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On December 26, 2004, at 7:59 a.m. local time, an undersea section of the
Earth's crust slipped along a 700-mile-long fault off the coast of Sumatra,
setting in motion a train of destructive waves called tsunamis that left well over
250,000 people dead or missing. In "Wave That Shook the World," NOVA traces exactly
what happened, and why.
Before 2004, the Indian Ocean's most devastating tsunami was caused by the
titanic eruption of the volcano Krakatoa in 1883. (Immediately following the
original airing on March 29, PBS revisits this earlier disaster with
"KRAKATOA," a 90-minute docudrama.) Causing nearly 40,000 deaths, Krakatoa was
long considered an almost unimaginable catastrophe, until last December's
tsunami showed that humans are more vulnerable than ever to rare but inevitable
natural disasters.
This program tells the minute-by-minute story of the 2004 tsunami, featuring
video footage and scientific analysis of the onrushing waves that spread for
3,000 miles around the Indian Ocean basin. NOVA interviews eyewitnesses,
including one of the few people who survived when a train carrying 1,500
passengers along a coastal route in Sri Lanka was swamped by the waves; and two
men who videotaped the second, more destructive wave that hit their beachfront
bar in Thailand. Thousands had been lulled into a false sense of security after
the first wave passed. Tsunamis, however, usually consist of several waves,
separated by many minutes or even hours, and the biggest can come at any
time.
Some geologists estimate that the earthquake that caused the disaster measured
9.3 on the Richter scale, making it the second largest on record. The quake
occurred near the surface of the seafloor, where one plate of the Earth's crust
is slipping beneath another, creating periodic releases of pent-up energy. NOVA
uses detailed animation to show how the quake raised a portion of the seafloor,
which also lifted all the water lying above it. This movement caused a series
of massive waves that radiated outward from the quake's epicenter at speeds
approaching that of a passenger jet. (For a detailed look at the event, see
Anatomy of a Tsunami.)
Barely a minute after the quake, computers at the Pacific Tsunami Warning
Center in Hawaii picked up seismic signals and automatically notified
scientists. Within a few minutes they had issued a warning bulletin. But they
still did not know the full magnitude of the quake or whether it had triggered
a tsunami. The Center's ocean-sensing gauges are confined to the Pacific, where
tsunamis regularly occur. No similar network or warning system exists in the
Indian Ocean.
Fifteen minutes after the temblor, a colossal wall of water struck the
northwest coast of Sumatra and washed several miles inland, destroying
everything in its path. Over the next few hours, a series of gigantic waves
traveled across the Indian Ocean, killing tens of thousands of people in
Thailand, Sri Lanka, and India.
The degree of destruction is almost impossible to fathom. It was "like the
aftermath of an atomic bomb, maybe worse," says disaster photographer Geoff
Mackley as he surveys the Sumatran coast, site of the earliest waves, which are
estimated to have been as high as 60 feet. The area is littered with debris of
every description, from battered factories to shattered concrete breakwaters to
ships tossed around like toys.
"KRAKATOA" addresses a catastrophe at the southern end of Sumatra, in the
strait separating the island from Java. There, in the late spring and summer of
1883, the volcano Krakatoa came to life with ominous rumblings that culminated
in the largest volcanic explosion ever recorded. The program brings this
legendary event to life with dramatic recreations and computer animation.
The eruption generated a wave that was even more powerful than the tsunami of
2004, although it didn't spread as far and resulted in about 15 percent as many
casualties. (See
Once and Future Tsunamis for more on this and other
deadly tsunamis through history.) Krakatoa itself was obliterated by the explosion, which was heard
thousands of miles away. Airborne debris spread around the world, producing
vivid sunsets for years. Today, a new volcano is rising near where Krakatoa
once stood. This discovery is a stark reminder that, with nature, the question
is not could it happen again but when.
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An Indonesian man looks at a boat left stranded atop a house in Banda Aceh, the provincial Sumatran capital that was desolated by the tsunami.
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