The Environmental Catastrophe that Remade History

by Gar Smith

"In AD 535-536, [humankind] was hit by one of the greatest natural disasters ever to occur. It blotted out much of the light and heat of the sun for 18 months and the climate of the entire planet began to spin out of control." - David Keys, Catastrophe (Ballentine Books, 1999)

In an extraordinary new book, British historian David Keys convincingly traces many disparate threads of modern history back to a single (and quite literally Earth-shaking) event - the explosion of a "supervolcano" in the third decade of the sixth century.

The explosion tore through the same South Pacific region that later gave rise to the Krakatoa eruption in 1883. The earlier convulsive detonation created the islands of Sumatra and Java and left behind a gap that is now known as the Sunda Straits.

The eruption's aftermath was felt worldwide "Crops failed in Asia and the Middle East as global weather patterns radically altered. Bubonic plague, exploding out of Africa [as the climate change increased rodent populations], wiped out entire populations in Europe. Flood and drought brought ancient cultures to the brink of collapse. In a matter of decades, the old order died and a new world - essentially the modern world as we know it today - began to emerge."

The 100 years following the eruption marked the beginning of the Dark Ages. During the cold years that enveloped the ash-clouded Earth, the Roman Empire began to collapse. Yellow dust fell like snow over the dying croplands of Asia. A 32-year drought clutched at the throat of Central America, prompting a popular uprising that toppled the great pyramid-building empire of the Aztecs.

The evidence has been there all along, waiting for someone to piece it together. Over a period of four years, Keys did just that. Keys visited more than 1,000 archeological sites in 60 countries and he discovered clues everywhere - buried in the rings of trees, hidden in polar ice cores, and lost in the forgotten jottings of ancient scribes.

In the cellulose records encoded in the tree trunks of the world's forests, Keys discovered that a sudden, calamitous chill in the mid-Sixth Century had stunted tree growth everywhere on Earth.

Ice cores drilled deep into the frozen Arctic turned up the black signature of volcanic ash. Ice cores sunk into the icepacks of Antarctica turned up the same long-buried traces.

In the year 535 CE, the journals of the Roman historian Procopius recorded "a most dread portent ... [T]he sun gave forth its light without brightness like the moon during this whole year." From that day on, Procopius wrote, "men were not free from war, nor pestilence, nor anything leading to death."

In Japan, an Imperial edict lamented that "yellow gold and ten thousand strings of cash cannot cure hunger ... [when a country is] starving of cold."

In China, Keys found an entry in the ancient History of the Southern Dynasties that referred to a great explosion that rocked the world in February 535 when "there twice was the sound of thunder."

Finally, in an obscure Indonesian chronicle, the Pustaka Raja Purwa (The Book of Ancient Kings), Keys found this chilling passage:

"[A] great glaring fire, which reached to the sky came out of the mountain ... There was a furious shaking of the earth, total darkness, thunder and lightning. Then came forth a furious gale, together with torrential rain, and a deadly storm darkened the entire world ... [W]hen the waters subsided, it could be seen that the island of Java had been split in two, thus creating the island of Sumatra."

Keys reasons that the 535 eruption was "one of the largest volcanic events of the past 50,000 years." His reconstruction of the event paints a hellish vision of "molten magma [shooting] into the air at up to 1,500 miles per hour, reaching heights of perhaps 30 miles. The sound of this explosion would have broken the eardrums of most humans and animals living within a 15-mile radius ... [After the blast] car-sized chunks of the mountain ... would have fallen back to earth within a radius of three to seven miles. The microfragments, however, would have been carried skyward by powerful convection currents.

"A hot, poisonous wall of destruction, more than 1,000-feet high, would have moved outward ... at up to 250 mile per hour, killing anything in its path," Keys theorizes. A mushroom cloud ascending from the 1,650-degree-Fahrenheit heart of the volcano would have rained ash on villages and forests a thousand miles distant, while a six-foot-deep blanket of floating pumice would have coated the seas.

Keys believes that the eruption, and the climatic destablization that followed, "resynchronized world history."

Supervolcanoes Today
What happened in 535 will eventually happen again - and it could happen in North America. "Brooding an estimated six miles beneath the scenic wonderland of America's Yellowstone National Park is a vast liquid time bomb the size of Lake Michigan," Keys writes. "Yellowstone is host to the world's largest dormant volcano,- a huge caldera covering around 1500 square miles."

On February 3, BBC World News called the Yellowstone supervolcano "overdue" for an explosion. "Yellowstone has gone off roughly once every 600,000 years," the BBC reported. "Its last eruption was 640,000 years ago." Prof. Bill McGuire, a hazards research specialist at London's University College told the BBC that rising ground surfaces indicate that the Yellowstone caldera is "still active and on the move."

Ted Nield of the Geological Society of London compares the eruption of a supervolcano to the Earth being hit by a large asteroid. "It's just like a nuclear winter," Nield said. "The effects could last four or five years, with crops failing and the whole ecosystem breaking down." But, while it is conceivable that nuclear-tipped rockets could deflect an approaching space-rock, "there is nothing at all you can do about a supervolcano."

Keys lists eight other supervolcanoes that are displaying "ominous signs of increasing restlessness." They are located beneath Long Valley, California, below fields west of Naples, Italy, within the Rabaul volcano in Papua New Guinea, in Mexico and at several locations within Alaska's Aleutian Islands.

"If any of them [were] to explode," Keys writes, "world climate would be plunged into chaos, precisely as it was in the sixth century. But with world population at 40 times its sixth-century level, the death toll would almost certainly run into the hundreds of millions."

Keys' conclusion is a sobering one. "In doing the research for this book," he writes, "I have developed a greatly increased respect for the forces of nature and their power to change history."

A two-hour documentary based on Keys' findings will air on PBS stations in mid-May as part of a series called Secrets of the Dead, produced by WNET [450 West 33rd St., New York, NY 10001, (212) 560-1313, www.thirteen.org].