people in coastal areas of Japan are very aware of the risks and have well rehearsed procedures and routes to evacuate low lying coastal areas. Perhaps someone from the Japanese scientific community might like to comment. The Geologist (talk) 19:12, 5 March 2008 (UTC)

question

can anyone explain how the tsunami wave appears to sometime cause water to retreat from the shore at first?Edxguy 14:24, 3 December 2006 (UTC)

research waves in general, have you ever been to the beach? before every wave, the water goes out. if it didn't ever go out all the water would be on the land and not in the ocean.

The above reply is not correct. A tsunami has two phases - as does any wave. A positive peak and a negative peak in respect to the original sea level. Which are due to the manner in which sea floor disturbances disrupt the water column. The section that pushes upwards - positive direction pushes the water column upwards, whilst the part that in effect moves downwards - negative draws the water column downwards. The disturbance then radiates outwards - the positive section will literally arrive as an overflowing - Banda Aceh and similar areas on 24th December 2004 were suddenly inundated without any warning. This was due to the positive peak arriving without any indication. Other areas saw the sea recede - the drawback due to the arrival of the negative peak.

It is difficult to decide which is the more dangerous in respect of the fact that people invariably investigate why the sea suddenly withdraws ( many survivors of tsunamis mention a "sucking sound,") because when the sea "returns" it rushes in faster than you can run. Yet if you keep your wits about you that drawback will give you valuable time to run to high ground or get above the third or fourth floors of high rise buildings.

The sudden inundation is dangerous for many obvious reasons. There is no warning you are suddenly engulfed in several tonnes of water moving at speeds close to 1000 km hour and to give you some idea of the force involved the velocity of the wave (m per second squared x the mass will give the force). The wave will arrive with a velocity of about 280 m per second. Sea water has a density of 1.1 x 10³ kg m³, hence each cubic metre of sea water hit had an approximate force of

280² x 1100 = 8.61 x 10⁷ N m² or the equivalent force of 86 million tonnes per square metre. Please note that this is not the actual force that the wave exerted as it came ashore. This is because as it came ashore its velocity reduced, but the energy present didn't. In arriving at an actual value several factors have to be taken into consideration not least the distance travelled - the energy dissipated according to the inverse square root theorem rule. The Geologist (talk) 19:11, 5 March 2008 (UTC)

Stats

The article Great Chilean Earthquake has a different fatality figure than this article. -- Beland 02:09, 31 December 2006 (UTC)

The earthquake article mentions earthquake fatalities; the tsunami article talks about tsunami fatalities - I don't think there's any contradiction - apples and oranges. SandyGeorgia (Talk) 05:44, 9 January 2007 (UTC)

Anyway, since it's not clear, I added the referenced number from the CRED database. SandyGeorgia (Talk) 05:47, 9 January 2007 (UTC)

You might also like to read an account by Houron Tazieff called "When the Earth Trembles," which contains a graphic account of the earthquakes and tsunami. The Geologist (talk) 19:10, 5 March 2008 (UTC)

1755 - Lisbon, Portugal

This section is confusing (to me at least):

"Tens of thousands of Portuguese [...] were killed by a tsunami which followed a half hour later."

"The earthquake, tsunami, and many forest fires killed more than 1,000 of Lisbon's pre-quake population of 275,000."

Either that's mistyping, or it's saying that tens of thousands of Portuguese were killed, but only 1,000 of them were actually from Lisbon.

217.194.34.103 10:17, 6 March 2007 (UTC)

The Portuguese Wikipedia says in the article about the 1755_Lisbon_Earthquake at http://pt.wikipedia.org/wiki/Terramoto_de_Lisboa (my translation): "From a population of 275 thousands in Lisbon, it's believed that 90 thousands died." In a remark about this claim, the article also says (my translation) "There are sources citing 30,000 mortal victims." Jayme 18:42, 29 May 2007 (UTC)

Japanese legend

I removed the statement It, in Japanese legend, is thought to be caused by a giant fish-god swimming around under the ocean, causing a tsunami because the legend is (at least in every reference I dug up) that earthquakes, and not tsunami, are caused the giant catfish's writhing. I know it sounds kind of nitpick-y, but since not all tsunami are caused by earthquakes, the line isn't completely accurate. Mary quite contrary 05:07, 16 March 2007 (UTC)

Really?

"ca. 1600 B.C.: The Israelite crossing of the Red Sea has been linked by some researchers to a tsunami following the volcanic explosion of the Greek island of Santorini."
Which serious researcher would come to the idea that a volcanic eruption in the Mediterranean would spark a tsunami in the Red Sea? Is this an attempt by some creationist to infiltrate the "science" of the christian religious texts into science again?
That should be deleted as it is complete nonsense.
—The preceding unsigned comment was added by 85.3.187.12 (talk) 15:57, 27 March 2007 (UTC).

No, this is an attempt by some non-religious scientist to explain what religious people regard as supernatural. It was referred to by Dr Iain Stewart on the BBC programme "10 things you didn't know about tsunami" which aired recently. Moonraker12 (talk) 12:43, 19 January 2008 (UTC)

this is a really good site and helps you alot with all of the work you might need fopr school. —The preceding unsigned comment was added by 24.239.67.53 (talk) 01.16, 29 March 2007 (UTC).

There is an agreement that the Israelites did not cross the "Red Sea," but the "Reed Sea" which is documented as existing in the southeastern corner of the Mediterranean Sea and was still in existence at the time the Suez Canal was constructed. There is strong probability therefore, that "Red" is a misinterpretation of "REED" and I am certainly not a "Creationist" I do happen to be a geologist and a volcanologist and deal with provable facts to what some consider to be stories. I believe that the bible contains a history of the Jewish people, and as such it has recorded many natural events which the writers were only able to explain as "Acts of God." There is a time difference between the radiocarbon dating of the Santorini explosion and the archaeological date of the Exodus of 300 years, but you must bear in mind that there is also uncertainity about the date of the Exodus plus it is highly unlikely that the description wasn't written immediately and the writer may have confused the pharoah.

