by David Keys
When Long Valley last erupted, it produced 125 cubic miles of magma and generated a pyroclastic flow of such vast proportions that when the wave settled it added 350 feet to the surface height over several hundred square miles.
Half a world away in Europe, another vast caldera is beginning to flex its volcanic muscles. Just three miles beneath the western suburbs of Naples is a huge magma reservoir containing between 70 and 250 cubic miles of molten rock. Since 1969 pressure from this magma has caused land to rise and fall twice—by about six feet. In the early 1980s it generated up to three hundred small earthquakes per week (each up to 4.2 on the Richter scale). There is no doubt that this caldera, known as the Campanian/Campi Flegrei complex, is becoming increasingly restless.
So far, it is known to have erupted cataclysmically twice—once thirty-seven thousand years ago, when it ejected 20 cubic miles of magma, and once twelve thousand years ago, in an explosion about a sixth of the size of the earlier one. In the first eruption the pyroclastic flow—the wave of superheated dust and gas surging along the ground—was so deep that it engulfed three-thousand-foot-high ridges thirty-five miles away.
The Campanian/Campi Flegrei caldera complex¹ is about 150 times as large as the crater area of the more famous nearby volcano of Vesuvius, which in A.D. 79 produced less than half a cubic mile of magma when it erupted. Again, no one knows when the Italian caldera will explode again on a truly massive scale but, like Yellowstone and Long Valley, it is virtually certain to do so one day—perhaps, in this European example, sooner rather than later.²
The fourth major volcanic caldera currently displaying ominous signs of increasing restlessness is that of Rabaul in Papua New Guinea. Since 1910 the number of minor eruptions appears to have increased (it may simply be that records have been better kept this century than last). Minor eruptions and earthquakes have occurred in twenty-two of the past ninety years, compared to only two recorded in the previous ninety years. What’s more, earthquakes also seem to have increased—there have been up to thirteen thousand tremors per year since the early 1980s. Rabaul is known to have erupted cataclysmically twice so far—3,500 and 1,250 years ago.³ In the later eruption, the 48-square-mile crater produced about 2.4 cubic miles of magma.
Along with these four, there are five other large and potentially active caldera volcanoes in the Alaskan Aleutian Islands and Mexico. These nine restless craters represent a significant threat to the world’s future economic and political well-being. If any one of them was to explode, world climate would be plunged into chaos, precisely as it was in the sixth century. But with world population at forty times its sixth-century level, the death toll would almost certainly run into the hundreds of millions. And just as history was resynchronized fourteen and a half centuries ago, a future caldera eruption, through its climatic impact, would almost certainly destabilize the economic and geopolitical status quo, leading to a second resynchronization of history.
Tracking down what really happened in the distant past is difficult enough, but working out what might happen in the future is even more of a challenge. Nevertheless, the two tasks are integrally linked. Futurology, that most problematic of disciplines, relies almost entirely on learning from the past in order to predict the future—or at least to offer options as to what might happen.
Given the experience of the sixth-century eruption and its consequences, yet taking into account the more integrated nature of the modern world, I believe that a similar catastrophe today would ultimately shift the balance of geopolitical power away from the West and in favor of the Third World.
Any major nontropical Northern Hemisphere eruption would disrupt climate throughout North America, Eurasia, and Africa. An eruption of the caldera of Rabaul would almost certainly also affect climate in South America and Australia, as it would distort the wind circulation and ocean current systems in both the Northern and Southern Hemispheres.
In the Third World, the dust, sulfuric acid aerosols, and ice-crystal clouds spewed into the air would possibly lead to drought and massive crop failure—exactly as it did in the sixth century. China, India, Africa, and (depending on the latitude of the eruption) Brazil would be hit hardest. Outside the Third World, Russia would also be very badly affected. Historically, these areas have always been the most vulnerable to famine. Indeed, on a number of occasions, natural oscillations in world climate have produced multiregion crop failures without volcanic factors playing any part at all.
The last such catastrophe—largely ignored by the history books—was back in 1876–1878, when fifteen to twenty million people died in droughts in north China, central India, Morocco, and northeast Brazil. In China nine and a half million people perished in four provinces. In the worst hit, Shanxi, just over a third of the population (six million out of fifteen million) died, while the death tolls in the other three provinces (Zhieli, Henan, and Shandong) were two and a half million, one million, and half a million, respectively. So desperate was the situation that many had to resort to cannibalism or eating the thatch from the roofs of their houses to survive. To avoid death by starvation, destitute farmers had to sell their daughters into prostitution and their sons into slavery.
At the same time, at least five million died in India, with particularly severe suffering in the provinces of Madras, Bombay, and Mysore. In the Madras region alone three and a half million people died from starvation and cholera. The cities were packed with refugees from the drought-stricken countryside. In Bombay, quite apart from cholera, tens of thousands of the inhabitants—weakened by lack of food—died in a devastating smallpox epidemic.
