On 26 December 2004 a
tsunami occurred in the Indian Ocean, causing terrible damage to the countries
surrounding the Ocean and the islands around it. A tsunami is a series of huge
waves which are caused by a volcano or earthquake occurring under the ocean.
The effects of the earthquake on the ocean cause water to move on a huge amount
which, when it reach the shore, has a huge effect on everything in its
way.
This tsunami caused by
abduction occurring between two tectonic plates on the ocean floor. The
Indio-Australian Plate below the Eurasian Plate sinks into the face of the
earth. This caused the sea-floor to goes up and down, causing the earthquake
with above 9 grades on earthquake scale and setting off a series of tsunamis
along the coasts of all surrounding countries. The epicentre of the earthquake
was between the island of Simulate and mainland Indonesia. The Indonesian
tsunami is thought to be the 3rd biggest earthquake of all time, killing
280,000 people in 14 countries. The earthquake itself also had the longest
duration time ever recorded, of between 8.3 and 10 minutes and it caused the
entire planet to vibrate by around 1cm.
Of the fourteen countries
affected Indonesia was the worst one with over 160,000 dead; followed by Sri
Lanka with 35,000; India with 18,000 and Thailand over 8,000, moreover 1.6
million people were moved from their homes due to the huge damages happened. As
well as local residents and tourists from abroad were also killed as many of
the areas affected were very popular with tourists. Over 1,000 tourists from
Germany and Sweden lost lives along with another 1100 plus from across the rest
of the world.
Many people have asked why
there was little time to evacuate areas that were under threat, and why so few
people in these areas knew what was happening until it was too late, even
though there was a period of several hours following the earthquake, before the
impact on land of the tsunami, almost all of the victims were totally unaware
of what was coming. there were no tsunami warning systems in the Indian Ocean
to detect any problems and therefore warn citizens that they needed to
evacuate. While detecting tsunamis is not an easy science, it is possible, but
it is expensive to set up the communication systems needed to warn people,
especially in such a poor part of the world. Fortunately, following the
disaster, the United Nations initiated the set up of an Indian Ocean Tsunami
Warning System; and there is now a large network of graphic centers, national
warning centers, agencies and deep-ocean stations in place across the Indian
Ocean to detect any potential tsunamis and send out warnings to communities.
In the case of the
Indonesian disaster, while the tsunami was in the open ocean the waves were
less than one meter high which would not cause any alarm at all. However, by
the time they had reached the coast, the waves had reached up to 30 meters in
height and were travelling at speeds of up to 800 km per hour. It is easy to
see why the waves caused such total mess, wiping over 140,000 homes and spreading
3km inland, carrying salt water with them. One of the most weirdest features of
the tsunami is the fact that in the few minutes before the tsunami hits the
coast and moves ashore (so some time after the earthquake), the sea often goes
far out – like a receding tide – and leaves a large area of exposed beach. This
happened in the Indonesian case, exposing around 2.5km of beach that would
normally have been covered by the sea. Obviously this caused people, especially
children, to go onto the beach and collect coral and fish. Sadly this was the
most dangerous thing to do as the tsunami causes the sea to swell and rush back
onto the coast without warning, almost always sweeping away anyone in its path.
Very fortunately, on the island of Simulate which was very close to the
epicenter, most of the islanders knew what was happening. This is because the
ancestors of the citizens of the island had passed on their knowledge and told
stories of a similar incident that had occurred in 1907. This meant that the local
people recognized what the receding ocean meant; and moved to the safety of the
inland areas. This factor shows that if people in all of the areas that were
affected had been better educated in what can happen before a tsunami; and
therefore knew the warning signs, perhaps more lives could have been saved.
However, not all tsunamis
cause the sea to recede and different parts of the coast affected by the same
tsunami may show different behaviors, so this is of course not the whole story.
In some incidences there are no coastal warning signs at all and the sea will
just swell and produce enormous waves with no retreat, meaning people have
little time to flee to safety. Therefore my take on the issue is that the only
factor that would have given people a chance to flee would have been a
comprehensive early warning system. A full warning system under the ocean would
have been able to detect the earthquake under the water and a proper
communication system would have allowed the surrounding countries and communities
to receive warnings to evacuate. The fact that there was a delay of several
hours between the earthquake and the tsunami first striking the coast, means
that most if not all of the people who were killed could have evacuated to
safer areas. As it was known to be an area that could suffer from earthquakes
or tsunamis, the fact that these systems were not in place can only be put down
to economic reasons. Fortunately the early warning systems are now in place and
hopefully this level of tragedy will not happen
again.
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