Sunday, June 1, 2014

Those Lovely Greek Islands: The Time One Exploded

The other day I opened a big coffee-table book called the Eternal Sea. It's full of gorgeous photographs of the world's oceans, but what really blew my hair back was an aerial view of an ancient-looking village perched on the edge of a cliff overlooking the sea. "Where is THAT?" I thought, "and how can I get there?"

The image below isn't quite as stunning as the one in the book, but it gives the basic idea. It looks like the kind of place where you could trip walking out your front door and tumble a thousand feet into the sea.

When I looked up more information on the town, I realized I had seen it in many pictures before, but not from that angle. The town is Thira (sometimes called Fira), one of those gorgeous whitewashed villages in the Greek islands. But most images of it it aren't as dangerous-looking as the one I saw. I guess they want people who are afraid of heights to visit, too, though I'm guessing some of them cower in their rooms when they get there. Most images look more like the one below, which shows the more-photographed town of Oia, also on Santorini:

The wide-angle images give a different, and rather jarring, perspective on these idyllic Greek villages. They're perched on the rim of a volcano. The semi-circular cliffs of Santorini are the rim of a caldera--an ancient volcano whose center erupted, and then collapsed and filled with water. The satellite image below shows that most of Santorini made of this caldera. The two islands in the center are newer volcanic formations that have risen in historic times. The Roman historian Cassius Dio recorded the formation of the smaller one in 47 AD, writing, "This year a small islet, hitherto unknown, made an appearance close to the island of Thera." The bigger island is an active volcano which declares its presence every few decades with a minor eruption. But those are just baby blasts. The caldera itself was formed by a series of massive, cataclysmic eruptions over the last few hundred thousand years.

The scenic little towns on Santorini, then, are precarious in more ways than one. They aren't just at the edge of cliffs. They're built on one of the world's biggest natural bombs.

The last of Santorini's major eruptions occurred around 1600 BC. At that time, the Minoan civilization was a major maritime power in the eastern Mediterranean. Based on the island of Crete and already over 1000 years old, the Minoans seem to have gained their power through trade instead of warfare. Crete was well-placed to be a trading center; a sort of Singapore of the ancient Mediterranean. Today most people know the Minoans from their graceful, naturalistic art, which sometimes depects a mysterious bull-jumping ritual. These scenes reminded the archaeologist Arthur Evans of the Greek legend of the Minotaur, so he named them "Minoans", but we have no idea what they called themselves. We do know they were a wealthy people, and their art gives the impression that they were peaceful and happy, but it's hard to know if that's really true, because hardly any of their writings have been deciphered.

It's interesting to speculate about how western civilization might have developed if Minoan civilization had lasted longer. What if they had retained their dominance and prevented the Greeks from forming the foundation for so much of European culture? What would our architecture be like now? Our philosophy? Religion? There's no way to know, but could have turned out that way quite easily. What kept if from happening may be one single event: the eruption of Santorini, then known as Thera.

The Thera eruption devastated Crete and utterly destroyed a Minoan settlement on Santorini, now called Akrotiri. It was a cataclysm on an almost unimaginable scale. Before the eruption, Santorini was an nearly complete ring, with a central volcano much bigger than the one today. This ancient volcano is what detonated in one of the biggest explosions in history. Imagine a cube of rock with sides 2.4 miles across. That's how much rock, lava, and ash were blasted into the sky. Some of it ascended 22 miles into the statosphere, forming a giant, fiery thunderhead that flashed lightning and rained boulders. The falling ash and pumice covered and preserved the village of Akrotiri (whose inhabitants had prudently fled.)

This initual eruption was followed by scorching clouds of gas and rock called pyroclastic flows, which raced across the surface of the island at hundreds of feet per second, obliterating any life in their path. Bizarrely enough, they even raced across the surface of the sea, covering shorelines many miles away with hot debris (the same thing happened when another island, Krakatoa, exploded in 1883.) Having ejected so much material out of its core, the volcano collapsed in on itself, taking parts of the older Santorini caldera with it. This caused a huge tsunami which smashed the northern coast of Crete, knocking buildings off their foundations and devastating the heart of the Minoan civilization.

It would never recover. The Minoans lost influence in the Mediterranean, and were finally overrun around 1400 BC by the more warlike, Greek-speaking Myceneans. Some people think the Minoans were the inspiration for the ancient myth of Atlantis, but there's no real proof of that. Besides, the geography doesn't match--Atlantis was supposed to be beyond the Pillars of Hercules, in the Atlantic Ocean. Personally, I can't get that excited about the Atlantis connection. For all we know it's just a legend. The story of Santorini and the Minoans is a fact, but it's as a story as epic as any legend.