Predicting Storm Surges
The morning of October 4, 1864, in Bengal was beautiful, sunny, and most important, dry. After nearly five months of torrential downpours brought on by the southwest monsoons, several days had now passed with little or no rain.1 Although that five-month rainy season had been fairly typical, the people throughout India were still thankful it was over. The clear morning revealed a lush, green landscape along the coast of the Bay of Bengal, the result of a bounteous supply of water and a million tons of nutrient-rich silt carried to the coast by three mighty rivers—the Meghna, the Brahmaputra, and the sacred Ganges. Much of the sediment had come all the way from the majestic Himalayas. Over the centuries these three rivers had combined to build in Bengal the largest delta on Earth, consisting of thousands of islands and hundreds of channels and, at its seaward edge, the largest mangrove forest in the world. It was a land of Bengal tigers, elephants, and crocodiles, but it was also a land of rice paddies and sugarcane fields carved out of swamps by a million Bengalis. It was a land controlled by the British, whose ships filled the port of Calcutta, eighty miles up the Hooghly River in West Bengal.
On this morning Bengalis and British alike were enjoying the quiet, dry weather now that the rainy season was over, unaware that five hundred miles to the south in the center of the Bay of Bengal rain was falling “as in a solid mass.”2 High winds had been churning the seas for the last three days, but no ships had reached the coast to inform the British. Months later, British scientists working for the newly formed Meteorological Department of India would examine the logs of schooners that had been on the Bay of Bengal that October. And by comparing barometric pressure measurements, they would recognize an area with very low barometric pressure. Around this low-pressure area a huge portion of the atmosphere was rotating counterclockwise, the winds reaching well over a hundred miles per hour near the center. Such a rotating mass of air over the Indian Ocean had been recently given the name cyclone, although it was sometimes called a hurricane like its counterparts in the Atlantic or sometimes called a typhoon like those in the Pacific. Scientists did not yet understand how these violent whirlwinds were created, much less know how to predict their path or wind strength. But they were well aware of the damage cyclones caused, with the help of the sea.
On that October 4, unknown to those on land, the turbulent weather being recorded in logs on ships battling to survive on the Bay of Bengal was part of a major tropical cyclone moving in a north-northwest direction—heading directly toward them. Along the Bengal coast the only indication of a possible change in the pleasant weather was a modification in the direction of the light winds. At noon the center of the cyclone was still two hundred miles to the south, but its northern edge finally reached the Hooghly River in West Bengal, bringing with it stormy weather, much to the chagrin of those on shore who had thought they were finally done with rain. Unfortunately, this cyclone would bring more than rain.
In the evening the cyclone’s full fury began to make itself felt. By 8 P.M. it was blowing violently, which continued throughout the night.3 At around 9 A.M. the next morning the eye of the cyclone passed near Saugor Island in the lower Hooghly, producing forty-five minutes of sudden calm that confused the captains of the many ships anchored there. From the barometric pressure readings the British later acquired from ship logs, this cyclone was probably a Category 4 storm on today’s Saffir-Simpson Hurricane Scale, reducing to a Category 3 after it moved onto land and up the Hooghly. Its violent winds caused a great deal of damage, especially near the eye of the cyclone. But the real danger came not from the air but from the sea, for this cyclone was bringing with it what British scientists in the mid-1800s called a storm wave, what scientists today generally call a storm surge.
A storm wave is not to be confused with one of the thousands of short steep wind waves that came crashing down on decks of ships caught in the cyclone. This was a much longer and wider wave that raised the surface of the sea over hundreds of square miles, and in the process it pushed a huge volume of water toward the coast. Wind waves were present also, but they rode on top of the storm wave and added to the havoc the storm wave would wreak when it reached the shore. In the mid-1800s scientists had yet to learn exactly how storm waves were produced, though they believed it had something to do with the fast winds and low atmospheric pressure. During the morning of October 5, the waters along the coast of West Bengal and the nearby rivers slowly rose, but the crest of the storm wave did not arrive at the mouth of the Hooghly River until a little after 10:00 A.M., about an hour after the cyclone’s eye had passed.4
The timing of the storm wave could not have been worse. Its crest arrived just two hours before the tide reached high water. To make matters worse, it was nearly a full moon, so the height of high water during this spring tide was at its highest. The Hooghly was a shallow river whose width narrowed upstream, so its highest tides formed a steep bore that moved rapidly up the river (as described in Chapter 1). Dikes and embankments along the Hooghly River were high enough to withstand the spring tidal bore but not the bore created by the storm wave. This combination of storm wave and spring tide was overwhelming—not just because its high water levels flooded the land but because the crest arrived suddenly and with great destructive power.
The storm wave picked up the ship Martaban, which had been anchored near the mouth of the Hooghly River, and carried it over normally shallow sandbars without the ship ever coming close to touching the bottom. In spite of the havoc on deck caused by the wind, the rain, and the wind waves breaking on the deck, the captain managed to repeatedly check water depth with a lead line. He later wrote, “The ship never shoaled at less than 7 fathoms” (42 feet), and he estimated that “the storm-wave must at least have risen 40 feet to have carried me across these sands.”5 The storm wave also picked up the river steam vessel Salween, carrying it up onto the shore and over the tops of trees, and putting it down atop the local telegraph office.6
But the storm wave’s real measure of destructive power was the devastation it wreaked on the countryside as the deluge washed over or broke through dikes and embankments, at heights of ten, twenty, or even thirty feet. The storm wave swept away entire villages, leaving little evidence that they had ever existed. It flooded the land as far as ten miles from the banks of rivers and channels. When the captain of the Salween landed on the telegraph office, he discovered sadly that the post office had also been gutted by the storm wave, killing the postmaster and his wife and children, and that the entire native village of Kedgeree had been washed away with all its men, women, and children drowned.7
A similar scene played again and again in village after village over all of West Bengal. To escape the violent winds and the torrential rains, villagers took refuge in their huts. They huddled in the dark with the frightening noise of the roaring winds all around them. But then, “almost in an instant, and without any warning, the water was over the village.”8 The storm wave, appearing like a wall of water, violently swept each hut away, drowning those trapped inside. Of those who somehow were freed from their crumbling homes, a few managed to grab onto floating roofs or pieces of wood, and if they had the strength to hold on until the chaos subsided, they found themselves washed many miles inland. Other lucky ones were able to grab onto trees and hold on for dear life. The great majority of survivors were men, for the women and especially the children did not have the strength to hold onto the trees or floating wood for the hours it took to survive.9 Those lucky enough to be saved by tree branches observed not only the terrible sight of their families being carried away into the mist by the swirling waters, but sometimes strange sights such as “cattle and tigers . . . swept into an indiscriminate mass together . . . the latter . . . powerless to do any harm.”10 Only the strong-swimming water buffaloes seemed able to survive in the wild currents.
