In the shadow of the GIANTS.
WHATEVER HAPPENS, they are going to have to drag me away from here," said one defiant woman who runs a food stall a few kilometers Popocatepetl in Mexico. "I would rather live and die by the moods of Don Goyo than have to move to the city and face its pollution and crime." Despite Popocatepetls recent bout of activity -- since June 1997 it has twice showered Mexico City with ash -- many of the 300,000 people living on the flanks of Popocatepetl seem determined to inhabit the area for some time to come. But the fact remains that Popocatepetl's proximity to Mexico City makes this volcano potentially one of the world's most lethal assassins.
No fewer than 11 of Mexico's 3,000 volcanoes are active today, accounting for six per cent of the planet's total active volcanoes. This awesome abundance of firepower puts Mexico in the top flight of the world's volcanic activity league, matched only by a handful of other nations which, like Mexico, form part of the Pacific `Ring of Fire'. But unlike other volcanic countries such as Japan, the Philippines and Indonesia, Mexico's population over the last few decades has grown considerably in areas within easy reach of the flames and fury of its most dangerous volcanoes.
In the space of a year, they have sprayed some of the country's major cities in ash, caused numerous villages to be evacuated, exhaled ash plumes more than 13 kilometres into the air and prompted Mexico City's airport to be shut down. In several parts of Mexico a state of alert has become the norm.
Popocatepetl (the `smoking mountain' in the Nahuatl language of the Aztecs) lies a mere 70 kilometres from Mexico City -- the world's most populated metropolis with a population of 20 million and rising. Standing at 5,465 metres, Popocatepetl is higher than any mountain in Europe, but it is still only the second tallest volcano in the country. It is, however, the most enigmatic, and over the centuries its fiery temper has convinced Mexicans that it possesses a human personality, a feature reflected in the names it has been given, such as El Popo, Don Gregorio and Don Goyo.
It also has an uncanny knack of timing its eruptions to coincide with important events in Mexican society, and a common belief to this day is that it acts as a watchdog for the nation, expressing its discontent in times of crisis. It erupted in 1519 in protest at the arrival of Herngn Cortes and the Conquistadors from Spain. In December 1994 it was again vociferous when severe economic problems led to the devaluation of the peso, halving the Mexican's purchasing power overnight. Its views on the outcome of the recent presidential elections are eagerly awaited too, and will no doubt be taken by the nation as a vote of approval or rejection of their choice of president.
Popocatepetl's most violent eruption occurred 23,000 years ago, shortly before the arrival of the first settlers to Mesoamerica, when it fired debris 80 kilometres away, threw a mushroom-shaped column of smoke 30 kilometres into the sky and created a lunar landscape within a 50-kilometre radius. Since then it has had immense eruptions 11,000, 9,000 and 7,000 years ago, by which time the region had been settled.
HOT AND READY TO TROT
Over the last few months the other two of Mexico's `big three' -- El Volcan de Fuego and El Pico de Orizaba -- have reminded the nation of their presence in the most emphatic manner.
On 10 February this year El Volcan de Fuego de Colima (The Volcano of Fire) on the border between the Pacific states of Colima and Jalisco burst into the limelight with several eruptions of considerable force, ejecting burning boulders five kilometres from its crater and scattering ash over a radius of 25 kilometres. The result was a number of extensive forest fires and the immediate evacuation of three nearby villages. This volcano, standing 3,842 metres above sea level, is one of the most consistently active in the North American continent, and over the last 500 years has shown a marked upsurge in its activity. In this time it has erupted dozens of times, but tends to have one Vesuvius-sized detonation -- capable of depositing a 25cm layer of ash 15 kilometres away -- on average every 100 years. The last on this scale took place in 1913, an event which blasted out a crater 500 metres deep and darkened the skies with a smoke column 21 kilometres long. There have been smaller explosions in recent years, such as 1975, 1987, 1994 and 1998.
Following further eruptions in May, volcanologists now believe that the Volcano of Fire is entering a similar explosive phase to those that led to the huge eruptions of 1903 and 1913. But in spite of the ominous signs, the residents of Colima, a city of some 130,000 inhabitants 30 kilometres from the volcano, and capital of the state with the same name, are as reluctant to take evasive action as the neighbours of Don Goyo. "There are so many gullies and ravines between it and the city that it is virtually impossible for any lava flows to reach us here," said Jaime, a lifelong resident of Colima. "Even the smoke and ash don't bother us, as that all gets blown northwards by the wind."
Northwards, however, means the villages of the state of Jalisco and its capital Guadalajara, the country's second biggest city and home to more than four million people. During the 1913 eruption, ash rained on Guadalajara 100 kilometres away, and even reached the city of Saltillo, 720 kilometres to the north. Studies have shown that a similar occurrence today would cause a dramatic rise in respiratory problems and strain the medical services beyond their limit. In 1998, following a far smaller eruption of Popocatepetl, hospitals in Mexico City and other populatio centres reported notable increases in admissions for breathing difficulties.
But most at risk would be the villages close to the volcano, where the upheaval caused by evacuations have almost become a part of everyday life. "The problem caused by the numerous evacuations of villages near Popocatepetl and el Volcan de Fuego is that the locals see that the threatened big eruption never happens and they get tired of the disruption caused by leaving their homes and their jobs," says Dr Juan Manuel Espindola, a researcher at the Institute of Geophysics at the National Autonomous University of Mexico. "This makes them increasingly reluctant to move and one day they may simply refuse to budge when the threat is real but by the time they realise this it will be too late."
