Friday, May 7, 2010

The Shape of Disaster

 Island of Santorini
If you close your eyes and picture the Greek Islands, chances are good that you will imagine white stucco villages perched upon steep cliffs and brilliant blue domes surrounded by azure seas. This is Santorini – an island at the southern reaches of the Aegean Sea. The most photographed place in the Greek islands and the most popular tourist destination in Greece. This is a place I imagined going to for over ten years, its exotic location half way around the world and the mysteries that are entwined in its history made it irresistible to me. When I finally had the opportunity to visit Santorini, my mental picture of the island changed dramatically.

When the plane touched down, I looked out my window expecting to see familiar images from photographs. Instead I saw dry grasses and rocky hills tinted orange by the rising sun. Getting off the plane and trudging through the heat waves coming off the tarmac, I expected to enter a posh climate controlled airport terminal filled with sophisticated travelers and wealthy tycoons. But, there were no porters or families to greet us as we continued through the small open-air terminal to the curb, and I began to seriously doubt the validity of this mythical place of beauty.

Santorini airstrip
For over two million years, Santorini has been transformed by one catastrophic disaster after another. Once the heart of a thriving wealthy civilization, it was devastated by a massive volcanic eruption. Then hardy villagers were buried by earthquakes. Now a volcanic chain off-shore quivers in anticipation of its next display of force. As I explored her secrets, my impression of this mysterious island continued to transform as well.

Santorini began as an unimpressive small rocky island. As the African and European plates collided, a volcanic arc developed across the Aegean Sea stringing together Turkey and the Greek mainland with Santorini like a pearl on the strand. Volcanic activity began reshaping the island into two huge shield volcanoes. These volcanoes erupted for 300,000 years, creating a large caldera surrounded by the remains of the volcanoes.

The first morning I was surprised to find a pile of email waiting to be opened. Everyone wanted to know if I was all right. Apparently there had been an earthquake the day before. This is such a common event; no one on Santorini is alarmed by a little tremor. This made me wonder why I was so attracted to such a vulnerable and potentially dangerous place. Even more puzzling is how many people have been seduced by the mysterious call of Santorini for thousands of years.

The first people arrived here during the Neolithic period. These early people built simple shelters from brick and rocks or dug their homes into the cliffs with dome-ceilined rooms that were earthquake resistant. They grew wheat, barley and lentils and raised small livestock animals. About 5,000 years ago more people arrived from Crete. These people named the island Strogoli meaning “round”. Over the next 2,000 years the inhabitants moved from their cave homes and shelters into organized villages where elaborate palaces were built. Art was incorporated into daily life through sculpture, colorful wall frescos, bronze tools, written language, delicate pottery and jewelry. This occurs during the height of the Bronze Age, when merchant ports connected trade routes between Asia, Egypt, Cyprus and the nearby Cycladic Islands. The Minoan Navy of Crete protected these port cities. Akrotiri, a small settlement on the southern tip of Santorini, became a wealthy and spectacular city with multi-storied buildings surrounded by cultivated land rich in olive trees and terraced fields of grain. The art and architecture of this city was heavily influenced by the thriving Minoan civilization of Crete. The business centers and palaces were decorated from floor to ceiling in colorful renditions of daily life. Laws and trade agreements were documented in a language that is yet to be deciphered.

Ruins of the city of Akrotiri.  Photo by: http://www.travel-to-santorini.com/photo.php?photo_id=405

In 1645 BC, this thriving island civilization came to an abrupt end with one of the fiercest eruptions of all history. The volcanic exposivity index (VEI) for this eruption was greater than 7, which puts it above the VEI of 7 for Tambora and well above Mt. St. Helens with a VEI of 5. This eruption completely reshaped the island again. A precursor to the eruption shook the island with tremors and deposited ash over the southern end of the island including the wealthy port at Akrotiri. This city is now called the “Minoan Pompeii” because it was so well preserved by being completely buried in ash by the main eruption. Everyday items have been found right where people set them down when they evacuated. There were no bodies found in the city, meaning that the precursor event may have served as a warning to the inhabitants allowing them to escape before the eruption gained its full momentum.

About a month after the precursor event the main eruption began. Over the next few days the island progressed through four phases of eruptive destruction.

The first phase began with earthquakes and eruptions of pumice and ash that ejected 30 km into the air, covering the entire island. During the second phase, the center of the island collapsed sending a wave of searing hot water, debris and ash over the ridge of the volcano depositing a large new coastal plain on the far side. The collapse of the caldera produced tsunamis that radiated in every direction from the island. Fiery boulders 5 meters in diameter were launched like bombs and rained down with the pumice and ash. During the third phase the most massive pyroclastic flows and immense quantities of ash and pumice were deposited in 55-meter thick layers. All of the particles now injected into the atmosphere caused lightning and rainstorms during the fourth phase. Mud slides and flooding created deposits on the ocean floor south of the island 20-30 meters deep. This transformed the island from nearly a full circle of land to a broken crescent. Today evidence of the eruption is easily recognizable in cliff-faces all over the island. The Bronze Age layer is clearly visible with all the destruction layers piled on top.

Ash deposit from the Bronze Age eruption of Santorini
After the eruption, the people of Santorini and the entire Minoan civilization completely vanished. The ancient Greek philosopher Plato wrote about a spectacular lost paradise called Atlantis. The clues in his dialogs make Santorini and the Bronze Age eruption a convincing candidate for inspiring this legend. In fact, many theories have been suggested to explain the disappearance of the Minoans, such as a change in climate caused by the eruption that made agriculture impossible, ports and trade routes destroyed by tsunamis or buried in ash, war or famine just to mention a few. No one knows why for sure, but if this eruption had the power to reshape an island, it certainly could have destroyed a civilization as easily. This is the end of the Bronze Age.