If the Reed Sea was the place where the Israelites crossed the sea "dry shod," then their crossing may have coincided with a drawback of the Santorini tsunami. The armies of pharoah were drowned in the returning surges. It is plausible but is not provable at the present time, though a search is under way for the tsunamite - deposits made by a tsunami. The Geologist (talk) 18:26, 5 March 2008 (UTC)The Geologist

Bounce-back tsunami

"These tsunami were so large that they caused landslides on the opposite coast triggering another massive tsunami, or "bounce back" tsunami. An example today would be a landslide equivalent to everything west of Portland, Oregon falling into the Pacific Ocean, resulting in a tsunami that would then hit the Chinese coast with enough force to erode the coast, triggering a landslide large enough to send a tsunami that would in turn inundate the U.S. West Coast and would wipe out Portland."

I'm not sure how even a very large tsunami alone could cause a landslide large enough to generate another ocean-wide tsunami. This sounds implausible, and I've never heard of anything like it before. Added to which, the scenario of everything west of Portland "falling" into the ocean is ridiculous and not sensible for inclusion in a serious encyclopedia. But hey, if someone has a reference, let's have it in there. —The preceding unsigned comment was added by 203.173.58.133 (talk) 16:47, 1 April 2007 (UTC).

On further consideration, this may be a confusion with tsunamis being reflected, which may well (does?) happen so far as I know, though obviously with a large loss of energy. References would be handy, and until then I suggest leaving more extreme paragraphs like this out. And sticking to realistic geological examples.

Whilst it is possible that a tsunami could trigger landlsides on distant shores, it is extremely unlikely that the landslide could then trigger a further tsunami. This is because the incoming energy present in the waves would be inundating the shore, massive damage would result and the energy that a landslide would impart into the incoming tsunami would be absorbed and dissipated locally. Reflection of the waves may give the impression that a fresh tsunami was being generated. The Geologist (talk) 19:08, 5 March 2008 (UTC)

2004 Indian Ocean Tsunami

I found this line in the article surprising, and hard to believe: "The American recording stations in Hawaii detected the tsunami within a few minutes of it starting, but as it posed no danger in their locality they did not publish a warning." According to: http://www.noaanews.noaa.gov/stories2004/s2358.htm they detected the earthquake- but not the tsunami, because they don't have any buoys in the Indian Ocean, and they did send out warnings. I think this line should be deleted or cited.

Athenastreet 18:47, 4 April 2007 (UTC)

no name for sue nommy

The TSW sation in Hawaii and other seismic observatories around the world recorded the SEISMIC WAVES from the earthquake within minutes of the earthquake occurring. They DID NOT record the tsunami It was several hours later it was recorded and then only as a small disturbance on tide gauges outside the Indian Ocean. The Geologist (talk) 19:03, 5 March 2008 (UTC)

The naming of this Tsunami as Indian Ocean Tsunami while is appropriate is confusong for in media the event is known more as Aceh Tsunami. My son who is looking for the event can't find or recognized that the Indian Ocean Tsunami is the Aceh Tsunami.

It is a big surprise (and very difficult for people to associate with the tsunami) that Banda Aceh (the provincial city name), Aceh (the province) and Indonesia (the country) where the tsunami centered is not mention here. Nor other countries that were effected in the lesser scale such as Thailand, Malaysia, Bangladesh, etc). Also not being is mentioned the magnitude (the wide area effected, the height of the wave) of the event.

Also I belief more than 100,000 people died in the event. In Aceh itself more than 70,000 people perished. A few inhabited island in ythe coast of Sumatra were also whipped out. —Preceding unsigned comment added by Vivi santosa (talk • contribs) 01:21, 27 October 2009 (UTC)

This section claims over 300,000 people were killed in the 2004 tsunami (with a "citation needed" caveat), but several other sources talk about around 250,000 casualties. For example: CNN: http://edition.cnn.com/2009/WORLD/asiapcf/12/26/tsunami.anniversary/index.html "about 250,000 people in 14 countries" BBC: http://news.bbc.co.uk/2/hi/asia-pacific/6209413.stm "claiming almost 250,000 lives" Wikipedia: http://en.wikipedia.org/wiki/2004_Indian_Ocean_earthquake "a total of 229,866 people lost" (again, citation needed) 78.21.63.70 (talk) 19:47, 28 December 2009 (UTC)

Plural of tsunami

According to Merrian-Webster, the plural of tsunami can be either tsunami or tsunamis. Personally, I prefer the former simply because I’m accustomed to it, but most NES (native English speakers) might prefer the latter, which could lead to edit wars over this. Any suggestions for averting such silliness, such as perhaps a notice or footnote stating that either is correct, but we’ve (“Who’s we?” is the obvious retort, of course) settled on one or the other? Jim_Lockhart 02:36, 13 April 2007 (UTC)

I've thought about this as well. My instinctual reaction is, we don't automatically add "s" to pluralize every English word, so why should we do it - inappropriately - to a word from another language? My more logical reaction is to look at other Japanese words ending in "i" that have made their way to us and how WP treated them. For instance, according to the dictionary, it's an acceptable to pluralize origami with an "s", but our WP article doesn't use this version. A better argument is "sushi", which nobody in their right mind would call "sushis".

Then again, having lived in Japan, I have a little personal bias and definitely get itchy when I hear or read "tsunamis". But I'm not sure what the consensus is/was/would be here. --Mary quite contrary ^(hai?) 03:33, 13 April 2007 (UTC)

As a geologist and a volcanologist the scientific community uses the singular - "Tsunami", whilst the media sometimes uses the plural - tsunamis. The Geologist (talk) 18:34, 5 March 2008 (UTC)

Inappropriate remark?

Since not all tsunami occur in harbors, however, that term is equally misleading, although it does have the benefit of being misleading in a different language.

I fail to see where's the benefit in that; looks completely non serious to me, any reason to leave it in? Perseguidor 13:59, 15 April 2007 (UTC)

To clarify: actually I do see the very practical benefit of that (it isn't as misleading an error to the general public), but the remark strikes me as badly worded. I wanted to know whether I'm just being culturally oversensitive because of the fact that english is not my first language. Perseguidor 14:04, 15 April 2007 (UTC)

The comment could be worded better. Also, the "Signs of an approaching tsunami" section needs work. Could "disgustingly fat wave" be vandalism? Has a tsunami ever washed "over an entire country"? The last sentence in the section, "Although in the 2004 tsunami in the Indian Ocean the sea receding was not reported on the African coast or any other western coasts it hit, when the tsunami approached from the east" doesn't seem to fit in that section at all, and is not a complete sentence, in addition to being very poorly worded.

