The Attacking Ocean (23 page)

Figure 9.4
Water lock employees examine the water lock at Suzhou, Shanghai, in 2009, about three meters above sea level, designed to protect the city against sea level rise. AP Photo/Eugene Hoshiko.

Shanghai authorities think that the city can survive rising sea levels until 2100 with currently enacted or planned infrastructure investments. But longer-term planning requires different measures. One palliative under consideration involves the construction of a floodgate near the Yangtze estuary, the gates being raised or lowered according to the dictates of tide and weather, thereby controlling water flowing in and out of the river. Shanghai has already spent over six billion dollars on flood defenses over the past decade; a floodgate might be more cost-effective, despite concerns over the environmental and commercial impacts of the project. Meanwhile, the city is becoming ever more vulnerable, in part because of aggressive reclamation of coastal wetlands in response to a land shortage. These wetlands have provided a natural barrier against inundation for hundreds of years. Now most of them are gone. In the long term, perhaps the best strategy might be to move away from expanded industrial activity into less aggressive impacts on the environment. For instance, the city is planning to foster economic activities such as banking, which do not require land-hungry factories.

WE HUMANS ARE opportunistic and voracious when we settle at strategic locations on the world’s coast. Shanghai epitomizes the dilemma faced by an industrial economy that depends on foreign investment and trade for its livelihood. Protective wetlands vanish daily; aggressive industrial development continues unabated. The authorities invest heavily on sea defenses, with no guarantee that they will work in the very long term. They really have no other option, given the impossibility of moving millions of people inland. Shanghai faces the same unhappy prospects as Bangladesh—millions of people, settled on low-lying terrain, powerless to react to an ever-accelerating vulnerability. The future will define Shanghai’s appalling dilemma with frightening clarity. Solutions lie not in immediate panic measures or inflated political rhetoric, but in deliberate, carefully measured long-term planning.

10
“Wave in the Harbor”

Northern Japan, A summer morning, 3000 B.C.E. Clusters of brush dwellings dug partially into the ground lie in a forest clearing atop the ridges overlooking the bay. Woodsmoke wafts idly above the dark treetops. Two women scrape a hide pegged out on the ground near a smoldering hearth. A young man and his father emerge from the trees hefting the carcass of a deer. Children cluster around the fresh kill asking questions about the hunt. The village looks down on the wide bay and its sandy beach, where dark figures climb on the rocks, fish spears in hand. Three young girls pry mollusks off rocks exposed by the falling tide and cast them into a skin cloak that doubles as a container.

High above on the ridge, three elders gaze out over the ocean, as they do every morning as the sun climbs in the heavens, talking quietly among themselves. Suddenly the ground starts shaking. Startled birds fly from the trees in cacophonous fear. The heavy shaking continues. An irregular rolling and thumping dislodges boulders from the nearby cliffs. Except for the children, everyone has experienced this before. Both in camp and by the shore, everyone crouches instinctively on the ground, mothers clasping their children. Fishermen on the rocks jump for safety into the sea.

As the shaking subsides, the elders leap to their feet and watch the ocean, calling loudly to everyone and beckoning people by the shore urgently back to camp and onto higher ground. Suddenly the water starts to recede far below low tide. As fish flap helplessly and the ocean becomes dry land, young and old alike run as fast as they can up the ridge
and then to even higher ground behind the camp. Safe above the bay, the people turn seaward just as some loud booms and a deep roar assault their ears. A great wave flows rapidly inshore and breaks loudly at the foot of the ridge, throwing spray high into the air. Moments later, an enormous wave follows in its wake, this one far higher than two or three men. Great torrents of water surge up the slopes of the ridge, slowing just as they reach more level ground and the edge of the village. More waves attack the shore, but with less force than their predecessors. Soon the water retreats as fast as it arrived and the ocean resumes its normal calm. The beach and the low ground behind it are now a barren landscape of sand and rocks, but, thanks to deeply ingrained cultural awareness of tsunamis passed from one generation to the next, the villagers have survived.

AN EARLY ACCOUNT of a Japanese tsunami appears in the
Nihon Sandai Jitsuroku, The True History of Three Reigns of Japan
, written in 901 C.E. On July 13, 869, “Some time after severe seismic shocks, a gigantic wave reached the coast and invaded [the] entire Sendai plain. Rising seawater flooded an old castle town … causing the loss of 1,000 lives.”
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The word
tsu-nami
, in use in Japan since the 1600s, means “wave in the harbor,” apparently a reflection of the devastation witnessed by fisherman returning home after a major tsunami had swept ashore. Great tsunamis punctuate Japanese history from its beginning. We can be certain that vivid recollections of many of them remained etched into generational memory for centuries afterward. Tsunamis offer a dramatic lesson in the importance of cultural traditions in surviving the vagaries of the attacking sea.

Japan has always rocked and rolled, lying as it does on the notorious Pacific Ring of Fire. Around the Pacific Rim, great tectonic plates clash against one another, displace seawater, and give birth to destructive tsunamis. Some 53 percent of all tsunamis occur in the Pacific. Over 80 percent of them result from submarine earthquakes. Tsunami waves move forward with tremendous power, literally a solid wall that acts like a bulldozer. Instead of expending its force by breaking, a tsunami
continues to surge inland until friction or a steep gradient slows it. Once the momentum of return develops, it is extremely powerful and drains away with tremendous force, carrying people and property, even entire buildings, out to sea.
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As the world learned the hard way from the Aceh tsunami that struck Southeast Asia and the Indian Ocean in 2004, such events are about the most dangerous assaults the ocean can unleash on humanity. They strike without notice, give virtually no hint of their coming, and can wipe out virtually everything in their path. You can forecast a tropical cyclone and its sea surge a few days ahead, enough time to track their arrival. But tsunamis develop, sometimes without warning, are usually lethal, and, in a future world of higher sea levels and much denser coastal populations, are a frightening menace.

