Antarctica

by Gabrielle Walker

  The fluid wasn’t there as a lubricant—it was to keep the hole open. The ice was so plastic, so strong and so determined to revert to its original form that beyond a kilometre or so of depth the mere time it took to bring the drill up after one run and send it down for the next would be enough for the hole to start closing. This heady fluid was the perfect density to resist the shoving and squeezing of the ice sheet.

  The floor of the tent was wooden, and the scene was dominated by a vertical steel drill tower that reached almost to the ceiling. A hefty cable fed by a winch was threaded through the tower and disappeared into the ground. On the far wall, three posters decorated with hand-drawn penguins marked the dates in past years when the drillers reached 1,000 m, 2,000 m and 3,000 m below the surface. This season they had only a few hundred metres left to drill and they were very close to the end.

  One person—an Italian, judging by his outfit—was standing by the tower watching the disappearing cable. Several other people were inside a small hut with glass walls, crowded round a bank of computers. I recognised one of them, the chief driller, Laurent Augustin. I’d met Laurent before, when I went to interview him in Grenoble. He was compact of build, friendly but introspective, and I knew that some found him aloof. He wrote poetic descriptions of the landscape; he went for long solitary walks and he meditated; he was vegetarian, didn’t drink alcohol and had banned smoking from any of his workplaces, to the great chagrin of many of the French workers; he was also one of the world’s most experienced ice drillers, had spent decades both here and in Greenland, and understood better than most the strange, temporary intensity of life on the ice.

  When I entered the hut Laurent greeted me with a smile and made room for me around the computer. But the atmosphere was tense and he told me that the drilling was getting steadily harder. Close to the surface the ice was at -65°F but, surprisingly, the deeper you went the warmer it got until, near the bedrock, the gentle heat emanating upwards from the Earth’s interior was enough to warm the ice almost to its melting point. That was a double problem for the drillers. Soft ice was harder to cut, so barrel after barrel had returned to the surface empty. And worse, as the cutter’s teeth bit, the ice around it could melt then refreeze, potentially jamming the drill down the hole for ever.

  To try to get around this, Laurent was borrowing an idea from his Greenland days. For these last few runs, he was now attaching a long transparent sausage-like length of plastic to the barrel, filled with a mixture of alcohol and water. There was a spare one on the shelf beside me. It looked bizarrely low-tech, like the sort of party balloons that you twist into doggy shapes to amuse children. When the drill started rotating, a tiny screw would rip into the plastic, allowing alcohol to flood the hole right next to the drill head. This should keep any melted ice from refreezing long enough for the drill to get in and out without sticking. Or at least that was the idea. The team called this contraption a ‘cognac bomb’.

  The drill head had just reached the ice and Saverio, who was at the controls, was about to start cutting. Coloured lines on the computer screen reared up as the various activities went into distant action. The drill was now rotating, the cognac bomb must have burst and spilled its contents around the cutting head. But something seemed to be wrong. The current was soaring in the cutting motor. Saverio hastily switched off the blades and instructed the winch to pull on the cable. Now everyone’s eyes turned to a small white box, whose red LEDs showed a number that was steadily rising. It said 5,000, then 10,000, then 15,000. Heeeaaave.

  As the tension on the cable rose, so did the tension in our small hut until, at 17,463, the cable suddenly rattled into upward action and there was a collective sigh of relief. There might be no core, but at least the drill was free. Everyone stood down from the computer and Laurent told me that we now had nearly an hour to wait until the drill—moving at a human walking pace—would reach the surface. I was astonished by this statistic. It was easy to believe that the ice extended more than two miles below my feet, but the idea that it would take me nearly an hour of walking vertically downwards to reach the bedrock made it seem both farther away and more real.

  This run was likely to be a bust, but the team wanted to bring up the drill to see if there were any clues about why it nearly stuck. This was more important than it sounded, because six years ago, when the drill really did jam, the game was almost lost.