The scene of total devastation revealed the next morning was the true indication of the power of the storm wave. Bodies covered the shores and were spread inland for miles. So many floated in the Hooghly River that relief ships from Calcutta had to go slowly to steer around them. They lay in and around every village. The heartbreaking sight of so many bodies of young children was difficult enough for government officials to bear as they tended to survivors, but soon the awful stench made it even worse. In each village bodies were left to rot by surviving villagers because these were the bodies of strangers from some other village. The bodies of their loved ones had been washed miles away, to places unknown, but probably near another village whose surviving inhabitants had also left them to rot. Those who were still alive had more immediate problems. Their food stores had been washed away, and their water tanks had been fouled by saltwater and putrid vegetation. In desperation they ate bad food and drank impure water, which led to an outbreak of cholera, dysentery, and smallpox. People starved, and people died of disease.
It did not take long for the full calamity to become apparent as British officials tabulated losses. At least 100,000 cattle had been drowned. Rice crops were destroyed or damaged by saltwater, many fields already turning black. Entire regions lost more than three-quarters of their population. At least 50,000 people were killed directly by the storm wave, with another 30,000 dying over the following weeks from disease.11 The combined 80,000 death toll was probably a conservative estimate, because it was not known how many migrant workers had been in the area for the upcoming rice harvest.
In Calcutta, eighty miles up the Hooghly River, there were fewer deaths. It was far enough from the coast that the storm wave had decreased in size by the time it reached the city, worn down by friction of the river bottom and also reduced in volume by water lost over riverbanks. If the embankments and dikes downriver had held better, the wave would have been larger at Calcutta, and the city would have suffered worse destruction. The damage that did occur was primarily to ships in the Port of Calcutta. Although diminished when it reached the port, the storm wave was still a steep bore that violently lifted ships at their moorings, pulling out anchors, breaking chains, or if anchor and chain held, pulling the vessels underwater. Ships freed from their moorings “were grounded, a mass of confused wrecks, with cargo-boats, lighters, and smaller boats of every description, on the sands of Goosery, Shibpore, and Cossipore.”12 Of the 195 major vessels in port, only 23 escaped harm, greatly upsetting the shipping companies of London and Liverpool. A witness wrote that “where the eye generally wandered over hundreds of native boats of all sorts and sizes,” after the storm wave “not one was visible; but the water and the shore were covered with minute pieces of plank.”13
The 1864 storm surge was not the first to flood the low-lying Bengal coast and kill so many people, but it was the first to be well documented, in this case by the newly formed Meteorological Department of India. From its reports we get a good picture of the storm surge’s destructive power and its terrible impact on the people, since the British scientists recorded not only statistics but also accounts of survivors. What is evident is that the storm surge came as a complete surprise. People had the moon to help them predict tides, and they understood the seasons well enough to predict when the rainy season should occur, but there were no warning signs that might help the people predict when the sea was about to flood their land.
Similar or even greater death tolls due to storm surges had occurred there countless times over the centuries before 1864, though we have only glimpses of each catastrophe from limited written records. As we look further back in history for evidence of great coastal floods, we must rely on archaeological and geological studies. And while no written accounts of specific catastrophic floods exist, myths and religious documents hint of such events. The earliest known catastrophic flood took place four thousand years ago at the Harappan port of Lothal on the Indian coast of the Gulf of Cambay, connected to the Arabian Sea, which is west of the Bay of Bengal. Lothal was destroyed at least four different times, the worst destruction occurring in 1900 BC, when a large region around the port was leveled by a storm surge.14 Thus it is not surprising that stories of these floods show up in the earliest written religious works of ancient India. The Satapatha Brahmana, written between 800 and 500 BC, recounts a story of a worldwide flood.15 This is India’s equivalent of Noah’s Ark and the Great Flood (or Deluge) in the Book of Genesis. The Indian version is quite similar. The only twist is that the Indian Noah, named Manu, is warned of the great flood by an Indian god name Vishnu, who takes the form of a fish. But the warning is the same—the flood will cover the world and kill evil people—and Manu is told to build a vessel for him and his family and some animals, but in this story the fish god pulls the vessel to safety as the world floods.
Nearly every region of the world has a great-flood story. While this fact is cited as evidence for a real worldwide flood (an impossibility, of course) by those who believe these stories to be true, it has also led to geological investigations by those looking for a real event (but not a worldwide event) that could have inspired one or more of these great-flood stories. Entire books have been devoted to this subject.16 Here we will not go into all the arguments for and against many of the theories that proposed a location or a cause of some large ancient flooding event. We will only say that if there was a catastrophic flood in the distant past that served as the inspiration for the story of Noah’s flood, there are reasons to believe that such a flood would have been caused by a huge storm surge from the sea.
The oldest known great-flood story was written sometime before 2075 BC in Sumerian, the language of the civilization that lived in the lower Euphrates valley at the north end of the Persian Gulf.17 In the following millennium Babylonians lived in the Euphrates valley, and they had their own version of the deluge story. The Babylonian version is very similar to the later Hebrew version in Genesis, which apparently had two authors, the combined result written sometime after 586 BC. There is also a Greek version, as well as a Muslim version in the Koran.18 Many historians and scientists have suggested that if one of these stories was inspired by a real flood, with other storytellers then copying the first story and adding their own details, then the most likely location for that flood was near the mouth of the Euphrates when the Sumerians lived there. Every deluge story involves the prediction of a great flood by some god, and a necessary response by the Noah character in order to save himself and his family, namely, building a vessel of some kind. In this case such “predictions” are prophecies. But the interesting aspect of an ancient gigantic flood occurring in the Euphrates valley at least 4,000 years ago and inspiring the Noah’s Ark stories is that a storm surge makes more sense as the flooding mechanism than does the typically proposed river flood.
