“Well,” Art said uneasily. “Well, after all.” But on she raged. She couldn’t stop until she felt less angry. And Art could see that it was getting harder every time.
Flailing a bit himself, he recommended she start another conference, like the one in Sabishii she had missed; and make sure she made this one. Organizing the efforts of different organizations for a single cause; this was not really building, Nadia thought, but it looked like it would have to do.
The fight in Cairo had gotten her thinking about the hy-drological cycle, and what would happen when the ice began to melt. If they could set up some kind of plan for a water cycle, even only an approximation, then it might go far toward reducing conflicts over water. So she decided to see what could be done.
As often happened these days when she thought about global issues, she found herself wanting to talk to Sax about it. The travelers to Earth were almost back now, close enough that transmission delay was insignificant, it was almost like having a normal wrist conversation. So Nadia spent evenings talking with Sax about terraforming. More than once he surprised her utterly; he did not hold the opinions she had imagined he would hold, he seemed always to be changing. “I want to keep things wild,” he said one night.
“What do you mean?” she asked.
His face took on the puzzled expression it wore when he was thinking hard. It was considerably longer than the transmission delay before he replied: “Many things. It’s a complicated word. But — I mean — I want to maintain the primal landscape, as much as possible.”
Nadia could censor out her laughter at this; but still Sax said, “What do you find amusing?”
“Oh nothing. It’s just you sound like, I don’t know, like some of the Reds. Or the people in Christianopolis, they’re not Reds, but they said almost the same thing to me, last week. They want to keep the primal landscape of the far south preserved. I’ve helped them to set up a conference to talk about southern watersheds.”
“I thought you were working on greenhouse gases?”
“They won’t let me work, I have to be president. But I am going to go to this conference.”
“Good idea.”
The Japanese settlers in Messhi Hoko (which meant “self-sacrifice for the sake of the group”) came to the council to demand that more land and water be dedicated to their tent high on south Tharsis. Nadia walked out on them, and flew with Art down to Christianopolis, in the far south.
The little town (and it seemed very little after Sheffield and Cairo) was set in Phillips Rim Crater Four, at latitude sixty-seven degrees south. During the Year Without Summer the far south had experienced many severe storms, dropping about four meters of new snow, an unprecedented amount; the previous record for a year had been less than one. Now it was Ls 281, just after perihelion, and high summer in the south. And the various abatement strategies for avoiding an ice age seemed to be working well; most of the new snow had melted in a hot spring, and now there were round lakes on every crater floor. The pond in the center of Christianopolis was about three meters deep, and three hundred meters across; this was fine with the Christians, as it gave them a nice park pond. But if the same thing happened every winter — and the meteorologists believed that the coming winters would drop even more snow, and the coming summers get ever warmer — then their town would quickly be inundated by snowmelt, and Phillips Rim Crater Four become a lake full to the brim. And this was true for craters all over Mars.
The conference in Christianopolis had been convened to discuss strategies to deal with this situation. Nadia had done what she could to get influential people down to it, including meteorologists, hydrologists, and engineers, and the possibility of Sax, whose return was imminent. The problem of crater flooding was to be only the initial point of discussion for the whole question of watersheds, and the planetary hydrological cycle itself.
The crater problem specifically was to be solved as Nadia had predicted: plumbing. They would treat the craters like bathtubs, and drill drains to empty them. The brecciated pans under the dusty crater floors were extremely hard, but they could be tunneled through robotically; then install pumps and filters and pump the water out, keeping a central pond or lake if one wanted, or draining it dry.
But what were they going to do with the water they pumped out? The southern highlands were everywhere lumpy, shattered, pocked, cracked, hillocky, scarped, slumped, fissured, and fractured; when analyzed as potential watersheds, they were hopeless. Nothing led anywhere; there was no downhill for long. The entire south was a plateau three to four kilometers above the old datum, with only local bumps and dips. Never had Nadia seen more clearly the difference between this highland and any continent on Earth. On Earth, tectonic movement had pushed up mountains every few-score million years, and then water had run down these fresh slopes, following the paths of least resistance back to the sea, carving the fractal vein patterns of watersheds everywhere. Even the dry basin regions on Earth were seamed with arroyos and dotted with playas. In the Martian south, however, the meteoric bombardment of the Noachian had hammered the land ferociously, leaving craters and ejecta everywhere; and then the battered irregular wasteland had lain there for two billion years under the ceaseless scouring of the dusty winds, tearing at every flaw. If they poured water onto this pummeled land they would end up with a crazy quilt of short streams, running down local inclines to the nearest rimless crater. Hardly any streams would make it to the sea in the north, or even into the Hellas or Argyre basins, both of which were ringed by mountain ranges of their own ejecta.
There were, however, a few exceptions to this situation. The Noachian Age had been followed by a brief “warm wet period” in the late Hesperian, a period perhaps as short as a hundred million years, when a thick warm CO2 atmosphere had allowed liquid water to run on the surface, carving some river channels down the gentle tilts of the plateau, between crater aprons diverting them this way and that. And these watercourses had of course remained after the atmosphere had frozen out, empty arroyos gradually widened by the wind. These fossil riverbeds, like Nirgal Vallis, Warrego Valles, Protva Valles, Patana Valles, or Oltis Vallis, were narrow sinuous canyons, true riverine canyons rather than grabens or fossae. Some of them even had immature tributary systems. So efforts to design a macro-watershed system for the south naturally used these canyons as primary watercourses, with water pumped to the head of every tributary. Then there were also a number of old lava channels that could easily become rivers, as the lava, like the water, had tended to follow the path of least resistance downhill. And there were a number of tilted graben fractures and fissures, as at the foot of the Eridania Scopulus, that could likewise be turned to use.
In the conference, big globes of Mars were marked up daily to display different water regimes. There were also rooms full of 3-D topo maps, with groups standing around different watershed systems, arguing their advantages and disadvantages, or simply contemplating them, or fiddling with the controls to change them, restlessly, from one pattern to another. Nadia wandered the rooms looking at these hydrographies, learning much about the southern hemisphere that she had never known. There was a six-kilometer-high mountain near Richardson Crater, in the far south. The south polar cap itself was quite high. Dorsa Brevia, on the other hand, crossed a depression that looked like a ray cut out from the Hellas impact, a valley so deep that it ought to become a lake, an idea that the Dorsa Brevians naturally did not like. And certainly the area could be drained if they cared to do it. There were scores of variant plans, and every single system was strange looking to Nadia. Never had she seen so clearly how different a gravity-driven fractal was from impact randomness. In the inchoate meteoric landscape, almost anything was possible, because nothing was obvious — nothing except for the fact that in any possible system, some canals and tunnels would have to be built. Her new finger itched with the desire to get out there and run a bulldozer or a tunnel borer.