Nirgal looked back and forth between the two silent men. “I’ve looked for her too,” he said. And then, seeing the blasted look on Sax’s face: “Anything’spossible.”

Coyote shook his head. He went back into the kitchen, muttering to himself. Sax looked at Nirgal, stared right through him.

“Maybe I’ll try looking for her again,” Nirgal told him.

Sax nodded.

“Beats farming,” Coyote said from the kitchen.

Recently Harry Whitebook had found a methodfor increasing animal tolerance to CO₂, by introducing into mammals a gene which coded for certain characteristics of crocodile hemoglobin. Crocodiles could hold their breath for a very long time underwater, and the CO₂ that should have built up in their blood actually dissolved there into bicarbonate ions, bound to amino acids in the hemoglobin, in a complex that caused the hemoglobin to release oxygen molecules. High CO₂ tolerance was thus combined with increased oxygen-ation efficiency, a very elegant adaptation, and as it turned out fairly easy (once Whitebook showed the way) to introduce into mammals by utilizing the latest trait transcription technology: designed strands of the DNA repair enzyme photolyase were assembled, and these would patch the descriptions for the trait into the genome during the geron-tological treatments, changing slightly the hemoglobin properties of the subject.

Sax was one of the first people to have this trait administered to him. He liked the idea because it would obviate the need for a face mask in the outdoors, and he was spending a lot of his time outdoors. Carbon-dioxide levels in the atmosphere were still at about 40 millibars of the 500 total at sea level, the rest consisting of 260 millibars nitrogen, 170 millibars oxygen, and 30 of miscellaneous noble gases.

So there was still too much CO₂ for humans to tolerate without filter masks. But after trait transcription he could walk free in the air, observing the wide array of animals with similar trait transcriptions already out there. All of them monsters together, settling into their ecological niches, in a very confusing flux of surges, die-offs, invasions and retreats — everything vainly seeking a balance that could not, given the changing climate, exist. No different than life on Earth had ever been, in other words; but here all happening at a much faster rate, pushed by the human-driven changes, modifications, introductions, transcriptions, translations — the interventions that worked, the interventions that backfired — the effects unintended, unforeseen, unnoticed — to the point where many thoughtful scientists were giving up any pretense of control. “Let happen what may,” as Spencer would say when he was in his cups. This offended Michel’s sense of meaning, but there was nothing to be done about that, except to alter Michel’s sense of what was meaningful. Contingency, the flux of life: in a word, evolution. From the Latin, meaning the unrolling of a book. And not directed evolution either, not by a long shot. Influenced evolution perhaps, accelerated evolution certainly (in some aspects, anyway), But not managed, nor directed. They didn’t know what they were doing. It took some getting used to.

So Sax wandered around on Da Vinci Peninsula, a rectangular chunk of land surrounding the round rim hill of Da Vinci Crater, and bounded by the Simud, Shalbatana, and Ravi fjords, all of which debouched onto the southern end of Chryse Gulf. Two islands, Copernicus and Galileo, lay to the west, in the mouths of the Ares and Tiu fjords. A very rich braiding of sea and land, perfect for the burgeoning of life — the Da Vinci lab techs could not have chosen a better site, although Sax was quite sure they had had no sense at all of their surroundings when they chose the crater for the underground’s hidden aerospace labs. The crater had had a thick rim and was located a good distance from Burroughs and Sabishii, and that had been that. Stumbled into paradise. More than a lifetime’s observations to be made, without ever leaving home.

Hydrology, invasion biology, areology, ecology, materials science, particle physics, cosmology: all these fields interested Sax extremely, but most of his daily work in these years concerned the weather. Da Vinci Peninsula got a lot of dramatic weather; wet storms swept south down the gulf, dry katabatic winds dropped off the southern highland and out the fjord canyons, initiating big northward waves at sea. Because they were so close to the equator, the perihelion-aphelion cycle affected them much more than the ordinary inclination seasons. Aphelion brought cold weather twenty degrees north of the equator at least, while perihelion cooked the equator as much as the south. In the Januaries and Februaries, sun-warmed southern air lofted into the stratosphere, turned east at the tropopause and joined the jet streams in their circumnavigations. The jet streams were difluent around the Tharsis Bulge; the southern stream carried moisture from Amazonis Bay, and dumped it on Daedalia and Icaria, sometimes even on the western wall of the Argyre Basin mountains, where glaciers were forming. The northern jet stream ran over the Tempe-Mareotis highlands, then blew over the North Sea, picking up the moisture for storm after storm. North of that, over the polar cap, air cooled and fell on the rotating planet, causing surface winds from the northeast. These cold dry winds sometimes shot underneath the warmer wetter air of the temperate westerlies, causing fronts of huge thunderheads to rise over the North Sea, thunderheads twenty kilometers high.

The southern hemisphere, being more uniform than the north, had winds that followed even more clearly the physics of air over a rotating sphere: southeast trades from the equator to latitude thirty; prevailing westerlies from latitude thirty down to latitude sixty; polar easterlies from there to the pole. There were vast deserts in the south, especially between latitudes fifteen and thirty, where the air that rose at the equator sank again, causing high air pressure and hot air that held a lot of water vapor without condensing; it hardly ever rained in this band, which included the hyperarid provinces of Solis, Noachis, and Hesperia. In these regions the winds picked up dust off the dry land, and the dust storms, while more localized than before, were also thicker, as Sax had witnessed himself, unfortunately, while up on Tyrrhena with Nirgal.

Those were the major patterns in Martian weather: violent around aphelion, gentle during the helionequinoxes; the south the hemisphere of extremes, the north of moderation. Or so some models suggested. Sax liked generating the simulations that created such models, but he was aware that their match with reality was approximate at best; every year on record was an exception of some kind, with conditions changing at each stage of the terraforming. And the future of their climate was impossible to predict, even if one froze the variables and pretended terraformation had stabilized, which it certainly had not. Over and over Sax watched a thousand years of weather, altering variables in the models, and every time a completely different millennium flitted past. Fascinating. The light gravity and the resulting scale height of the atmosphere, the vast vertical relief of the surface, the presence of the North Sea that might or might not ice over, the thickening air, the perihelion-aphelion cycle, which was an eccentricity that was slowly precessing through the inclination seasons; these had predictable effects, perhaps, but in combination they made Martian weather a very hard thing to understand, and the more he watched, the less Sax felt they knew. But it was fascinating, and he could watch the iterations play out all day long.

Or else just sit out on Simshal Point, watching clouds flow across hyacinth skies. Kasei Fjord, off to the northwest, was a wind tunnel for the strongest katabatic blows on the planet, winds pouring out of it onto Chryse Gulf at speeds that occasionally reached five hundred kilometers an hour. When these howlers struck Sax could see the cinnamon clouds marking them, over the horizon to the north. Ten or twelve hours later big swells would roll in from the north, and rise up and hammer the sea cliffs, fifty-meter-high wedges of water blasting to spray against the rock, until the air all over the peninsula was a thick white mist. It was dangerous to be at sea during a howler, as he had found out once while sailing the coastal waters of the southern gulf, in a little catamaran he had learned to operate.