Top banner
MY AMERICAN SCIENTIST
LOG IN! REGISTER!
SEARCH
 
RSS
Logo

MACROSCOPE

Spectator at the Disaster

Nature in violent action can be spectacle, tragedy and object of scientific wonder all at once

John Dvorak

I remember the moment when I heard the first report. The date was February 26, 2010. I was at home listening to the tease for the late-night news on television. The news anchor, in a clear and slightly exaggerated tone, announced that a major earthquake had struck Chile. A single thought formed instantly in my head—tsunami!

2011-01Macro-DvorakFA.jpgClick to Enlarge ImageTo those of us who live on islands in the middle of the Pacific, the thought is never far off that a distant earthquake might generate a sea wave that races across the ocean, runs up on shore and sweeps away a community. In Hilo, Hawaii, where I live, tales are told of such a wave in 1946, generated by an earthquake in Alaska. The onslaught began as a pull-back of the sea. Within minutes, those who had gathered along the edge of the strangely emptied Hilo Bay witnessed the sea return as a wall of water. The great wave slammed into a row of buildings that outlined the edge of the bay, then plowed those buildings into the buildings on the other side of the street. Ninety-six people drowned. The area swept vacant by the wave is now a city park where kids play soccer.

The next earthquake-generated wave to hit Hilo was in 1960. A friend who was then a teenager told me that as soon as he and his pals heard that a wave was rushing toward the island, they hustled down to the edge of Hilo Bay to watch it come in. They stood on a small iron bridge close to the shoreline positioned no more than a few feet above high tide. The first wave arrived on schedule and passed under the bridge. Twenty minutes later, a second wave arrived and did the same. Disappointed, my friends and his pals left and went home. Later, a third wave arrived. This one crested fourteen feet over the bridge. Seawater surged as far as a mile inland. Sixty-one people died. Hundreds of homes and businesses were destroyed.

The 1960 wave was generated by an earthquake in Chile. On the night that I heard the report of the latest Chilean quake, local news crews assembled outside the building that houses the Pacific Tsunami Warning Center, located in Honolulu. A spokesman stood outside before a cluster of microphones and informed the public that a large earthquake had just occurred in Chile, similar to the one in 1960, and that a Pacific-wide tsunami was possible. Nothing more would be known, he said, for at least a few hours. By then, the anticipated wave would have passed a buoy tethered in the ocean and designed specifically to detect such waves.

With nothing more to learn, I went to bed.

I awoke at five o’clock the next morning and turned on the television. There it was—the scene I had imagined for years. The same spokesman stood in front of the warning center, reading an official statement. A wave had been generated and was spreading across the Pacific. He then read a list of the times the first wave was expected to arrive at specific places around the islands. The first wave would arrive in Hilo Bay at 11:19 A.M. I woke my family and we made plans to watch the event.

By nine o’clock we were standing on a hillside about a mile from the shoreline at a place that offered an excellent view of the bay. The weather was clear and sunny. It was Saturday, so there were no concerns about children in school. We were standing in a crowd of other families.

Among those in the crowd were many who lived near the coastline in areas that might be swamped by the approaching wave. As far as I could tell, no one had stuffed their cars or trucks with packing boxes and mattresses to move their worldly possessions to high ground. All they had transported were their vehicles and their pets. The mood of the crowd was neither festive nor somber. Everyone was simply waiting.

At ten o’clock the first sirens sounded. Thirty minutes later, I heard over a car radio that all coastal roads were closed. Police stood at barricades partway down the hillside to prevent anyone from entering the closed area. At eleven o’clock the sirens sounded a second time. That signaled that the first wave would arrive in 20 minutes.

Exactly at the predicted time, the entrance to Hilo Bay began to turn brown. Someone shouted, “It’s starting!”

The brown patch grew as seawater was pulled out of the bay, the force of the water kicking up silt from the bottom. A reef of black rocks, normally visible only during extreme low tide, appeared just off a popular picnic spot known as Coconut Island. It was the clearest sign that the water level in the bay was dropping. After 10 minutes, the rocks were covered again by seawater. A few more cycles, each lasting 20 to 30 minutes, the water level changing no more than a few feet, and the event was over. The city of Hilo had been spared.