A river overflowing from heavy rains initially seems to make sense as the basis for the great-flood story. But the Euphrates flooded many times, and not being a rare occurrence, such floods would be unlikely to inspire an extraordinary story. The Nile flooded almost every year, and Egypt does not have a deluge story in its heritage. But in the biblical and other deluge stories, all or part of the flood is described as coming from the sea. The relevant verse from the Bible is in Genesis 7:11: “In the six hundredth year of Noah’s life, . . . were all the fountains of the great deep broken up, and the windows of heaven were opened.” Here “great deep” means the sea, and the “fountains” are the waters from the sea that contributed to the flood along with the rain. In the Bible, and in the other deluge stories, Noah’s Ark was not carried toward the Persian Gulf, as would have been the case with a river flood, but instead was carried to the north toward Armenia, as would be the case with water from the sea inundating the land.19 Some biblical scholars equated the “fountains of the great deep” with subterranean waters coming from the deepest part of the sea, perhaps released by an earthquake. But neither they nor the authors of Genesis understood that winds can push the waters from the sea onto the land (the storm surge), which is a much better explanation for why such a vast area was flooded. A tropical cyclone in the Persian Gulf would of course bring rain, perhaps many days’ rain, but it would be the wind-produced storm surge that would cause the flooding, as we saw in Bengal in 1864 and as we will see in more examples in this chapter and the next.
The reference to the flood coming from the sea is more explicit in nonbiblical versions of the deluge story, and perhaps there was even some understanding of the wind’s role. For example, in the Babylonian story, which is part of the Epic of Gilgamesh and was originally found on the eleventh of twelve clay tablets pieced together by George Smith in 1872, we have this description: “For six days and nights the wind blew, and the deluge and the tempest overwhelmed the land. When the seventh day drew nigh, then ceased the tempest and the deluge and the storm, which had fought like a host. Then the sea grew quiet, it went down; the hurricane and the deluge ceased.”20 The Babylonian Noah goes on to say, “I looked upon the world, and behold all was sea.” If a large area of low-lying land is covered by the sea, the flooding can reach to the horizon, and thus it would appear to cover the world.
The first author to hypothesize that the deluge came from the sea was Eduard Suess in 1885, but to explain the sea rushing in to cover the land, he felt it necessary to propose not only a large storm but also an earthquake-produced tsunami occurring at the same time.21 However, a storm surge can cause greater flooding than a tsunami. The flooding caused by a tsunami, as destructive as it can be when it first happens, does not last long, but the flooding caused by a large and lengthy storm can cover the land for days. What would be required is a huge tropical cyclone developing over the Arabian Sea and then moving up the Persian Gulf.22 Large tropical cyclones are extremely rare in this region, but they have occurred, and that rarity makes each of them a noteworthy event. Recently, on June 3, 2007, Cyclone Gonu reached Category 5 status with 160-mile-per-hour winds and became the most intense cyclone on record in the Arabian Sea. It hit Oman, at the entrance to the Persian Gulf, only the third time in twelve centuries that a tropical cyclone made landfall there, the other two occurring in 865 and 1890. Gonu’s storm surge caused flooding in Oman and in the United Arab Emirates. As powerful as Gonu was, it could not get far into the Persian Gulf because of the narrow entrance. The northern Arabian Sea narrows down into the Gulf of Oman, which is connected to the Persian Gulf by the very narrow Strait of Hormuz, only thirty miles wide. Gonu was weakened by the land and barely made it into the Persian Gulf. However, four thousand years ago sea level was higher in this region than it is today, and it is likely that the entrance to the Persian Gulf was wider.
Insurance companies often talk about the so-called hundred-year storm—the really big storm that happens on average once every hundred years. But is it possible that around four thousand years ago a thousand-year storm made it into and up the Persian Gulf to the mouth of the Euphrates? Its storm surge would have catastrophically washed over the low-lying lands of the Euphrates valley, producing a great flood that would in the following centuries grow into more than a legend, a flood that some would come to believe covered the world, except for a mountaintop on which an ark finally landed.
Ancient documents, of course, whether religious or historical, mention only floods, not the tropical cyclones that cause the storm surges that produce those floods. It is not until the fifth century AD, according to the earliest known written evidence, that someone recognized tropical cyclones as a special type of violent wind storm that came in from the sea to destructively flood the land. People living along the Pacific coast of southern China called this type of storm jufeng,23 which they described as “a wind (or storm) that comes in all four directions,”24 an apt description of a cyclone’s rotating wind system by someone who did not know that the wind was rotary. In the Northern Hemisphere a cyclone rotates counterclockwise, so that north of its eye the winds blow from the east.25 West of the eye the wind blows from the north; south of the eye, from the west; and east of the eye, from the south. As a tropical cyclone moves through an area, an observer will therefore see different wind directions at different times.
Because of the violent floods they produced, there was a need to predict when a jufeng would strike the coast. The earliest methods were, of course, not scientific, one common Chinese guidance being that one knows when a jufeng is approaching because “before it comes, roosters and dogs are silent for three days.”26 In later documents jufeng was replaced by the more descriptive da feng yu jia hai chao (“strong storm driving [a] sea surge”), which are the earliest written references to a powerful storm surge like the one described centuries later by the British in the Bay of Bengal. The oldest known historical document that describes landfall of a jufeng on the Chinese coast is Jin Tang Shu (Old History of Tang Dynasty), published in AD 816, in which the storm surge produced by a jufeng damaged the city wall of Mizhou.27 By the end of the ninth century, ideas on how to predict a jufeng and its storm surge sounded slightly more scientific. Some people believed that a preparatory wind (called a lingfeng) would occur before the arrival of a jufeng.28 Others thought that a jufeng would come when “among summer and autumn, clouds sometimes appear to be gloomy but with light like rainbow.” These warning signs were called jumu (“the source of jufeng”), and it was written that “sailors always watch this so as to take the necessary precautions.” They also recognized the important fact that a storm surge was most dangerous when it arrived at high tide.29 Beginning with the Song Dynasty (960–1279) the central imperial government kept official records of jufeng landfalls and their storm surges, including casualties and property losses.
