Antarctica (39 page)

‘We've looked at eight different species and so far they have all been sensitive to small changes. Some of these amazing creatures could disappear before most people even know they're there. And that's a crying shame.'

For the first time since I'd met him, Lloyd's face fell. He wasn't laughing now.

These animals are Lloyd's life, but why should the rest of us care? Well, you don't need to lose many species for it to make a big difference to the ecosystem as a whole. One in particular, a small, shrimp-like creature called krill, is a cornerstone for the entire food web. And it seems to be suffering, too.

Krill depend on the presence of sea ice for their livelihood. They eat the algae that grow under sea ice, and their own young also hang out under the protection of the ice in great krill nurseries. But with the recent warming has come melting. And in a study of nearly 12,000 net hauls from the krill catches of nine different countries, going all the way back to 1926, researchers have found what they describe as a ‘significant' decline in numbers.
¹⁶

That in turn appears to be having a knock-on effect on the charismatic creatures—many seals, whales and penguins—that rely on krill for their food. Already, numbers of chinstrap and Adélie penguins are falling on the Peninsula. Their staple foodstuff is disappearing, and so are they.
¹⁷

Of course there are winners as well as losers. But in this case, the winners moving in to take over the ecosystem are dismal creatures called salps, which are formless gelatinous blobs that are palatable to almost nobody in the higher echelons of the food web.
¹⁸
Taking out chinstrap penguins and Adélie penguins and perhaps seals and whales, too, and replacing them with salps is probably a good thing for the salps. For the rest of us? You decide.

And there's another alarming change afoot. Until recently the waters of Antarctica have been the most isolated in the world. When the ice first came to the continent tens of millions of years ago many crushing creatures—such as lobsters and crabs—became extinct, and the prohibitively long swim from warmer climes farther north means they have never been replaced. That left a host of evolutionary niches for the rest of the animals to radiate into.

But now the crabs are coming back. In 2010 researchers sent a remotely operated submarine deep down into a stretch of water just off the west coast of the Peninsula, to scout out any interesting forms of life on the seabed. To their astonishment they found a massive, teeming colony of king crabs, perhaps 1.5 million of them. The first pioneers probably washed in with a surge of warmer water from the south, and now these notorious bone-crushers are poised, ready to descend on an unsuspecting ecosystem that has lost the evolutionary ability to protect itself.
¹⁹

It's no longer necessary to look at thermometers to know that the Peninsula is warming. Change is not just in the air here; it is in the animals, and it's also in the ice. Over the past few decades, floating shelves of ice that surround the Peninsula have been falling one by one, like dominoes. They break apart, shatter into icebergs that drift away leaving open water where before there was none. For scientists it has become imperative to discover whether this warming really is because of human activity, and, if so, to try to predict what will be next.

 

Antarctic ice shelves are highly impressive. You have to sail up close to them to appreciate their size and apparent solidity. The early explorers called the first one they encountered ‘the Barrier' because it dwarfed their tiny ship. There was no sailing past it, no going round.

That was the Ross Ice Shelf, near McMurdo on the other side of the continent, the great expanse of floating ice the size of France where Amundsen set up base and Scott and his men perished. Another giant shelf lies almost diametrically opposite this, stretching out from the eastern side of the Peninsula, like the webbing at the base of the Peninsula's thumb. This is the Ronne Ice Shelf, which covers about the same area as the Ross Shelf, is thicker, and is similarly fed in part by the fast-moving glaciers of West Antarctica.

Every so often, a massive slab on the seaward edge of one of these monsters will flex just a little too much; perhaps the surface crevasses will start to make their way deeper; tides work the ice up and down, making more crevasses, more cracks until, finally, the slab breaks off and sails away, forming one of those tabular icebergs, flat-topped and square-shouldered, the size of a floating city, or even a county.

There are also plenty of smaller ice shelves around the Peninsula proper. They float at the inner end of many of the region's fjords, filling them with icebergs, bergy bits, growlers and all the various debris of the world of ice. By the standards of the Ross and Ronne ice shelves, these are minor players. Anywhere else in the world they would be considered large.

