"The weather's too dicey for helicopters, so we have to take snow-tracks. It's seventeen miles to the camp. The snowtracks should get us there in two hours. The outside temperature's perfect for springtime in Antarcticaminus twenty-five degrees Fahrenheit. So, bundle up. Any questions?"

Evans glanced at his watch. "Won't it get dark soon?"

"We have much less nighttime now that spring is here. We'll have daylight all the time we're out there. The only problem we face is right here," Kenner said, pointing to the map. "We have to cross the shear zone."

Chapter 33

THE SHEAR ZONE

WEDNESDAY, OCTOBER 6

12:09 P.M.

"The shear zone?" Jimmy Bolden said, as they trudged toward the vehicle shed. "There's nothing to it. You just have to be careful, that's all."

"But what is it?" Sarah said.

"It's a zone where the ice is subjected to lateral forces, shear forces, a bit like the land in California. But instead of having earthquakes, you get crevasses. Lots of 'em. Deep ones."

"We have to cross that?"

"It's not a problem," Bolden said. "Two years ago they built a road that crosses the zone safely. They filled in all the crevasses along the road."

They went into the corrugated steel shed. Evans saw a row of boxy vehicles with red cabs and tractor treads. "These are the snowtracks," Bolden said. "You and Sarah'll go in one, Dr. Kenner in one, and I'll be in the third, leading you."

"Why can't we all go in one?"

"Standard precaution. Keep the weight down. You don't want your vehicle to fall through into a crevasse."

"I thought you said there was a road where the crevasses were filled in?"

"There is. But the road is on an ice field, and the ice moves a couple of inches a day. Which means the road moves. Don't worry, it's clearly marked with flags." Bolden climbed up onto the tread. "Here, let me show you the features of the snowtrack. You drive it like a regular car: clutch there, handbrake, accelerator, steering wheel. You run your heater on this switch here" he pointed to a switch "and keep it on at all times. It will maintain the cab at around ten above zero. This bulgey orange beacon on the dashboard is your transponder. It turns on when you push this button here. It also turns on automatically if the vehicle shifts more than thirty degrees from horizontal."

"You mean if we fall into a crevasse," Sarah said.

"Trust me; that isn't going to happen," Bolden said. "I'm just showing you the features. Transponder broadcasts a unique vehicle code, so we can come and find you. If for any reason you need to be rescued, you should know the average time to rescue is two hours. Your food is here; water here; you have enough for ten days. Medical kit here, including morphine and antibiotics. Fire extinguisher here. Expedition equipment in this boxcrampons, ropes, carabiners, all that. Space blankets here, equipped with mini heaters; they'll keep you above freezing for a week, if you crawl inside 'em. That's about it. We communicate by radio. Speaker in the cab. Microphone above the windshield. Voice-activatedjust talk. Got it?"

"Got it," Sarah said, climbing up.

"Then let's get started. Professor, you clear on everything?"

"I am," Kenner said, climbing up into the adjacent cab.

"Okay," Bolden said. "Just remember that whenever you are outside your vehicle, it is going to be thirty below zero. Keep your hands and face covered. Any exposed skin will get frostbite in less than a minute. Five minutes, and you're in danger of losing anatomy. We don't want you folks going home without all your fingers and toes. Or noses."

Bolden went to the third cab. "We proceed single file," he said. "Three cab-lengths apart. No closer under any circumstances, and no farther. If a storm comes up and visibility drops, we maintain the same distance but reduce our speed. Got it?"

They all nodded.

"Then let's go."

At the far end of the shed, a corrugated door rolled up, the icy metal screeching. Bright sunlight outside.

"Looks like a beautiful day in the neighborhood," Bolden said. And with a sputter of diesel exhaust, he drove the first snowtrack out through the door.

It was a bouncing, bone-jolting ride. The ice field that had looked so flat and featureless from a distance was surprisingly rugged when experienced up close, with long troughs and steep hillocks. Evans felt like he was in a boat, crashing through choppy seas, except of course this sea was frozen, and they were moving slowly through it.

