KOTZEBUE — It’s spring here, sunny and bright, and deceptively cold. Outside it’s minus 7, with a west wind off the sea ice drifting snow and torturing the frozen air, creating fog out of clear blue sky. The sun glints on falling crystals and the endless white snow. My fingers are cracked, my nose sunburnt and frosted, and, as usual in spring, I’m packing while also still unpacking — tools, rope, mittens, muktuk and dried caribou — after weeks guiding NASA and Southwest Research Institute scientists at the Great Kobuk Sand Dunes.

In mid-March, we headed upriver with three snowmobiles and four sleds, myself and two other guides from Arctic Wild who I’d never met before, Pat Hendersen and Tim Pappas. They are big, tall, young capable white guys and I had my work cut out pretending I was even one or two of those things.

There’s a lot of snow this year, and I worried about the river above Kiana. It’s often soft and deep, with overflow and sinkholes, not the best place to be dragging heavy sleds without a trail. I had called ahead to Ambler and couldn’t stir my adopted nephews, but my niece, Andrea Kelly, offered to set off immediately, alone, to help pack a trail down the river.

The first 100 or so miles went well. The next hours were harder, with us struggling to get off the river, through willows and trees, and up a steep face onto the snow-covered sand. It was dark and late when we made it to the old Ferguson allotment on Ahnewetut Creek. We pitched tents, and in the morning stepped out into the huge awesome presence of the dunes. It wasn’t a tan sandscape like in summer — virtually no sand was exposed on the entire 25-square-mile surface. It was more like waking up on a cold, white alien planet. Through sparse spruce, just across the creek, a wall with heavy cornices towered against the sky, blocking the rising sun, and to the west, the slopes of taller dunes hid those horizons, too.

For the rest of the day, we prepared camp: making trails, cutting wood and setting up tents and woodstoves for the scientists to arrive the next morning. Tim and I scouted out a long flat inter-dune area for an airstrip, and he headed back to camp to work while I packed a 60-foot-wide and 2,000-foot-long airstrip as requested by Jared Cummings of Golden Eagle Outfitters, to land equipment and passengers in his turbine Otter on skis.

The landscape shifted colors as I snowgoed back and forth, beautiful blues and moody grays shifting under patches of moving sunlight and clouds. Along the northern horizon, the white diamonds of the Brooks Range sprawled, and closer, the Jade Mountains reached against the sky, friendly and familiar. Below the Jades, I could see a tiny line of white, the high tundra where caribou migrate south in the fall toward Onion Portage, and under that a dark line marking the timbered bluff of Paungaqtaugruk, where I was born and raised. It felt strange to be driving back and forth, going nowhere, and staring at my past only 15 miles away. I longed to head home. I pictured my family in my youth, working around our small sod igloo, shoveling snow, checking traps, feeding the dogs, hauling wood and water, and disappearing inside for the night, shutting out the cold as best we could. Was that this same person?

The next day, the feeling on the dunes changed again, with the arrival of people. Eric Sieh, of Arctic Backcountry Flying Service, landed early in his Super Cub to drop off a videographer from Smithsonian’s “Ice Airport Alaska,” who wanted to film the arrival of the NASA and SWRI scientists. Eric is a longtime friend, more than an expert at flying, and as I’d predicted, could land anywhere. Sure enough, he ignored my strip and landed beside it. It was good to see him. We joked and chatted briefly. He was in a hurry to return for the next load.

Jared arrived soon afterwards, touching down with a huge load in open snow. Tim and Pat and I helped him lower down heavy wooden crates, and we sledded loads back to camp while Eric and Jared flew two more trips each from Kotzebue, ferrying eight scientists — four women and four men — and another ton of gear. It was a cold day, with the sun hanging in the sky, and the passengers climbed down unacclimated, unaccustomed to bulky clothing and large boots, moving awkwardly at first, stumbling and sinking in the snow.

I was bundled up in my fur parka and hat, and heard someone say, “There you are.” A woman gave me a hug. A tall man followed, smiling. It was Cynthia Dinwiddie and David Stillman, two remaining members of the NASA project I guided when they first journeyed to the Arctic to study the Kobuk Sand Dunes. I hadn’t seen either since March 2010 when I snowgoed their crew to a ski-plane on the river ice.

Cynthia was the principal investigator, then and now, coordinating this study of movements of dust and sand, and the mysteries of perched water in these dunes, searching for clues needed for any future travel to Mars, I think. She looked the same, pretty, younger than her age, and a little nervous. David, who is tall and ceaselessly good-natured, and deploys robotic projects on the Moon, was an older version of the blue-eyed, smiling young man I’d known — minus a certain amount of head hair. I kept my hat on. I knew I didn’t look the same either. Standing there smiling, I glanced quickly toward the Jades, trying to sort out which years had passed since I last saw these friends, and which were the ones further back.

