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| Sunday, 15 January 2006 |
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Features |  |
| News Business Features Editorial
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Operation "Giant Wave" :
Tsunami' or 'Seismic' sea wave 'Lt. Col. Susantha Seneviratne, RWP, RSP, Psc, Msc (def)-retd.
"Years of effort collapsed within seconds" - A victim of '12/26' "To reside in a suitable locality"... - The Buddha (the 'third' highest blessing according to 'Mangala' sutra) When a powerful earthquake strikes on land, the earth trembles for miles around, and destruction can be very high. If the quake occurs underwater, direct damage is not so severe. But, undersea quakes always cause enormous damages even thousand miles away as that of disaster of '12/26'. Vibrations emanating from an earthquake can generate a series of waves. They fan out from the earthquake's epicentre, endangering land masses far away. A frequent heard term for these destructive water movements is 'tidal wave'. But, the tides have nothing to do with this type of wave, so the term is inaccurate. For this reason, scientists prefer to use 'seismic sea wave', or, more commonly 'tsunami'. This is a Japanese term, which interprets 'harbour' and 'waves' by its syllable of 'tsu' and 'nami', respectively. Over the past few centuries, Japan has been struck by these Tsunamis more than any other country. They can also be caused by underwater volcanic eruptions or by giant landslides on an ocean bed. Whatever the primary cause, it may be, the effect is the same: 500 M/700KMPH Japan is most frequently hit by tsunamis while Indonesia by regular strikes. According to available historical records, it was in 1757 the first seismic sea wave strike has occurred in the North Atlantic Ocean, causing damages and deaths over 100,000 people in Portugal and Morocco. In 1896, a great earthquake 700 M/980KM out to sea from Japan caused a series of tsunamis. These engulfed Japan's northeast coast, killing more than 27,000 people. The most destructive strike then and now the second largest after '12/26' took place in 1883, when the volcanic island 'Krakatoa' in Indonesia (then East Indies) erupted. After the explosion, waves as high as 100 feet swept over nearby islands and killed more than 36,000 people. The strike on the Hawaiian Islands on April 01, 1946 is a classic example of the immense power contained in seismic sea waves. A massive underwater quake occurred more than 2000M/2800KM to the north of Alaska. Almost four hours later, a series of waves began to hit Hawaii. By moving a distance of 2000M/2800KM in four hours, the waves reached the speed more than 500M/700 KMPH. The entire day of April 01, Hawaiian Islands continued, to be struck by this series of waves. In 1952, a tsunami hit 'Kuril' Islands near Japan; in 1957 another strike was reported near Alaska; in 1960, Chile was struck by a wave, killing 2300 people. History thus contains many incidents of seismic sea waves. One of the earliest, which occurred during the 4th century in the Mediterranean Sea, is reported to have drown thousands of Egyptians. Indications Seismic sea waves do not pose any danger to a ship sailing on the horizon. The wave may be one or two feet high in the open water. But, in the shallow water and the wave when approaches land, its height increases dramatically. Before a seismic sea wave strikes the shoreline, an absolute 'ominous' calmness can be observed. Along the shoreline water begins to withdraw much further out to sea than its limit at low tide. After a little while, a huge wall of water comes surging in from the sea moving at very high speed. When it strikes the shore, it devastates everything in its path. Within few seconds/minutes another wave strikes the shore. Thus, it can come as a series of waves one after another and is usually comprised seven to nine waves. Of these, the second or, and third or, and fourth could be the most powerful and worst. As the wave approaches the shoreline, one could hear a kind of hissing sound similar to that of a locomotive steam engine, which discharges its steam. But, the sea behind the wave is calm, flat and serene and a ship on the horizon can detect a slight motion of water. Land Configuration The brunt of seismic sea waves, first hit the shore and then the mainland. Hence, the configuration of shore/coast line plays a vital role depending on the direction of movement of these waves. Besides, natural coral reefs, sand spits, higher grounds, etc provide ideal breakwater to reduce the destructive power of such waves. At the same time, enclosed water bodies, harbours, bays, etc are sensitive to higher damage from onrushing waves and therefore townships should not be planed to set up close to such land features. Damage caused to Galle city by '12/26' is a typical example; onrushing violent waves that travelled from south and southeast directions, striking the shoreline, which is curved into the land towards north and east (Matara), made water collision, compressed, funnelled