Through it all, even as I was preparing to go to bed the previous night and, later, as I stood with my family and my neighbors and watched the water recede and recover, I kept thinking about those other people, thousands of miles away, somewhere along the coast of Chile. An unknown number of souls were trapped beneath the rubble of buildings that had collapsed during the earthquake. At that moment they were wondering whether they would ever be rescued.

Close Encounters

Grove Karl Gilbert, one of the first geologists to survey the American West and later acting director of the United States Geological Survey, once wrote,

It is the natural and legitimate ambition of a properly constituted geologist to see a glacier, witness an eruption, and feel an earthquake. The glacier is always ready, awaiting his visit; the eruption has a course to run, and alacrity only is needed to catch its more important phases; but the earthquake, unheralded and brief, may elude him through his entire lifetime.

Gilbert’s encounters with glaciers and volcanoes came easy. In 1899, while on a scientific expedition to Alaska, he spent months mapping, measuring and photographing nearly 40 glaciers. He had his encounter with active volcanoes when the expedition’s small ship came within sight of Pavlov volcano, which Gilbert later reported was steaming from a spot high on the peak, and then sailed close to Bogoslof Island, a mound of steaming crags that had risen recently from the sea. But the shaking of an earthquake kept eluding him.

He left Alaska a month too soon to feel the ground rock back and forth during a magnitude 7.4 earthquake near Yakutat Bay, which raised a 40-foot wave that washed the shoreline on which Gilbert had recently stood. Gilbert seemed genuinely disappointed to have missed it. Nearly 30 years earlier, he had been “tantalized,” so he wrote, when he left central California after an extended stay of several months and returned east just weeks before the Great Inyo Earthquake of 1872 shook the western half of the continent, from Oregon to Central America. His appointment with geological upheaval finally came on April 18, 1906. That morning, he was asleep at the Faculty Club at Berkeley—in town to attend a meeting about California mining and how it was ruining the environment—when, “by a tumult of motions and noises,” he was awakened and became aware “with unalloyed pleasure” that “a vigorous earthquake was in progress.”

The destruction in Berkeley was “trivial” by his estimation, but within two hours of the earthquake, he learned “that a great disaster had been wrought on the opposite side of the bay and that San Francisco was in flames.” It took him two days to find passage there by ferry.

When he arrived, the city was still burning. He chronicled the progress of the fire, watching as block after block of close-set wooden houses were consumed by flames. At one point, he recorded in his notebook the time it took for a two-story building to be destroyed: “roof gone in seven minutes; first falling of wall in nine minutes; flaming ruins in twelve minutes.” After the fire ended, he set off, again by ferry, to the area hardest hit by the earthquake, which was on the north side of the bay, and there he began a formal scientific investigation.

Gilbert would author a famous government report about the earthquake. At the end of the report, he considered the possibility that future earthquakes might strike San Francisco. Should a repeat of the 1906 event be expected within the lifetimes of the next few generations, he wondered, or had the recent calamity given the area long-term immunity from another violent disturbance? He had no answer. But he was sure that “timidity will cause some to remove from the shaken district and will deter others who were contemplating immigration.”

Hazard as an Occupation

Recently, I asked someone who was retiring after 30 years of studying earthquakes, which included a substantial tenure as head of the USGS Earthquake Hazards Program, whether he was disappointed that a major earthquake—on par with the 1906 event—had not happened on his watch. He answered no.

There was too much suffering after such events, he said. He had dealt with the aftermath of several significant quakes, including the 1989 Loma Prieta earthquake that, among other things, caused a span of the Bay Bridge that links San Francisco and Oakland to collapse. The official death toll from the earthquake was 57. Property loss was valued at $6 billion. As a result of the disaster, a new Bay Bridge is under construction. Planners hope it will be completed before the next big earthquake shakes the Bay area.