Additionally, the section on the 2007 Solomon Islands tsunami is written using some present tenses (it is not timeless, as all wikipedia articles should be) and also needs to be updated with conclusive data. --Cromwellt|talk|contribs 19:46, 30 April 2007 (UTC)

Well the scientific community worldwide know what a tsunami is and so do most people who live in vulnerable areas. The Geologist (talk) 19:05, 5 March 2008 (UTC)

Gas bubble image

I've commented out the "Gas bubble" image (Image:Tsunami5.JPG) pending a reference for this. Maybe gas bubbles cause tsunami, but I'm a bit skeptical. Ref. please. Vsmith 01:38, 24 May 2007 (UTC)

Scepticism in this case is justified. A gas bubble would cause a sudden localised disturbance which might resemble a tsunami in the immediate vicinity, but it would not be large enough or powerful to generate a tsunami. The Geologist (talk) 19:07, 5 March 2008 (UTC)

Splitting article?

The section of notable tsunamis is large, perhaps we could create List of notable tsunamis and simply link to it here? - 2-16 17:22, 6 June 2007 (UTC)

A Tsunami does not have to be 'on a massive scale'

A tsunami (soo-nah-mee; IPA: /tsʊˈnɑːmi/) is a series of waves created when a body of water, such as an ocean, is rapidly displaced on a massive scale

This should read:

A tsunami (soo-nah-mee; IPA: /tsʊˈnɑːmi/) is a series of waves created when a body of water, such as an ocean, is rapidly displaced

Or something simmilar, could someone please confirm

69.156.99.171 17:46, 30 June 2007 (UTC)

A tsunami is generated when a large body of water - usually oceans but sometimes in lakes and inlets or fjords, is suddenly displaced by vertical displacement of the ocean or lake floor. Large bodies - asteroids, massive landslides etc., falling into the ocean or lake can also have the same effect The Geologist (talk) 18:57, 5 March 2008 (UTC)

Split

What about to move a Historic tsunami section into a new article? It is quite long now and it looks ugly here. Miraceti 14:12, 25 July 2007 (UTC)

Removed content

I have removed the following (unreferenced etc.) section from the article:

---

Samui Kaze Desu,( Cold Wind Query) a Japanese expression, meaning ' Isn't that The Cold Wind?' - a small cold wind from the sea that often preceeds the tsunami.

It seems that when a vast volume of sea water is thrown into the air, a similar volume of air is displaced, and consequently a wave of air flows outward from the eruption.

This wave of air travels faster than the wave of water, and is cold by the time it comes ashore because it travels across the surface of the water. It may arrive seconds or minutes before the tsunami,depending how far out the eruption is, or maybe not at all ( perhaps if the first onslaught of the tsunami is a recession of water ?).

Experienced Japanese leave the shore immediately.

---

Mike Rosoft 14:12, 30 September 2007 (UTC)

"Fillius Sum Sunamus"

Arrant nonsense in the opening graf. Argh. 128.2.247.61 07:01, 12 November 2007 (UTC)...

Pronunciation

Both the Oxford English Dictionary and American Heritage Dictionary only list the "tsunami" pronunciation. They do not even have a "sunami" pronunciation therefore the "tsunami" pronunciation is first. Azalea pomp (talk) 17:00, 26 December 2007 (UTC)

I removed the 'sunami' pronunciation. It's incorrect. Oda Mari (talk) 18:24, 26 December 2007 (UTC)

Most English text books - as used in the English speaking world clarify the pronunciation as "Sue - nar - me" which may seem strange but it emphasises the syllabuls and tries to ensure correct pronunciation. The only time I have seen tsunami spelt incorrectly as "sunami" was on here. It isn't spelt that way - it is spelt "TSUNAMI." The Geologist (talk) 18:52, 5 March 2008 (UTC)

I suggest that the article should state that the pronounciation /(t)suːˈnɑːmi/ is how it's pronounced in English and not in Japanese, as one may think, as it's originally a Japanese word. Like this: A tsunami (津波?) (pronounced in English as: /(t)suːˈnɑːmi/) CayenneGaramonde (talk) 17:25, 17 September 2009 (UTC)

Tidal Wave Vs. Tsunami

I would like someone to explain to me why "Tsunami" and not "Tidal Wave". I know the second is caused by the tides of the moon, but considering Tsunami is mentioned as meaning "Harbor Wave", I cannot see why use it except political correctness. If I'm wrong, okay. Thank you.--65.24.61.74 (talk) 23:58, 15 February 2008 (UTC) STRodgers

Sorry, it is not "Political Correctness" that we use the term "Tsunami", but it like many other terms used in science has been taken in general usage. For example what about Strombolian, Vulcanian, Plinian to describe explosive eruptions of increasing intensity, or hurricane - named after the Carib god "Hurakan or Huriken." What about "Lahars" to describe volcanic mudflows - it is an Indonesian word, or Nuee Ardente to mean "Glowing clouds" it's French. The list is endless. The Geologist (talk) 18:41, 5 March 2008 (UTC)

OK - this 'The use of the term "tidal wave" to describe a tsunami is wrong because IF NO wind were to act upon the sea, then as the tide flooded (rose) or ebbs (drains) solely under the influence of the Moon and Sun, the water would rise and fall without any wave. Non-tsunami waves form by the action of wind on the upper surface of the sea.'

Is ... useless in the context of this article, not to mention that the first sentence is poorly constructed and doesn't make any sense. It should just be deleted - It is sufficient to say that a tsunami may be called a tidal wave by some but that it is discouraged because a tsunami is completely unrelated to tides. (which is already said by the sentence preceding and following the aforementioned flotsam) 67.167.185.45 (talk) 21:38, 12 April 2008 (UTC)

Scientists avoided the term "tidal wave" not only because its origin is wrong. Important difference between terms "tsunami" and "tidal wave" is that "tidal wave" has another confusing meaning: there is a wave (somewhat similar in its size) which is caused by tidal forces. Such confusions are harmful for many people who work against tsunami disasters. For term "tsunami" there is no such confusing thing, both in English and Japanese. It should also be noted that the origin of "tsunami"'s meaning — "tsu" stands for "a harbor" — is, unlike "tidal", only an ancient meaning. The term "tsu" is no more an independent word in modern Japanese and remains only in already-combined words (such as tsunami) or names of locations (such as Tsu and Akitsu). Most of recent Japanese people might not even notice that "tsunami" originates from a harbor wave. --Y.oiwa (talk) 18:28, 8 June 2009 (UTC)

Where did my picture go? Everyone, please warn people if you are going to replace their pictures...

