A couple of years ago David Gessner traveled the Atlantic Coast and pondered the research of Orrin Pilkey, one of the country’s leading scientists studying coastal geology. What would happen if a super-charged Atlantic hurricane struck the densely populated East Coast? Worrisome trends in the environment, industry, and population distribution are at the heart of The Tarball Chronicles, the book Gessner would later write. His speculation was prescient: Embodied in Hurricane Sandy, some of his fears are coming true.

Please take a moment to read this excerpt from The Tarball Chronicles. It describes how climate change is poised to vex the people of the Eastern Seaboard for years to come—unless we act swiftly and plan strategically.

From “Atlantis”:

I am not in the business of predicting the future, but I will say this: it’s only a matter of time until what happened to New Orleans during Katrina happens to another city. Miami is an obvious candidate, but there is another, even more high-profile city that is ripe for flooding. At the end of our tour of the Outer Banks, Orrin Pilkey said something that stuck in my head:

“Let’s say the seas really rise seven feet. That’s not a prediction, mind you, but a working figure I’ve now arrived at. If I were in charge of things that is the figure I would use. It’s smart to be ready for the worst. The official prediction now is a meter but I think it’s too conservative. I would act as if the seas would rise seven feet by 2100

“If sea level rise really does get to six or seven feet we aren’t going to be worrying about a few beach houses,” he continued. “We are going to be worrying about Manhattan and Boston.”

When I got home from our trip I wanted some confirmation or refutation of that seven-foot figure, which was the highest I had heard. I decided to go directly to the top and sent an e-mail to Jim Hansen, the head of NASA’s Goddard Institute for Space Studies. Two hours later Hansen wrote back:

That’s a good figure, in my opinion. If we stick to business-as-usual it will likely result in a sea level rise of about two meters, which is about seven feet. The catch is that if we hit two meters in the order of a century, it means we would be on the way—sea level rise would not stabilize at two meters.

Of course Hansen’s goal is to dramatize global warming, and there are a lot of other numbers floating around. The latest UN report by the Intergovernmental Panel on Climate Change (IPCC), signed by 2,500 scientists in 2007, predicted a potential rise of seven to twenty-three inches, but this prediction is dated by the fact that the IPCC did not consider the melting of ice caps in Antarctica and Greenland. Since then a chunk of Antarctic ice seven times the size of Manhattan has calved off from the Wilkins Ice Shelf, and the predictions have grown more dire.

A few months after my e-mail to Hansen, I talked Orrin into taking another trip with me. This time we traveled to an island of a different sort, not a barrier island but a chunk of glaciated bedrock, home, not to a few thousand people, but to eight million.

New York City had never felt more primal than it did that day. Orrin noted how the gridded streets would act as sluiceways leading water from the rivers into and through the city. We walked down into the subway and found a humid subterranean world. The subway tracks gleamed black, and the white wall tiles dripped sweat as the place radiated a steamy rain forest heat. I tried to imagine even more primal conditions: the tunnels filling with moving waters.

Most primal of all was Ground Zero, a name that takes on a whole different meaning when you realize how close it is to sea level. All those years after the attack and the scene still seemed chaotic. A car ramp led down into a chasm of gray cement walls and Porta-Potties and erector-set bridges and temporary worker trailers and staging and tattered American flags and piles of garbage. This was just about the lowest elevation in the whole city, land that had once been in the water and might be again. I imagined describing the particular configuration of land and water to a geographer, while stripping it of its specific famous and overpopulated locale. What, I would ask, would you call a great chasm less than five feet above sea level that is also less than a quarter mile from a rising body of water? Well, the geographer would answer, I know what I will soon call it: a lake.

In fact, geographers and scientists already have a name for this lower tip of Manhattan, a name that graphically suggests how it might fare in the face of sea level rise. The Basin, it is officially called. One of those scientists, Klaus Jacob, a Columbia geophysicist who is working on a Climate Change report for the city, has gone even further. He calls it the Bathtub. Some New Yorkers used this same name for the

excavated Ground Zero site itself, due to its tendency to fill up with water after rainstorms, but Jacob believes the name fits the whole of lower Manhattan.

My brain, like most of ours, tends to focus on the short term. The coffee and doughnuts that Orrin and I had for breakfast, for instance. But as we toured New York I tried to stretch my mind. Seven feet. It’s a bold, perhaps too-large number. But let’s say we accept the fact that Orrin Pilkey and Jim Hansen, who spend their lives studying this sort of thing, know more than we do, that their observations and calculations trump our gut feelings that it couldn’t happen, not here, not really. Let’s just assume, for the sake of argument, that when they say seven feet we should take them seriously. What would that actually mean?

