The Boxing Day earthquake and tsunami that occurred in the Indian Ocean were one of the deadliest in modern history. It took place on 26 December 2004 and killed at least 220,000 people including the destruction of property worth billions of dollars (Bondevik, 2008). The areas hit by the tidal waves were Sri Lanka, Indonesia, India, The Maldives, Thailand and the western coast of Somalia. This tsunami measured a magnitude of between 9.1 and 9.3 becoming the third largest earthquake ever to be recorded on a seismograph. It was a Megathrust quake.
Such an incident occurs when a tectonic plate gets subducted by another. The Pacific Ocean has numerous zones of seduction. For this reason, tsunamis are more common in the Pacific, especially near Japan. In fact, the word "Tsunami" is of Japanese origin. It is a portmanteau of two words "Tsu"- meaning harbor and "nami"- meaning wave. Therefore, countries like Japan and Chile are more prepared for such earthquakes and tsunamis (Kelleher & McCann, 1976). In the Indian Ocean, there is a seduction zone west of Indonesia where this earthquake occurred. However, the Indian Ocean does not get earthquakes frequently enough to gain recognition as a hotspot. Smaller earthquakes do occur along the Indonesian line but rarely spread due to the large sea area (McCloskey et al., 2008). This, therefore, is the reason most people living along the Indian Ocean coasts had no information about tsunamis. In this case, the Indian plate got subducted by the Burma Plate.
One major factor that made the earthquake more devastating is that the coastal populations were increasing. The tsunami struck on Boxing Day, a time when the coastlines were occupied by holiday makers from all over. Had some of the people In Sumatra felt the earthquake, they would have reacted to it. However, this wave travelled a long way striking countries that never felt the quake. Those in Thailand and Sri Lanka did not have a clue of what was coming their way. The same period is also a peak tourism period for Thailand and other nearby countries. This means that the beaches in those areas were at their busiest compared to all other times of the year (Synolakis & Bernard, 2006).
One major tsunami that has hit the area in recorded history occurred on 27th August 1883 hitting Krakatoa, Indonesia. The volcanic island erupted and collapsed killing over 36,000 people. Most died from the resulting tsunami and the explosion. Sea water rose more than 140 feet high and carried over 600, ton coral blocks. These wiped some villages along the coast of Java and Sumatra. It is among the historically most destructive tsunamis (Latter, 1981).
While earthquakes cannot be predicted and forecast, they can be rapidly pinpointed. Furthermore, if the appropriate equipment is available, the formation of huge tidal waves can as well get detected, and their likely paths predicted and tracked. In the Pacific Ocean, a tsunami warning system has always been in existence since the 1940s. It got a substantial upgrade after a huge tidal wave hit the coast of Alaska leaving more than 100 people dead. The warning system consists of seismological instruments which register tremors and a network of sea level gauges. In addition to these, the system includes deep-sea sensors linked to full-time monitoring stations in via satellite. These stations are in Hawaii, Japan and Alaska. Through the use of computer modelling, seismologists can accurately predict the likely pathways of tsunamis and their possible impacts (Titov, 2005).
The Indian Ocean, however, lacks such a system. Of the 11, nations hit by the 2004 disaster, only Indonesia and Thailand belong to the Pacific Ocean Tsunami Warning system. The other countries had seismological stations but were not efficient enough. In fact, it was the Pacific warning system that detected the Indian Ocean earthquake (Merrifield et al., 2005). One of the seismologists, Charles McCreery, claimed they received the signals but had no sea-level data to detect or measure the tsunami. They also had no system for sending out a warning. McCreery is the director of the U.S government’s Pacific Tsunami Warning Centre (Kerr, 2005).
References
Bondevik, S. (2008). Earth Science: The Sands of tsunami time. Nature, 455(7217), 1183-1184.
Kelleher, J., & McCann, W. (1976). Buoyant zones, great earthquakes, and unstable boundaries of subduction. Journal of Geophysical Research, 81(26), 4885-4896.
Kerr, R. A. (2005). Failure to gauge the quake crippled the warning effort.Science, 307(5707), 201.
Latter, J. H. (1981). Tsunamis of volcanic origin: summary of causes, with particular reference to Krakatoa, 1883. Bulletin volcanologique, 44(3), 467-490.
McCloskey, J., Antonioli, A., Piatanesi, A., Sieh, K., Steacy, S., Nalbant, S. & Dunlop, P. (2008). Tsunami threat in the Indian Ocean from a future megathrust earthquake west of Sumatra. Earth and Planetary Science Letters, 265(1), 61-81.
Merrifield, M. A., Firing, Y. L., Aarup, T., Agricole, W., Brundrit, G., Chang‐Seng, D. & Magori, C. (2005). Tide gauge observations of the Indian Ocean tsunami, December 26, 2004. Geophysical Research Letters, 32(9). Retrieved 29 March 2016, from http://onlinelibrary.wiley.com/doi/10.1029/2005GL022610/full
Synolakis, C. E., & Bernard, E. N. (2006). Tsunami science before and beyond Boxing Day 2004. Philosophical Transactions of the Royal Society of London A: Mathematical, Physical and Engineering Sciences, 364(1845), 2231-2265. Retrieved 29 March 2016, from http://rsta.royalsocietypublishing.org/content/364/1845/2231.short
Titov, V. V., Gonzalez, F. I., Bernard, E. N., Eble, M. C., Mofjeld, H. O., Newman, J. C., & Venturato, A. J. (2005). Real-time tsunami forecasting: Challenges and solutions. In developing tsunami-resilient communities (pp. 41-58). Springer Netherlands. Retrieved 29, March 2016 from http://www.pmel.noaa.gov/tsunami/Dart/Pdf/titov_small.pdf