Hi everyone:

My photo

File:IMG 5028.jpg

Allison's photo

I looked at this article for the first time in about a year today and noticed that my photo was gone. I traced the history and figured out what happened. At this edit on 16 March 2007, User:Allison Stillwell replaced the first photo on the right (mine) with the second photo (hers) without any warning.

I don't think this was a good idea. Although both photos share a common deficiency (sun is not to photographer's back), here is why my photo is superior:

• Mine is straight on at the subject; hers is from a very sharp oblique angle and below.
• Mine is illuminated by a flash for superior contrast; hers appears to not have any flash (or was not taken with a strong enough flash).
• Mine is cropped so as to make the sign fill the frame; in hers, there are significant background objects that do not contribute any additional relevant information.

Okay, do we have a consensus to go back to my image? If no one responds, I'm changing the article in a week. --Coolcaesar (talk) 08:39, 24 February 2008 (UTC)

I prefer yours to hers. Because the warning is legible. Oda Mari (talk) 09:41, 24 February 2008 (UTC)

I prefer hers. better quality photograph overall, is not "false coloured" (flash in daylight shooting? what?), hers looks like a photograph you might see in a professional article, yours looks kinda not so good and lopsided and off centre and has things reflected in the sign and is just pretty terrible. also i prefer hers because she's not in here after a YEAR going "wah, MY PHOTOGRAPH." you're not supposed to have "pet articles." not yours. 82.8.49.243 (talk) 03:27, 26 February 2008 (UTC)

oh, i see by your talk page this isn't the first time you've thrown your toys out of the pram over someone daring to touch one of your photos. 82.8.49.243 (talk) 03:44, 26 February 2008 (UTC)

I'm sorry you feel this way, but the reason I replaced the photo is that yours has odd reflections and has a bit of a fisheye to it. I think that mine is a little more professional in terms of composition and colouring, and in the year since it was posted, no one has complained about it. I really, really think you're overreacting here. --Allie (talk) 03:41, 26 February 2008 (UTC)

Well, I am aware of the problem with the flash reflection and the fisheye issue (actually barrel distortion, a common problem with most Olympus "prosumer" cameras). This was back while I was still developing my photography skills.

But the main issue is that the entire point of the photo is to show the content of the sign -- namely, that it's a "tsunami warning sign." This is not like photographing, say, a natural landmark or a building, where there are a huge number of possible angles in three-dimensional space, many of which are attractive. In this case, either the sign is readable or it is not. I'm not sure if you realize that most Wikipedia readers don't have the time, curiosity, or bandwidth to follow links from thumbnails to see the images in full, so it's important that the thumbnail versions of images are easily understandable when seen in articles. You make a rather conclusory statement that your image is more "professional" in terms of composition and coloring without providing any explanation; I simply can't agree. This is not a fancy art image; this is about displaying the content of a sign. Besides the issues I already raised, yours is much harder to read in that it is sharply offset and rotated on all three spatial axes (X, Y, and Z) relative to the subject. --Coolcaesar (talk) 07:55, 27 February 2008 (UTC)

If you want to replace a picture, then do it. Believe it or not, you don't actually have to alert every single person who ever edited that you're replacing their content -- if we had to do that, nothing would ever end up being updated on Wikipedia. I stand by my statement that you're absolutely overreacting here -- it's a picture for God's sake, a single picture. If you react like this, so something that is so insignificant, I find myself terrified that you're ever representing someone in the courtroom. I think you're also being rather haughty about this and that maybe you should consider how you talk to people, but I see from reading your talk page that this has been a constant problem for you. I hope that for both your health and your career you learn to calm down. There are some times when things just aren't worth getting upset over, and one of those things is edits on Wikipedia. It's a website, not some deeply personal thing that people are going around and changing to insult you.

And if you realise that there are problems with composition, why don't you go take another picture of the sign? I'm only in California a few times a year, but you live where there are tsunami warning signs everywhere. It seems to me that if you've been improving your photography skills, you can take a rather nice picture of the sign now, one without the flash reflection and barrel distortion. You seem to like taking photos of anything, so why not just skip over to the coast and take another picture? I'm typically a portrait photographer and inanimate objects tend to bore me to no end, but you appear to love such things, so embrace them... with a better picture. --Allie (talk) 16:41, 27 February 2008 (UTC)

it's not to show the content of the sign, it's to show the general appearance and whereabouts of the sign. the article is for the content. you are being a prissy butt. 82.8.49.243 (talk) 04:30, 28 February 2008 (UTC)

The first photograph may have failings but legibility of the information is not one of them. The second one shows that the sign is positioned on a post - but here is the crucial thing - it is illegible! I also consider it bad manners to remove someones postings just because you don't like it - unless it is libellous, wrong or illegal. A better solution would have been to leave the original photograph and add the second to show the position. Flash is regularly used in daylight - go and read a book on photography. Also many automatic cameras do not offer the user the option of flash on or off. Before criticising make sure of your facts. Incidentally I am a professional geologist and volcanologist and photography plays a BIG part in my observations and I don't always get the shot I really would like. The Geologist (talk) 18:48, 5 March 2008 (UTC)

How about this picture? Oda Mari (talk) 14:55, 11 March 2008 (UTC)

Oh, I like that one a lot! Good shot! --Allie (talk) 02:52, 16 March 2008 (UTC)

Hi Oda Mari, Pics OK too. Might have been enlarged or cropped but it is legible and that is what matters. The Geologist (talk) 15:19, 14 March 2008 (UTC)

Just got caught up on what's going on. I have been too busy with working at the firm, attending social functions, finishing my tax return and taking online traffic school to work on Wikipedia. I agree that the photo brought in by Oda Mari is a well-composed and acceptable compromise. Oda, feel free to put that photo into the article any time. --Coolcaesar (talk) 06:24, 16 March 2008 (UTC)

For whatever it's worth, this is the same sign design, clearly visible, from Laguna Beach, CA. WarBaCoN (talk) 08:02, 16 March 2008 (UTC)