TSUNAMIS ATTACKED JAPAN long before humans settled there some twenty-five thousand years ago, but it was not until thousands of years later that they caused major social disruption. During the late Ice Age, Japan’s four main islands formed a single landmass, connected to the Asian mainland. A land bridge joined what is now Hokkaido in the north to Sakhalin. Coniferous forests covered the landscape at a time when temperatures were much lower than today across a tract of dry land that was about the size of California. When global warming accelerated after fifteen thousand years ago, sea levels rose quickly in Japan, just as they did elsewhere, at times as much as 2.5 meters a century, owing to rapid release of glacial meltwater. The overall sea level height was about twenty to thirty meters below modern levels eleven thousand years ago. Thereafter, the climate warmed rapidly. Sea levels reached a height about two to six meters above modern levels around 5400 to 3900 B.C.E., just as they did along the coast of the East China Sea. Thereafter there was a slight retreat to about one to three meters below modern levels between 2500 B.C.E. to 1 C.E. in some places.

Profound environmental changes accompanied sea level rise. The coniferous forests of earlier times gave way to temperate deciduous and evergreen broadleaf forests. Nut trees abounded. What had once been a plain became the shallow Sea of Japan. The new archipelago abounded in sheltered bays, tidal flats and wetlands, and estuaries where fish, mollusks, and other seafood abounded. At the same time, the large game animals such as the elephant and bison of earlier times gave way to medium-size and small species such as the sika deer and wild pigs.

Figure 10.1
Map showing locations in
Chapter 10
.

The newly fashioned archipelago was a veritable paradise for the hunters and foragers who had eked out a living in what is now Japan for at least twenty-five thousand years. As the vegetation changed and sea levels rose, Jomon society emerged on the islands—hunters, foragers, and fisherfolk, who may have originated on the Asian mainland, perhaps in the Amur River valley of Northern China.
³
The archaeological
term Jomon means “cord-decorated,” after the distinctive cord-decorated pots found in their settlements, for the Jomon people were among the earliest potters in the world—at least sixteen thousand years ago.

Bark, leather bags made from stomachs and intestines, ostrich eggshells, seashells, and wooden trays—ancient hunter-gatherers used an impressive array of simple containers, many of them improvised for specific tasks like collecting honey. Bowls and pots fashioned from fired clay are quite another matter, not because someone invented a brand-new technology—fired clay was familiar to Ice Age people in many places as early as twenty-five thousand years ago. What was new were durable, waterproof receptacles, which could be used to store food and water, and, above all, for cooking or for steaming various foods. Shellfish could be opened easier; small children could be fed soft foods, thereby shortening weaning periods and permitting closer-spaced births; toothless old people could now be fed easily, allowing them to live longer. Since the elderly were repositories of ritual and spiritual belief, of cultural knowledge of all kinds, their potentially longer life expectancy was no small matter.

This would have been especially true in a world where many people lived by the coast and were at risk from tsunamis. Thanks to an abundance of nuts and other plant foods, many groups stayed in the same villages for long periods of time. Reduced mobility increased vulnerability to tsunamis, making generational memory of such events even more important. So did an increasing reliance on estuaries and bays, on coastal wetlands, fish, mollusks, and sea mammals, foods so abundant that people lived for long periods in the same spots, close to the high tide mark. The ocean, like the land, became a conscious part of the Jomon landscape.

Imagine a calm bay, deep water lying close offshore. A Jomon village lies on a low headland overlooking the ocean. On calm days, the hunters watch dolphin gamboling close inshore. An unsuspecting school feeds in the deeper water of the continental shelf close to the inlet. The fishermen launch their dugout canoes and paddle a short distance offshore, piles of stone cobbles in the bottoms of their craft. They fan out to encircle the feeding mammals. The leader gives a signal. The crewmen grab cobbles and knock them together below the surface. Confused by
the unfamiliar cacophony, the school swims to and fro, disoriented by the unfamiliar resonance. The lead dolphin steers the confused beasts away from the noise into the shallows of the narrow bay as the canoes close in. Men, women, and children rush into the shallows and literally fling the helpless dolphins ashore. Sometimes they grab the beasts, holding them softly by the mouth and guiding them alongside the canoes where spearmen dispatch them in short order. Once the hunt is over, the butchery begins. The women cut long strips of dolphin flesh and hang them on wooden racks to dry in the sun and wind.

It is an imaginary hunt, but a scenario based on traditional dolphin hunting methods that were commonly used in many parts of the world in ancient times. Jomon groups did far more than hunt dolphin. Entire villages harvested the great salmon runs of spring and fall, used river weirs to trap smaller fish, often prized not so much for their flesh as their high oil content. Nor were Jomon fishermen afraid to venture into deeper water, where they caught tuna as they migrated close inshore. Many of the species they took, like salmon or tuna, yielded flesh that could be smoked or dried for later use, providing a stable food supply so that many coastal settlements remained in use for many months, even year-round.
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