The Japanese also experienced the destruction of tropical cyclones and their accompanying storm surges, but they had a different word for a cyclone, a name that came into use after one of the most crucial events in their history. In November 1274, Japan was invaded by Kublai Khan, the emperor of Mongolia and the grandson of Genghis Khan. He had a fleet of a thousand Korean ships and forty thousand Mongolian, Korean, and Chinese troops (he had already conquered Korea and northern China). Miraculously, however, his invading fleet was decimated by the high winds, large waves, and high storm surges of a tropical cyclone. The Japanese attributed the great storm and their salvation to three deities, and from that point on they referred to a large tropical cyclone as a kamikaze, “divine wind.”30 Five years later Kublai conquered southern China, ending the Song Dynasty and gaining additional resources for a second invasion of Japan. In August 1281, now with a fleet of 4,000 ships and 150,000 men, he again attacked. Incredibly, another tropical cyclone arrived just at the right time to once again destroy Kublai’s fleet and save Japan again. That was more than enough to solidify kamikaze in the Japanese vernacular.
The only other people in the world at that time who had some understanding of tropical cyclones and the storm surges they produced were the native tribes living in and around the Caribbean Sea. When Europeans arrived at those shores, they found that the locals spoke of a furacane or a huracán (there were many variations of the word), apparently named after the local god of the winds.31 Christopher Columbus learned of this after experiencing the high winds and rising sea of a hurricane while on an island in the West Indies in June 1495 during his second voyage to the New World. The Caribbean islanders, as well as the Mayans of the Yucatán, may have been the first to understand that a hurricane was a storm with rotating winds. The Mayans’ wind god Huracán was frequently portrayed as a head with two arms spiraling out from its sides.32 These spiral arms were usually in a direction that could imply a counterclockwise direction (the direction that hurricanes rotate in the Northern Hemisphere), and they looked incredibly like today’s internationally recognized symbol for a tropical cyclone.33
From the time of Columbus on, there is a long recorded history of hurricanes and their storm surges in the Caribbean, in the Gulf of Mexico, and along the Atlantic coast of North America.34 European explorers also encountered hurricanes in other regions of the world, though they often referred to them using their local names, which in the western Pacific was typhoon, that term having replaced jufeng as the word for tropical cyclone.35 Still another word often used for a hurricane or a typhoon was tempest, although it was sometimes applied to any big storm.36 Cyclone originated much later than hurricane or typhoon or tempest. In an attempt to find a universally accepted term, the word was invented in 1844 by an Englishman, Henry Piddington, President of Marine Courts of Enquiry in Calcutta, of whom we will learn more later.37
The strong winds that generate a storm surge, however, do not need to come from a tropical cyclone. Away from the tropics, especially along coasts in the northern regions of the Atlantic and Pacific Oceans, storm surges are frequently generated by the strong winds of weather systems that we call extratropical cyclones (or extratropical storms). Extratropical cyclones usually are not as violent as tropical cyclones, but they cover a much larger geographical area. The northeasters (or nor’easters) that strike New England are a type of extratropical cyclone, and the violent gales from the North Sea that strike the coasts of Great Britain and the Netherlands are the winds of extratropical cyclones. These storms are typically strongest in the winter (unlike tropical cyclones, which typically occur in late summer and autumn). They also have low-pressure centers (weaker than a hurricane’s), but these centers are cold rather than warm, as with a hurricane. Their winds also rotate around their center in a counterclockwise direction (in the Northern Hemisphere, but clockwise in the Southern Hemisphere) but are usually somewhat weaker, though still strong enough to produce dangerous storm surges. The Atlantic Coast of the United States has the unfortunate privilege of being assaulted by both tropical cyclones (hurricanes) and extratropical cyclones (northeasters). Hurricanes generate higher storm surges, but storm surges from northeasters can cause more property damage because they cover a much larger geographical area.
Europeans had no real experience with tropical cyclones and the storm surges they cause until the fifteenth century, when they began exploring the world.38 By this time, however, they had had many centuries of experience with huge floods from storm surges caused by the gales of extratropical cyclones—centuries of experience, but no idea how to predict when the next gale and the next flood would occur. Without that prediction capability, the best they could do was try to build coastal defenses to be ready for the day when a really large storm surge would wash over their lands. The most vulnerable coastal regions of Europe were the Low Countries—the Netherlands, western Germany, Denmark, Belgium, and northern France. Documents from Roman times describe destruction by storm surges produced by violent North Sea gales. In AD 15 Tacitus described how a storm-surge-caused flood swept over two Roman legions.39 Pliny the Elder had also reported on catastrophic floods, noting that the German people lived on earthen hills they constructed to rise above the highest flood levels they expected to see.40
This was one of the earliest human engineering responses against the destructive power of storm surges, but it was just the beginning. By the tenth century some coastal dwellers had begun building embankments and dikes to keep the sea completely away from their homes and farmlands.41 Then they went further, and after centuries of storm surges eroding their land, they began to take back some of that land. They built dikes around parcels of marshland, cutting them off from the sea, and then drained them to become dry land on which they could live and farm. These tracts of fertile land reclaimed from the sea were called polders.42 Major progress in creating and maintaining polders by the Dutch and their Frisian cousins to the north in Germany and Denmark came when they began using windmills to pump out the water, and soon thereafter windmills covered the landscape.
In spite of the success that windmill power had brought them, there remained a constant battle against the sea, maintaining their dikes against the destruction caused by every storm surge directed at them by North Sea gales. No matter how strong and how high they built their dikes, eventually a storm surge would be high enough and powerful enough to cause breaks in them and, once there were breaks, to scour out huge holes and tear them down. The mightiest of extratropical storms from the North Sea were given names, often from the nearest religious holiday, and became legends. But the lives they took and the villages they swept away were not myths, and to coastal residents the threat was very real and something for which they were always preparing.