Why not use all the images? As a gallery, it will need monitoring to ensure that rubbish images are not used. However, if the image is clear and legible, then fine, but lets use a bit of common sense. We don't need a gallery of signs showing "This is the sign on XYZ street" The Geologist (talk) 15:04, 16 March 2008 (UTC)

No need for sarcasm. I noticed a lot of people were going on about various issues with all of these pictures, and this one cleared up a lot of the complaints. If an ideal image was found, the rest could be eliminated as the issue would then be resolved. Sounds like common sense to me. WarBaCoN (talk) 17:39, 16 March 2008 (UTC)

Well I'm NOT being sarcastic as you seem to imply. As a scientist - I am a professional geologist, it is my duty and any one else presenting information to ensure it is correct, legible and easily identifiable. If you go in to the world you will see that different countries present tsunami warning signs in different ways - and strangely not all the signs in one country are the same - unless they have changed them in the last 48 hours! The country? Why its that big blob that sits beneath Canada and above Mexico - alias the USA! The Geologist (talk) 18:33, 17 March 2008 (UTC) b

FYI, "Sarcasm, A form of irony in which apparent praise conceals another, scornful meaning". Anyway, I am not even sure what you are trying to say. I think we all know that different countries use different signs. In fact, where I am from we have NO tsunami warning signs at all, as many others around the world may not while skimming this article. I offered what appeared to be the best photo of the sign in question, that everybody was discussing, in a clear, straight on, and legible picture. I have zero interest in distracting you from your discerning scientific work (in more important areas, I am sure). WarBaCoN (talk) 21:50, 18 March 2008 (UTC)

Oh dear WarBaCon you seem to get annoyed at anything which is not to your liking or suits your opinion. I would like to know where you are from as my own travels around the Pacific Rim I know of only two locations where there is no Tsunami waring signs and both of them sign themselves as US or USA! Comprende. Yes my work is scientific and discerning and truthful. If you can't take criticism then go and play somewhere else not where the adulst are trying to educate ignorant pseudo-scientists who take umbrage when they are proved wrong! The Geologist (talk) 17:21, 30 March 2008 (UTC)

The idea that someone would replace a photograph chosen for content with another because it "looks more professional" is beneath contempt. It shows a pretty thorough lack of understanding of what an encyclopedia IS or is FOR. Professional taste is as faddish and irrelevant as any other taste - just look back through a few decades of print magazines. And a GALLERY of tsunami warning signs sounds like taking a bad idea to the mass duplicators, for the sake of...what? 24.17.178.36 (talk) —Preceding undated comment added 03:51, 18 March 2009 (UTC).

edits for Warnings and prevention

The previous writing of the section not only has errors, but also doesn't use the usual variable letters in some cases. I suggest the following changes be made to bring them in line with normal variable usage.

Here's the before:

F = Gdh

where F = the overlying force or pressure in Newtons per metre square, G is the acceleration due to gravity, d = the density of the water and h = the height of the water column.

G = 9.8 m s², d = 1.1 x 10³ kg m³ and h is the depth of water in metres

Hence for a water column of 5,000 m depth the overlying pressure is equal to 9.8 x 1.1 x 10³ x 5 x 10³ or about 5.4 x 10 7 N m² or about 5.7 Million tonnes per metre square.

Here's the after:

$\,\!P=\rho gh$

where
P = the overlying pressure in Newtons per metre square,
$\rho$ = the density of the seawater= 1.1 x 10³ kg/m³,
g = the acceleration due to gravity= 9.8 m/s² and
h = the height of the water column in metres.

Hence for a water column of 5,000 m depth the overlying pressure is equal to 1.1 x 10³ x 9.8 x 5 x 10³ or about 5.4 x 10 7 N m² or about 5.7 Million tonnes per metre square. —Preceding unsigned comment added by Talldave (talk • contribs) 05:20, 1 June 2008 (UTC)

I'm new to Wikipedia editing so excuse me if this isn't done correctly. I believe there is an error in the calculation here. The formula is correct and the calculation of N/m2 is correct but the conversion to tonnes per square metre is incorrect. 1 tonne/m2 = 9.8 x 10^3 N/m2. The pressure at 5000 metres is thus approx 5000 tonnes/m2. This is also intuitively correct if you consider that a cubic metre of water weighs 1 tonne, thus a column of 5000 cubic metres of water stacked on top of each other, which would weigh 5000 tonnes, exerts a pressure of 5000 tonnes over its 1 square metre base. —Preceding unsigned comment added by 93.96.136.2 (talk) 13:02, 3 May 2009 (UTC)

How about a more accurate term?

Why don't we call these waves "thalassoseismic waves"? --  Denelson83  21:08, 6 June 2008 (UTC)

show a map of where they were —Preceding unsigned comment added by 216.220.23.176 (talk) 15:43, 9 October 2008 (UTC)

Too many images

{{editprotected}} The top two images here seem a bit redundant; I think the top one should be taken out, as it is essentially the second one except from a difficult-to-read angle.—Preceding unsigned comment added by 205.200.76.127 (talk • contribs)

Sounds reasonable enough; any objections? – Luna Santin (talk) 21:53, 26 October 2008 (UTC)

Done. -- zzuuzz ^(talk) 22:30, 26 October 2008 (UTC)

Other language than Japanese and Tamil

The only other language than Japanese that has a word for this disastrous wave is Tamil language and the word is "Aazhi Peralai".

Chinese has a term "simplified Chinese: 海嘨; traditional Chinese: 海嘯; pinyin: hǎixiào" for it.--Marcushsu (talk) 16:32, 10 December 2008 (UTC)

Spanish has MAREMOTO, from Latin mare, maria, maris, sea, and moto, movement; akin to TERREMOTO, from Latin terrae (genitive case of the word terra, earth, plus moto, movement) ergo terremoto=earthquake and maremoto=seaquake. —Preceding unsigned comment added by 168.234.217.7 (talk) 02:15, 11 March 2009 (UTC)

Is Deep-Sea Wave Amplitude 300 mm. or 1 m?

