of the volcanic cones) collapsed and disappeared. This in turn generated tsunamis, with some waves coming ashore at heights of 130 feet. The destruction resulted in tens of thousands of deaths in the region.

In his book Krakatoa, Simon Winchester records that months later huge pieces of pumice thrown out by the eruption, some weighing several tons, drifted as far as the coastline of Africa at Zanzibar, about 4,000 miles away. Welded to the boulders' upper surfaces were the macabre remains of dozens of human skeletons, together with the bones of animals such as monkeys and tigers that had been killed by the blast.

However, as calamitous as these events were, they seem benign and almost insignificant when compared with the geologic events that over millions of years

Most of the time, the planet we live on seems like a safe and stable place. But as recent events have proven, colossal forces determined by the physics of the earth slowly build up to be suddenly released in catastrophic earthquakes, volcanoes and tsunamis that spawn yet more science and environment concerns for many inhabitants.

Vision was in the process of preparing an article on this subject when the Asian tsunami struck on December 26, 2004, with the catastrophic results we all know too well. Before a horrified worldwide TV audience, the Indian Ocean basin reeled following the massive earthquake and resultant tsunami, which together may have obliterated as many as 300,000 lives. All of us were forcibly reminded that Earth--and all of us along with it--is in fact quite vulnerable.

Bill McGuire, a volcanologist and professor of geophysical hazards at University College, London, expresses it this way: "The Earth is an extraordinarily fragile place that is fraught with danger: a tiny rock hurtling through space, wracked by violent movements of its crust and subject to dramatic climatic changes as its geophysical and orbital circumstances vary" (A Guide to the End of the World, 2002 ).

Each week approximately 10,000 detectable earthquakes shake our planet. About 2,000 of them can be felt, and on average, two of them cause damage. In addition, around 20 volcanoes are erupting at any given moment. Those who find themselves in the way of such traumatic events often wonder whether God is punishing them or whether the world is coming to a cataclysmic end.

ALL SHOOK UP

Earthquakes and volcanoes are probably the most spectacular of all natural disasters.

It is a fact that earthquakes and their aftereffects have caused multiple millions of deaths over the course of human history. In terms of loss of life, one of the most catastrophic was the one that struck China in 1556, killing an estimated 830,000 people. And one of the most devastating in modern times struck Japan on September 1, 1923, registering 7.9 on the Richter scale. The quake, which shook Tokyo, Yokohama and the surrounding area, was followed by a tsunami, numerous landslides, and devastating fires. Within two days at least 140,000 people had died and the two cities lay largely in ashes.

With regard to volcanoes, nearly everyone is familiar with one of the most famous events in history--the 1883 explosions of Indonesia's Krakatau (or Krakatoa), an island consisting of three volcanic cones between the islands of Java and Sumatra. Volcanic activity began in May and continued through August. Pressure built up inside the cones because gas escaping from the magma had no outlet, and like a steam boiler with its safety valve closed, they exploded with a series of powerful blasts on August 26 and 27. Four great explosions over the course of a few short hours hurled rocks into the air, some of which showered down on nearby ships. Inhabitants of the Indian Ocean island of Rodriguez, 3,000 miles away, reported hearing the noise. The force was so great that the northern half of the island (including two of the volcanic cones) collapsed and disappeared. This in turn generated tsunamis, with some waves coming ashore at heights of 130 feet. The destruction resulted in tens of thousands of deaths in the region.

In his book Krakatoa, Simon Winchester records that months later huge pieces of pumice thrown out by the eruption, some weighing several tons, drifted as far as the coastline of Africa at Zanzibar, about 4,000 miles away. Welded to the boulders' upper surfaces were the macabre remains of dozens of human skeletons, together with the bones of animals such as monkeys and tigers that had been killed by the blast.

However, as calamitous as these events were, they seem benign and almost insignificant when compared with the geologic events that over millions of years

uite vulnerable.

Bill McGuire, a volcanologist and professor of geophysical hazards at University College, London, expresses it this way: "The Earth is an extraordinarily fragile place that is fraught with danger: a tiny rock hurtling through space, wracked by violent movements of its crust and subject to dramatic climatic changes as its geophysical and orbital circumstances vary" (A Guide to the End of the World, 2002 ).

