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