One of those legendary floods was the Grosse Männdrenke (“Great Drowning of Men”) of 1362. On January 16 the storm surge from a North Sea gale washed away at least half the population of the island of Strand, off the coast of North Friesland in northern Germany, along with many tens of thousands of people in the coastal regions of the Netherlands and Denmark. Since January 16 was the feast day of St. Marcellus, this disaster was also called the Second Saint Marcellus Flood (the “second” designation because back in 1219 on the same day a North Sea storm had caused the First Saint Marcellus Flood, its storm surge drowning an estimated 36,000 people). To the north of Strand in Denmark sixty parishes were swept out of existence; to the south of Strand in Holland the storm surge had further opened the Zuider Zee to the sea; and to the west of Strand, across the North Sea in Yorkshire, England, the port of Ravener-Odd was destroyed. On the island of Strand the wealthy port of Rungholt disappeared into the sea, never to be seen again. Rungholt eventually obtained a “lost city” mythical status, with local mariners claiming they could hear its church bells ringing when they sailed over the waters covering the ruins of the sunken city. Accounts of the catastrophe had interpreted the storm surge as God’s wrath incurred by the people’s sins and blasphemy and the decay of morality in Rungholt. Only a preacher and two virgins were said to have survived.43 In England it was also supposed to have been the wrath of God that destroyed the port of Ravener-Odd, because of their piracies and other wicked deeds.
In the centuries following 1362 the dikes had been rebuilt, and the Frisians had again begun building polders and reclaiming land from the sea. In 1630 Duke Friedrich III hired a Dutchman known far and wide for his techniques in building dikes, creating polders, and using windmills to pump out water for more efficient land reclamation. He was born Jan Adriaanszoon, but because of his business, he had given himself the name Leeghwater, meaning “empty water.”44 Leeghwater lived in the village of Dagebüll on the mainland across from the island of Strand while he supervised creation of new polders. In 1633 his workers had closed the last gap in the dike around the Bottschlotter polder, and since then they had been damming the future Kleiseer polder. The duke himself had inspected the work. But on October 11, 1634, those four years of work were about to be undone in one night, for a southwesterly storm from the North Sea was driving a great storm surge toward them. Leeghwater later wrote an account of what happened on that night.45
In the evening, Leeghwater wrote, he became concerned about the strong southwesterly winds that had begun to blow, and this led him to return to his house, which sat on a dike eleven feet above ground level. By the middle of the night a storm surge had raised the water level high enough that wind waves riding on top of the storm surge smashed against the dike, sending spray onto the leaky roof. Lying in his bed, Leeghwater’s son felt water dripping on his face. With winds howling and water almost over the dike, Leeghwater and his son fled to the safety of the dike master’s mansion on higher ground. The winds changed to northwesterly, and the storm surge raised the water level so high that waves smashed in a door on the west side of the mansion, the water extinguishing the fire in the fireplace and filling Leeghwater’s kneeboots with seawater. In his account, Leeghwater described his sad feelings when his son asked him, “Oh father, shall we die here?” At the north end of the mansion the water eroded the soil to a depth of a man’s height, causing the floor and the hallway of the house to begin to break apart. It looked like the mansion with all its inhabitants would be washed over the dike into the raging sea, but somehow it survived.
The next morning Leeghwater saw that all the houses and tents that had been below them were washed away with all the people inside, including his master carpenter and his foreman and their families. Sea dikes that had been there for a hundred years were all destroyed. On the island of Strand only four or five strongly built parish churches remained from the twenty-four that had been there. He estimated that seven or eight thousand people drowned, including nine preachers. His own house on the dike was gone. In its place he found a large seagoing vessel sitting there. Several ships were also found resting on the highest streets in the nearby village of Husum. The storm surge washed away half the island of Strand.46 Later calculations showed that of the Strand’s nine thousand inhabitants, sixty-four hundred died, and many thousands died elsewhere in North Friesland. At least fifty-nine thousand head of livestock were lost.47 With the dikes destroyed, the agricultural fields in the polders were now covered with saltwater.48
Figure 3.1 “Die erschreckliche Wasser-Fluth” (“the terrible flood waters”), an etching of the destruction caused by the 1634 storm surge along the coast of North Friesland, Germany. (From Eberhard Happel’s “Greatest Curiosities of the World,” published in 1683)
By 1743 there was still almost nothing understood about the weather or its effects on the sea, and thus almost nothing was understood about how storm surges were produced. There have been many failed attempts to discover some correlation between patterns that people thought they saw in the weather or the ocean and the easily observable patterns in the movements of the moon, the stars, and the planets in the night sky. Scientists and theologians alike saw these predictable astronomical movements as proof that the world they lived in was an orderly, logical, and divine world. But astronomy was of no help in predicting the weather (except for the changing seasons) or in predicting movements of the ocean (except for the tides). Even the tides could not be predicted as accurately as an eclipse of the moon, which scientists could calculate down to the minute. And, as it turns out, it would be an eclipse predicted to occur exactly at 8:30 P.M. on October 21, 1743, in Philadelphia that would stimulate Benjamin Franklin to take the first big step toward understanding the wind storms that produce storm surges.
More precisely, Franklin’s thinking would be stimulated by the bad weather that prevented him from observing that eclipse, to which he had eagerly looked forward. At his home in Philadelphia the moon had been hidden by the thick clouds and heavy rain of a ferocious storm, but Franklin learned, much to his surprise, that the eclipse had been observable in Boston because the storm had begun there at a later hour. His brother Thomas, who was in Boston, said the storm did not start there until two and a half hours later, at nearly 11:00 P.M. Franklin later wrote in a letter, “This puzzled me, because . . . being a northeast storm, I imagined it must have begun rather sooner in places farther to the northeastward than it did in Philadelphia.”49 Then he learned that the storm had begun even earlier in Virginia than it had in Philadelphia. In another letter he wrote, “The storm did a great deal of damage all along the coast, for we had accounts of it in the newspapers from Boston, Newport, New York, Maryland, and Virginia.”50 In Boston a large storm surge had flooded the streets.
