An immense submarine earthquake registering 9.3 on the Richter scale sent a tsunami ripping across the Indian Ocean this past December, ravaging coastal communities from Thailand to Sri Lanka to Eastern Africa. It was one of the most serious natural disasters of modern times—the death toll approached 300,000, with an estimated 800,000 people left homeless. As disease, famine, and damaged national infrastructures continue to plague the devastated countries, the tsunami's repercussions will undoubtedly be felt for years to come.

Over the years, The Atlantic has published the work of several writers for whom Earth's violent outbursts have invited description—and investigation. These phenomena are often tragic, but utterly extraordinary, reminding us of our smallness and conjuring dreams of gods and giants. At the same time, such catastrophic events provoke contemplation of the tenuous relationship between the Earth and human communities. How do we understand what happens in the natural world and confront our own fragility in the face of it?

The eruption of Krakatoa in 1883 is considered the moment when the Earth's capacity for violence first exploded into modern consciousness. News of the environmental and humanitarian consequences of this disaster traveled quickly around the world. In the September 1884 Atlantic, E. W. Sturdy chronicled the event from the volcano's earliest rumblings—felt as a "subterranean disturbance" by the inhabitants of Batavia in May—through the eruption itself in August. The volcano demolished its island home, Rakata, an Indonesian island located in the Sunda Strait. Tens of thousands of people were killed by the falling volcanic ash and fumes and by the rash of tsunamis that ensued. The violent display was perplexing and frightening for those who witnessed it—especially given the limits of geological understanding at the time:

On the afternoon of the 26th there were violent explosions at Krakatoa, which were heard as far as Batavia. High waves first retreated, and then rolled upon both sides of the strait. During a night of pithy darkness these horrors continued with increasing violence, augmented at midnight by electrical phenomena on a terrifying scale, which not only enveloped the ships in the vicinity, but embraced those at a distance of ten to twelve miles. The lurid gleam that played on the gigantic column of smoke and ashes was seen in Batavia, eighty miles away. Some of the debris fell as fine ashes in Cheibon, five hundred miles to the eastward.

Sturdy quoted at length from the testimony of Captain Watson of the British ship Charles Bal, who was sailing nearby during the month of August and was caught in a terrific downpour of volcanic debris:

The ship from truck to water-line was as if cemented; spars, sails, blocks, and ropes were in a horrible state; but, thank God, no one was hurt, nor was the ship damaged. But think of Anjer, Merak, and other little villages on the Java coast!

Thousands of years before Krakatoa, another island volcano devastated the communities in and around the Aegean Sea. In "The Promise of Thera: A Bronze Age Pompeii" (December 1967 Atlantic), Emily Vermeule, a professor of art and Greek, described what the event must have been like:

After long discharges of ash, in about 23,000 B.C. and 1500 B.C. it seems that the normal volcanic outlets became plugged, and super-hot gas-charged magma burst up from under the earth through a solid cap of island, throwing huge boulders fifty kilometers in the air and scattering hot ash, or tephra, over the whole eastern Mediterranean. When the magma chamber under the earth drained out, the remaining pillars of matter were too fragile to stand, and everything collapsed into the new hollow with a huge inrush of sea. This invasion of water was accompanied by a trembling of the earth, incredible noise, 150-foot tidal waves, electrified atmosphere, gales, steam, sulfuric mist, and showers of ash which barred the sunlight and turned much of the world dark. In 1500 B.C., when the Mediterranean was densely inhabited by highly civilized people, the eruption of Thera must have caused a shocking amount of physical damage and mental agony on all the neighboring coasts.

For years, many had speculated that the buried community at Thera, on the present-day island of Santorini, might be the historical basis for Plato's myth of the Lost Atlantis—Poseidon's maritime city cast into the sea by Zeus as punishment for its worldly excesses. Vermeule recounted the long history of efforts to excavate the site, suggesting that much of the interest in and funding for the project over the years had been inspired by the Atlantis story:

Plato had written too well. His vague, fragmentary tale of an earthly paradise sunk beneath the waves, from which we are barred forever, has been a siren call to navigators of the ocean and of the spirit for 2400 years. Atlantis has been found many times and always lost again. It is an indestructible, necessary daydream.

In the nineteenth century, two young French scholars, Henri Mamet and Henri Gorceix, had gone in search of the lost city, but at the time the Therasian site was thought too dangerous for excavation. It wasn't until the mid-twentieth century that scholars—Vermeule among them—were able to tunnel into the earth in search of the preserved artifacts of the island's ancient denizens.