Farther west, in the northern half of Africa, Morocco and Ethiopia were also hit by famine, while in South America, half a million people died in northeast Brazil in a catastrophic drought. Up to 50 percent of the population was killed in some areas.
A similar multiregional famine also struck in 1789–1792 and seems to have contributed to the French Revolution. In those years, crops failed in France, the northern United States, northeast Brazil, and most appallingly in India, where the resultant mass starvation—known as the “Skull Famine”—caused so many deaths that it was impossible to keep count of the bodies. Bombay, Hyderabad, Gujarat, Orissa, and North Madras were devastated.
In neither the 1790s nor the 1870s catastrophe was there any volcanic causation—and it must be noted that these disasters were on nothing like the scale of the mid-sixth-century holocaust, which was proportionately volcanically triggered. Nevertheless, the eighteenth- and nineteenth-century disruptions do vividly illustrate precisely which areas of the globe would be most vulnerable to a modern-day volcanically induced famine.
A major caldera eruption could quite easily disrupt climate to such an extent that hundreds of millions of people would die. If by some awful coincidence the event struck at the same time as a natural downturn (such as occurred in the 1790s and 1870s), the death toll from starvation and associated epidemics could well top a billion, or even two billion.
In a virtually planetwide disaster of this scale, political administration would rapidly disintegrate in many areas. Banditry would increase, huge refugee flows would develop, epidemics would break out, and the medical infrastructure would be totally overwhelmed. Cholera, measles, typhus, and dysentery epidemics would occur on a massive scale. And, as in the sixth century, it is even conceivable that bubonic plague could again devastate substantial areas.
Contrary to popular belief, plague is still alive and well in a number of locations on four continents. Over the past ten years at least twenty thousand individuals have contracted the disease. Four thousand have actually died from it in such places as Peru, Vietnam, China, India, southern Africa, and Madagascar.
Millions of wild rodents in central Asia, southwest China, East Africa, the central Andes, the western United States, Brazil, and central India still carry the plague bacillus. Climatic chaos could still lead to the disease breaking out of its wild-rodent reservoir into the human world on a substantial scal
e in Asia, Africa, and South America if the medical infrastructure collapsed there.
Refugee flows would serve to further spread disease and provoke conflict. In many areas, refugees would be seen by local populations as competition for scarce resources and might well be slaughtered in substantial numbers. Although most refugee flows would be within the Third World itself, some would also penetrate the First World.
Mexican refugee pressure on the mile-long U.S. frontier would almost certainly be beyond the U.S. government’s ability to contain. Even now, in totally normal climatic circumstances, undetected illegal economic migration from Mexico totals an estimated 230,000 individuals per year.4 And the Mediterranean would almost certainly prove no obstacle to desperate groups of refugees seeking to enter Europe from northern Africa.
While much of the Third World would be suffering from famine, epidemics, and administrative collapse, western Europe, the United States, and Canada would suffer from massive food shortages—but probably not from starvation. The West’s higher-yield crops and more sophisticated and entrenched governmental machines and transport systems would almost certainly ensure that absolutely basic food needs were met and that emergency measures were introduced to ensure proper allocation and distribution. Rationing would no doubt have to be in force for several years.
Of course, wherever the eruption took place, substantial numbers of people would die as a direct result of the explosion and subsequent devastation. A full-blown eruption of the Italian caldera would kill up to several million people within a few days. Dozens of towns and cities in and near the Campanian area of southern Italy, including Naples and Salerno, would be utterly destroyed by fire caused by the initial shock wave and the huge pyroclastic flow that would roll out from the crater. A thousand square miles of southern Italy would virtually cease to exist. Nearby Pompeii and Herculaneum (two Roman towns destroyed by Vesuvius in A.D. 79) would simply be reburied along with two thousand years of subsequent southern Italian history. Scientists monitoring the Campanian/Campi Flegrei caldera would probably be able to give only a few days’ notice of the timing and expected scale of any impending eruption. To evacuate at least four million people from a thousand square miles of territory in such a short time would probably prove impossible.
In the United States, neither the Yellowstone nor the Long Valley caldera is located anywhere near a large population center, and evacuation would probably prove easier—although Las Vegas and Phoenix would almost certainly be thrown into chaos by ash falls from any major Long Valley explosion. Both cities would be covered in a three-foot-thick blanket of volcanic dust.
In the West as a whole, the main immediate consequence of any large calderic explosion anywhere in the Northern Hemisphere or the tropics would be economic and political. Much of western Europe’s and North America’s wealth depends on worldwide trade and international investments that also involve the Third World. If much of Asia and Africa was plunged into demographic, agricultural, and political chaos, the West would quickly feel the draft. This would almost certainly lead to a downturn in western economies, already likely to be enduring food and gasoline rationing, and a slump would obviously create substantial unemployment.