Sarah drove, her hands confident on the wheel. Evans sat in the passenger seat beside her, clutching the dashboard to keep his balance.

"How fast are we going?"

"Looks like fourteen miles an hour."

Evans grunted as they nosed down a short trench, then up again. "We've got two hours of this?"

"That's what he said. By the way, did you check Kenner's references?"

"Yes," Evans said, in a sulky voice.

"Were they made up?"

"No."

Their vehicle was third in the row. Ahead was Kenner's snowtrack, following behind Bolden's in the lead.

The radio hissed. "Okay," they heard Bolden say, over the speaker. "Now we're coming into the shear zone. Maintain your distance and stay within the flags."

Evans could see nothing differentit just looked like more ice field, glistening in the sunbut here there were red flags on both sides of the route. The flags were mounted on six-foot-high posts.

As they moved deeper into the field, he looked beyond the road to the openings of crevasses in the ice. They had a deep blue color, and seemed to glow.

"How deep are they?" Evans said.

"The deepest we've found is a kilometer," Bolden said, over the radio. "Some of them are a thousand feet. Most are a few hundred feet or less."

"They all have that color?"

"They do, yes. But you don't want a closer look."

Despite the dire warnings, they crossed the field in safety, leaving the flags behind. Now they saw to the left a sloping mountain, with white clouds.

"That's Erebus," Bolden said. "It's an active volcano. That's steam coming from the summit. Sometimes it lobs chunks of lava, but never this far out. Mount Terror is inactive. You see it ahead. That little slope."

Evans was disappointed. The name, Mount Terror, had suggested something fearsome to himnot this gentle hill with a rocky outcrop at the top. If the mountain hadn't been pointed out to him, he might not have noticed it at all.

"Why is it called Mount Terror?" he said. "It's not terrifying."

"Has nothing to do with that. The first Antarctic landmarks were named after the ships that discovered them," Bolden said. "Terror was apparently the name of a ship in the nineteenth century."

"Where's the Brewster camp?" Sarah said.

"Should be visible any minute now," Bolden said. "So, you people are some kind of inspectors?"

"We're from the IADG," Kenner said. "The international inspection agency. We're required to make sure that no US research project violates the international agreements on Antarctica."

"Uh-huh amp;"

"Dr. Brewster showed up so quickly," Kenner went on, "he never submitted his research grant proposal for IADG approval. So we'll check in the field. It's just routine."

They bounced and crunched onward for several minutes in silence. They still did not see a camp.

"Huh," Bolden said. "Maybe he moved it."

"What type of research is he doing?" Kenner said.

"I'm not sure," Bolden said, "but I heard he's studying the mechanics of ice calving. You know, how the ice flows to the edge, and then breaks off the shelf. Brewster's been planting GPS units in the ice to record how it moves toward the sea."

"Are we close to the sea?" Evans said.

"About ten or eleven miles away," Bolden said. "To the north."

Sarah said, "If he's studying iceberg formation, why is he working so far from the coast?"

"Actually, this isn't so far," Kenner said. "Two years ago an iceberg broke off the Ross Shelf that was four miles wide and forty miles long. It was as big as Rhode Island. One of the biggest ever seen."

"Not because of global warming, though," Evans said to Sarah, with a disgusted snort. "Global warming couldn't be responsible for that. Oh no."

"Actually, it wasn't responsible," Kenner said. "It was caused by local conditions."

Evans sighed. "Why am I not surprised?"

Kenner said, "There's nothing wrong with the idea of local conditions, Peter. This is a continent. It would be surprising if it didn't have its own distinctive weather patterns, irrespective of global trends that may or may not exist."

"And that's very true," Bolden said. "There are definitely local patterns here. Like the katabatic winds."

"The what?"

"Katabatic winds. They're gravitational winds. You've probably noticed that it's a lot windier here than in the interior. The interior of the continent is relatively calm."

"What's a gravitational wind?" Evans said.

"Antarctica's basically one big ice dome," Bolden said. "The interior is higher than the coast. And colder. Cold air flows downhill, and gathers speed as it goes. It can be blowing fifty, eighty miles an hour when it reaches the coast. Today is not a bad day, though."