It was precisely this indifference that led to a catastrophe in 1992 when three months of intense activity by the Chichonal volcano in Chiapas went unheeded by both the authorities and the local population. No evacuations occurred and no emergency plan was put into effect. But the emergency did arise and a vast eruption took place obliterating everything within a 12-kilometre radius, including a dozen villages and 2,000 lives. Such was the force of the blast that ash fell in thick sheets on towns over 2,000 kilometres away.
HUFFING AND PUFFING
The titan of the Mexican giants is El Pico de Orizaba (also known by its Aztec name Citaltepetl, meaning the Star Mountain) near the border of the states of Veracruz and Puebla. Rising like a colossus over the town of Orizaba, this volcano is the third highest mountain of the North American continent, soaring 5,747 metres above sea level. Its last major eruption took place in 1687 but over the last few months it has been emitting fumaroles and causing minor tremors. This activity in itself is mild, yet its main threat lies in the fact that Orizaba was built precisely on top of the lava flows created by eruptions in the past; in the event of another major explosion, lava would follow the same route and turn Orizaba into a Mesoamerican Pompeii. Also in its line of fire is the state capital of Puebla, a sizeable city which is additionally closer to Popocatepetl than Mexico City.
Like Don Goyo and the dormant Iztaccihuatl, El Pico de Orizaba is part of a huge mountainous area running through central Mexico known as the Mexican Volcanic Belt. This area sweeps east to west from the Gulf of Mexico to the Pacific coast, and north to south from the arid states of Zacatecas and San Luis Potosi to the tropical vegetation of Oaxaca and Guerrero, and includes the most densely populated areas of the country. It also boasts El Nevado de Toluca, La Malinche and Paricutin, the American continent's newest volcano, which celebrated its birth in 1943 by churning out an estimated billion tons of lava, destroying a dozen villages and creating a mountain more than 400 metres high.
Another volcano that forms part of this belt is Xitle, which erupted in 400AD, covering the pre-hispanic settlement of Cuicuilco in a sea of lava. Since then, a large swathe of the south of Mexico City (including the campus of the National Autonomous University of Mexico) has been built on top of this lava bed, and Cuicuilco has been absorbed as one of the capital's districts. Fortunately, Xitle is not active at present.
Volcanologists have a large arsenal of techniques for predicting eruptions. These include measurements of slopes near volcanic craters to evaluate upward pressure on the surface from below, geological studies that reveal past activity, seismometers to gauge tremors and apparatus which detects gravity and temperature changes.
But the moods of Don Goyo and his counterparts are characterised precisely by their unpredictability. "It's like sleeping next to an elephant," says Dr Espindola. "Maybe you can lie there for hours perfectly safely and nothing happens, or maybe in the next seconds the elephant will roll over because it feels like it and squash you."
Following the Chichonal tragedy, the Mexican authorities set up Civil Protection and CENAPRED (National Centre for the Prevention of Disasters), which have specified a series of evacuation routes, set up camps and arranged for the emergency provision of rescue and supply vehicles in the affected areas. Such measures would, if adequately implemented, prove effective against a moderate to large blast; but what is the probability of a massive catastrophe caused by Mexico's giants? "Major eruptions are part of the past of these volcanoes and they will therefore, without doubt, also be part of their future," says Dr Espindola. "The probabilities are similar to those used by insurance companies for accidents or thefts. Everyone knows they will happen, the only question is when."
Mexico's Pacific coast is the meeting point between two tectonic plates: the Pacific plate which is slowly moving southwards and the North American plate working its way northwards. Farther north, in California, tlnis gives rise to the San Andres Fault, whose constant friction is the cause of some of this century's most dramatic earthquakes. South of the US border the situation is further complicated by a geological anomaly. "The curious thing about Mexico is that while most volcanoes are located on or very near the edges of plates, the volcanoes here are situated well inside the plate," says Dr juan Manuel Espindola, researcher at the Institute of Geophysics of the National Autonomous University of Mexico. More specifically, the big three lie precisely in the central area of Mexico which is home to the majority of its 98 million inhabitants.
The legend of Popocatepetl
Popocatepetl, also known to locals as Don Goyo, is seen as a romantic figure that has inspired a vast array of legends. He lies in front of his beloved Iztaccihuatl, the Sleeping Woman and Mexico's third tallest peak (altitude 5,286m). According to Aztec mythology, this dormant volcano wanted to marry Don Goyo but was not allowed to do so as she was not of the same social rank as him. The result was that she died of grief.
However, another legend has it that they did actually marry, only for Don Goyo to embark upon an affair with La Malinche, a volcano in the eastern state of Tlaxcala. Iztaccihuatl knows of this affair, but is not particularly bothered as her responsibility as the real guardian of the Aztec nation leaves her with little time for her husband.
For the Aztecs, Popocatepetl and Iztaccihuatl represented the duality of male and female, day and night, heaven and earth, which was an essential feature of pre-Hispanic belief. To this day the inhabitants of the nearby village of Paso de Cortes claim to see UFOs regularly entering and leaving the crater of Popocatepetl.