Understand that I am not wishing for destruction by natural forces, but I know that such events are inevitable. Also, I am no stranger to such catastrophes. I studied erupting volcanoes for 16 years. I have seen bodies cremated by passage of the hot hurricane-force wind known as nuée ardente. And I have stood on the hard surface of a recently congealed mudflow, knowing that thousands of people were entombed beneath my feet.

In January 2010, I watched, as millions of others did, with near disbelief as television cameras showed the destruction wrought in Haiti after an earthquake killed nearly a quarter million people and left the capital city, Port-au-Prince, in ruins. A month later, the earthquake in Chile, which was a thousand times stronger than the 1989 Loma Prieta earthquake, collapsed multistoried buildings in Concepión, the second largest city in the country. And during the spring months, I followed, as many did, the progress of repeated ash clouds erupted from an Icelandic volcano, the clouds wreaking havoc on international air travel and crippling world commerce.

And so I share the humanist view and feeling of my seismological friend. But, like Grove Karl Gilbert, I am drawn to experiencing great geologic forces, wanting to be present when they are unleashed. It should come as no surprise that, like Gilbert, I hope to experience the shaking of a major earthquake. I am quite sure others harbor a similar, secret wish.

Disaster Psychology

Years ago, during an informal discussion about earthquakes and how they should be studied, I commented to colleagues that instead of adding yet another seismologist or geologist or geodesist to the group, adding a psychologist would make more sense. One of the major goals of the Earthquake Hazards Program is to keep the public informed about the perils associated with such events. It seemed to me imperative that we, as scientists, understand how the public will react to the sort of information we might be called upon to provide—potentially terrifying information about imminent cataclysms. My suggestion was met with blank stares.

I have also suggested that once the prediction of earthquakes becomes commonplace—and I think it is inevitable that, someday, earthquake prediction will be on par with forecasting the path and strength of hurricanes, if not rising to the certainty of predicting the tides—that contingency plans will have to be made for the crowds that will assemble in the forecasted epicentral area to feel the ground shake.

Bear with me on this. I had an experience years ago that is pertinent to this question.

It happened on the Nevada desert back in the days when underground nuclear tests were still conducted. Whenever such a test was scheduled, an army of graduate students was sent out across the desert to station ourselves at regular intervals along a line that ran radially away from the blast. (The point of the exercise was to study the structure of the Earth’s crust.) Each of us was equipped with a portable seismograph to record the precise time the initial ground shaking arrived from the blast. For one test, I was lucky and drew the lot that put me second closest to the detonation.

I arrived at my assigned position early in the morning. I knew the exact second when the ground would start to vibrate. And I knew the direction the wave would come from. With five minutes to go, I made sure I was standing on firm ground and facing in that direction.

A minute before the wave was scheduled to arrive, I remember feeling a surge of adrenaline rush through my body. Then, with a moment to go, I saw the ground rippling on the distant horizon. In less than a breath, the wave had passed under me. I could distinctly feel the pulses running up my legs and through my body. The whole experience lasted barely a second. I turned after the wave passed me and watched it disappear over the other horizon.

In the vernacular of my generation, it was better than an E ticket at Disneyland.

From that experience, I feel justified in predicting that there will be professional and amateur earthquake chasers. Droves of people will flock to any area that is predicted to have a major earthquake, arriving by whatever means required to be there at the appointed time. It will be much as it is today when crowds of people gather along the strip of land that the moon’s shadow follows during a total solar eclipse. Travel agencies will book tours to “Ride the Earth’s Crust.” Hawkers will sell T-shirts and commemorative plates.

From a different perspective, people who already live in seismic zones will be better prepared than any group before them for the strong shaking that is about to come.

Such a world is in the future. How far ahead, I do not know. In the meantime, I struggle with the dilemma of the “properly constituted geologist.” I desperately want more experience of the great forces of nature. I want to hear the acoustically epic roar of the rupturing crust, of the ocean emptying from its basin and then returning. Yet I cannot sincerely wish for it, because I know, as perhaps only geologists and the victims of natural cataclysms do, how much human suffering is mixed in with the flows and ejections of nature in its most violent moments.

 

EMAIL TO A FRIEND :


Bottom Banner