The op-ed piece below seems to makes some good points. The one that I can best understand is that we should look very far back to natural disasters in Earth's history to get a better understanding of current and future disasters. Without doing so, it is most likely that we will again be unprepared for another epic event.
December 28, 2004
BIG earthquakes occur infrequently, but when they do they usually
come unexpectedly and with horrendous power. It is, of course,
dangerous to live in an earthquake-prone area, but what area in the
world can we say is earthquake-safe? Surely the people in the
Mississippi Valley feel they are safe, as do the people in New York
City. Yet, New York has a fault line going across 125th Street...
OP-ED CONTRIBUTOR
When Nature's Wrath Is History's Reminder
By DENNIS SMITH
SCIENTISTS,
like art teachers who have not mastered anatomy or drawing, often
assume that what they do not know is not important. And, when it comes
to earth science, what they do not know is the pattern of geologic
time, particularly what has happened beneath the ground in the 4.5
billion years that we assume the earth has existed. What have been the
consequences of large waves and water movement to whatever life existed
on its surface?
Humans might know that the universe is theorized to be 15 billion
years old, or that the Milky Way was formed 13 billion years ago, but
the way we feel about ourselves in relation to a 4.5 billion-year-old
earth is not much different from the way indigenous people studying a
night sky might have felt about themselves anywhere on earth 10,000
years ago. The subject of what can possibly happen on earth is simply
too big for most of us to handle if we are to continue to be an
optimistic race. And so we hope for the best.
Yet there are some things we should be thinking about in a more
serious manner. There are facts that we should not let pass into an
obscure scientific history, for remembering them will undoubtedly help
ensure a safer future for all on our planet. This is harder than it
sounds.
We have a tsunami warning system in the Pacific Ocean because, in
recent history, we've experienced tsunamis there. We don't have a
similar system in the Indian Ocean. This has something to do with the
technologies developing nations can afford, of course, But it also has
to do with the fact that our experience with the giant waves in this
region is less immediate. Yet the single worst explosion in our known
geologic history - an eruption of a 20-by-60-mile caldera some 71,000
years ago - occurred on Sumatra, just 100 miles from the epicenter of
Sunday's earthquake.
The earlier eruption left a 10,000 square-mile sheet of volcanic
rock, more than a thousand feet thick, and so filled the sky with ash
that it probably created our last ice age. Still, the eastern Indian
Ocean is thought to be an area of infrequent tsunami activity.
Earthquakes as a rule occur at the ridge of land and water, where
plates usually meet and either slide, thrust or pull apart, releasing
awesome power. But there are exceptions.
Americans believe that earthquakes are a West Coast problem. But the
largest earthquake ever in the United States that we know of, probably
at least as large as the one that destroyed most of San Francisco in
1906, occurred in the area of the Mississippi Valley in 1811. Boats
were thrown over in the river and people drowned. Whole islands simply
disappeared. This earthquake, and its aftershocks a year later, were so
destructive that Congress passed the first federal relief act in 1815
to support the farmers whose previously healthy and farmable land was
turned to swamp, sand and mud.
The quake covered a much larger area than the San Francisco
catastrophe, but fewer people were killed, for in 1811 the area was
sparsely settled by fewer than 10,000, most living in log houses that
would have sustained the shaking well. However, the seismological
activity that caused it has never been explained in definitive terms.
Scientists speculate that the earth here tried but failed to
separate 600 million years ago, creating a weakness of some kind
beneath the ground. The United States Geologic Survey vaguely refers to
the area as a plate boundary zone, which simply means that the agency
doesn't know if there are plate boundaries in the vicinity. But we do
have historical evidence of many substantial earthquakes in a wide area
of the southern Midwest, from St. Louis to Memphis - an area where more
than 10 million people live today.
The greatest cliché in geology is the question, Can it happen again?