What seven feet would mean in New York is that the Bathtub of lower Manhattan would fill to the brim. Streets would flood, water rushing down into subways that would turn into underground rivers. Standing there that day I felt an odd conflation of disasters. 9/11 melded with Katrina. Strange how our modes of apocalypse shift, like styles of clothes: terrorism, nuclear war, economic collapse. And yet Katrina signaled a shift in which nature itself began to play the role of the heavy. Nature, and of course us, the great manipulators of nature. What is sea level rise if not the result of our use of oil and other fossil fuels? It is all connected, both natural and un-.

I think of a trip I made to Belize, to a village called Monkey River Town, seven months after the towers fell. Everywhere people talked about the great tragedy that had struck the fall before, but they weren’t talking about September 11. The date they kept mentioning was October 9, the day that Hurricane Iris, a category-four storm, had slammed into the coast of southern Belize with winds in excess of 140 miles per hour, killing dozens and leaving 10,000 homeless.

Manhattan is safer than Belize, and safer than New Orleans, thanks to the cooler waters off its coasts, giving hurricanes less energy to feed off. But New York has seen its share of storms. In 1821 a category-four hurricane hit New York City directly, raising a storm surge of thirteen feet in an hour, cutting the island in half, and flooding the entire city. In 1938 the famous storm known as the Long Island Express hit the coast with a storm surge twenty-five to thirty-five feet high. Perhaps most relevant to today is Hurricane Donna, which struck New York on September 12, 1960 with ninety-mile-an-hour winds and five inches of rain. The images of Donna help one imagine the storms to come: people in lower Manhattan trudging through waist-deep water, others floating along in rowboats. The United States Landfalling Hurricane Probability Project predicts that there is an 89.9 percent probability that the New York/Long Island area will be hit with a category-three hurricane over the next fifty years. But the truth is that as sea levels rise it won’t even take a hurricane to flood lower Manhattan. A strong enough nor’easter will do the trick. That is why hurricane experts see New York, despite the relatively low odds of a category-four storm, as the country’s second most dangerous major city, behind only the hurricane bull’s-eye of Miami and just ahead of New Orleans. Consider that all three major New York airports, as well as the rail, and most obviously the subway, are less than ten feet above sea level, and storm surge predictions for a category-three hurricane top twenty feet in most locations. That puts JFK ten feet underwater.

There are all sorts of plans to prevent this, but they sound a lot like the usual plans to prevent weather and seas and winds. Boys with toys again. One plan involves building three large barriers at the Verrazano Narrows, Arthur Kill, and Throgs Neck, barriers that will theoretically shield Manhattan in the manner of the Eastern Scheldt barrier that protects the Netherlands. But beyond staggering costs is the question of their potential effectiveness. One man who questions how much good barriers would do is Klaus Jacob. Jacob, playing the Orrin Pilkey role in New York, is deeply skeptical about dikes and barriers; he thinks that barriers or walls will just give people a false sense of security. “The higher the defense, the deeper the floods,” he has written.

In fact, Jacob has already suggested the same notion to the residents of New Orleans. Not long after Katrina, he caused a stir by writing one of the first papers that proposed that it was foolish to rebuild New Orleans. The idea might have been politically controversial, but Jacob argued that it was also innately commonsensical given sea level rise and the fact that parts of New Orleans are actually ten feet under sea level. Why spend a hundred billion dollars to rebuild when the odds are it’s going to happen again fairly soon? He wrote: “Some of New Orleans could be transformed into a ‘floating city’ using platforms not unlike the oil platforms off-shore, or, over the short term, a city of boathouses, to allow floods to fill in the ‘bowl’ with fresh sediment.” New Orleans, he went on, would soon become an “American Venice.”

Which sounds nice in theory. But what if you happen to live here?

After my visit to the Ninth Ward, I drive out to Chalmette, a town that was completely submerged by Katrina. Locals talk of how the massive water tank blew off its great stem and bobbed around on the rising water like a giant beach ball. I stop to get gas and start talking to the guy who is sitting on the bench outside the service station. His name is Joe and his house was completely destroyed by Katrina. It wasn’t the first time. The same home had been destroyed by a hurricane in 1965.

“That was Hurricane Betsy and my little daughter was one month old. I remember it was ’65 because the next time my house got wiped out my little girl was forty.”

He shakes his head slowly.

“If it happens again I’m leaving and not coming back,” he says. We shake hands good-bye. But then as I start to walk back to my car he adds one more thing.