The "Causes" section says the amplitude is 300 mm. in the open sea, but the "Characteristics" section says 1 m. for the same thing. Can some knowledgeable person reconcile the discrepancy, or else pick one or the other? Kkken (talk) 10:40, 3 February 2009 (UTC)

kristal stone said hey <no —Preceding unsigned comment added by 66.204.165.126 (talk) 20:11, 11 February 2009 (UTC)

Error in calculation of underwater pressure

{{editsemiprotected}}

I'm new to Wikipedia editing so excuse me if this isn't done correctly. I believe there is an error in the calculation in the section "Warnings and prevention". The formula is correct and the calculation of N/m2 is correct but the conversion to tonnes per square metre is incorrect. 1 tonne/m2 = 9.8 x 10^3 N/m2. The pressure at 5000 metres is thus approx 5000 tonnes/m2. This is also intuitively correct if you consider that a cubic metre of water weighs 1 tonne, thus a column of 5000 cubic metres of water stacked on top of each other, which would weigh 5000 tonnes, exerts a pressure of 5000 tonnes over its 1 square metre base. Mccarcass (talk) 13:10, 3 May 2009 (UTC)

Done I'm not sure how common tonne(weight)/m² is as a term for water pressure, but I think you're right about the conversion. 1 tonne = 1000kg. 1 tonne(weight) = 1 tonne at 1 gravity = 1000kg * 9.8m/s². 1N = 1kg*m/s², so 1 tonne(weight) = 9.8*10³N and 5.4*10⁷N/m² = 5510.2, or approximately 5500. I'll correct the result, but we really should find a reference for the conversion and for the formula. Celestra (talk) 15:22, 4 May 2009 (UTC)

Adding origin of the term in Japanese

In the Japanese page for tsunami there is a short description about the origin of the term "tsunami". Adding this description may become an answer to some discussions on why tsunami are thought to be related to "harbor". A translation (slightly rewritten) from ja article might be following:

The term "tsunami" — "a harbor wave" in old Japanese — originates from the fact that a tsunami, unlike normal waves, caused massive damages in harbors, even though damages were little (or even unnoticeable) on ships offshore (see Characteristics).

In any way, in recent Japanese it is understood as "tsunami", not as a harbor wave. The origin is historic.

If Japanese external references are needed, this (About Tsunami -- Tsunami Engineering Laboratory, Disaster Control Research Center, Tohoku University) or many other resources could be cited. --Y.oiwa (talk) 19:10, 8 June 2009 (UTC)

Article about tsunami

The article about tsunami contains some grammatical errors: the plural of "tsunami" is "tsunami". I speak Japanese fluently, having lived there and being married to a Japanese man for more than 25 years. Please make this correction in the page.

Elmo5159 (talk) 06:01, 21 July 2009 (UTC)

Tsunamite

Encountered this word for the first time today. What does it consist of? Sand and sea creatures presumably? Drutt (talk) 20:52, 9 August 2009 (UTC)

adding a reference to the list of references in the article on tsunamis

I would like to call your attention to the following recently published book.

http://www.hup.harvard.edu/catalog/BERTSU.html

Thanks. —Preceding unsigned comment added by Fisherpost (talk • contribs) 21:48, 30 September 2009 (UTC)

adding a reference to the list of references in the article on tsunamis

I would like to call your attention to the following recently published book.

http://www.hup.harvard.edu/catalog/BERTSU.html

Thanks. --Fisherpost (talk) 21:50, 30 September 2009 (UTC)

Chilean Earthquake Feb. 27, 2010, Pacific Tsunami Warning Center overestimated size of resulting tsunami waves

Warning center learns from miscalculation, Honolulu Advertiser, Gordon Y.K. Pang, Advertiser Staff Writer, Feb. 28, 2010:

‘ . . . DART gauges spread across the sea floor to detect the size of tsunami waves are a fairly new technology, Fryer said. The initial wave reading from the DART gauge showed 25 centimeters, huge for the deep water, he said.

‘"At that point, we went to full Pacific-wide warning," he said. "Part of the reason we had to do that was because although it was huge, we didn't quite know what it meant because we haven't much experience with those. As we get more under our belts, we'll get better."

‘He added: "Fifty percent error, that's OK. That's about the level of accuracy in this game. It will get better."

‘Nonetheless, "with every event the system improves," Fryer said. . . ’

posted by Cool Nerd (talk) 23:22, 2 March 2010 (UTC).

== And sometimes the first wave is not the biggest == this is true but the first wave is generally the largest

'The last wave almost wiped the village off the map', The Irish Times, MARIO NARANJO in Dichato, Tuesday, March 2, 2010:

‘ . . . The first two surges startled the town’s 7,000 residents, who had already been violently awakened by the earthquake that wrought destruction across a swathe of central Chile. But it was the third surge, a huge wall of water, that tore up and smashed houses, swept cars out to sea, and sucked people’s possessions into the sea, destroying more than three-quarters of the town’s buildings.

‘“The last one almost wiped the village off the map,” said David Merino, surrounded by a scene of water-logged destruction in the village, which was among the closest settlements to the 8.8-magnitude quake.

‘It was still unclear how many people died in Dichato, where distraught residents wandered the town trying to salvage possessions and gazing at their ruined homes. . . ’

posted by Cool Nerd (talk) 02:03, 3 March 2010 (UTC).

That is already in the article, "A large tsunami may feature multiple waves arriving over a period of hours, with significant time between the wave crests. The first wave to reach the shore may not have the highest run up". Mikenorton (talk) 22:05, 8 March 2010 (UTC)

Editing permision request

User:Heds 1

• Heds 1 · (talk · contribs · deleted · cross-wiki · wikichecker· count · pages created · logs · block log · lu · rfar · rfc · rfcu · ssp · spi · search an, ani, cn, an3) (assign permissions)

I can contribute a lot more to the causes of tsunami including landslide & asteroid generated events with references (eg. Haugen et al., 2005; Ward & Asphaug, 1999; Ward, 2000) Heds 1 (talk) 13:05, 28 April 2010 (UTC)

This article is semiprotected, for you can edit this article, you must have at least 10 edits. Read more about it here Wikipedia:User access levels#Autoconfirmed users.--Luizdl (talk) 15:48, 28 April 2010 (UTC)

Edit request from 206.174.25.141, 21 May 2010

{{editsemiprotected}} Simple grammatical change requested: Drawback section Currently reads: "If the first part of a tsunami to reach land is a trough called a drawback, rather than a wave crest. The water along the shoreline recedes dramatically, exposing normally submerged areas." [First "sentence" is actually a phrase.] Should read: "If the first part of a tsunami to reach land is a trough called a drawback, rather than a wave crest, the water along the shoreline recedes dramatically, exposing normally submerged areas." 206.174.25.141 (talk) 09:46, 21 May 2010 (UTC)

 Done Thanks for spotting that. Mikenorton (talk) 09:53, 21 May 2010 (UTC)

Pending changes

This article is one of a small number (about 100) selected for the first week of the trial of the Wikipedia:Pending Changes system on the English language Wikipedia. All the articles listed at Wikipedia:Pending changes/Queue are being considered for level 1 pending changes protection.