  Dôme C, 20/12/1998.

  Diary of Laurent Augustin

  It’s Sunday, 13k. I take the controls after the Saturday evening break and send the drill down for the first pass of the week. 700m, 780m, 784m. I stop the descent 2 metres above the bottom of the hole and start to approach slowly. Everything is normal: motor current, suspension, temperature, inclination, the values are all normal. The knife slowly starts cutting the ice. The motor current rises.

  It is rising far too much.

  ‘What’s happening? The current is more than 3 Amps.’ I’m forced to stop the progress of the drill—if not it’s going to jam in the bottom. Immediately the motor current returns to normal.

  ‘Ouf.’

  I wait a few minutes for the whole thing to stabilise. All is perfect again.

  ‘But what happened? Perhaps an accumulation of chippings at the bottom of the hole during the Saturday evening break?’

  I start the drilling again, even more carefully. The teeth have barely touched the ice at the bottom of the hole when the current rises again to abnormal levels. I stop drilling for the second time. All returns to normal.

  ‘Why? What’s going wrong?’

  I check the computer screen very carefully. There is absolutely nothing to indicate that something abnormal is happening 786 metres under my feet.

  ‘Ok, I’ll try one last time. If it doesn’t work, too bad, I’ll bring it back up to the surface. It would be one pass wasted, but better to play safe.’

  For the third time the motor current rises to abnormal values. I stop the cutting and start to bring the drill back up.

  The cable goes under tension, I hear the winch straining, 1.9 tonnes, 2 tonnes, 2.3 tonnes of tension. The winch has given its maximum pulling value. In front of my eyes, the cable has stopped moving. The drill isn’t coming. I try putting some slack on the cable in the hole, once, twice, three times, ten times, nothing doing. The drill isn’t rising.

  ‘Merde.’

  This is serious. The news spreads quickly in the camp. ‘The drill is stuck!’All the drillers are now around me. The cable is at its maximum tension: 2.9 tonnes. Nothing is moving.

  We need to find a solution quickly: the whole season of work is in play. Glycol. We need glycol—antifreeze—which could dissolve the ice chips around the drill that are undoubtedly making it stick. We call the Italian base at Terra Nova Bay where the Twin Otter is just about to leave for Concordia, loaded and ready to take off with four astrophysicists on board.

  Our four colleagues are summarily disembarked and replaced by the barrels of precious liquid. Five hours later 800 litres of pure glycol arrive at Concordia. We tip 500 litres of glycol into the hole. After the first try nothing happens. After the second try, 12 hours later, the tension on the cable drops very rapidly. Hope returns to the team. Spirits rise. The drill also rises but only by 2 metres before it stops again. Huge disappointment.

  We try to help the drill by shaking the cable back and forth, sending waves down its entire length. All these attempts are in vain. The only hope is to wait for the glycol to do its slow job and dissolve the chippings. That could take weeks or even months.

  Most of the scientific team is now redundant and returns home. A small team of drillers and a few scientists will wait until the end of the season, just in case the drill frees itself If not, we will have to come back next season. All scenarios are possible. The drill is free and we can carry on. The drill is still stuck and we have to start again with a new hole at the surface. In any case we will need more money. Assuming the European Community continues to have confidence in us!


  That drill never moved again. It lay there still, nearly 3,000 feet under the ice, not far from where we were standing now. Laurent and his depleted team spent the last disconsolate weeks of the season trying hopelessly to free it. Two seasons of effort and hundreds of thousands of euros poured into a deep dark hole. And then they had to beg the money and time to bring a new rig in and start again from scratch. Luckily the European Community did continue to have confidence in the team, and the project. Everyone knew that this kind of work was hard. But still, you could tell that Laurent’s pride was sorely wounded. It wouldn’t happen again, not on his watch.