Sure. Will it happen again? Well, nature is never overdue, and we
simply don't know. The earth has had many configurations of land, water
and living inhabitants over the ages, and if we think of an
earth-changing event as being "overdue," we are failing to understand
geologic time. It is mind-boggling to think that only 200 million years
ago the earth was one gigantic continent, and one can only imagine the
explosions that broke it into today's continents. The plates beneath
these continents continue to creep, and they don't need an earthquake
to move them along.
We know that Baja California is moving away from Mexico at the rate
of two inches a year - and that it has been doing so for four to six
million years. We know that Europe is moving away from the United
States at the rate of one inch every year, and that Maui is moving away
from South America at the rate of three inches a year. Geodesy is the
science of the shape of the earth and, with the advent in the last
decade of global positioning systems, the geodesists in future will be
able to map every movement of the land and sea with authority and
exactitude.
Our observation and reporting periods cover far too brief a period
of time to allow us to see any pattern. What's more, there are physical
realities in our world that we are not paying attention to. For
instance, in 1971 an earthquake of 6.4 magnitude occurred in the San
Fernando Valley in California. It occurred on a fault that had not been
known to exist, and so surprised scientists, as well as the 80,000
people who lived there.
At one end of this valley is the Van Norman Dam, which lost 30 feet
from its top, and tons of water, during the shaking. Behind it is a
reservoir larger than the one that created the famous Johnstown, Pa.,
flood that killed 2,200 people in 1889. Given the damage, cracks and
weaknesses that resulted, engineers concluded that the dam would have
collapsed altogether had the quake lasted another eight seconds. Today,
almost half a million people live in the valley.
Sunday's tragic earthquake occurred miles beneath the Indian Ocean,
and despite its 9.0 magnitude it was hardly felt in Indonesia, and not
at all in Sri Lanka. Yet the water displacement caused by the thrusting
of the Indian plate beneath the Burma plate created 30-foot waves that
were to kill people on the African coast more than 3,000 miles away.
This distance may seem hard to believe, but after the Great Chilean
Earthquake of 1960, tsunamis traveled more than 6,200 miles to Hilo,
Hawaii, where they killed 61 people and destroyed many buildings with
waves of more than 35 feet.
Oddly, a tsunami cannot be felt as it passes ships on the open
ocean, for the wave is usually small, one to two feet, and traveling
very fast, as fast as airliners. It is only as it approaches shallow
water that it begins to break; as the bottom of the wave slows, the top
keeps traveling at the higher speed and increases in height, hitting
landfall at 30 to 40 miles an hour. In 1958, an earthquake in Lituya
Bay, Alaska, caused a landslide into the ocean that created a tsunami
1,720 feet high, a wave that could have swept over the Empire State Building. Fortunately it headed into a wilderness area and did not travel across the ocean to Hawaii or Japan.
The possibility of great landmasses falling into the ocean is always
with us, and recently scientists found vertical fault lines through a
volcano on La Palma, one of the smaller and more westward Canary
Islands. The volcano has a crater about five miles wide and a half-mile
high, and erupts about every 200 years. The last eruption was in 1948,
but the newly discovered fault lines have convinced some scientists
that eventually the huge crater will break apart and slide into the
ocean, bringing more than a half-trillion tons of rock with it.
Since tsunamis are created in proportion to the amount of land that
has fallen into the water, this event would likely create a wave mass
never before known to written history, many times bigger than the wave
at Lituya Bay. The wave would diminish a little as it crossed the
Atlantic, but if it hit the Atlantic Seaboard it could be higher than
the skyscrapers of Boston, New York, Washington and Miami. Scientists
do not know if it will take one, four, or 10 eruptions to separate the
landmass, only that the separation is inevitable.
The only good news is that volcanoes usually send signals before
they erupt, and it would take eight hours for the wave to travel from
Africa to the United States' eastern shoreline. It is not sufficient
time, however, to move all the people who would be in its path. In any
event, surely the mountain on La Palma should be reduced in size, to
lessen the impact should it ever slide into Atlantic. But, who will pay
for such a huge reduction of a landmass?
A cactus flower colourized and reflective tool used. I thought it looked sort of tribal. 
