“But what is it?”
“A subterranean sea…”
Lily sailed them clear of the updraft, into calmer water.
Thandie said she had come up with the idea of deep subsurface oceans through luck. She was in the right place at the right time.
“It started with a study I came across from back in the noughties, where a couple of guys from UC San Diego went through a heap of old seismic signals. You understand that earthquakes generate waves that travel right through the structure of the Earth; you can track them and see how they are diffracted by the different density layers down there, and so on. What they found was a consistent weakening of the waves around a thousand kilometers deep, that’s in the Earth’s mantle, somewhere under Beijing. They showed that the muffling had to be caused by water, immense quantities of it, as much as the Arctic ocean maybe, trapped in porous mantle rock. And there are other theories about how there could be more water down there in other forms, whole oceans trapped a molecule at a time in the structure of certain minerals in the mantle rocks.”
“Subterranean seas.”
“Exactly.”
“So how does the water get there?”
“Well, maybe it’s a relic of Earth’s formation. The planet was born from a cloud of rock and ice, mostly water ice. It’s generally thought that most of the water and other volatiles were boiled off in the heat of formation, and the oceans we ended up with were delivered later by impacting comets. But planetary formation is a complex business. There’s no reason water couldn’t be trapped in the infall, as Earth coalesced.
“Or the water could be transported down there from the surface by tectonic processes. We know that happens in the present day. Here we are at a place where ocean-floor plates are created. There are corresponding places where they are destroyed-subduction zones, where the plates are dragged under one another, back down into the mantle. And when that happens, a lot of water and other material is hauled down with them.”
“So you knew about these deep reservoirs already. And when you needed a theoretical source for a sea-level rise-”
“I just plugged it in,” Thandie said with a grin. “The data fell into my lap. Then it was a case of finding the reservoirs. I figured that if the water is being released anywhere, why not here, at the mid-ocean ridges, where material is being dragged up from Earth’s interior?”
“Which is why we’re here.”
“Yes. I’ve got other data, charts of salinity and temperature anomalies and concentrations of various impurities, all of which pointed to some kind of ocean-floor event going on right here, along the Atlantic Ridge-and, I believe, along the lines of the other mid-ocean ridges too, though I’ve no good data to back that up. But an actual injection of water into the abyss is the smoking gun.”
“But why should this deep water be released now, after the Earth’s been around millions of years?”
“Billions, actually. Well, I hope to figure that out. But it isn’t that dramatic an event, on the planetary scale. Look-the Earth is like an egg, with the core the yolk, the mantle the white, and the crust the shell. To cover all the land surface would require an ocean three times the volume of the existing seas-but this would amount to less than one percent of Earth’s total volume. It would be an immense event for us, but only a little weeping of the white out onto the shell.”
“It sounds plausible to me,” Lily said. “But then I’m no scientist.”
“You’ve got more sense than most of the boneheads I’ve been duelling with on the IPCC.”
“Why can’t they accept what you say?”
“Because they’re all still bound up in generations-old arguments about climate change, which the new sea rise has nothing to do with, and which their existing models can’t predict. Because they’re in denial,” she snapped. “And that is not a pleasant state to be.”
“OK,” Lily said. “But I think I hope they’re right, and you’re wrong. No offense.”
“None taken. But I am right. I mean, now I’ve got the evidence.” Thandie was wide-eyed; as Lily had suspected, she hadn’t been expecting what they’d found today, and the implications were starting to sink in, perhaps for the first time. “I’m right. Oh, shit.”
The bathyscaphe shuddered and spun again, caught in the turbulence once more. “Time to go.” Lily reached for a joystick on the console before her. There was another shudder as electromagnets released the heavy iron ballast. Suddenly the Trieste was rising rapidly, still spinning, but as they ascended from the fountain the spinning was slowed by friction, and the water grew calmer.
Bit by bit, as they rose up, the sunlight penetrated the water’s murk.