Franklin became the first person to realize that a storm was a moving system of winds and that it moved in a direction that was not necessarily the same as the direction of the winds themselves. He wrote, “Though the course of the wind is from northeast to southwest, yet the course of the storm is from southwest to northeast; the air is in violent motion in Virginia before it moves to Connecticut, and in Connecticut before it moves to Cape Sable [Nova Scotia], etc.”51 Franklin explained this with an analogy of a chimney over a fire. “Immediately the air in the chimney, being rarified by the fire, rises; the air next to the chimney flows in to supply its place, moving towards the chimney; and, in consequence, the rest of the air successively, quite back to the door [the source of cold air from the outside].”52 He envisioned warm air rising over the Gulf of Mexico and cooler air from the northeast flowing in to replace it, this airflow beginning first near the Gulf, then a little farther away (for example, Philadelphia), and then still farther away (for example, Boston). This first, still very incomplete, explanation of a moving storm system might have been used to predict winds at one location based on winds at another location, but in Franklin’s time, communication was not nearly fast enough to take advantage of his insight. Franklin’s growing understanding of storms and the difficulty in predicting them did not, however, stop him from putting weather predictions in Poor Richard’s Almanack, if only to keep up with the numerous competing almanacs of that time. We now see as absurd the idea of predicting weather a full year in advance, but all the Colonial almanacs did that, and at least Franklin, with his usual good humor, made fun of his weather predictions, realizing that, unlike his tide predictions, they had no astronomical basis.
Franklin does not seem to have ever suggested that this October 1743 storm might have had a rotating motion. He never knew that it was an extratropical cyclone, with a calm center over the ocean and air moving counterclockwise around it, which is why the winds along the coast came from the northeast. Even though Franklin had been very interested in and written much about waterspouts and whirlwinds (tornados),53 those narrow rotating wind systems never inspired him to wonder whether, for example, a hurricane might also rotate, though on a much grander scale. However, others had been inspired to speculate. Mariners had known for centuries that with hurricanes and typhoons winds changed direction, often moving around the entire compass over a fairly short time, and that sometimes the winds stopped completely for a short while. A few recognized this as an indication that the air was rotating around a calm center, the first probably being Bernhard Varenius, a German geographer who in 1650 had obtained much information from Dutch navigators.54 In 1698 Captain Langford of England’s East India Company wrote about five hurricanes in the Caribbean Sea and referred to them as “Whirl-Winds.”55 A hundred years later, in 1801, Colonel James Capper wrote, “All circumstances properly considered, . . . positively prove them [hurricanes] to be whirlwinds.”56
It would not be until 1831, however, that someone would use meteorological observations to demonstrate the rotation of a hurricane and thus lay a more scientific basis for the study of storms. It took a major hurricane to provide those data. The data came from the Hurricane of 1821, the only hurricane in recorded history whose eye passed over New York City,57 arriving there on the evening of September 3. Its storm surge caused a thirteen-foot rise in the water in only an hour, flooding the lower end of Manhattan up to Canal Street. The waters of the Hudson and the East rivers joined to cover the sidewalks of New York. But New Yorkers were lucky; the hurricane hit at low tide. One can only imagine the destruction if it had been high tide. Two days earlier while to the east of Florida the hurricane had been a Category 5, but after passing over land several times it had been reduced to maybe a Category 2 by the time it hit New York City.
But the most important thing about this hurricane was the insight it provided William Redfield after it had passed through Connecticut and Massachusetts. Redfield was a saddle maker turned steamboat captain and a self-taught amateur scientist. He was walking through the woods with his son from their home in Middletown, Connecticut, to northwestern Massachusetts and the home of the family of his wife, who had just died giving birth. In spite of his great sadness, he noticed that all the “fruit trees, corn, etc were uniformly prostrated to the north-west” in Connecticut, but when he reached Massachusetts, he noticed that the trees and corn “were uniformly prostrated towards the south-east.” Ten years later Redfield would publish a scientific paper in which he used this information (plus wind data he acquired from all over those two states as well from states along the Atlantic Coast) to demonstrate that “this storm was exhibited in the form of a great whirlwind.”58 That paper thrust him into the scientific limelight and also into what was later called the “American storm controversy.”
This “controversy” was an ongoing debate that began when James Espy, a scientist at the Franklin Institute in Philadelphia, put forth a different theory on hurricanes and storms, one that said the air did not rotate around a quiet center (the eye) but instead the air rushes in from all directions directly toward a low-pressure center. This was similar to Franklin’s suggestion a century before, except that Espy added to Franklin’s analogy of heated air moving up a chimney the important idea that the updraft in the center of a hurricane is stronger if moist air is involved. He used the concept of latent heat, which is the heat required to turn a liquid into gas (or the heat released when a gas condenses into liquid). Espy realized that water vapor is lighter than dry air and that, as moist air rises and expands, the latent heat released as the water vapor condenses helps the convection to continue longer.59 Thus, warm, moist air contributes more to convection in a hurricane than does dry air, which is one reason hurricanes form over warm oceans. This was an important contribution to meteorology, but unfortunately Espy got the wind direction wrong because he did not include the effect of the Earth’s rotation.60 The debate became national, with scientists in New York supporting Redfield and scientists in Philadelphia supporting Espy. Then it became an international debate when scientists in England supported Redfield, but scientists in France supported Espy. The issue was finally cleared up in 1856 in a paper by William Ferrel, who recognized that Redfield and Espy each had part of the answer (as so often happens).61
One of Redfield’s supporters was Henry Piddington, the British scientist in India who had coined the word cyclone in 1844. He wrote forty memoirs and books about cyclones in the Indian Ocean and China Sea, finding support everywhere for Redfield’s proposal that cyclones had winds that blow in large circular motions around a quiet center. But more important, Piddington was the first to write about the dangers of the cyclone’s storm surge, which he called a “storm wave.” He had written, “There really exists an actual wave or elevation of the sea, . . . which rolls in upon the land like a huge wall of water, as such a supposed wave should do, causing of course dreadful inundations.”62 Piddington had seen firsthand the havoc that a storm surge could wreak and the death it could bring in India and other low-lying lands around the Bay of Bengal.
