Authors: Kim Stanley Robinson
He woke and it was still light. He had no idea what time it was. He checked his watch: 7:04
A.M
. Val was not in her bag; it lay pulled down toward the door, a suggestively Val-shaped hole still in it.
He took his boots from under his head and put them on; then, as he was quickly chilling, his parka. He rolled forward with a stiff groan, and crawled out into the brilliant frigid morning. The sun was standing over a different ridge, no doubt the east ridge; he had given up trying to orient himself in McMurdo, but out here it might be possible, if you stayed put long enough. He needed to use his pee bottle again, and there was a rock outhouse up the hill, away from the white surface of the lake. Yellow hair shone over its top rocks. He looked away, down at the lake. It was cold, but in his parka he felt comfortable. Hungry, however. Very hungry.
He joined the group, which had already reconvened in the Scott tent, and they ate oatmeal and crackers and chocolate bars hastily, as if oppressed by the very same crowded tent that twelve hours earlier had been such a comfy refuge. Then it was outside again, where they occupied themselves filling backpacks, and taking turns up at the rock outhouse.
“Can I carry anything?” Wade asked Professor Michelson.
“No, thank you. But bring your pack, and you can help carry samples on the way back.”
Val and Misha took off ahead of the scientists, who followed them up the valley. Distant red dots, bobbing in the rock rubble under the white mass of the glacier.
“Why are the Dry Valleys dry?” Wade asked Michelson as they hiked along.
“It’s not entirely understood. But people usually agree that the mountains at the heads of these valleys are so high that they choke off the ice sliding down
from the polar cap. In places some ice spills over, but the winds ablate the ice faster than it pours through the passes, and so you have the hanging glaciers you see—” gesturing ahead “—steep-sided because of the ablation, and fairly static in position. At least they have been since their discovery. Now, however …”
“The global warming?”
“Well, yes. There’s no doubt the climate has warmed in the last century, because of carbon dioxide that we’ve put in the atmosphere.”
Wade nodded sharply, intending to say that this was a fact known even to Washington bureaucrats.
“Yes yes,” Michelson acknowledged, “you know about that. But the effects of this warming on Antarctica aren’t entirely clear. At first, you see, the warming increases precipitation down here, in the form of more snow, it not being so warm as to rain. And so the ice caps and the glaciers and the sea ice actually tend to grow. At least that is one force involved. So the Dry Valleys could be iced over again, as they have been before, if that were the only thing going on. In fact this snow you see on the ground here—this would have been very unusual at this time of year, thirty years ago. Now the valleys are snowy more often than they’re bare, and they’re never less than piebald, if you see what I mean. Which is no help at all to people trying to study them.”
“What about the big ice shelves breaking off?”
“Well, those turned out to be very sensitive to slight temperature increases. They’ve broken off because of their own dynamic with the ocean temperatures and currents, or so we think. Then as they detach and float off north, the ice coming down from the polar cap has nothing to slow it down, and so there are the immense ice tongues that we’re seeing, and very fast ice streams
and glaciers, and even a slight sinking of the polar cap itself, if the Ohio State people’s results are correct. But with more snow up there as well, it’s hard to know what the upshot will be.”
Wade nodded again, more agreeably. Establishing the ground of understanding with experts who were explaining things to him was his responsibility; nod too often, and the expert was likely to give up entirely; but in the absence of any sign of response, some of them would begin to explain everything. Michelson appeared to have a tendency in the latter direction, so Wade said, “But if global warming takes things up to the point where it’s above freezing down here for periods every summer?”
“Well, then things start melting.”
“Uh huh …”
“And with the ice shelves already substantially gone, and the ice streams, which are like ice rivers within the West Antarctic ice sheet, speeding up—then the ice sheets themselves will begin to detach. The western Antarctic ice sheet is grounded on land that is well below sea level, so it comes off very quickly. The eastern sheet is much larger, and more of it is grounded above sea level, so it will hold longer, but still, the warmer it gets the faster it will go, more precipitation or not. And if the eastern sheet goes, then sea level will be some sixty to seventy meters higher than it is now.”