28
December 2017
F rom Kristie Caistor’s scrapbook:
The director of Mississippi’s marine resources department lamented the failure of his scheme to cultivate mangroves in coastal areas of the state rendered uninhabitable by the flooding.
“It looked like the perfect way to make a constructive use of the abandoned land. Mangroves are kind of botanical amphibians. They can tolerate salt water, to a degree. They’re natural breakwaters that stabilize the land against erosion and flooding. They are a source of lumber, and pharmaceuticals. And they are refuges for wildlife-birds in the canopy, shellfish attached to the roots, alligators hunting at the water surface. They’re even terrific carbon sequestrators.
“But the sea is rising just too fast. Our mangroves are being drowned before they can grow, or do any good.
“We haven’t given up, we’re falling back is all, replanting further inland. I can assure the public that Mississippi’s mangrove dream is alive.”
29
February 2018
The flight into New York from Reykjavik was diverted. The pilot announced this was because of a storm system in the North Atlantic. They would fly north and swoop down over Canada as far as Montreal, and then track down the valley of the Hudson to the airport at Newburgh, which was as close to New York City as you could land now. Nathan had arranged further transportation to get them from there to Manhattan. Lily, in the window seat of the block of three she shared with Gary and Thandie, heard mutterings among the passengers that the “storm” was actually a hurricane gathering somewhere west of Iceland.
“But that’s ridiculous, isn’t it?” she asked. “You don’t get hurricanes this far north. And you don’t get hurricanes in February.”
Gary, on the far side, just shrugged.“We live in strange times, Lil.” He closed his eyes and rested his head back.
Thandie, in the center seat, didn’t respond at all. She had her eyes fixed on a screen on the seat back ahead of her, which showed sketchy handheld images of the Istanbul tsunami.
Lily gazed out of the window at a lid of cloud. She might have expected straight answers from climatologists. But the truth was they were all tired, she supposed, too tired even for a weather geek to care about a freak storm.
Nathan Lammockson’s call to Thandie to come to New York, to present her science conclusions to a subcommittee of the IPCC at the Freedom Tower, had been last-minute; that was the way things worked nowadays. The three of them had spent a frantic twenty-four hours packing up their material at Thingvellir, the inland Icelandic town the survey team had decamped to when the flooding at Reykjavik had become overwhelming. Thandie had been ready to go for a while with her presentation material, her graphics and analyses, her pages of mathematics; she had firmed up her conclusions months ago, it seemed to Lily. The grunt work had been preparing her confirmatory samples, slices of sea-bottom core preserved in Mylar sleeves and specialized refrigerated containers, and lots of tiny vials of sea water for the assembled boffins to pore over. They were weary even before they stepped on the plane.
The truth was everybody was worn out, Lily thought. The flooding continued, the relentless sea-level rise went on and on, patchy and uneven and punctuated by extreme events but relentless nonetheless. Piers had told her it had been a great psychological
shock in government circles when the rise had soared easily up through the ten-meter line, a limit that had been informally adopted as a worst-case upper bound by the UN and various relief agencies, derived from old climate-change forecasting models that now looked alarmingly out of date. Woods Hole reported the average rise to be thirteen meters globally since the start of the event in 2012, and continuing at an accelerating rate of three centimeters a day-an increase of nearly twelve more meters a year.
At the level of ordinary human lives, everything kept being mucked about. The pilot on this Airbus flight, for instance, needn’t have bothered telling his passengers they were being diverted; you expected it. With so many of the world’s major airports flooded, including hubs like Heathrow and JFK, airline routes and schedules were all over the place. Before she flew Lily had spoken to Amanda in her caravan park in the Chilterns. Amanda was assailed by increasingly odd weather, working from home as commuting to a drowned London was no longer feasible, and spending most of her free time queuing for water or persuading Benj and Kristie to keep attending school classes in a marquee. It wore you out, even if you weren’t in one of the disaster zones, like Karachi or Sydney or Florida or Louisiana or Sacramento, or, now, Istanbul.