  The new drill was now about to re-emerge. The two Italians—Sergio and Saverio—headed out into the cold outer tent and started lifting up a line of trapdoors. Beneath these, they had dug a long narrow trough in the snow perpendicular to the drill. The part next to the hole was perhaps six feet deep, but as it moved outwards the trench grew shallower until it reached the surface about thirteen feet away.

  At first this puzzled me, but as the drill’s head finally poked up from the hole I understood the logic. With the various barrels, the motors, drivers and all the paraphernalia, the drill was more than thirty-two feet tall. If they had had to bring it up to its full height at the surface the tent would have had to be twice as high, and the procedure would be ten times more unwieldy. Instead they simply levered it until it was lying on its side. The top part swung down behind the rig, the bottom part swept up through the trough in the snow and the two men quickly replaced the trapdoors and pulled in wooden frames for the drill to rest on horizontally.

  We all approached the bottom part of the drill, the business end where the cutters were and where the ice core was supposed to be. It was dripping clear fluid from its jaws, but as everyone already suspected there was no core. Above the core barrel, though, was another chamber where ice chippings were guided by spiral channels, and this one was almost full. That was the problem right there.

  Laurent decided to do a cleaning run, not to cut any core but to remove the interfering chippings. He saw me looking wistfully at the machines: ‘Do you want to do this run?’ I slid quickly into the driver’s seat before he could change his mind.

  He showed me the controls. There was a huge red emergency stop button (‘feel free to press this at any time’); a knob to control the cable winch speed; a switch to trigger the cutters and turn them back off. I practised twiddling the knobs and watching the computer screen. Then through the windows I saw a nod from Sergio outside and started the winch slowly, watching the numbers and coloured lines rolling past on the screen. Outside, the drill swayed a little from side to side before Sergio grabbed it and steered it safely into the hole. Technically, since I was driving it was my job to make sure he closed a small trapdoor afterwards so nothing could fall in and wreck the drill. But he had done this many times before and I kept my attention on the cable speed, which I was now allowed to ratchet up.

  Over the next hour, the drill continued its progress downwards, though at one point Laurent chided me gently for letting it go too fast. The whole system was much more skittish than I expected, like a nervous horse. Small tweaks had big effects, and that was before you started factoring in the places the team had already encountered where the ice was brittle, or soft, or just plain ornery. As instructed, I carefully stopped the cable when we were sixty-five feet above the ice, then restarted, inching slowly down to nine feet. Now I could start the cutters, dislodging the chips so they could be safely steered up to the chip barrel.

  I flicked the switch, and then asked Laurent the question that had been bothering me. This whole thing was becoming difficult and potentially dangerous. So why didn’t he just stop, with more than 10,000 feet of ice safely recovered? He didn’t want to, he said, nobody wanted to. There was still more ice to be drilled. The deeper they went the older it was, and the more likely it could tell us an important new part of the Earth’s climate story.

  And so they kept on trying whatever they could think of. One cognac bomb. Two cognac bombs. Alcohol that was more diluted. Alcohol that was more concentrated. Pure alcohol. (‘Perhaps we should try real cognac,’ Saverio said, as Laurent recounted this litany.) They had even tried grease, though Laurent was a bit reluctant—and he drew the line at any other lubricants. It was important, he said, not to mess up the hole by throwing in any old junk. And it was also important to keep cleaning it of the ice chippings and alcohol that had started to clog up the bottom. (Though it might seem shocking to be pouring all these chemicals into the pristine ice, everything up here on the plateau would eventually slide down to the sea and break off as icebergs. Antarctica had its own internal cleaning mechanism. It was only a matter of time.)

  The drill continued, chewing the chips and spitting them out and up. I had to watch the current. If it rose, I’d have started cutting ice instead of chippings and must immediately stop. And there it went. I flicked the switches to stop both cable and motor. ‘Sorry,’ Laurent said, ‘you’re not cutting any core on this run.’

