Probes beneath the ice could shed light on the fate of the world’s coastlines. Illustration by Owen D. Pomery

Most of us do not spend much time thinking about what is happening there, but Antarctica’s future is now very much entwined with the future of the rest of the planet.  All of us. So, thanks to David W. Brown for this travelogue:

Journey to the Doomsday Glacier

Thwaites could reshape the world’s coastlines. But how do you study one of the world’s most inaccessible places?

I first saw our icebreaker, the RV Araon, when we were due to leave for Antarctica. The largest icebreakers are more than five hundred feet long, but the Araon was only the length of a football field; I wondered how it would handle the waves of the Southern Ocean, and how it would fare against the thick sea ice that guards the last wilderness on Earth. Its hull was painted a cheerful persimmon color, and its bow was conspicuously higher than the rest of the ship, with a curved shape suggesting that icebreakers don’t so much carve through ice as climb and crush, climb and crush. It was January 3rd, summer in New Zealand. In the heat, ice was a little hard to picture, let alone icebreaking.

Our voyage would last two months. We would spend a week or so sailing from Christchurch to the edge of Antarctica, then break through the pack ice of the Amundsen Sea, before arriving at Thwaites Glacier—one of the fastest-retreating on the continent. Our expedition was led by the Korea Polar Research Institute, which had brought some forty researchers from around the world to the Araon. They would have a month at Thwaites to conduct their respective research projects before the return trip began.

I had been “on the ice,” as Antarctic explorers say, once before, in 2019, while researching a book. There’s no room for passive observers on the most remote expeditions, and so, on that trip and this one, I’d signed on as a field-research associate, sponsored by the University of Texas Institute for Geophysics and the G. Unger Vetlesen Foundation, an Earth-science nonprofit. For the second time, I would be working alongside Jamin Greenbaum, a forty-two-year-old scientist at the Scripps Institution of Oceanography, at the University of California, San Diego. We’d be hurling torpedo-shaped probes from a helicopter into cracks in the ice, with the aim of studying the warm ocean water that is melting Thwaites from below.

We had successfully placed sensors in the water during our first expedition, on the eastern side of the continent, throwing them from the back of a refurbished cargo plane from the Second World War. We weren’t sure we could repeat this feat. Weather on Thwaites is notoriously hostile, and, because dense cloud cover makes satellite reconnaissance virtually impossible, we wouldn’t be able to identify promising fissures until we were flying over the ice. Greenbaum’s style of adventure is less romantic than world-weary. “Antarctica occasionally lets you pull something off,” he told me. “But not often.”

The continent is shaped like a hitchhiker’s fist, its scraggly thumb pointing west. Thwaites, which is named for a late, eminent geologist, is on the southern side of the thumb, where it meets the hand. There are bigger glaciers elsewhere in Antarctica, and they are also showing signs of weakness, but Thwaites is especially concerning. Its adjoining ice shelf—a large floating expanse of ice, which extends from the glacier out over the water—acts like a cork in a wine bottle, holding much of the rest of the glacier in place. If the cork decays and gives way, the glacier could begin to flow rapidly, and eventually it and a larger stretch of surrounding ice in West Antarctica might slide or calve into the ocean. Thwaites is often known as the Doomsday Glacier, because, in this worst-case scenario, sea levels could rise by several feet or more, inundating many of the world’s low-lying coastlines.

Thwaites is already retreating—that is, it is shrinking, as more of its ice flows into the sea. Glaciologists and geophysicists want to figure out whether a colossal “retreat event” is likely to happen in fifty years, a hundred years, or five hundred years. To investigate the situation, our expedition would explore Thwaites by land, sea, and air. The Araon had seawater laboratories, underwater probes, and two helicopters; it also carried drones, snowmobiles, a disassembled hot-water drill, Zodiac watercraft, and a subsurface glider—a kind of robotic dolphin—that could take seawater measurements autonomously. Yet all of this would be useless if we couldn’t get to Thwaites, which is one of the least accessible places on the planet. To reach the glacier by air, you must first travel overland to construct an improvised airport. Go by sea, and there’s a good chance that your ship will get overwhelmed by ice and be forced to turn back. David Holland, a mathematician and an Earth scientist at New York University, and a member of our expedition, told me, “There are many bad ways to do this, and we’ve found all of them.”

The Araon’s science crew included three researchers—Lucas Beem, a geophysicist; Jamey Stutz, a geologist; and Christopher Pierce, a graduate student in engineering—who would fly in a specially equipped helicopter to scan Thwaites with radar. As we gathered at the Christchurch docks with our luggage, I looked between them, past bobbing sailboats, to where behemoths the size of oil tankers loomed. When I was a kid, my father worked on the Mississippi as a tugboat mechanic and pilot, and I sometimes tagged along as he sailed from the dock near our trailer, in St. James Parish, to the Port of New Orleans and back. I’ve seen big ships and small ones, and I could tell that the Araon was strikingly small.

“Are we sure this is the right boat?” I said, to no one in particular.

There were a few nervous laughs.

“Place your bags on the net,” a Korean dockworker said. He’d covered the ground with thick cargo netting. We set our bags where we were told.

“This way,” another worker said, waving us along like a traffic cop.

A gangplank stretched from dock to ship. Once I crossed, the Araon would be my home until March. I hesitated, then made my way across the chasm.

Earth’s climate system has a single goal: to make the temperature the same everywhere. Hot air and water flow naturally from the equator to the poles. Because heat rises, one might expect currents of warm water to travel near the ocean’s surface, but things aren’t that simple: at tropical latitudes, the sun is stronger, evaporating more water than it does elsewhere, and the warmed seawater ends up slightly saltier and denser. It sinks. Near the poles, warm currents flow beneath cold ones…

Read the whole article here.