Stephen Baxter - Flood

Piers sighed. “You’re not going to get deep, are you?”

“Well, you have to face it, Piers. We spent five years in cellars. Now we’re in confinement again, and here we are, running around the walls. As if we’re testing the boundaries of our cage.”

“Or maybe we’re just trying to keep fit.”

“Kristie says we should have had more therapy when we came back from Barcelona.”

Piers snorted.“I seem to remember London was flooding at the time. It was hardly an opportune moment for long sessions on the couch, was it?”

“Maybe not, but-”

“It’s not us who have the flaws, Lily. It’s not us who are psychotic, however long we spent chained to radiators. It’s the world. The world is psychotic. I mean, is this how you imagined spending your old age? And besides, frankly, Lily, you’re one of the sanest people I know on this ship. If you’re going crazy, we’re all doomed.”

“Maybe so.” But it didn’t always feel as if she was so sane, not when she lay awake in her bunk in the small hours, alone in her head, listening to the deep groans of the ship’s hull as she forged endlessly over the deepening world ocean.

Looking back after seven months of the voyage, the first few days and weeks had been extraordinary.

The intense social life of upper-crust Project City had transplanted itself to the Ark, brittle, gossipy, somehow desperate, as if this was simply some exotic cruise. Four-course dinners had been served in the great restaurant every night, and Nathan’s pet refugee string quartet played in the verandah bar. Amanda would have been in her element in those early days, Lily thought sadly.

But that veneer of cruise-liner luxury hadn’t lasted. Lily had been able to keep her suite, but it was an awfully long time since anybody had come to fill up her mini-bar. In fact she now used it to keep her socks in. The always artificial barrier between “passengers” and “crew” had broken down in a farcical scene when Nathan had tried to discipline one of the kitchen staff for getting a passenger pregnant. They were all crew now, all of them had a job to do.

And as the relationship of the crew with each other had sorted itself out, so the internal functions of the ship had been reorganized. Nathan had ordered that a few areas be kept aside for recreation and exercise, like the promenade deck track, but others had been given over to vital functions like desalination.

One of the swimming pools was now being used as a mineral extraction area. Electrical currents were passed through sea water to make the minerals dissolved in it accrete out on metal mesh. The water was full of calcium carbonate, the relics of the shells of tiny sea creatures, which could be used to make a kind of concrete. And there was magnesium too, present at a concentration of a kilogram or so per ton of sea water. Nathan’s plan was to use these materials to maintain the fabric of the ship itself. Lily thought it was miraculous to see these substances appear out of nothing; she had had no idea that sea water itself was so rich.

Her own OTEC plant was an experiment in extracting another resource from the water: energy. “OTEC” stood for Ocean Thermal Energy Converter. There was a temperature difference of a few tens of degrees between the warm surface of the sea and the deeps where the temperature was only ever a few degrees above freezing; just as it was always dark down there, so it was cold. The idea of OTEC was to extract usable energy from this temperature difference. The floating raft topped a stalk that plunged more than a kilometer deep into the ocean. The warm surface water was cooled a little, the cold deep water warmed a little, and the flow of heat between them could be tapped. The temperature difference was greatest in the warmth of the tropics, which was where Nathan hoped to sail his Ark for most of the year.

There was a side effect, however, in mixing up the nutrient-rich deeper waters with the surface. Around the OTEC algae bloomed in a frenzy of feeding and breeding. These algae were harvested, especially a variety called spirulina, optimal crop plants with almost their whole substance being edible, nothing wasted on such fripperies as leaves or trunks or stalks. But the algal protein needed some heavy preparation before it became palatable for humans.

There was something even more exotic going on in the old verandah bar on the promenade deck. With the dance floor covered over, the bar had been converted into a lab where more of Nathan’s pet scientists were trying to develop a radically new form of solar cell. The panels on the Ark’s sports deck, conventional titanium-coated polymer cells, had an efficiency of ten percent, but photosynthesizing algae could trap up to ninety-seven percent of the incoming solar energy. Nathan’s bioengineers hoped to be able to grow bright green solar panels like leaves, coated with the light-harvesting pigment molecules to be found in the algal cells. Nathan intended that in the long term these new solar arrays, with the support of the OTEC, could make the ship independent of resupply of uranium for its primary power plant. And in a world where sunlight was about the most easily accessible energy source of all, the new technology could be hugely commercially valuable.

But Nathan had deeper purposes in mind than trade. All these projects were facets of his greater vision.

Nobody expected the voyage to last forever; sooner or later this new Ark would come to rest on its own Ararat. But in the meantime Nathan wanted to make his floating city entirely independent of the land. He could feed himself from the sea, and collect fresh water from the rain. With the OTEC and his solar cells he hoped to harvest useful energy from the sea and the sun, and with his sea concrete and magnesium he hoped to be able to maintain the fabric of the ship herself from the resources of the sea, without resupply of any kind from the land. Lily imagined a day off in the future where every bit of the ship had worn out and been replaced by materials extracted from the sea. It would be the ultimate defiance of the flood and the damage it had wrought to human ambitions.

For all his faults, Nathan was a kind of genius of foresight, Lily acknowledged. Maybe the world needed such dreamers, as she remembered Sanjay McDonald once saying to her. She often wondered how long she could have survived without the shelter Nathan had given her since Barcelona.

Of course that wasn’t to say that his dream of his ship-city sailing endlessly on the sea was actually going to come true, any more than his Andean enclave had ultimately survived its greatest challenge.

They completed their usual twenty laps, a distance of around eight kilometers. On the last lap Kristie came out to wait for Lily, leaning on the rail.

Lily pulled up beside her. Kristie let her aunt get her breath. Piers ducked indoors, heading for his cabin and a shower-salt water, that was the only choice now. Kristie didn’t acknowledge him, didn’t even look at him. She had brought a couple of mugs of coffee substitute. Lily drank gratefully, though she would have preferred fresh water, even the vaguely chemical-smelling stuff that came out of the ship’s reverse-osmosis desalination plants.

This morning Kristie was ready for work. Over a regular AxysCorp coverall she wore a light protective suit with a hood and goggles, and had thick gloves tucked in her waistband. She worked in a plant that had been built into the ballroom, where the shells of crab, shrimp and lobster were processed for their chitin, a substance that was used as a cellulose substitute in the manufacture of paper and cardboard. It was one of Nathan’s more ingenious schemes, a product of his endless quest to find ways for the Ark and its passengers to make a living: they could sell crustacean-shell paper to other seaborne societies. Lily thought this wasn’t as good an idea, however, as the little optical workshops Nathan had set up elsewhere aboard the ship, where spectacles lenses were ground; people would need to be able to see long after they had given up writing things down.