  I know, I know. And yet, for some reason, I was reluctant to stop. Perhaps I was also beginning to understand a little of why these guys were prepared to come to this place to spend days and nights in this freezing tent, fiddling with tiny screws in ungloved hands, heaving this massive steel barrel (with a core inside, the lower, detachable part of the drill weighed as much as a hefty human), enduring frozen fingers and aching backs and legs, and then staring hopelessly into yet another empty barrel, before re-prepping the drill and starting all over again. Just like the meteorites, it was a kind of treasure hunt. There was ice down there and I wanted to get it.

  I said nothing, but Laurent had clearly noticed. ‘Be careful,’ he said, ‘it’s a drug.’

  It also took an inordinate amount of patience. We had to wait another hour for ‘my’ run to re-emerge. (And I was proud to note that the barrel was suitably crammed with chippings.) Then the drillers prepared a couple of cognac bombs and set the drill up for a real run.

  As it descended I wandered off in search of food. When I returned, everyone was crowded round the computer in the small hut. It seemed they had been cutting, or at least they thought they had. Now was the moment to stop the blades from spinning, and heave on the cable. This should activate the ‘core dogs’, teeth that shot out and helped snap the ice cleanly across so that the core segment could be brought back up to the surface. I watched the figures with a newly knowledgeable eye, as the tension on the cable mounted then abruptly fell and the drill started rising. Looking good. And then, nearly an hour later, the head of the drill appeared in the hole, and the team moved into action, lifting up the trapdoors in the floor of the tent, lying the drill on its side and levering it up and out of the trough. This time, too, it was dripping with clear fluid, but as the end swung up into view it gleamed with a cargo that was rather more precious than diamonds.

  There was an ice core.

  We couldn’t remove it yet, though. First the core barrel had to be detached from the rest, have cords tied around it at either end and then be heaved up and over to a temperature-controlled oil bath where it would sit until its own temperature had steadied. Laurent told me that the ice was near freezing point at the bed but had travelled up through ice, and drilling fluid, that grew colder and colder until it reached -60°F. For the ice, that would have been a tremendous shock. It needed to be gently warmed to a temperature closer to the one it was used to before it could be removed and studied.

  And, then, the team opened the lid of the bath, heaved up the barrel and used a wooden pole to push the core out on to a waiting holder on the bench. It was gorgeous: a perfect transparent cylinder, about a metre long, cut through with large crystal boundaries that were clearly visible as if through a window. It had never before been seen by human eyes. It was the oldest part of the oldest continuous ice core on Earth. I put my face close to it, careful not to touch, holding my breath.

  Laurent, standing behind me, contemplated it with satisfa
ction. ‘Don’t ask me why this one worked while the others didn’t,’ he said. And then he turned to prepare for another run.

  Now the ice was playing ball. Over the next day the team brought up another core and then another. They were getting perilously close to the bedrock. Dorthe Dahl-Jensen, a professor at the University of Copenhagen, was the current chief scientist for the drilling and she was starting to worry. At some point above bedrock the ice tipped over the edge from solid to liquid. There was at least a pool of water, which might be part of a whole system of under-ice rivers and lakes. They couldn’t afford to contaminate it with drill fluid, just in case. Perhaps it represented a whole new ecosystem. Perhaps there was something that they shouldn’t contaminate.

  Laurent wanted to keep going; Dorthe wanted to stop. And then the decision was taken out of both of their hands. There had been no warning. But on 21 December news spread through the camp faster than fire. The drill was stuck!

  It was the same old story, a horrible echo of that day back in 1998. A perfectly normal run ended with a lurch in the motor current and however hard it pulled the cable couldn’t help. Maximum tension. No effect. At least this time there was glycol ready to hand. Laurent sent solid chips of it rattling down the hole, clanging against the cable and then sinking slowly down in the fluid. All there was to do was wait.

  The hours passed, slowly, with the cable still pulling at maximum strength. One, two, three . . . after four hours, the tension on the cable spontaneously dropped. Gingerly, Laurent took the controls and raised the tension again. And, miraculously, the drill rose.