The first time I landed on the Siple Coast of West Antarctica, I immediately felt disoriented. The landscape was a monotonous flat white, with wind-scoured snow and ice extending to identical horizons in every direction. In this isolated spot 380 miles from the South Pole, the only point of reference was the pile of bags and crates that would become a camp for three researchers plus myself, a journalist.
Over the next three weeks, the sun traveled circles in the sky. Day and night blended into a uniform snow-reflected glare. Smells disappeared, except for the fuel that we pumped into our snowmobiles. Every direction seemed the same.
Some parts of my mind gradually attuned to this unfamiliar environment, while others—strangely—did not.
During an hours-long snowmobile ride, the horizon that we’d been staring at suddenly opened up, and I realized that we had crested a barely perceptible hill. We zoomed down and down the far side—but after an hour of coasting downhill, I glanced at my GPS and realized that we had only descended 15 feet.
Since that first trip, I have made five more visits to Antarctica, each one lifechanging in its own way. On one occasion, I watched as researchers melted a narrow wormhole through the half a mile of ice beneath our boots, and then lowered a camera—allowing us to peer into a subglacial lake that no human had ever seen before.
But to this day, my first visit to the Siple Coast and the disorientation that I felt still sticks with me: a reminder that some things are too large for humans to see and comprehend.
When I look at a Landsat image captured from space, I can see the Siple Coast in a very different way.
Six massive glaciers, each 20 to 30 miles across, ooze off the coastline and merge into slab of ice the size of France that floats on the distant, unseen ocean. The individual glaciers are marked by lazily curving, riverine flow-lines that extend 150 miles along their paths. These rivers of viscous white molasses are separated by domes and ridges of ice that sit between them.
I once camped on one of those high places, called Siple Dome, and there at ground level I struggled to recognize it as a pinnacle. But when seen by a satellite camera from a low angle, these domes and ridges are large enough to cast shadows.
In the 1970s, scientists landed at dozens of locations on these glaciers and pounded metal poles into the snow. They lingered for 24 hours at each position, getting satellite fixes on each pole’s exact location with an early predecessor of GPS. They returned a year or two later to each site, found the same poles — now several feet shorter, due to the accumulation of snow — and re-measured their positions. In this way, they calculated how far each pole had moved, and in which direction, to generate a rough sketch of how these glaciers flowed.
This monumental feat of grunt-work immediately revealed a major surprise. Five of these glaciers were moving 1,000 to 2,000 feet per year, a speed that is common in large Antarctic glaciers. But one of them, Ice Stream C, was flowing at only about one-fiftieth that speed, 20 to 40 feet per year.
The surfaces of the other glaciers were scattered here and there with crevasses — the cracks that form as a glacier slides, bends, and stretches over the uneven bed beneath it.
But Kamb had almost no crevasses — because it was barely moving.