Not all countries in Europe would be hit equally—and this in itself would impose major political strains within the European Community.
Inevitable U.S. and European attempts to use their wealth to import scarce food from a famine-hit Third World, the West’s inability to deliver effective aid, and inevitable fury over Western attempts to repel refugees would combine to inflame Third World public opinion against the West. The event would have the long-term effect of reducing Western involvement in, and power over, the Third World. Europe, North America, and potentially Australia would probably develop a siege mentality and become increasingly isolated.
Significantly, this would have the related long-term effect of freeing up the Third World, removing superpower influence over it. Its debt burden would simply vanish. The disaster would no doubt allow some Third World countries to dominate others in a way that Western economic, political, and military influence has prevented up till now. And the famines and epidemics might well also lead to the strengthening of fundamentalist religious movements.
In the long term, the catastrophe would, I believe, have the effect of reducing the geopolitical imbalance between the West and the Third World. Although Asia, Africa, and possibly South America would lose hundreds of millions of their inhabitants to famine and disease, they would in the end emerge stronger rather than weaker vis-à-vis the West. Just as the eruption of 535 changed world history and brought the ancient world to a close, so any future supereruption would potentially end our Western-dominated era and usher in—in embryonic form—the geopolitical shape of the distant future.
As the evidence in this book has demonstrated, climate has the potential to change history—not just on a short-term basis but in the long term as well. Volcanic activity is merely one of the triggers that can change climate and wield such power. Global warming (due to increased atmospheric pollution), sunspot activity, meteor or comet impacts, periodic small changes in the shape of the earth’s orbit, and minor changes in the earth’s axis of rotation are all capable of triggering dramatic changes in climate—and human history.5
However, only the future will tell which of these factors, or combinations of them, will determine the direction and nature of our destiny.
APPENDIX
T H E C L I M A T I C E V E N T S O F
T H E M I D – S I X T H C E N T U R Y :
A F I N A L S U R V E Y A N D
A D D I T I O N A L P R O O F
For reasons of narrative style, some historical evidence, scientific data and graphs were not included in the main body of this work. For academic reasons, they are added or expanded on here.
From the Mediterranean region there are five historical sources for the A.D. 535/536 event. A sixth-century historian and prominent church leader, John of Ephesus, wrote that “there was a sign from the sun, the like of which had never been seen and reported before. The sun became dark and its darkness lasted for eighteen months. Each day, it shone for about four hours, and still this light was only a feeble shadow. Everyone declared that the sun would never recover its full light again.”¹ This apocalyptic description was set down in the second volume of his greatest historical work, the Historiae Ecclesiasticae (Church Histories). Sadly, only the third volume has survived fully intact, but luckily, the description of the apparent near-demise of the sun and other fragments of the preceding tome were plagiarized by a much later historian, a patriarch of Antioch called Michael the Syrian, who wrote six centuries later.
As already mentioned at the very beginning of this book, the Roman historian Procopius also described the apparently bizarre behavior of the sun at this exact time. He regarded it as a very bad omen indeed—a sentiment that was to prove only too correct. “And it came about during this year that a most dread portent took place,” he wrote. “For the sun gave forth its light without brightness like the moon during this whole year, and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear, nor such as it is accustomed to shed,” said the historian—a top Palestinian-born government and military official.²
Another sixth-century writer, Zacharias of Mytilene, was the author of a chronicle containing a third account of the 535 and 536 “Dark Sun” event. “The sun began to be darkened by day and the moon by night,” he recorded.³
A fourth account was written by a Roman official and academic of Anatolian origin known as John the Lydian, who reported that “the sun became dim for nearly the whole year.”4
All these reports were compiled by eyewitnesses in the Roman imperial capital, Constantinople. But in Italy, a very senior local civil servant also recorded the solar phenomenon. “The sun seems to have lost its wonted light, and appears of a bluish color. We marvel to see no shadows of our bodies at noon, to feel the mighty vigor of the sun’s heat wa
sted into feebleness, and the phenomena which accompany a transitory eclipse prolonged through almost a whole year,” wrote Cassiodorus Senator in late summer 536. “The moon too, even when its orb is full, is empty of its natural splendor,” he added.5
It wasn’t just the sun’s light that appeared to be reduced. Its heat seemed weakened as well. Unseasonable frosts disrupted agriculture. “We have had a spring without mildness and a summer without heat,” wrote Cassiodorus. “The months which should have been maturing the crops have been chilled by north winds. Rain is denied and the reaper fears new frosts.”
In normally warm Mesopotamia, the winter was “a severe one, so much so that from the large and unwonted quantity of snow, the birds perished,” and there was “distress among men,” says the chronicle written by Zacharias of Mytilene.