Each week approximately 10,000 detectable earthquakes shake our planet. About 2,000 of them can be felt, and on average, two of them cause damage. In addition, around 20 volcanoes are erupting at any given moment. Those who find themselves in the way of such traumatic events often wonder whether God is punishing them or whether the world is coming to a cataclysmic end.

ALL SHOOK UP

Earthquakes and volcanoes are probably the most spectacular of all natural disasters.

It is a fact that earthquakes and their aftereffects have caused multiple millions of deaths over the course of human history. In terms of loss of life, one of the most catastrophic was the one that struck China in 1556, killing an estimated 830,000 people. And one of the most devastating in modern times struck Japan on September 1, 1923, registering 7.9 on the Richter scale. The quake, which shook Tokyo, Yokohama and the surrounding area, was followed by a tsunami, numerous landslides, and devastating fires. Within two days at least 140,000 people had died and the two cities lay largely in ashes.

With regard to volcanoes, nearly everyone is familiar with one of the most famous events in history--the 1883 explosions of Indonesia's Krakatau (or Krakatoa), an island consisting of three volcanic cones between the islands of Java and Sumatra. Volcanic activity began in May and continued through August. Pressure built up inside the cones because gas escaping from the magma had no outlet, and like a steam boiler with its safety valve closed, they exploded with a series of powerful blasts on August 26 and 27. Four great explosions over the course of a few short hours hurled rocks into the air, some of which showered down on nearby ships. Inhabitants of the Indian Ocean island of Rodriguez, 3,000 miles away, reported hearing the noise. The force was so great that the northern half of the island (including two of the volcanic cones) collapsed and disappeared. This in turn generated tsunamis, with some waves coming ashore at heights of 130 feet. The destruction resulted in tens of thousands of deaths in the region.

In his book Krakatoa, Simon Winchester records that months later huge pieces of pumice thrown out by the eruption, some weighing several tons, drifted as far as the coastline of Africa at Zanzibar, about 4,000 miles away. Welded to the boulders' upper surfaces were the macabre remains of dozens of human skeletons, together with the bones of animals such as monkeys and tigers that had been killed by the blast.

However, as calamitous as these events were, they seem benign and almost insignificant when compared with the geologic events that over millions of years

g to a cataclysmic end.

ALL SHOOK UP

Earthquakes and volcanoes are probably the most spectacular of all natural disasters.

It is a fact that earthquakes and their aftereffects have caused multiple millions of deaths over the course of human history. In terms of loss of life, one of the most catastrophic was the one that struck China in 1556, killing an estimated 830,000 people. And one of the most devastating in modern times struck Japan on September 1, 1923, registering 7.9 on the Richter scale. The quake, which shook Tokyo, Yokohama and the surrounding area, was followed by a tsunami, numerous landslides, and devastating fires. Within two days at least 140,000 people had died and the two cities lay largely in ashes.

With regard to volcanoes, nearly everyone is familiar with one of the most famous events in history--the 1883 explosions of Indonesia's Krakatau (or Krakatoa), an island consisting of three volcanic cones between the islands of Java and Sumatra. Volcanic activity began in May and continued through August. Pressure built up inside the cones because gas escaping from the magma had no outlet, and like a steam boiler with its safety valve closed, they exploded with a series of powerful blasts on August 26 and 27. Four great explosions over the course of a few short hours hurled rocks into the air, some of which showered down on nearby ships. Inhabitants of the Indian Ocean island of Rodriguez, 3,000 miles away, reported hearing the noise. The force was so great that the northern half of the island (including two of the volcanic cones) collapsed and disappeared. This in turn generated tsunamis, with some waves coming ashore at heights of 130 feet. The destruction resulted in tens of thousands of deaths in the region.

In his book Krakatoa, Simon Winchester records that months later huge pieces of pumice thrown out by the eruption, some weighing several tons, drifted as far as the coastline of Africa at Zanzibar, about 4,000 miles away. Welded to the boulders' upper surfaces were the macabre remains of dozens of human skeletons, together with the bones of animals such as monkeys and tigers that had been killed by the blast.