Everybody on the planet was tired, Lily sometimes thought. And there was no end in sight.
The pilot announced they would fly south of Newburgh, bank over NewYork City itself, and then head north up the Hudson, so they would be making their final approach into the headwinds. As the plane made its turn over Long Island, heading west toward the city, Lily peered out of her window, picking out the distinctive shape of New York Bay. She wished she knew her geography a little better. She made out the inland sea that had developed out of Jamaica Bay; somewhere on its fringe was JFK airport, drowned, as indeed was La Guardia. At the mouth of the bay, at Rockaway Point, she saw a pale white line spanning the narrows, glistening under a blue-gray sheet of water: that was the levee the city authorities had thrown up to try to protect the bay and the airport, a barrier already overwhelmed. As the plane banked to the north Lily made out a second levee, this one between Brooklyn and Staten Island. But it too was drowned.
No fewer than four of these great levees had been thrown up in less than two years. The other two were to the west, across the Arthur Kill between Staten Island and New Jersey, and further east between Queens and the Bronx, spanning the East River under the Whitestone Bridge. It was a mighty system intended to save the vulnerable metropolitan areas from the then-expected rise of less than ten meters, a monumental effort. There hadn’t been time to compute the final cost before the rising sea had overwhelmed it all.
As the plane headed north Lily was able to glimpse the transformation of New York City itself. Great bites had been taken out of Jersey City and Brooklyn, the roofs of buildings sticking forlornly out of the water. Around the shore of Manhattan the flooding had made a more detailed, almost fractal nibbling. In general south Manhattan was lower than the north, and that was where the flooding was most extensive, but the pattern was lumpy, uneven; Manhattan was a hilly island. Whole swathes of the flooded areas showed fire damage. And even those buildings not damaged by fire would be mortally wounded, Lily knew from her own experience in London, their walls and floors rotten with fungi, their foundations undermined, their joints stressed. She was looking down at square kilometers of desolation, thousands of homes, factories, offices and shops that could never be made habitable again, even if the flood water receded tomorrow.
Leaving the city behind, the plane fled up the valley of the Hudson. The valley itself was flooded in places, and bore the scars of evacuation, small towns overwhelmed by shanties, the hillsides stripped of trees for firewood. A linear refugee camp had spread along both riverbanks, a litter of tents and cars that stretched almost as far as West Point. When the flooding began, the first instinct of many New Yorkers had been to head up the Hudson in search of higher ground. Some had made it as far as Connecticut and New Jersey before the military and city authorities had blockaded the freeways at West Point. All over the world it was like this, Lily knew, the governments bottling up populations in the threatened cities on the estuaries and coasts, trying to keep some kind of control, seeking solutions that would keep everybody fed and watered and sheltered.
And as the plane began its descent toward the hastily laid-down airstrip at Newburgh, a few kilometers north of West Point, Lily glimpsed the vast new development being opened up to the north, approaching the foothills of the Catskills. Acre upon acre of brown earth had been scraped clear of forest and foliage, and patterned with mosaics of blocky prefabricated housing and the uglier sprawl of industrial developments. Here was the city’s final solution, the levees and sea walls having failed: yet another tremendous project executed at huge cost and at enormous speed. New York was evacuating its essential functions, its industry and itself from the doomed environs of the bay and up onto higher ground. It was a remarkable translocation of millions of people, with a tearing-down and rebuilding of factories and power plants, houses and schools and hospitals. This was how a rich nation coped with such disaster, by building again, by continuing.
But there was an unevenness to the development, visible even from the air. You could see sprawling gated townships with villas and lawns and even the sky-blue gleam of swimming pools, surrounded by walls beyond which meaner communities of tents and tin shacks spread. Lily was learning the jargon, adopted from war and disaster zones around the world and now brought home: Green Zones for the rich, FEMA-villes for the not so rich. And she thought she saw tiny sparks in the country beyond the new settlement: gunfire, the sign of the ongoing war between residents and refugees, and government against survivalists.
