Artigenda
World Tsunami Awareness Day
When: Annually, November 5.
World Tsunami Awareness Day is on November 5 and was the result of United Nations Resolution 70/23 (2015). This is a day dedicated to raising awareness about the dangers and effects of tsunamis. In addition, the day is also meant to emphasise the importance of early warning systems.
What is a tsunami?
The word tsunami is derived from the Japanese words tsu, harbour, and nami, wave. It refers to an extremely high wave that floods a section of land along the coast at an unexpected moment. In most cases, these high waves or waves are caused by seaquakes. In other cases, they can be caused by breaking ice or the collapse of rock formations. The latter occurs in fjords, for example.
As the wave gets closer to land, its strength increases. As a result, the initial wave is sometimes not even perceptible. Contrary to what most people think, it is not a tidal wave or tidal surge.
Besides seaquakes, breaking ice or the collapse of rocks, tsunamis can also be caused by volcanic activity below sea level or, in very rare cases, a meteorite impact.
2004
The tsunami of Sunday 26 December 2004 may be considered the most catastrophic tsunami in modern history. It resulted from a seaquake in the Indian Ocean, about 160 kilometres west of the Indonesian island of Sumatra. This seaquake had a magnitude of 9.3 on the Richter Scale. Had it occurred on land, the impact on land would have been huge. This sea quake is considered the fifth worst quake at sea since 1900. Its force was felt as far away as Bangladesh and Thailand.
The quake did not create a tsunami but created three waves. They spread in different directions across the Indian Ocean. Their speed was about 900 kilometres per hour. Once they arrived on land, the water could reach a height of up to 10 metres. The power of the water was all-consuming.
That which is central on a day like today: a warning system, was not there in many areas. At least not in the Indian Ocean. Such a system did exist in the Pacific. This led to more than 180,000 people losing their lives. Had this warning system been in place, it is incidentally questionable whether it would have been possible to get everyone to safety in time.
Most of the casualties occurred in Indonesia (at least 130,000 people). By far the most casualties occurred in Aceh province. Eighty per cent of the capital Banda Aceh, for instance, was destroyed. Besides Indonesia, Sri Lanka was also hit hard. Besides the 38,000 official deaths, there were other problems. Landmines in the area that had once been dug in emerged and caused additional casualties and injuries.
Besides these two countries, people were also killed in Thailand, Myanmar, India, Bangladesh, Malaysia and Singapore. The tsunami even caused casualties on the other side of the ocean. Think Maldives, Seychelles, Reunion, Kenya and Oman.
Besides the countries’ population, foreign workers and tourists were also killed. For example, a total of 36 Dutch nationals were killed and another 52 from the Netherlands were injured. Yet that number was not as high as the number of Swedish victims: 543 people died. Twelve people would remain missing forever. In Belgium, ten deceased compatriots had to mourn and one person went missing.
The 2004 tsunami showed how important a warning system was. Another tsunami in 2006 that hit the coast of India ensured there were no casualties.
Other things to think about
On this day, we think about such issues. Besides a warning system, there are of course other things to think about. How useful is it to apply certain architecture in certain areas that could theoretically be affected by tsunamis? What might be the impact on societies and how often do tsunamis occur? They cannot be prevented, but their impact is something that can be looked at.