The following request appears on that page:

However with only a few hours to go, comments have only been made on two of the pages.

Please update the Queue page as appropriate.

Note that I am not involved in this project any more than any other editor, just posting these notes since it is quite a big change, potentially.

Regards, Rich Farmbrough, 20:43, 15 June 2010 (UTC).

question

Is there any chance that the country im living in Ireland be hit by a tsunami and has they ever been one and where would one come from and what would cause it. —Preceding unsigned comment added by 83.70.105.68 (talk) 19:57, 17 August 2010 (UTC)

Sure: Lisbon_earthquake#The_earthquake_and_tsunami. ErikHaugen (talk) 07:52, 19 August 2010 (UTC)

Consistency on the plurals.

I have no idea which word you should use. Tsunami or Tsunamis doesn't matter to me but you should choose one and stick with it. The section discussing the plurals uses the Japanese way, whereas it seems like the entire rest of the article uses the English way. Lilly (talk) 23:18, 4 September 2010 (UTC)

Editing request

please spell "casualties" correctly. Also, the people in Guam believe their island is tsunami proof because of the Marianas Trench. thanks

{{edit semi-protected}}. I want to edit this article. -- Tapail (talk) 07:38, 10 January 2011 (UTC)

Please specify the change you'd like made, and if it's constructive and in accordance with Wikipedia's policies, it will be done. Alternatively, you need only make two more edits – to any page – and your account will be autoconfirmed and you'll be able to edit this article yourself. Adrian J. Hunter^{(talk•contribs)} 11:23, 10 January 2011 (UTC)

Drawback of the 2004 Indian Ocean Tsunami on western side

The article claims that there was no drawback on the western side of the 2004 tsunami but when I searched for a scientific article verifying this I found none (though the wikipedia article quoted at great length without attribution). On the contrary, I found a scientific proceeding which claims that there was a drawback:

The Italian-speaking vice council, Mahad X. Said, standing at the waterfront outside the mosque upon the arrival of the tsunami (Figure 10a), gave a very detailed description of the initial wave sequence. At first, a 100-m drawback was noticed, followed by a first wave flooding the beach. Next, the water withdrew again by 900 m before the second wave partially flooded the town. Finally, the water withdrew again by 1,300 m offshore before the third and most powerful wave washed through the town. These drawbacks correspond to 0.5-m, 4-m, and 6-m depths. The detailed eyewitness account of the numerous drawbacks is founded on the locations of the offshore pillars.

The question is under debate at Physics Stack Exchange:

http://physics.stackexchange.com/questions/6720/why-do-tsunami-waves-begin-with-the-water-flowing-away-from-shore

50.46.72.194 (talk) 03:02, 12 March 2011 (UTC) Carl Brannen

Storm surge is not directly caused by the low pressure of a storm.

It says the low pressure of a storm causes storm surge. While that is true, the statement implies it directly causes it, it does not. The storm surge is caused by winds, those winds caused by the low pressure. —Preceding unsigned comment added by 67.186.62.211 (talk) 05:23, 14 March 2011 (UTC)

The Word Tsunami

Why is the word tsunami in italics all over this article? 65.92.176.38 01:31, 2 April 2007 (UTC)

Who knows. It's fixed now 206.47.141.21 16:25, 2 April 2007 (UTC)

I think there is (or at least was) a convention of using italics for foreign words in English contexts. I've seen it used a lot in books more than a couple of decades old, but it seems to be rarer in modern works. I guess a previous editor was following that convention. (I don't know if Wikipedia has a policy on this). Wardog (talk) 11:16, 16 March 2011 (UTC)

Composed of Han characters?

Someone has written this:

"The term tsunami comes from the Japanese 津波, composed of the two Han characters 津 (tsu) meaning "harbor" and 波 (nami), meaning "wave"."

There are some problems with this really strange formulation:

1. "Han characters" is not widespread usage in English. "Kanji" (from Japanese) and "Chinese character" (an old English-language usage) are found, but "Han character" is not normal usage, except perhaps as an attempt to be somehow politically correct. Unfortunately, the recent insistence on using "Han" instead of "Chinese" is itself politically motivated. There is no reason to pretend that "Han character" is somehow superior to "Chinese character", or even "kanji" in Japanese-language contexts. It is merely an attempt to redistribute semantics in certain politically motivated ways. Unless there are really cogent reasons for avoiding normal established usage -- "Chinese character" (or "Chinese ideogram", etc.) -- there is no reason for this article go out of its way to use the strange name "Han character".

2. In contrast to the attempt to be ultra-rigorous in using "Han character", the same editor is incredibly sloppy in his/her formulation that the word tsunami is "composed" of two characters. In point of fact, Japanese words are not "composed" of Chinese characters. They are written with them. The word 'tsu' is a Japanese word. So is the word 'nami'. The word 'tsunami' is made up of the two words 'tsu' and 'nami'. It is not composed of two Chinese characters. Let me cite an example that illustrates the vacuousness of the "composed of Chinese characters" formulation. The Japanese word for "letter" is tegami. It literally means 'hand paper', and is thus written with the characters 手 and 紙 ('hand' and 'paper'). The Chinese word 手紙 is written with the same characters, but it is read shǒuzhǐ and means "toilet paper". The use of the same characters for words with totally different meanings and totally different pronunciations is a result of the way that Chinese and Japanese make use of the written language (specifically Chinese characters). The words te and kami, and the compound word tegami, are all Japanese words. They happen to be written with the characters 手, 紙, and 手紙. The words shǒu and zhǐ (in Mandarin) and the compound word shǒuzhǐ are all Chinese words. They happen to be written with the characters 手, 紙, and 手紙. To say that these words are "composed" of the characters 手, 紙, and 手紙 is quite erroneous.

I am putting this in the discussion section because this article is protected and does not allow editing. But I do wish that people who take up trendy, seemingly "accurate" or "non-POV" formulations like "Han character" would give a little thought before inflicting these tortuous formulations on Wikipedia articles.

