Professor Kenji Yoshikawa travelled 3,500 miles by snowmachine. He traveled to Shaktoolik (poplation 223), Koyuk (population 299), Holy Cross (population 204), and a hundred other villages scattered across Alaska. Make no mistake about it: 3,500 miles on a snowmachine is no picnic. The snowmachine is only marginally superior to the pogo stick for long-distance travel. Its suspension converts bone-breaking bumps to bone-jarring bumps. To claim that a snowmachine’s fairing blocks wind is to claim that a sieve holds water. Seasoned riders welcome the insulation of an ice-covered beard.

“I go by snowmachine,” Kenji says, “because the kids like it.” And so he arrives in villages normally reached by bush plane, a stranger with a heavy Japanese accent showing up in the twilight of a winter afternoon with a supersized snowmachine towing a sled full of drilling gear. The kids, Kenji says, like the big machines. His arrival becomes an event. He finds the principal of the village school, or a teacher, or a school maintenance man. Between them, they pick a spot near the school. Kenji assembles his drilling rig. He fires up its motor. His drill bites into frigid earth, into permafrost. In most of these villages, the ground below three feet of depth has not thawed in at least twenty thousand years. Some of it has not thawed in more than thirty thousand years.

The first three feet of ground, called the active layer, lies on top of a hard foundation of frozen earth, hundreds of feet thick. The active layer thaws each summer. As Alaska warms, this thin veneer of thawing ground will thicken. When it thickens, foundations will be compromised. Homes will slowly sink into the ground. Roads will collapse. Surface waters will drain into newly thawed soils. “The kids in the smaller villages have seen permafrost on eroding river banks,” Kenji tells me. “Some have seen it when they dig holes. They see it in graves.” What they see is exposed ice lenses and vertical wedges of ice, frozen ground water, water that seeped into the ground and then froze in place when mammoths wandered the surface.

When he drills, Kenji passes around handfuls of frozen earth. “The children feel it melt in their hands,” he says. “They feel the moisture.”

He lowers temperature recorders into the hole. Over five years, he has set up more than eighty permafrost observatories next to schools scattered across the far north. Kenji, along with everyone else who understands permafrost and climate change, expects the ground temperatures to increase. But this will not happen quickly. So far, most of his holes have not warmed at all. A few have warmed by a tenth of a degree. The kids need more action. He drills a second hole, this one going down only a few feet, just through the active layer. He inserts a clear tube full of water, a frost tube. In spring, the kids will see the water in the tube melt. In autumn they will see it freeze. If there is heavy snow insulating the ground, the frost tube will stay frozen longer in spring or freeze slower in autumn.

Follow up messages from teachers are not uncommon: “December 2nd the frost tube read 34 and the snow depth was 40 cm. The grade 8 students can’t wait until it’s their turn to go out and take the measurements, even when it’s very cold outside.”