Several hundred years after the eruption, people were drawn again to the island. The Dorian Greeks came and named the island Thera after their king. For the next nine hundred years, the island was at rest, while people fought over control of the land. Persians, Spartans, Turks all conquered and ruled the island. In 1204, in the midst of the volcano’s reawakening, the Venetians came to power and renamed the island yet again as Santorini. Over the next few centuries, eruptions rocked the island haphazardly and the Ottoman Turks gained power once again.

In 1830, the Greeks finally regained control of Santorini and it became part of the Greek Republic. By the 1900’s the island was a forgotten land, populated by a few hardy souls who led simple lives with very limited water, surviving on dried bread, tomato paste, fava beans and wine. They had little contact with the outside world. Today you can see evidence of their adaptation to these hardships in the agricultural practices. Grape vines are planted in bowl-shaped depressions in the ground and the vines are trained to grow in a circular wreath-like shape to protect them from the sun and wind and to conserve water. Tomatoes are grown low to the ground and allowed to dry up before harvesting the small red fruits. They have a delicious intense flavor that the island has become well known for.

It’s completely quiet when I wake up in the morning. I walk outside and watch the pink sunrise mist creep over the rim of the caldera. It took me a while to figure out why the silence seemed so profound. The cicadas. Normally at the first hint of light these beetles start buzzing and they don’t stop until dark. There are no cicadas here because there are no trees for them. It feels eerie and still. Not exactly what I thought a bustling port town would be like in the morning.

Morning mist over the caldera rim, Santorini
Disaster struck again in 1956. An earthquake, 7.8 on the Richter Scale, destroyed the cities of Santorini, burying women and children in the rubble of their homes while men hurried back from the fields to search for their families. Many survivors left the island and the few who were left took on the task of rebuilding. Even today as you walk through the towns or sit in café’s you can see abandoned ruins among the freshly painted tavernas and pensions that have been rebuilt. The people of Santorini have a different concept of time than Americans. It takes a lifetime to build something because there are no mortgages and homes are built a piece at a time, as money becomes available. It may take 30 years to build a house, so a disaster like this has lasting effects.

The architecture of the island is one of the things that make it so unique and attractive. During the heat of the day the bright cool cascades of white and blue domed buildings flowing over the calderas rim soften the otherwise dry, rocky harsh landscape. The modern architecture is like a reflection of the dome-ceilined caves. Juxtaposed with subtle reminders of its disastrous past, the homes and buildings lend a romantic but vulnerable feel to the island. From a balcony you can watch the sky turn crimson as the sun sets behind the small islands in the caldera that continue to smolder.

Sunset beyond the caldera, Santorini
No longer a center for trade and with limited resources to rely upon for economic stability, Santorini has become an international resort, drawing people from around the world to the edge of the caldera to marvel at this nervous and unpredictable beauty. The Greeks have learned to harness this new resource by attracting cruise ships. Each morning the ships glide into the caldera and release herds of tourists onto its docks. An air-conditioned gondola speeds the sweaty beasts to the top of the rim and deposits them on the main walk. The adventurous few will pay for a more traditional arrival and be carried up the manure scented zigzag trail by donkey. After a day of shopping and dining they are whisked back to their ship and sail off into the sunset. This arrangement encourages the highest input of money to the island with the lowest drain on resources. It also allows the locals to leave during the winter to harvest olives or work elsewhere.

With this long history of disasters reshaping the island and people, it’s only natural to wonder what is next for Santorini. Just 7 km NE of Santorini, the waves dance over the rim of another caldera. Colombo, the largest in a chain of 20 underwater volcanoes trailing in Santorini’s wake, is just 10 m below sea level with a crater 1.5 km across. It erupted in 1650 with enough force to kill 70 people on the island. Today Colombo has been rumbling under the sea with hundreds of earthquakes in the last decade.

In 2006 a team of scientist from the University of Rhode Island and the Hellenic Center for Marine Research explored Columbo with Remote Operated Vehicles (ROV’s). They found gas and fluids spewing from hydrothermal vents in the underwater crater at 224 C, these vents have created mineralized chimneys up to 4 m high. “The high temperature of the vents tells us that the volcano is alive and healthy and there is magma near the surface,” explained Steven Carey, a co-leader of the expedition.

Although the probability of an event like the Bronze Age eruption is very low, the volcano is active and dangerous with the potential to create very destructive impacts on the shores of Santorini and other nearby islands. “When you look at the seismic activity, the earthquake distributions in the area, almost all of the activity is in the Columbo field,” says Sigurdsson, the expedition co-leader. “It’s clear that there should be more focus on the study of that area, from a hazards point of view.” And he adds, “the average person in Santorini says they’re much more afraid of Columbo.”

As I sit in Melina’s Taverna in Akrotiri, I watch a young boy perform an impromptu Greek jig ending with an enthusiastic “Opah!” on the deck of a small boat. When he starts chanting his advertisement for tours to the red sand beach, I turn my attention to our host. Nikos helps his mother run the taverna and he is very worried about Colombo. He’s been fishing around Santorini his whole life and he says there are no fish near the volcano. He asks the geologist with me what he thinks about the volcano. He tells Nikos that it’s very dangerous because it will erupt again but we cannot predict when that will happen. With no warning system on the island, Nikos’ family is in great danger of the effects of a tsunami from an eruption. He lives near the Bronze Age city of Akrotiri, which is a daily reminder of how dangerous this area can be.

Our Greek fisherman
I look out at the sparkling blue water and think of how easy it is to forget how vulnerable this place is because of its beauty. This island is not the dreamy mystical place I dreamt of, it's much more than that.

(All photos by author unless noted)