“Of course that’s what I said the last time.”

On the way back from Chalmette, I see a homemade sign that reads “Car repairs.”

I pull into a garage to ask about my shaky car. It’s a section of town called Araby, a name I begin to understand as I sit in the garage listening to Arabic music on a boom box while Ali, a smiley, chain-smoking mechanic, fiddles under my hood. His shop is not officially open for business yet, but he offers to fix the car for cheap, an idea that’s quite attractive to me. I sit there for over an hour while he unscrews one of the heads and replaces it with a new one, his cigarette resting on the edge of my engine. After a while he shuts the hood and slaps it. “You are good to go,” he says. After I pay him—“Cash only”—and pull out of his garage, the warning light no longer flashes and the car no longer bucks.

In the evening I tour the city with a local filmmaker and folklorist named Kevin McCaffrey. We pass gutted shopping centers that look like they could have been used as backdrops in Mad Max. I know why I’m thinking of the movie, of course. Again I feel like I’m living in the future. Or is it the past? Five years after Katrina and in some of the malls not a single shop has reopened.

“It’s not just the oil that we fear,” he says. “The basic math of the Louisiana coast is working against us. The ground is sinking and the water rising.”

Food is Kevin’s specialty. He talks about the oyster beds down in the bayou, how they have become less productive. His worry is that it isn’t just the oysters that are being lost, but local knowledge.

“The young men file for the same plot that was their grandaddy’s. But the coast has changed so much in just the last few years. The old plot may not be a productive plot. Why not put new beds in a new place as the coast moves? Or have they already lost the knowledge to know where to put the beds?”

The oil is a disaster for the oysters, but also for the culture here, since so much of that culture centers on food—“Food is New Orleans,” Kevin says—and so much of that food is seafood. In earlier years the Gulf spilled over with a great abundance and out of that abundance grew the food traditions of New Orleans, which hold the city together. The equation is simple: food is New Orleans and oil kills food.

For ourselves, we pass up fancier restaurants and head to a place called Frankie and Johnny’s. We eat a good greasy dinner (I have a fine chicken fried steak) and, after we have fully discussed the coming oily apocalypse, the talk turns to football. I’m getting used to this conversational mood shift, characteristic of my encounters here. Burned out on doom, we run to sports. Once again I’m impressed by how much the Saints mean to this beautiful, doomed city.

“Thank God the Saints won,” Kevin says. “But that isn’t going to save this place.”

A storm is coming, but the people at French 75 seem no more worried than Glennis was about the oil. After a day of exploring the city, I wander back to my new favorite bar for a nightcap. I sip a Daisy on my last night in New Orleans as the customers scoff at the notion that a puny tropical storm like Bonnie could scare people as tough and storm-scarred as they are. There is nervousness under their bravado, however, since you never really know with storms out in the Gulf. Especially when you have just come off the warmest six months on record.

During my recent visit with Kerry Emanuel, the MIT professor who described the “natural human ecology” of the coast, he educated me on these trends. Emanuel is one of the country’s leading authorities on the recent intensification of storms. If you were to read a so-called balanced account of this issue in the newspapers you might come away believing that the scientific jury is still out on whether or not our warmer waters lead to more intense storms. In fact, this is a little like saying the jury is still out on evolution versus intelligent design. The real split, Emanuel explained to me, was not in the scientific community, but between the scientists and the weather forecasters. He assured me that what common sense suggests is true: warmer waters lead to more violent storms.

People talk tough in French 75, but they all know that this will not be the season’s last storm. And as for the Big One, it’s only a matter of time.

“All that oil is out there somewhere,” says a man down the bar. “A storm would churn it up and send it raining down on us.”

I have no idea how feasible this is. This was one of the early legends of the spill. You heard it a lot down here, that there would be oil raining down on New Orleans. It sounds more like a biblical plague than science, and maybe that’s the point. Is fire from the sky next? A host of beetles? Nothing would surprise the citizenry of this town.

My mind has migrated to a strange place. I’m falling for this city, and I’m having a great time. Bring on the Daisies and the Cajun food. But at the same time a part of my brain is filling with thoughts of disaster. It’s not just the oil or Katrina. These simply seem a part of a larger series of disasters to come. Things fall apart, and they have, and are, at an alarming rate. I don’t really know how to respond to this since I am not, by nature, an apocalyptic thinker. But maybe I happen to be living, by pure bad luck, in apocalyptic times.

