Monday, April 17, 2000
The Art of Herding Icebergs
By Kate Laird
Petermann Island, Antarctica
HE 30-KNOT NORTHEASTER had been our ally for two days, but it dwindled after dinner. Milling icebergs began to move toward the inlet where we'd moored Pelagic, the expedition yacht my husband Hamish and I run in South America and the Antarctic Peninsula.
A few inches of new snow muted the cawing penguin colony ashore while Hamish and I motored out in the dinghy. All we could hear was the slap of the swell against the ice as we lassoed the first berg with 150 feet of floating line, then nothing but the roar of the outboard as we tried to shift a block of ice the size of a pair of 18-wheelers (with who knows how much hiding below the surface).
Herding ice is a fairly normal part of sailing in Antarctica. All the ice I'd shifted on two previous visits was small enough to push with the dinghy, but I was skeptical we could move this moster. Hamish, who was on his tenth voyage, reassured me. Slowly, we saw a hint of progress as the iceberg moved against the tide and away from Pelagic.
Whenever someone asks Hamish to name the safest anchorage in Antarctica, he answers, "Six hundred miles away in South America." All the nearby anchorages had been choked with ice when we approached Petermann Island two days before. Ninety-one years earlier, when French explorer Jean-Baptiste Charcot sheltered here through the winter, he and his crew aboard the Pourquoi Pas? strung heavy iron chains across the narrow entrance, but icebergs like these simply snapped them.
Petermann Island itself is a mile long, with a big hill faced with ice cliffs that rose behind us. The inlet is about 50 feet wide, enough to back Pelagic in and center her with four lines tied to rocks ashore under the watchful eyes of a cohort of penguins.
We only had to keep the bergs at bay until slack tide, which we were certain would be in a couple of hours. Meanwhile, we attacked another one.
The third time, I had my head down, monitoring the line whipping out from the floor of the dinghy as we circled the iceberg to form the lasso. "Drop it! Dump it!" yelled Hamish.
While I'd watched the rope, the berg had drifted considerably closer to two others. This one was almost as long as 54-foot Pelagic, twice as wide, and perhaps 10 feet tall in the middle. The swell was magnified inside the triangle of ice, and cold air radiated off the walls. The dinghy sloshed up and down, and I couldn't see a way out.
Behind us, our route had closed off completely, with a foot or two remaining between bergs. The gap ahead looked too narrow. I grabbed for a handstrap as we raced for it anyway, dingy pitching, and squeezed through with a hand's breath to spare on either side.
There are no commercial tide tables for the Antarctic Peninsula, but it was three days after the full moon, so we knew we would have a "spring" (extra high) tide that night, and that the swell would give it an extra boost. But when would it change? We could see that permanent ice onshore was already awash, and when we'd left Pelagic, the depth sounder showed almost a meter more water than we'd noticed in the previous days.
We shifted another berg, then returned to our first one to give it a pull. After midnight, one of the six New Zealand climbers on board offered to take my place for some herding. I crawled back into my bunk, but didn't dare to take off my thermals. If the ice grounded out at the height of the spring tide, we might be trapped inside for a month or more. I left my foul weather trousers rolled down around my boots like a firefighter and hung my jacket on the door instead of in the wet locker.
I had a hazy hour's sleep, although I could still hear the dinghy's occasional roar. Then it came alongside and I heard the thump of Hamish's boots on the companionway. At the sound of Pelagic's pre-ignition alarm, I sat up and slid my feet into sea boots. By the time the diesel turned over, I had the trousers all the way up and the shoulder straps on.
One of the bergs had parked on top of our anchor: We'd have to abandon it and its 100 meters of chain. I'd read about "slipping" anchors--it's a favorite trick in Patrick O'Brian novels--but never had to do it before. Hamish secured the loose end of the chain to a rock before I kicked the working chain out of its brake on deck. Instantly, one of our most important pices of safety gear snapped over the side and vanished. No bubbles, scarcely a splash.
But we didn't have time to linger. Hours after we had expected the tide to turn, it was still rising, with the added push from the swell, bringing the ice faster than we could shift it. At the rate the bergs were moving, we might have five minutes before the door shut completely. We heaved the four shorelines aboard and piled them untidily on deck. As soon as the water was clear, Hamish started for the gap, iceberg to starboard, rocky shore to port.
Pelagic's centerboard keel lifts on a five-to one block and tackle and a truck winch such as you might see on the bow of a Land Rover. I had the remote switch in hand and began to lift the keel as soon as I felt us hit bottom.
The iceberg continued to close the gap. The pressure of 30-ton Pelagic wasn't enough to make it pause. The truck winch wasn't lifting the keel fast enough, but Hamish didn't stop to let it catch up.
The keel slammed off the rock bottom, and hit again. The noise was horrific: seven tons of steel and lead colliding with rock. But the keel was built for this sort of abuse. It simply pivoted on its pin, presumably with less paint on the bottom than before.
The danger was the unstoppable ice to starboard. Would it close the gap before we made it through? Would it trap us against the shore? Was there enough depth where we were going?
The boat was crawling, but with each slam of the keel shuddering through the hull and the rig, it felt as though we were at full throttle. Then we went for a few seconds without a hit. One more quiet thump, then nothing. We were through. The depth sounder showed we were back in eight meters. Ten ... Fifteen ....
We rolled the four shorelines onto their spools on deck and hoisted one of the two spare anchors into place on the bow. Back to normal. It was 2:30 in the morning; we'd missed the moment when the Antarctic "sunset" blended into "sunrise," and it was light enough to read on deck.
We motored away from Petermann toward another anchorage two hours away. Behind us, the ice was still moving in. By five a.m. we were snug in Stella Creek, not sure if it was time for breakfast or for bed. It proved to be another quiet day. We walked over the glacier, watched skuas fly acrobatics above us, and then everyone spent the afternoon near the diesel heater, reading, baking bread, and napping.
But at 2:30 a.m., the anchor watch came down to knock on our cabin. "Hamish? Kate?" she said, "Sorry to wake you, but there's a lot of ice coming in ..."
© Kate Laird, The Wall Street Journal 2000