“You’d think that would be enough of a threat to get everyone’s attention.”
“Yes, but it’s so inconvenient. If we have to take global warming seriously, then everything changes. CO
2
levels have to drop, industrial society can’t keep burning fossil fuels—we would have to live differently. It’s so much easier to find some scientist somewhere who would be ever so happy to appear before a Congressional
committee and declare that there is no such thing as global warming, or if there is that it isn’t really a problem, or that burning fossil fuels has nothing to do with it. Then the problem can be declared nonexistent by law and everyone can go back to business as usual.”
“You mean Professor Warren?”
“Yes,” Michelson said, nodding in approval at Wade’s recognition.
In fact Professor Warren’s appearance before the Senate Foreign Relations Committee had caused quite a stir, as Wade well knew, having been put in charge of substantiating Phil Chase’s rebuttal to the professor. It was slightly possible Michelson was aware of Chase’s opposition to the renegade professor, rather than knowing only that the committee as a whole had endorsed Warren’s views enthusiastically, and used them to justify the blockage of the CO
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joint implementation treaty with China. But it was hard to tell; between beard, sunglasses, and black leather nose protector attached to the sunglasses, Michelson’s was a hard face to read. A face from a Breughel painting, really. Best to make no assumptions.
“Is this where we’re going?” Wade asked, pointing up a side valley where Graham Forbes was just in view.
“Yes. Follow Graham. Up into the Apocalypse Peaks,” he announced with some satisfaction.
Hiking uphill on the brown pebbly snow-crusted rubble was hard work, and Wade started to heat up. He unzipped his parka and let the cold air cool him a bit. Unfortunately no matter how hot his torso became, his ears and nose continued to freeze.
As they climbed higher they could see farther up the hanging valley. A glacier ran down its middle, reaching almost to the frozen lakes on the floor of Barwick Valley. Higher still and they could see the source of the
glacier, a big tongue of ice pouring through the gap between two black rock ridges. Above and beyond that tongue the whole world was white. The edge of the polar cap, as Michelson confirmed; enough ice to cover the United States and Mexico. “These Dry Valleys are very unusual, you must remember that. It will be a shame if they get overrun by the ice.” Michelson ascended at a steady relaxed pace, and appeared neither too hot nor too cold. “That’s Shapeless Mountain. Beyond it is Mistake Peak. Over there, Mount Bastion and the Gibson Spur. These are all peaks of the Willett Range, and the ice cap is running up against their southern flanks, and through the passes between them, as here.”
“You like the names.”
“Yes,” surprised, “I do.”
He led Wade under the side of the glacier, right up to its faceted cliff of a sidewall, which gleamed pale blue in the bright sun. Spills of broken ice splayed out from the wall here and there, as if ice machines had churned out a vast oversupply of ice cubes. “See how rounded all the chunks are,” Michelson pointed out. “They’re subliming away in the arid winds, and they’ll be gone before there’s another calving in the same spot. That’s why there’s no build-up of ice, and the glacier’s sides are sheer like this. They break off as a result of slow pressure from behind, and then the wind cleans up the mess at the bottom.”
Eventually they climbed onto a section of rubble bordering the glacier that ramped up until it was level with the broad surface of the glacier, then just above it, so that they could see beyond the glacier, and a long way up the ice plain of the polar cap, rising gently to the south. It was not perfectly smooth, but had broad undulations that formed very low hills and valleys, Wade
saw; subtle contours of up and down, all very smooth except in certain zones, where it was completely shattered. A kind of white frozen ocean, pouring through a break in the shore and down to a lower world. Also curving down in places to stand right over the shore, like waves that would never break. Puffing, sweat stinging one eye, Wade was nevertheless fascinated by the sight, glaring even through his polarized sunglasses; it was surreal, a kind of Dalí landscape, with all its features made impossible and subtly ominous, as the ocean bulked higher than the land, and one surge of the immense white wave would sweep them all away.
But of course it stayed put. Michelson had hiked ahead, and joined Graham Forbes between the glacier and a broken cliff of reddish stone facing it. There at the foot of the red stone was a band of lighter sandstone, freckled with pebbles embedded in it. Graham Forbes was already kneeling before this sandstone, tapping away with a geologist’s hammer.