At the end of my long hike through New York City with Orrin Pilkey, he climbed in a cab and headed back to the airport while I walked south for a couple of miles to do something I hadn’t done since I was a kid. When I got to the Empire State Building I waited in line for well over an hour—first the line for tickets, then the line for the first elevator, then the line for the final ride to the top. But the wait was worth it. The weather was clear and the view was both startling and scary. How could human beings build anything so high? I snuck out within ten feet of the edge and looked toward downtown, toward the Basin, the Bathtub.

The city was laid out below me like a map. Back on the Outer Banks, Orrin pointed out the folly of having streets that ran from the ocean to the marsh side of the barrier islands, since during storms those streets could easily turn into inlets. New York’s streets would perform the same function, leading water from the Hudson to the East River, ushering the storm surge straight into and through the city, crisscrossing the place with water and helping flood the island.

It was hard for me to get my head around this picture of a drowning city. How can we not be a little skeptical? This is the way the world is, we think, the world we know, and this is the way the world will stay. To say that most of us are climate change skeptics is not to say that most of us doubt the work of science. What we are perhaps truly doubtful of is the ability to predict or believe in radical change. It’s simply not in our DNA.

From the Empire State Building I looked down and, tired of picturing what might be, I imagined what once was. Were I able to travel back in time, say a thousand years, the island below would have been crisscrossed with streams and spotted with marshes, not cross-sectioned by streets and studded with buildings. The site where the Trade Center towers once stood would have been well offshore to the east, submerged then as it might be again. The only human beings that inhabited the place would have most likely done so seasonally, the way most humans have always used the coast, taking advantage of summer’s abundance but wary of winter’s cold winds. The island itself, like all islands, once migrated, forming and reforming through storms and currents, though that was before buildings were shot down into it, like framing nails, to try to keep it still. But of course it won’t keep still. The human desire to pin things down won’t keep the place from changing: the island was once something else and soon enough will be again.

Up there, on top of the world, I found myself growing weary of apocalypse. Despite Orrin Pilkey’s energy and charm, I was still not yet entirely sold on the fact I so often hear repeated: that global warming and sea level rise will lead to our doom.

But then again, it didn’t hurt to play a little game of “what if.”

What if? It was easier to picture it from above: water filling the lowest areas first, pouring into the Trade Center site, cascading down the subway steps, using the cross streets to cut inland toward the island’s middle. Even with a mere .71-meter sea level rise by midcentury, the conservative number the city planners have settled on, New York faces obvious threats to its water supply, sewer, and wastewater systems, coastal erosion, and saltwater infiltration of aquifers and surface waters. Meanwhile, according to the United States Global Change Research Program’s assessment, “subway, road or rail tunnels or ventilation shafts will be at or below flood levels.”

And this was without a hurricane. There’s the rub. The fact that gets lost in the squabbling over numbers is that sea level doesn’t have to rise a single millimeter for a Katrina-like disaster to strike New York.

While I had spent the better part of the day trying to imagine this, the truth was that the word unimaginable worked pretty well in this instance. Eight million people on an island that is close to sea level with questionable means for evacuation. Experts can talk in a positive fashion about “solutions,” but the truth is that while sewage barriers are nice, the current strategy really comes down to being lucky. After all, isn’t it simply due to good fortune—a kind roll of the dice—that storms have veered in other directions and that a major storm hasn’t hit in at least a decade? We can create barriers for sewage plants—and by all means we should—but we can’t control what is uncontrollable. No one wants to hear it but the real conclusion of an honest climate change impact report would be pretty simple: keep your fingers crossed.

I pictured a storm barreling up the East Coast and then veering northeast, drawn into the funnel of the Verrazano Narrows through the Upper Bay and toward the Hudson and East rivers. Once there, it would send twenty-five-foot storm surges over Battery Park and wash over Ground Zero, filling the bathtub of lower Manhattan to the brim.

I am no prophet, and I certainly wasn’t saying this would happen. But there is no doubt that it could. Or it could do any number of other things, could veer slightly east and take out the Rockaways, for instance, or slam into Coney Island, once a healthy barrier island before its leeward marsh was artificially filled, where high-rise buildings now stand right next to the Atlantic. Or the storm could decide—orwhatever the storm equivalent of “decide” is—to skip New York entirely and head for Boston or Washington.

Like most of us, I could barely imagine this happening.

But that, I understood, had no impact on whether it would or wouldn’t.

Read another excerpt of The Tarball Chronicles: A Journey Beyond the Oiled Pelican and Into the Heart of the Gulf Oil Spill. Find more information about the book here.

Image by NASA Goddard Photo and Video, licensed under Creative Commons.