And it is these shelves, on the Peninsula, that have started to alarm scientists by falling apart. The first to go was the Larsen Inlet Ice Shelf, which disappeared in 1989. Then, in 1995, the Prince Gustav Ice Shelf, which draped the narrow channel between the northern tip of the Peninsula and James Ross Island and had been retreating for decades, finally gave up the ghost.

Larsen A, the Prince Gustav's nearest remaining neighbour, was next. It was about 700 square miles and broke apart in January 1995, sending a plume of icebergs into the Weddell Sea. Researchers now looked uneasily at the next domino in the chain: Larsen B, twice as large and presumably more robust. Was it likely to shatter soon?

Larsen B lay fairly far down the eastern side of the Peninsula, and to get there meant traversing the notoriously ice-jammed Weddell Sea. The best way to watch it was by satellite. But researchers itched to get there, on the ground, and see for themselves what was happening.

One of these was Eugene Domack, a sedimentologist from Hamilton College in Clinton, New York. He knew that the Peninsula was undergoing serious change right now, but he was also ready to take the long view. It was possible that this was just some perfectly natural local warming. Perhaps the Peninsula regularly experienced hot flushes that could disappear as quickly as they came. After all, we had only been acquainted with the region for a couple of centuries. Ice shelves might have been breaking and reforming repeatedly for thousands of years, with nobody there to notice.

If he could only get up close to one of the disintegrating ice shelves, Gene thought he had a way to figure out whether the ice had a habit of breaking up like this, or if the recent events were truly as alarming as they seemed. First, he needed to test his model on one of the more accessible ice shelves, on the western coast—which is rarely choked up with pack ice. If it worked, he could then try taking it into the rather more challenging waters of the Weddell Sea.

I joined him on a trial voyage aboard one of the US National Science Foundation's two research vessels, the
Nathaniel B. Palmer.
²⁰
Following our crossing of Drake Passage, we had steamed straight on down the Peninsula, not stopping at any of the islands or bases, not even the Peninsula's American base, also called Palmer, which was apparently one of the loveliest on the continent, though sniffed at by the rest of the people on the programme as being too cushy. We were heading for an inlet called Lallemand Fjord, about a third of the way down the Peninsula, which bore an ice shelf that Gene had his eye on.

Gene was a man in a hurry. The operations on the
Palmer
were on an industrial scale, with massive winches and cables, and it was forbidden to go out on to the back deck without a float jacket and hard hat. If he felt he had to be out there
now,
Eugene would rush up with his clipboard and pen, grab a hard hat out of someone's hand (or, once, off somebody else's head), and cram himself into the nearest float jacket even if it announced its size as SMALL in large letters on the back.

But at least he was still prepared to go along with one of the oldest Navy traditions. The previous night, the ship had sailed past the invisible line in the sea that marks the Antarctic Circle, and those of us who were first-timers had had to undergo an initiation ceremony. Originally this only applied to crossings of the equator, during which naval ‘pollywogs' (neophytes) were transformed into ‘shellbacks' (veterans) by means of the sort of humiliations that would make members of a fraternity turn pale. Scientific cruises take this at least as seriously as naval vessels, and I know otherwise rational researchers who, when departing on an equator-crossing expedition, would rather forget their passports than their certificate saying they have already paid suitable obeisance to King Neptune, and don't need to do so again.

Luckily for those of us on board who were Antarctic Circle pollywogs, our local King Neptune, biologist Rob Dunbar from Stanford University, had decided to let us off lightly. Instead of the compulsory haircuts and random shavings, or ceremonial dumping into vats of rubbish, he demanded that we each write a poem demonstrating suitable deference to the king.