Addition:

3. Oda Mari has come up with a third, even more compelling reason to avoid the above formulation: 津 in Chinese and Japanese has different meanings! Oda Mari has mercifully corrected it.

202.131.238.35 (talk) 02:03, 15 March 2011 (UTC)

I wrote that sentence. I am not interested in Chinese and Japanese languages, I am interested in tsunamis. I know nothing about these "characters", I did not even know if they were supposed to be called "characters" or "ideograms" or whatever. I only needed a term to call them somehow. So, I just followed these links to Wikidictionary: 津 and 波, where these characters are labeled Han characters, and I just followed suit. Paolo.dL (talk) 11:55, 15 March 2011 (UTC)

If you have no interest in the Chinese and Japanese languages, why did you go in and edit? You must have had some reason for being dissatisfied with the original formulation. To go in and "improve" things when you not only know nothing about it, you are not even "interested" in what you are editing doesn't sound like very responsible approach to editing Wikipedia articles.

202.131.238.35 (talk) 01:31, 16 March 2011 (UTC)

You are overreacting. I knew that Wikidictionary calls them Han characters, and the link to Wikidictionary was already given BEFORE MY EDITS. You just did not notice it, but it was already there. I improved the syntax of a pre-existing sentence, and I was interested in that improvement. The sentence did not give the complete Japanese "word". I added the complete word, then I needed a way to say it was composed of two "characters". The meaning of the two characters was already given before my edits. I was interested in this meaning, not in the name of the characters. There's nothing irresponsible in using, for these characters, the same name used in Wikidictionary. It might be wrong, but certainly not irresponsible! Let's not discuss this anymore. If you want to fight this war, do it on Wikidictionary. As for this article, and for most of its readers, what Oda Mari wrote in his/her edit summary is more than sufficient. Paolo.dL (talk) 23:09, 16 March 2011 (UTC)

It's already moot, but I Agree . It appears to be an honest mistake by an editor ignorant of the Japanese language who unwittingly touched a nerve made sensitive by Unicode politics. They are Han characters, but when discussing their meaning, that is language-specific, just like the 4 latin characters "mist" mean different things in English and German. When discussing the Japanese meaning, it is more appropriate to use the Japanese-specific name "Kanji". 71.41.210.146 (talk) 00:20, 17 March 2011 (UTC)

too many pronunciations, pick one

津波tsunami, tsunamis I have put the other pronunciations here no need for Japanese pronunciation, Japanese pronunciation: [tsɯnami]; /tsuːˈnɑːmi/ tsoo-NAH-mee or /suːˈnɑːmi/ soo-NAH-mee) icetea8 (talk) 03:22, 17 March 2011 (UTC)

tidal wave reference

Tidal wave is an older term, First Known Use of tidal wave is 1851 according to merriam-webster [3]. icetea8 (talk) 03:48, 17 March 2011 (UTC)

Edit request: fix broken link

{{editsemiprotected}}

Please make the following edits:

• Move the second-last paragraph from the "Warnings and predictions" section down to "Mitigation". ("It is not possible to prevent a tsunami. However, in some tsunami-prone countries some earthquake engineering measures have been taken...")
• Move the last paragraph down to Mitigation / Natural Barriers. ("Natural factors such as shoreline tree cover can mitigate tsunami effects...")
  • (The above changes are probably most easily made by editing the whole article and moving the headings up.)
• Fix the link in footnote 29, the footnote in that last paragraph, for the BBC article "Tsunami villagers give thanks to trees". The correct URL is http://news.bbc.co.uk/1/hi/south_asia/4269847.stm .
• The date for that article should be corrected to 2005-02-16.

Of course, if you disagree, any subset of these changes is also appreciated. Thank you! 71.41.210.146 (talk) 23:58, 16 March 2011 (UTC)

 Done: excellent suggestions, all done. Thanks for your request. -- gtdp ^(T)/_(C) 17:38, 17 March 2011 (UTC)

Split of Tsunami barrier

I split the Natural barriers section before I realized I was editting a B-Class article. Since I've already made the split, I'm going to claim WP:BEBOLD was forefront of my mind. Truth is, that I overlooked proposing the change because I overlooked the article's class and attention. If anyone objects to the split, feel free to undo. I'm going to continue working on the Tsunami barrier article in the meantime.--v/r - TP 17:29, 29 March 2011 (UTC)

potential source

book chapter made freely available (but not freely licensed) by the publisher: [4] -- phoebe / (talk to me) 00:49, 30 March 2011 (UTC)

Tsunami

What is a good thesis for Tsunami's? —Preceding unsigned comment added by 204.113.97.5 (talk) 20:01, 30 March 2011 (UTC)

Hypothetical designs for tsunami shelter platform and early warning system

If people happen to be within a zone that is inundated by a tsunami, there is either sufficient warning and high places to seek refuge, or there are not. Some combination of a very effective extremely rapid warning system and elevated "escape platforms" may reduce some of the casualties. The platforms would have to be of a sufficient height (or a terraced set of sufficient heights), readily accessible, and large enough for the surrounding population. The platforms would also have to be designed so that oncoming tsunami don't climb the stairs or ramps leading to the protected height. I envision 60 to 80 ft high "tear drops" with a prow pointing to the sea, and a large flat area on top. They could taper gently at the back.

They would become "escape islands" when a tsunami strikes.The warning system would have to be prompt enough to provide people with time to access the platforms.

A warning system would require a well-defined network of sea elevation sensors in the ocean waters some distance out to sea. People would be instructed to wait on the platform for an all clear signal. —Preceding unsigned comment added by 149.136.25.253 (talk) 00:08, 6 April 2011 (UTC)

A couple of nice thoughts, although Wikipedia is not the place for them. (The Wikipedia discussion page is intended for discussion about the structure of the page, not the topic itself.) But as to substance - a comprehensive system of tsunami detection buoys, even a few deep-sea buoys, already exists throughout the Pacific Ocean. Tsunami waves don't "climb" quite the way you envision it so the teardrop structure would have to be reexamined, but escape platforms could potentially be quite doable. You have found a solid entrepreneurial niche, and, even better, one that genuinely betters people's lives. Do some more research, both scientific and business, and then go for it! - Tenebris 20:01, 17 September 2011 (UTC) — Preceding unsigned comment added by 207.112.29.225 (talk)