However, as calamitous as these events were, they seem benign and almost insignificant when compared with the geologic events that over millions of years

veryone is familiar with one of the most famous events in history--the 1883 explosions of Indonesia's Krakatau (or Krakatoa), an island consisting of three volcanic cones between the islands of Java and Sumatra. Volcanic activity began in May and continued through August. Pressure built up inside the cones because gas escaping from the magma had no outlet, and like a steam boiler with its safety valve closed, they exploded with a series of powerful blasts on August 26 and 27. Four great explosions over the course of a few short hours hurled rocks into the air, some of which showered down on nearby ships. Inhabitants of the Indian Ocean island of Rodriguez, 3,000 miles away, reported hearing the noise. The force was so great that the northern half of the island (including two of the volcanic cones) collapsed and disappeared. This in turn generated tsunamis, with some waves coming ashore at heights of 130 feet. The destruction resulted in tens of thousands of deaths in the region.

In his book Krakatoa, Simon Winchester records that months later huge pieces of pumice thrown out by the eruption, some weighing several tons, drifted as far as the coastline of Africa at Zanzibar, about 4,000 miles away. Welded to the boulders' upper surfaces were the macabre remains of dozens of human skeletons, together with the bones of animals such as monkeys and tigers that had been killed by the blast.

However, as calamitous as these events were, they seem benign and almost insignificant when compared with the geologic events that over millions of years

of the volcanic cones) collapsed and disappeared. This in turn generated tsunamis, with some waves coming ashore at heights of 130 feet. The destruction resulted in tens of thousands of deaths in the region.

In his book Krakatoa, Simon Winchester records that months later huge pieces of pumice thrown out by the eruption, some weighing several tons, drifted as far as the coastline of Africa at Zanzibar, about 4,000 miles away. Welded to the boulders' upper surfaces were the macabre remains of dozens of human skeletons, together with the bones of animals such as monkeys and tigers that had been killed by the blast.

However, as calamitous as these events were, they seem benign and almost insignificant when compared with the geologic events that over millions of years formed the earth as we know it. Over the past 50 years, remarkable advances have been made in understanding the nature of the earth and the forces and events that formed it. They include the eruption of supervolcanoes and cataclysmic earthquakes, global plate tectonics, the Pacific "ring of fire," the formation of ocean floors, and the formation and movement of continents.

The good news is that according to the geological record, such events develop over a vast expanse of time. The bad news is that in some places, another catastrophic event may be overdue.

TROUBLE BREWING

One example is the caldera under Yellowstone National Park. In the prehistoric past, the area was the site of three great eruptions: one of these spewed out more than 600 cubic miles of solid material. The amount of magma expelled caused the roof of the chamber under Yellowstone to collapse, forming a one-thousand-square-mile caldera. A second series of eruptions freed about 70 cubic miles of magma, which resulted in the 17-mile-wide Island Park caldera. A third cycle of eruptions is thought to have dropped ash over much of North America and to have formed the 30-by-50-mile Yellowstone caldera.

Eruptions have occurred in the Yellowstone area about every 600,000 years. But the last one was probably 640,000 years ago, so some say the next one is overdue. According to the U.S. Geological Survey, the three caldera-forming eruptions were, respectively, about 2,500, 280 and 1,000 times larger than the May 18, 1980, eruption of Mt. St. Helens in the state of Washington. "Together," says the USGS, "the three catastrophic eruptions expelled enough ash and lava to fill the Grand Canyon."

According to experts, the science behind another possible Yellowstone eruption is reliable; only the timing is uncertain. The BBC, in conjunction with other sponsors, recently aired a ?2.8 million TV docudrama that highlights the potential global fallout from a Yellowstone supervolcanic eruption.

ATLANTIC TSUNAMI?

Although there is disagreement among scientists about the significance of the threat, another disaster waiting to happen could be the Cumbre Vieja volcano on the Canary Island of La Palma.

A number of American and British scientists have been watching a chunk of volcanic rock on the west side of the peak, which cracked and slipped during its 1949 eruption. Larger than the Isle of Man, the massive rock is gradually slipping further and is poised to crash into the sea. A new eruption would likely trigger the event. When this may occur is uncertain, however. No one knows whether it will be in 10 years or in 10,000 years.

Geological hazards specialist McGuire comments: "What is certain is that at some point in the future the west flank of the Cumbre Vieja on La Palma will collapse, and the resulting tsunamis will ravage the entire Atlantic rim."

He adds that "Steven Ward of the University of California at Santa Cruz and Simon Day of University College London's Benfield Greig Hazard Research Centre created quite a stir recently when they published a scientific paper that modelled th