Thandie still had her head down, staring into her screen.
“You ought to see this,” Lily murmured to her.“It’s amazing. A whole city on the move. A year ago, two, you’d never have dreamed you’d be seeing such a sight.”
“It’s all amazing,” Thandie said, her voice toneless. “All over the world.”
“You’re still looking at Istanbul?”
Thandie tipped the screen.“Actually I have to keep flipping channels. Most of the US stations are showing what’s going on in Sacramento. Or even Washington, DC, for Christ’s sake.”
At any other time, Lily thought, either of those incidents would have been a major story. Sacramento was an unfolding, unexpected disaster. Storm surges had forced Pacific waters tens of kilometers inland across the Sacramento river delta, wrecking the irrigation systems that fed farms that supplied fruit and vegetables to half the country. Then when flash floods overwhelmed the Folsom dam above Sacramento, the city found itself caught between river and sea water. Hastily reinforced levees failed. A quarter of a million people were in flight, in this one incident.
“But this, Istanbul, is bigger than that,” Thandie said. “Because it’s something new. The start of the next stage.”
Lily frowned; that sounded ominous. She peered at the screen. She saw a cityscape sprawling over hills and ravines, domes and minarets protruding from grimy flood waters, a fallen bridge, whole districts burning; too-familiar pictures, images that could have come from anywhere. “What am I looking at?”
“A view from one of the city’s tallest buildings. A bank tower. Itself disaster-proof, probably. Istanbul spans the Bosporus-yes? The strait where the Black Sea to the north connects with the Sea of Marmara to the south.” She tapped the screen, brought up an aerial view and traced a path. “This is the line of the North Anatolian fault, the place where the African tectonic plate is pushing north into the Eurasian. You can see it parallels the north Turkish coast and then passes under the Sea of Marmara.
“They knew a quake was coming. There have been eight Richter-seven-plus quakes in the last century, steadily marching along the fault line toward Istanbul. That’s why the rich have been building modern quake-proof developments on the hard rock on the Asian side of the strait, and the poor, millions of them, h
ave been throwing up shoddy illegal houses on the soft rock of the European side.” She passed her finger over the screen. “The quake itself knocked down ten thousand houses. The older buildings survived better than the modern, generally. I guess anything that has lasted a few centuries in a region like this is going to last a lot longer. Even the dome of the Hagia Sophia is intact.
“But the quake came under the Sea of Marmara, and that generated the tsunami, seven or eight meters high, which did a lot more damage when it hit the city. So now there’s yet another vast refugee flow-”
“Thandie-what ‘next stage’?”
Thandie looked up. Her eyes were hollow, unfocused, tired from staring too long at the screen. “Lily, as the oceans rise we’re going to see a shift of isostatic pressures. The sheer weight of the floodwater will depress the land it lies over-the way the glaciers of the Ice Age pushed the continental land down so hard it hasn’t finished rebounding yet. And those shifting pressures are going to stress the faults, the weak points.”
“Like the North Anatolian fault.”
“Yes. And hence the Istanbul tsunami.”
“But you can’t be sure that’s the cause.” She’d been around scientists enough the last few months, and indeed before that with Gary in Barcelona, to get a sense of how their minds worked. “It could be just coincidence. You said yourself that this has been a quake waiting to happen for decades.”
“Yes. It could be coincidence. Or the start of a new kind of response to the flooding, a tectonic response.”
“Terrific. And do you feel confident enough to say this to the IPCC?”
Thandie glanced out of the window, at fields and farmhouses and a glimpse of river that shot by as the plane made its final approach.“You’re right. I can’t be definitive. The IPCC is conservative. When they make their final report to the UN and the governments they’ll strike out anything that can’t be proven seven ways up. That’s what they did with the climate-change predictions, all those years. But I’ll flag it up even so.”
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