At this point, we should make clear the meanings of the different terms used for the variation in the height of the sea’s surface, including storm surge, for there has often been confusion, especially in the popular press. The term water level is the most general term, meaning the height of the sea’s surface, but after averaging out the rapid surface oscillations due to wind waves (which usually have periods from a couple of seconds to about twenty seconds; see Chapter 5). Scientists define a storm surge (called a storm wave by Piddington and a sea surge by others) as a change in water level along the shore caused by winds, and to a lesser extent by changes in atmospheric pressure. Scientists use this term even if the winds are not strong enough to be categorized as a storm. The storm surge has sometimes been called a storm tide, but that term is more correctly used to mean the total water level change, namely, the storm surge plus astronomical tide. Here we put the word astronomical in front of tide because tide has often been used to mean simply a change in water level, including the effect of the wind, even though scientifically that word should only be used to refer to changes in water level due to the effects of the moon and the sun (as we talked about in Chapter 1). Others refer to storm surge as a meteorological tide, and although this still uses tide to mean a water level change, it at least says that the change in water level is of meteorological origin, namely, from the effects of winds and changing atmospheric pressure. The storm surge moves toward and sometimes onto the land as a very long wave, which steepens when it moves into shallow water. This long wave has sometimes been erroneously referred to as a tidal wave. To further add to the confusion, tidal wave has been often erroneously used for tsunami, which is the very long wave caused by an earthquake or volcanic eruption (as we will talk about in Chapter 7). Even today, especially in newspaper accounts, the terms tide and tidal wave are often misused, as is sea level. The term sea level implies an averaging out of all water level oscillations, including the tide and storm surge. It is used when we are talking about very slow long-term changes. These longer-term sea levels (usually yearly sea levels) are used in El Niño and climate change studies (see Chapter 10). Researchers studying sea level rise due to global warming try to average out all other oscillations that might bias the calculation of the trend, that trend hopefully only being determined by very slow changes in the heat in the upper ocean and the amount of melted land ice entering the sea.
For Piddington, the destructive power of a storm surge was first dramatically illustrated at Coringa on the Bay of Bengal coast of India in December 1789. Coringa and its 20,000 inhabitants disappeared in a single day after being hit by a succession of three great storm surges.63 Fifty years later another 20,000 people died when the rebuilt town was assaulted by another storm surge. After witnessing so much destruction and loss of life caused by the flooding from these and other storm surges, Piddington became very sensitive to potential vulnerabilities at coastal locations. Although as yet in no position to predict when a storm surge would strike a coast, he believed he knew enough to predict which stretches of coast and which harbors would be most seriously affected when a storm surge finally came. In 1853 Piddington was worried about the vulnerability of a new port that was proposed for the Mutlah River as an eventual replacement for the Port of Calcutta (because someone believed the Hooghly River was silting in).64 He sent an open letter to Lord Dalhousie, the Governor-General of India, about the proposed Port Canning, explaining how storm surges could flood it. He wrote, “Everyone must be prepared to see the day when in the midst of the horrors of a hurricane they will find a terrific mass of salt water rolling in or rising upon them with such rapidity that in a few minutes the whole settlement will be inundated to a depth of from five to eighteen feet of water.”65 Lord Dalhousie and others ignored his warning and built Port Canning on the Mutlah. On November 2, 1867 (nine years after Piddington’s death), a cyclone produced a storm surge that did just what Piddington had predicted, passing “over the town with fearful violence.”66 At the same time a storm surge in the Hooghly River did no damage to the Port of Calcutta. Five years later Port Canning was abandoned.
Although Piddington was best known by mariners who used his Sailor’s Horn-Book for the Law of Storms as a guide for avoiding the dangers of the eye of a tropical cyclone when at sea,67 he also had ideas about predicting storm surges from cyclones making landfall. Though the science was at that point incapable of such prediction, he suggested as early as 1842 that telegraphs might provide storm surge warnings.68 A prediction of the time of arrival of a cyclone and its accompanying storm surge at certain coastal locations might be possible, he thought, if real-time data via telegraph were received from locations where the cyclone had already been. Piddington hoped that “our children may see this done.”
But Piddington himself lived to see real-time telegraph capability enabled, though not in India, nor along the southern coast of China, where he thought tropical cyclone patterns were conducive to such a warning system. The first system was built in the United States and was not used for tropical cyclones. By 1850 Joseph Henry, first head of the Smithsonian Institution in Washington, DC, had established a network of telegraph weather stations across the United States, which were used to provide weather warnings.69 The huge map in the lobby of the Smithsonian showed in almost real time the weather conditions across the country.70 By watching this map over time, Henry, and many interested onlookers, could clearly see the eastward or northeastward movement of storms, as Franklin had first suggested, and from that movement he could estimate where each storm was headed. Eventually a storm would reach the Atlantic Ocean, where its winds might generate a storm surge along the coast, and it would be possible to make a rough prediction of its size and timing. Unfortunately, the Civil War and a fire at the Smithsonian put an end to the telegraph network. It would not be until the 1870s that another telegraph weather network would be created in the United States, this time run by the U.S. Army Signal Service.
In 1860, two years after Piddington died, a telegraph network of coastal observers was begun in Britain under the direction of Robert FitzRoy, the first director of Britain’s first Meteorological Department.71 Being a Navy captain, later an admiral, FitzRoy believed that coastal areas were most in need of storm warnings because of storm-wave-caused floods and the threat to mariners heading to sea in their boats. Two years earlier he had begun to distribute specially built barometers to dozens of fishing villages, initially in Scotland. He used telegraphs to receive meteorological data from twenty-two villages. In February 1861 he began to send them back predictions, first storm-warning signals and then daily weather forecasts (a phrase coined by FitzRoy). These forecasts were calculated using all the weather information he received by telegraph, and was based on an understanding of the rotary nature of extratropical cyclones (that understanding having been advanced by his careful analysis of the Royal Charter Storm in October 1859, which sank 343 ships, including the Royal Charter).
But FitzRoy’s weather forecasts were not appreciated by all, especially astro-meteorologists (astrologers, in actuality) who made a great deal of money selling almanacs with weather predictions erroneously based on movements of the moon, the sun, and the planets. Unfortunately FitzRoy was equally criticized by scientists in the Royal Society, who said that his practical science, which was meant to be used by everyone, was merely popular science that played into the hands of the astrologers. FitzRoy ended up killing himself on April 30, 1865, driven to that sad end, his wife believed, by anxieties over forecasts that failed and the criticisms aimed at him from seemingly all directions. His daily weather forecasts and his storm warnings were stopped the next year. The public reaction to the stoppage was so great that the storm warnings were brought back the following year, but it would be a decade before the daily weather forecasts were resumed.