“Now this is a very nice example of the Sirius group,” Michelson said as Wade approached them. “Almost a textbook example of it, in that it would make a good photo in a textbook. See how it’s laminated against the dolerite? Like the dirty ring of a bathtub. It’s a sedimentary rock, called tillite or diamictite, depending. Glacial till, from an ancient glacier.”
“Not from this one?” Wade said, gesturing at the ice mass looming behind them.
“No, from a predecessor. It’s been here a while.”
“How long?”
A snort from Forbes.
Michelson’s moustache lifted at the corners. “That’s the question, isn’t it. We maintain that some Sirius group sandstones date from around three million years ago.”
“Other people don’t agree?”
“That’s right. There are those who say that the eastern ice cap has been very stable, and has been here for fourteen million years at least. So—” He shrugged. “We look at Sirius sandstone wherever we can find it, and see what we can see.”
“How have you established the three-million-year date?”
“There are microfossils buried in the rock, the fossil remnants of marine diatoms and foraminifera. These creatures have evolved over time, so that different kinds have lived in different eras, and the diatom record on the ocean floor is very well stratified and preserved. So when you find certain kinds of diatom fossils, you can match them with the record and say with fair confidence that the rock they are in is of a certain age.”
“And this is a real method—I mean, an accepted method?”
The little smile. “Oh yes, very real. It’s called biostratification, and it’s very well established.”
“I see.”
“We’ve also found evidence of a fuller biological community than just marine diatoms—members of a beech tree forest biome. Which suggests it was so warm that the ice cap would have been substantially gone, with western Antarctica an archipelago, and even eastern Antarctica covered in parts by shallow seas.”
“You carbon-14 dated the beech trees?”
“No no, carbon-14 dating only works for a short distance back in time. These are much older. And beech trees have remained stable evolutionarily for many millions of years, so we can’t date them by their type. There are some beetle fragments among the beech remains, however, and some other plants, lichens and mosses, and some of these can be dated using various
methods, uranium-lead, argon-argon, amino acid … every little bit of biological material in Sirius tends to add its part to the puzzle.”
“Look,” Forbes said to Michelson, pointing with the geologist’s hammer to the rock of the slope at about his knee level. “A dropstone of diamictite, within the massive diamicton here.”
Wade saw that a round boulder of sandstone, the same color as the rest but with more pebbles in it, was embedded in the rest of the sandstone.
“Interesting!” Michelson said, going to one knee to have a closer look. “So this boulder must be very much older than the matrix.”
“Older, anyway,” Forbes allowed.
They continued to discuss the band of sandstone, pointing out features invisible to Wade. “Do you think this could be our D-7 disconformity again, cropping up here?”
“It looks like that could be some crude stratification below it, see that.”
“And above, massive clast-rich diamictite, with dolerite boulders, and more water-lain gravels.”
Back and forth they went, in a flurry of terms, as they wandered up and down the slope: deformed laminites, clast-poor muddy diamictite, rudimentary paleosols, lonestones, metasediments; “And then at the bottom the Dominion erosion surface again, perhaps. See how scoured this dolerite is, with north-south striations.”
“Very nice,” Michelson said.
They were seeing much more in this rock than Wade had ever realized could be there, much as he might hear more than them if confronted with an unfamiliar piece by Poulenc. They were reading the landscape like a text, even like a work of art in some senses.
“See here!” Michelson exclaimed to Forbes, pointing at a patch of whitish rock at one end of the sandstone band, laminated very finely. “Silt layers, calcite crystals perhaps, and deposited here certainly—these couldn’t have been moved here, they’re much too delicate, see? You can break the layers with a finger.” He demonstrated. “Beautiful.”
“I’ll take some samples,” Forbes said, getting a flat rectangular white canvas bag out of his daypack.
“Is this the first time you’ve found this kind of thing?” Wade asked, feeling pleased: a scientific discovery!
“The first time here, anyway.”
“And what does this indicate?”