and gushed through the heart of the city where the bus stand was situated. However, it is important that a 'research' on how the configuration of shoreline stretching from north to south withstood these destructive waves, be conducted for education and appropriate protective measures to be taken on ground. Warning The US, following Hawaiian disaster of 1946 established Pacific Ocean seismological center to warn, of oceanic/underwater earthquakes that occur thousands miles away. It can determine the source of earthquake and its magnitude; thus it alerts areas that may be endangered by the waves. This warning system was successful in saving all human lives but properties when another seismic sea waves hit the Islands in 1952. However, it was not, so powerful as the waves of 1946. Like earthquakes, the seismic sea wave strikes cannot be prevented; but with timely warning and proper evacuation process, loss of lives can be precluded. By establishing townships and habitable localities, taking full advantage of natural ground (terrain) and configuration of shoreline and maintaining natural barriers, such as coral reefs, sand spits, etc it can protect both human life and properties. But, it must be remembered that earthquakes can occur at any time; local warning receiving center(met dept) must be watchful in the night than daytime; because in a country like Sri Lanka most of agencies of both state and private involving in carrying information to public, such as media are in active operation, only during day. Even the police stations and the military, sometimes may not be on full alertness as day, except those in the operational areas. Therefore, dependence solely on radio and telephone communication will not be sufficient. A separate national electronic / electrical warning /alarming system network, especially dedicated for all emergencies must be introduced, in conjunction with the state and private communication agencies. Role of Military The primary role of military is to defend the country in war/combat; while the secondary being to protect the country from both natural and man-made disasters. In all cases, foresight is necessary to pre-empt such situations turning to worst. Like in warfare, natural disasters must be 'anticipated'; to identify suitable actions to be carried out; before, during and after. For this, action plan needs to be implemented by all three services and they must be located at a 'stand off' distance to react accordingly; tasks they have to undertake are so arduous under emergencies and therefore they may have to be executed by a combined/joint effort, harnessing the capability of each service. This will require, a unified command structure, which was a longstanding need not only for natural disasters but also the on-going conflict and future wars/combat. Strategic positioning of military bases, localities, etc to carry ut 'Joint Military Tasks' (JMT), along the costal belt of Sri Lanka is mandatory. Although a disaster management center has been established, their output could be limited to 'offices' when immediate action is essential to be initiated on ground. So, there is no institution other than military, which is capable and efficient for this purpose. As the secondary role of the military and being the only agent, which keeps their eyes and ears open 24 hours, thus having capability of passing timely information and executing immediate action on ground, the military must function according to a National Strategic Defence Initiative Program (NSDIP); so that they can handle both natural disasters and conflict environments, effectively than the present. Philosophy The cause of seismic sea waves is underwater earthquakes and volcanic eruptions; possible fall of giant meteorites can also generate power conducive enough to cause seismic/tsunami waves. These can take place, due to the discharge /release of various energies, which could be the 'end result' of constant motion of electrons in solid, gas, and liquid; under the conditions of pressure, heat, cold, light etc that keep the cycle of existence of world /universe /galaxy maintained. Some energies have been instrumental in giving birth to everything on this planet. The reaction of electrical and electronic forces, which generate energies is called 'natural phenomena' (Dhamma niyama) according to Buddhist philosophy but, it does not understand merits and demerits; nor does saints and sinners; it eliminates everything that obstruct its path. To avoid this, man has to take all the precautions intelligently. So, can 'Karma' alone be blamed? The '12/26' is the 'costliest ' lesson for both those, who were not affected and the survivors to understand the 'ultimate truth' in this world according to what Buddha has discovered in his philosophy- the sublime and unique 'invention', which should not be regarded as a religion. Everything on this planet exists according to this invention, which is being authenticated by the 'findings' of modern science from time to time. |
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