As worthless as the predictions of the astro-meteorologists were, all it took was one perceived success to raise their stature in the minds of the public (and in their own minds as well) and thus to cause problems for real scientists who were trying to save lives with prediction methods based on ocean physics. Such a perceived success in predicting a storm and its destructive storm surge using an astro-meteorological technique occurred in October 1869 at the Bay of Fundy, with the Saxby Gale and its accompanying Saxby Tide (which more correctly could have been called the Saxby Storm Surge).72 The northern end of the Bay of Fundy was an unlikely place for a destructive storm surge. With an astronomical tidal range that can reach forty-eight feet, a storm surge arriving anytime except near high water will not flood the countryside, because the countryside is above the highest tidal high-water line. But the timing turned out to be just perfect on October 5, 1869. To begin with there was a perigean spring tide, which (as we saw in Chapter 1) means the moon was the closest it could be to the Earth and the sun and the moon were working together, it being new moon. And moving up the Atlantic Coast was a hurricane that proceeded up the west coast of the Gulf of Maine and then into the Bay of Fundy, a rare occurrence. That combination of perigean spring tide and six-foot storm surge produced the largest one-day tidal range in history, fifty-four feet at Burntcoast Head Lighthouse, Nova Scotia (although that record is somewhat misleading, since the people lived with forty-eight-foot astronomical tidal ranges, the world’s largest). Still, a six-foot storm surge can do a lot of damage. The storm tide flooded much of the land that the Canadians had reclaimed from salt marshes using dikes, much as the Dutch and Frisians had done in Europe, those dikes being overtopped. Salt water remained trapped behind the dikes for days after the storm.
Although the casualties due to the Saxby storm tide were less than in other disasters (about one hundred people died), the stories were no less tragic. A local paper, the Moncton Times, reported the story of the O’Brien family, caught by the storm surge. They “were awakened in the night to find their dwelling partly filled with water and all means of reaching dry land apparently cut off. In this dreadful emergency their only chance of escape seemed to be by means of a raft, and hastily constructing such a one as the drift timber within reach enabled him to make, he and his family got upon it and committed themselves to the mercy of the waves. The wind blew them across the river but unfortunately during the journey the raft parted and the four little boys drowned . . . in the midst of the fearful storm and thick darkness of Monday night.”73
What had given the Saxby Tide its name was that some believed it had been correctly predicted ten months earlier in England by Lieutenant Stephen Martin Saxby. Saxby was an acting Instructor of Engineering in the Royal Navy, who had his own system of weather prediction based on the moon.74 In 1868 Saxby had written a letter to the editor of The Standard in London, which was published on Christmas day. In that letter he wrote, “With regard to 1869, that at seven A.M. on October 5, . . . the new moon will be on the Earth’s equator when in perigee and nothing more threatening can, I say, occur without miracle.”75 On September 16, 1869, a second letter by Saxby was published in The Standard, in which he wrote that although his “warnings apply to all parts of the world; effects may be felt more in some places than in others.”76 Given the lack of specificity with regard to where the threatening event would take place, and given that at any moment somewhere in the world there would be storms, and also given that there would be a perigean spring tide on October 5, then it was a good bet that somewhere in the world there would be flooding caused by a storm surge. Saxby got lucky in the Bay of Fundy.77 On October 8, 1869, the editor of the Daily Morning News in Saint John wrote that he was inclined to believe that “Saxby is in this instance a true prophet,” but he also admitted that Saxby would instead be a “charlatan” if in the following days they did not hear of more lives lost, property destroyed, and vessels sunk all over the world.78 Of course, they never did.
It was then true and always will be true that to predict a storm surge, one must first be able to predict the storm. In the late 1800s meteorological science was still not advanced enough to develop a statistical or dynamical prediction technique for storms. The only method available was the use of real-time weather data from a telegraph observation system letting people know that a storm was heading in their direction—the methods of Henry and FitzRoy and the ideas of Franklin and Redfield still being the best approaches available. Such systems were begun again in the United States and in England, as well as in the Netherlands and France. These systems, being in the north, had to respond only to relatively slow-moving extratropical cyclones. The first successful telegraph network used for predicting hurricanes, and their very dangerous storm surges, was established in the Caribbean by Spanish Jesuits at Real Colegio de Belén in Havana, Cuba.79 Father Benito Vines, the director of Belén from 1870 to 1893, carried out an ongoing study of the characteristics of hurricanes in the Caribbean, publishing two books and becoming an internationally recognized expert. By 1888 Vines had established a telegraph meteorological observation network with seven regularly reporting stations (Trinidad, Barbados, Martinique, Antigua, Puerto Rico, Jamaica, and Santiago de Cuba) and with as many as thirteen other stations also reporting at times. Using real-time data from these stations and knowledge that he had gained from studying so many hurricanes over the years, Vines made the first hurricane forecasts, most very successfully. After Vines’s death, Father Lorenzo Gangoiti became the director and continued Vines’s program and its hurricane forecasting.
A national weather service with a telegraph weather network was started in the United States in January 1871, this time under the auspices of the Signal Corps of the U.S. Army. In 1891, after twenty years of disagreements between meteorologists and some military officers about the need for scientific research to improve weather forecasting, this weather service was transferred to the Agriculture Department and became known as the Weather Bureau. A scientist named Mark Harrington was selected to be its first civilian chief. However, a year later, the new Secretary of Agriculture, Julius Sterling Morton, brought in by the newly elected President Cleveland, was opposed to scientific research, even attacking scientists within the Weather Bureau, and preferred to ask a major in the Signal Corps for weather advice. Morton eventually convinced the President to fire Harrington on July 1, 1895, and he found a replacement to his liking within the Bureau, Willis Luther Moore, a man with more political ambition than scientific prowess.80 As we will see in the next chapter, this selection started a chain of events that five years later would lead to the greatest natural disaster, in terms of deaths, in U.S. history—a disaster caused by the large storm surge produced by a hurricane of which the residents of Galveston should have been warned, but were not.