Tsunami postulate
Tsunami postulate is assumption about the height of tsunami that may happen in certain region.
The tsunami postulates are elaborated on the statistical analysis of the measurement of elevation of water during previous tsunamis. The modeling of propagation of the long-length waves after an earthquake and/or an underwater volcano eruption also can be used.
The tsunami postulates are used as basic assumptions for the projecting and construction of the costal environment, including ports, dams or nuclear plants, that seem to be especially vulnerable to a flooding: due the decay heat, they require permanent source of energy after the shut-down of the [chain reaction]] for the safe cooling.
Tsunami postulates as scientific concept
The concept of the tsunami postulates allow to separate, divide the problem of safety to the two parts:
1. Sciencific part, that includes the geophysical analysis of the conditions and probability of appearance of a huge tsunami. At this part, the postulates are generated.
2. Engineering part, that include the design of the coastal construction, that resist the tsunami of the altitude postulated as "maximal possible".
The careful observations of the level of precedent tsunamis for several kilo-years could provide good base for the statistical analysis and the weighted predictions based on the probability theory Unfortunately, the systematic measurements of the level of tsunamis began only in century 20, therefore, there are very few data about huge tsunamis. Some additional information about levels of historical tsunamis can be extracted from the special stones installed centuries ago, that specify anything similar to Do not build the house in a place that is lower than here (see 此処より下に家を建てるな). This information goes deep into centuries, but it is very sparse.
the lack of careful observation of level of tsunamis during the Human history seems to be a reasonable solution and a useful tool in the organization of the coastal environment.
Legal aspect of the Tsunami postulates
The Tsunami postulates helos the geophysicists and engineers to make weighted decisions, as they allow to separate the responsibility.
If the Tsunami level happens to be above the height postulated, the guilt should be attributed to the geophysicists and experts who did not estimate well the conditions in the region.
If the Tsunami level happens to be below the height postulated, but still causes serious destructions (or disaster) the guilt should be attributed to the constructors who made an error designing the environment for certain level of tsunami.
In particular, for the case of the Fukushima disaster, the report by NAIIC from 2012 July 5 - 2012/10/25 [1] declares: NAIIC has verified that at the time the Great East Japan Earthquake occurred, the structure of the Fukushima Daiichi Nuclear Power Plant was not capable of withstanding the effects of the earthquake or the tsunami. Nor was the nuclear power plant prepared to respond to a severe accident. In spite of the fact that Tokyo Electric Power Company (TEPCO) and the regulators were aware of the risk from such natural disasters, neither had taken steps to put preventive measures in place. This was the fundamental reason for the accident; it could have been prevented if these matters had been attended to appropriately.
It seems, that in the case of the Fukushima -1 nuclear plant, the tsunami postulate had been updated (increased) when the exploded nuclear plant was already built-up.
References
- ↑ National DIet of Japan Fukushima Nuclear Independent Investigation Commission. Main report. This English translation of the report is a direct translation of the main report. 2012/10/25. NAIIC has verified that at the time the Great East Japan Earthquake occurred, the structure of the Fukushima Daiichi Nuclear Power Plant was not capable of withstanding the effects of the earthquake or the tsunami. Nor was the nuclear power plant prepared to respond to a severe accident. In spite of the fact that Tokyo Electric Power Company (TEPCO) and the regulators were aware of the risk from such natural disasters, neither had taken steps to put preventive measures in place. This was the fundamental reason for the accident; it could have been prevented if these matters had been attended to appropriately.
http://tsunamisociety.org/STHVol20N5Y2002.pdf George Pararas-Carayannis. EVALUATION OF THE THREAT OF MEGA TSUNAMI GENERATION FROM POSTULATED MASSIVE SLOPE FAILURES OF ISLAND STRATOVOLCANOES ON LA PALMA, CANARY ISLANDS, AND ON THE ISLAND OF HAWAII. Science of Tsunami Hazards, Volume 20, Number 5, page 251 - 277 (2002 ) Based on available geological data and a review of historical events, the present study further examines the likelihood that such massive volcanic flank failures can indeed occur in the foreseeable future, as postulated.