The volcano was still active at the time Vermeule was writing, and remains so today. There had been several eruptions in the early part of the twentieth century and the little island continued to tremble from frequent earthquakes. A faction of residents had left in fear in the fifties, but of the large number who stayed on, Vermeule wrote,

It would be interesting to explore their deeper thoughts about life on a volcano, and to assess the quality of their childhood terrors. Yet Greeks are full of courage and disconcerting honesty; they are used to the threats of nature. From day to day they are more concerned with poverty than with forces under the earth.

Fourteen years later, James Fallows's investigation of the threat of a major earthquake in southern California, "Living On the Fault Line," appeared in the October 1981 Atlantic. In the desert of the San Bernardino Valley, it was not poverty or a spirit of bravery that kept communities burgeoning in a high-risk location. As Fallows explained,

People have moved to this valley seeking cheaper real estate, the good life in the sun, and the opportunities that economic growth creates. They are an hour's drive from the mountains, an hour from the ocean, and far, far away from such northern, urban cares as frost and economic decline. And their search has led them to the area that, according to many scientists, will be the site of the next catastrophic earthquake to strike the continental United States.

For California communities the possibility of a devastating earthquake was almost beyond the scope of the imagination, in part because residents were too comfortable with minor quakes. The last great quake had been in San Francisco in 1906. There had been other major earthquakes throughout the world since then, but these events, Fallows suggested, were all too quickly forgotten. "Within a matter of years," he wrote, "there will be no one alive in California with a personal memory of the effects of a 'great' quake there."

The task had thus fallen to geologists to not only seek out a scientific understanding of these phenomena, but also to find ways to convey the extent of the danger in a manner useful to the layperson. The Richter scale, Fallows explained, is used to quantify the size of an earthquake. The Mercalli scale, however, attempts to qualify the magnitude of the disturbance in terms of damage done to such human-built structures as buildings and highway overpasses. But an eloquent allusion to the potential for a humanitarian disaster is perhaps most alarming. After doing a series of calculations based on the possibility of a "great" quake, the Federal Emergency Management Agency reported,

Because of the large concentration of population and industry, the impacts of such an earthquake would surpass those of any natural disaster thus far experienced by the Nation. Indeed, the United States has not suffered any disaster of this magnitude on its own territory since the Civil War.

Even assuming certain knowledge of the probability of a great quake and an estimation of the sort of damage it could do, how does a community, a state, a nation prepare? The challenge, Fallows suggested, is to minimize the danger by strengthening buildings and infrastructure ahead of time, and working out in advance what will need to be done in the event of a disaster. Unfortunately, such preparations are often thwarted by political and social complications:

Most of the public bodies that have wrestled with the earthquake problem seem to have proven more successful so far in accommodating their own professional and bureaucratic habits than in doing things that would make a significant difference if a great earthquake should strike, say, next month.

In "The Liquid Earth" (January 1999 Atlantic), Brenda Bell recounted the chilling story of the Herren family, who built their home at the base of a cliff on Bainbridge Island, Washington. In the early morning hours of January 19, 1997, asleep in their beds, the family was smothered by a landslide and swept to sea. These deadly slides represent a quiet, swift, and disturbingly frequent type of natural disaster. They often accompany large-scale earthquakes in the ocean or on land, but at times no more than a heavy rainfall can set a narrow band of mud sliding. As Bell wrote, "Landslides are perhaps the most widespread geologic hazard, and, since they are a function of gravity, an intractable one."

Although it is still extremely difficult for scientists to predict exactly when a landslide will occur, it is not hard to identify where one is likely to take place. Many homeowners who are in the path of danger, however, are stubbornly oblivious. "Debris flows are widely seen as cosmological misfires, freaks of nature," Bell wrote, "and as a result people tend to underestimate the risks they pose." For a while, however, the residents of Bainbridge Island were traumatized by the tragic death of the Herren family:

At first people had disturbing dreams—dreams of mud. They awoke at night to the malevolent sound of rain. With newly critical eyes they examined the waterfront houses of strangers. How close was the house to the cliff? Were the trees leaning? What caused those suspicious bare spots? For a time, envy abated.

Bell warned that these muddy nightmares would fade too soon and that people would once again lose reverence for the violent strength of the Earth. Accounts of natural disaster, tales that should serve as warnings, are too quickly dismissed as the stuff of myth:

Memories are short. Events have proved that. As long as houses remain on the beach, as long as the views beckon, people will be tempted to push their luck. There could come a day—not soon, but someday—when the worry here is forgotten, when parents and their children sleep peacefully again in their brave houses by the water.

Kathryn Crim