"That's a relief," Evans said.

And then Bolden said, "See there, dead ahead. That's Professor Brewster's research camp."

Chapter 34

BREWSTER CAMP

WEDNESDAY, OCTOBER 6

2:04 P.M.

It wasn't much to look at: a pair of orange domed tents, one small, one large, flapping in the wind. It looked like the large one was for equipment; they could see the edges of boxes pressing against the tent fabric. From the camp, Evans could see orange-flagged units stuck into the ice every few hundred yards, in a line stretching away into the distance.

"We'll stop now," Bolden said. "I'm afraid Dr. Brewster's not here at the moment; his snowtrack is gone."

"I'll just have a look," Kenner said.

They shut the engines and climbed out. Evans had thought it was chilly in the cab, but it was a shock to feel the cold air hit him as he stepped out onto the ice. He gasped and coughed. Kenner appeared to have no reaction; he went straight for the supply tent and disappeared inside.

Bolden pointed down the line of flags. "You see his vehicle tracks there, parallel to the sensor units? Dr. Brewster must have gone out to check his line. It runs almost a hundred miles to the west."

Sarah said, "A hundred miles?"

"That's right. He has installed GPS radio units all along that distance. They transmit back to him, and he records how they move with the ice."

"But there wouldn't be much movement amp;"

"Not in the course of a few days, no. But these sensors will remain in place for a year or more. Sending back the data by radio to Weddell."

"Dr. Brewster is staying that long?"

"Oh no, he'll go back, I'm sure. It's too expensive to keep him here. His grant allows an initial twenty-one-day stay only, and then monitoring visits of a week every few months. But we'll be forwarding his data to him. Actually, we just put it up on the Internet; he takes it wherever he happens to be."

"So you assign him a secure web page?"

"Exactly."

Evans stamped his feet in the cold. "So, is Brewster coming back, or what?"

"Should be coming back. But I couldn't tell you when."

From within the tent, Kenner shouted, "Evans!"

"I guess he wants me."

Evans went to the tent. Bolden said to Sarah, "Go ahead with him, if you want to." He pointed off to the south, where clouds were darkening. "We don't want to be staying here too long. Looks like weather coming up. We have two hours ahead of us, and it won't be any fun if it socks in. Visibility drops to ten feet or less. We'd have to stay put until it cleared. And that might be two or three days."

"I'll tell them," she said.

Evans pushed the tent flap aside. The interior glowed orange from the fabric. There were the remains of wooden crates, broken down and stacked on the ground. On top of them were dozens of cardboard boxes, all stenciled identically. They each had the University of Michigan logo, and then green lettering:

University of Michigan

Dept. of Environmental Science

Contents: Research Materials

Extremely Sensitive

HANDLE WITH CARE

This Side Up "Looks official," Evans was saying. "You sure this guy isn't an actual research scientist?"

"See for yourself," Kenner said, opening one cardboard carton. Within it, Evans saw a stack of plastic cones, roughly the size of highway cones. Except they were black, not orange. "You know what these are?"

"No." Evans shook his head.

Sarah came into the tent. "Bolden says bad weather coming, and we shouldn't stay here."

"Don't worry, we won't," Kenner said. "Sarah, I need you to go into the other tent. See if you can find a computer there. Any kind of computerlaptop, lab controller, PDAanything with a microprocessor in it. And see if you can find any radio equipment."

"You mean transmitters, or radios for listening?"

"Anything with an antenna."

"Okay." She turned and went outside again.

Evans was still going through the cartons. He opened three, then a fourth. They all contained the same black cones. "I don't get it."

Kenner took one cone, turned it to the light. In raised lettering it said: "Unit PTBC-XX-904/8776-AW203 US DOD."

Evans said, "These are military?"

"Correct," Kenner said.

"But what are they?"

"They're the protective containers for coned PTBs."

"PTBs?"

"Precision-timed blasts. They're explosives detonated with millisecond timing by computer in order to induce resonant effects. The individual blasts are not particularly destructive, but the timing sets up standing waves in the surrounding material. That's where the destructive power comes fromthe standing wave."