First observation of Thwaites Glacier by Goodell – Rolling Stone


This is the ninth dispatch in a series by Jeff Goodell, who will study the effects of climate change on the Thwaites Glacier.

At about 5 o'clock in the morning last Tuesday, at 74 degrees 57.4 degrees south latitude and 106 degrees 12.8 degrees west longitude on the far-off coast of western Antarctica, the Thwaites Glacier emerged from the fog and was we. Peter Sheehan, a 27-year-old spiritual researcher and worker at the British University of East Anglia, was one of Nathaniel B. Palmer's first scientists to see it. He had just climbed five stairs from the laboratory to the deck of the ship, where he made sea ice assessments every hour of the night. And that's it: a wall of ice on the starboard side of the ship, looming in the early morning light.

"It was a strange sight: the blue water, the blue sky, the blue ice. Everything was blue, "said Sheehan, who had never been to Antarctica before, stunned by the beauty of this place. He ran to get his camera, put on his coat and headed to the front of the ship, where he found himself alone, one of the very first human beings to have never faced this huge glacier whose fate is inextricably linked to the future of civilization. . "Usually, I have a scientific mind – I'm thinking of how we're going to collect data – but at that point, it was the whole human reaction. I was just overwhelmed by the power and beauty of it. "

Around 7 am, virtually all the Palmer's scientific and support team – perhaps 25 people – piled onto the deck, which looks like a five-level skybox above the main deck , with large windows and a walkway to stroll to the outside. We all had our cameras and iPhones on the outside, taking pictures as we sailed along the steep, high face of the Thwaites Ice Base (the thick layer of floating ice that sank). extends from the glacier like a fingernail). The weather was strangely warm and welcoming, the wind calm, the sea calm. The Palmer has managed to get closer to a few hundred meters from the calving front – an extremely rare thing to do on any glacier, let alone a giant like Thwaites, because of the risk of falling ice. The cracks in the ice shone bright blue. Emperor penguins dipped on an ice floe and swam beside the ship, with astonishing and graceful speed, jumping into the water as if the great ship was a long lost friend.

The tranquility of such icy splendor was sublime. It was also spooky, as if this huge wall of ice marked the boundary of another dimension of time and space.

Getting to Thwaites was not easy. Our passage from the tip of South America to West Antarctic took a month, during which we had gone through great waves, mechanical failures and a medical emergency. But through all of that, there was a sense of mission about our trip, a feeling that we were charged with answering one of the most urgent scientific questions of our time, namely, how fast Thwaites will it go down?

Given the importance of Thwaites' stability for the future of civilization, its history is surprisingly little known. Most scientists believe that since the last interglacial period, which ended about 120,000 years ago, the waters in which we sailed had been covered with thousands of feet of ice. Other scientists suspect that Thwaites has melted significantly during this period, but there is no clear evidence about it. What is clear is that in recent decades, carbon pollution has accumulated in the atmosphere and the world has warmed up. The Thwaites ice floe quickly retreated, opening new waters during the summer on the never-explored glacial farrowing front. or mapped.

Caption: Emperor penguins on the calving front of the Thwaites glacier ice floe in Antarctica Source: James Kirkham

Emperor penguins at the calving front of Thwaites glacier ice floe in Antarctica. Photo credit: James Kirkham

As a result, much of what scientists know about Thwaites comes from satellites. Satellite altimeters measure the height of the ice caps, which can be used to calculate the mass and the melting rate. Gravity inversion technology is used to get a rough idea of ​​the seabed, which determines how ocean currents reach the bottom line of the glacier. But all these data are approximate, full of errors and miscalculations – a shade shadow.

The reality is more accurate and more likely to inspire respect. I was standing on the catwalk with Swedish oceanographer Anna Wåhlin, who had been to Antarctica seven times and thought she had seen a lot of ice in all its forms. But she was visibly moved by her meeting with Thwaites. "We are the first people to be here to watch this," she says, her eyes scanning the blue ice wall. "Already."

Wåhlin is a brilliant scientist, apparently able to keep in his head a fully operational model of the Southern Ocean. And so, naturally, she was eager to get to work by comparing what the satellites had told her about the seafloor contours around the glacier and what she could find out for herself (with the help of Hugin, an automatic underwater surveillance system). vehicle scalloped with the high-tech sensors we had with us aboard the ship): "I want to get some data!" exclaimed Wahlin with an ironic smile as we sailed along the glacier. "I want to start measuring things!"

Wåhlin's enthusiasm was easy to understand: she was face to face for the first time with a new world, a world with many secrets to tell. Charles Darwin, the nineteenth century scientist whose ideas on natural selection shook the world, must have felt the same feelings when he first met strange creatures on the Galapagos Islands.

photo credit: James Kirkham

However, Darwin did not arrive at the Galapagos aboard a ship with Gun N 'Roses' "Welcome to the Jungle" playing on the sound system of the bridge. And no one could confuse the Palmer, a heavily fortified icebreaker with cranes and industrial power winches, with a 19th century schooner. Instead of a big wooden wheel, the second at the helm, Luke Zeller, piloted the ship with what looked like a joystick. Behind us, a black smoke emanated from the diesel engines of the ship. The paradox was impossible to escape: we were a carbon-burning machine that was investigating the impacts of carbon combustion.

On deck, I spoke to Rob Larter, the chief scientist of the trip, who spent most of his adult life thinking and working in Antarctica. "It's more chaotic than I thought," he said when I asked him about his first impressions of the glacier. He explained that most of the Antarctic ice shelves are flat, they look like slices of wedding cake (an iceberg that's broken is so rectangular that it has become so sensational on the internet last year). In contrast, many areas of the Thwaites pack ice are a mixed mess, with large crevasses and sloping shoulders. For Larter, the sloping shoulders of the pack ice meant that there was a lot of melting at the base of the ice cap, which probably meant that there was probably a lot of hot circumpolar deep water which flowed below. Which, if it is true, is not good news for anyone who owns real estate in Miami or another city vulnerable to rapid rise in sea level.

We sailed along the calving face for a few hours, fascinated by the ice wall. "It's like watching a fire," says Lars Boehme, a scientist who tags seals and turns them into ocean research assistants. "You can continue to watch the ice forever." As we sailed, a sonar system in the ship's hull sent out high-pitched sound waves of several kilometers. The ship's computers listened to the echo of the sound waves and translated these variations into colorful maps and in real time of the hollows and undulations of the ocean floor 3000 feet below.

In the evening, the wind had risen and the ship moved away from the glacier face to further map the seabed in the area. People crashed into their booths or basking in the labs, eating ice cream bars. Later, I found Sheehan at his office in the ship 's laboratory, back to work on the ocean chemistry data. I asked him to show me pictures that he had taken early this morning from the bow of the ship. He lifted them on his Mac and flipped through them. In each of them, the wall of ice appeared as a terrifying mine. I asked Sheehan what he was thinking now, watching them.

"It's hard for me to think of something as big, as permanent, as vast, as fragile as it is," Sheehan said. "We associate size and size with a permanence, as if we were looking at a mountain and we said to ourselves:" it will always be there ". But watching Thwaites forces you to realize that this is not always the case. This glacier, as huge as it is, has no permanence. If we come back next year, it will look completely different. Sheehan interrupted to look again at the picture of the glacier. Above his head, just outside the porthole, the real thing was looming at dusk. "It makes you understand that the things you think will always be there might not be. It's a good thing to get an idea.

Read other news stories from Jeff Goodell's "Journey to Antarctica" series

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