That evening, after handing in my ten verses of doggerel, I received a certificate stating in elegant copperplate that, at two bells of the first watch of the day, I

 

Did, Boldly and Without Trepidation, Cross the Antarctic Circle at 66° 33' South Latitude, 67° 36'West Longitude, aboard the Vessel Nathaniel Brown Palmer, entering the Treacherous and Unforgiving Reaches of the Antarctic Ocean. By so Doing and having Subsequently displayed proper Obeisance to King Neptune and his Faithful Lieges prior to Departing the Southern Reaches, She
now Commands due Honor and Respect from all Persons, Whales, Seals, Penguins, Fishes, Crustaceans, Sponges, Insignificant Microscopic Creatures and other Denizens of the Polar Domains.

 

(Rob studies insignificant microscopic creatures, which is probably why they made it on to the list.)

Below all this, just above the signature of King Neptune, it added:

 

She bears this Distinction with Pride for it is neither Lightly Undertaken nor Easily Attained.

 

Certificate in hand, I watched for a while up on the bridge, but there was little to see but monotonous grey water with the occasional flash of a distant iceberg on the radar screen. Eventually I stumbled off to bed, to be woken next morning by my cabin mate, Mary, urgently shaking my shoulder. ‘Get up!' she said. ‘You've got to see this!' She was right. While we'd been sleeping the ship had turned into the mouth of the Lallemand Fjord and we were now about halfway along.

The scene was spectacular. All around us there was ice: the great squared-off tabular bergs that had only recently broken off; medium-sized ones with rounded edges and longer histories; and small chunks, with odder shapes. You could see what you wanted in these natural sculptures: a mermaid, a horse's head, swans with their necks entwined, dragons.

But their shapes also told real stories if you knew how to read them. With a practised eye you could see where, as they had melted from below, they had become repeatedly unstable and flipped over and then flipped again. There were shelves of ice jutting out in mid-air, where old water lines had once been, or sides rippled with lines created by bubbles of air that had once escaped from the melting ice below the water, and bobbled their way to the surface.

All of this ice had come from the land, from snow, turning to ice, turning to glaciers, spilling into the sea, floating, flexing and finally breaking off. But the water, too, was freezing. Here it was slushy with grease ice, or frazil, which slithered against the ship's hull; there it was so still that it had already begun to form pancakes, like frozen water lilies, decorated with streaks of snow. As we continued, the sea ice became more abundant, and thicker. The
Palmer's
bow now smacked with pistol cracks as she performed a stately slalom through the pack. And overhead snow petrels wheeled, silhouetted against a slate grey sky, graceful as swallows.

At last, the ship heaved to. Ahead a cliff of ice blocked the way, standing perhaps sixty feet above the water and much more below. This was the Müller Ice Shelf, the parent of all these icebergs, the end point of the waste-disposal chute that was perpetually carrying snow from the mountains of the interior back down to the sea.

The Müller Ice Shelf was to be Gene's test case. He already knew that it had retreated and re-advanced perfectly naturally in the past, and he believed that the signature of this was there to be read, in the mud of the Lallemand Fjord's sea floor.

This mud had accumulated week by week, year by year, from a steady rain of debris through the seawater. Just as with the ice cores, looking down through the layers of this mud was like looking back in time. It contained dirt and ground-up rock carried from land by the glacier, and dead bodies and excretions of tiny sea creatures living in the water, and the relative proportions of land dirt and water creatures could show the times when the ice shelf was hanging overhead, and the times when it was gone.

But first, we had to collect the mud. The crew and science team heaved a square metal tube over the side. It was three metres long and had a heavy weight on the top and when it finally reached the sea floor it sank gently into the soft sediment, collecting a long plug, before being heaved back up and winched on to the ship.

Down below decks in the labs, the core lay out on a bench ready for its autopsy. Amy Leventer, from Colgate University in Hamilton, New York, pored over it, meticulously comparing each layer against a rock colour chart. ‘5Y 4/4 moderate olive brown,' she said, and a graduate student noted it down. (All of the researchers were so familiar with this chart and its arcane nomenclature that they couldn't resist practising on other objects, too. Rob Dunbar had already identified the precise shade of my coat. I'd have called it beige, but he assured me it was ‘light olive grey, 5Y 5/2'.)