I remembered Clarence Wood had rented NASA his cabin below Kavik Creek. He was old, though still roaming, and stopped in on his way from Ambler to Kivalina, to have coffee and check what the white guys were up. My lifelong friend and brother, Alvin Williams, was alive then, too, young and handsome, just 43. He brought supplies down, and his 12-year-old son Kituq came along, and his girlfriend, Pearl Gomez. Alvin and I laughed a lot, as we always did, told stories, and discussed animals, guns and our boots. I remember cooking outside on a Coleman (we all hated the cook’s sour, expired packaged food), frying caribou, muskox, lynx, rabbit and ptarmigan for the scientists, and letting them try muktuk. Later, Andrew Greene came into camp with a wolverine on his sled. After the project ended, I headed north to Midas Creek and the upper Noatak country.

Quickly, I rushed to load luggage and red and blue coolers on my sled, to get these nice cold smart people out of the way before Jared’s powerful propwash manufactured a blizzard.

• • •

Things got busy after that, and complicated. We were a big camp. Each scientist had their own specialty, and they moved back and forth unpacking crates of radar and equipment, firing up a generator and a Starlink. Tim and Pat and I had our hands full too, chopping wood, tending camp, repairing things and helping them. We settled in to long work days out in the cold — what I think of as fun.

The weather stayed cold, minus 25 some nights, sunny most days. To me it was perfect, although mornings were not as easy as when I was younger, with my food and water and everything in my tent frozen solid. The scientists had their own difficulties: a hole melted in the science tent, and the first night, the tent with two Davids — Camp David — filled with toxic smoke from air mattresses touching the stove. Pat and Tim were concerned about our first-day trajectory toward fire. Me, I had predicted difficulties; mixing nylon tents and woodstoves takes practice. In my small tent, my homemade stove was ice cold, followed by frighteningly hot. I was sympathetic and loaned the guys my spare mattress and cotton blanket, and kept my caribou hide.

I worked daily with David, setting up radar equipment. Once we had things ready, a researcher named Jani Radebaugh and her cheery young student Emma Gosselin accompanied us criss-crossing nearby dunes and inter-dunes at slow speed, dragging ground-penetrating radar. Over and over, their GPR and Ohm-Mapper units went on the blink (or no blink), and we had to return to camp to thaw things out. Cynthia joined us occasionally, though she mostly had to stay in camp and download data we gathered, to guide the drilling team.

The drill team was having a tough go of it, too, making slow and no progress with a hand auger, until finally Pat had Tim take over more cooking and wood duties, and he worked long hours to help the team get down past caving sand and frozen layers.

I kept hoping to make a trip home, glancing in that direction like a hungry wolf, but every minute was filled, mechanical difficulties plagued us, and Cynthia and David were relentless in their desire for more data. I’d been waiting 15 years for their return, and was relentless, too, in my efforts to make this work out for her and her team.

Morning and evening, we gathered in the chilly meal tent to eat great food Tim and Pat somehow cooked, compared notes, tell stories and plan out the following day’s work. Slyly, I brought along my muktuk and dried caribou, and did my best to hide my bad hip and other infirmities. I’d turned 60 the previous month, and my dad turned 90 while we were there. I was feeling a surprising number of years piling up around me, and more than once, I went ahead and took advantage of my elder status.

“You people don’t respect the cold enough,” I said, after days and days of dead batteries, blank screens, an iced-up generator, snapped wires and other difficulties.

It didn’t appear that anyone heard, or wanted to hear. Nerves were starting to fray. But David began carrying big batteries in his jacket — and in mine — and Cynthia asked me to help drag a GPR unit into her and Jani’s tent to thaw. And slowly our progress picked up.

One day, I overheard Cynthia telling the group that I’d taught her to shoot a rifle and a pistol. Really? She started archery after that, she said. Faint memories drifted back: the Anchorage Museum had shown Cynthia and my photographs; they’d flown us at separate times to Anchorage to present our work. Suddenly, I realized, she’s on the cover of my fourth book! How and when had my life gotten so convoluted that I forgot all this?

“I remember you soldering broken wires on the GPR with a Bic lighter,” David said, smiling. “I don’t know how many times I’ve told that story. We were miles from camp, out in the cold and you fixed the GPR.”

It made me feel good — trusted — and I went out and banged ice out of my sled, to haul one more load of water from the creek. When I was done, I drove to the top of a dune for a few minutes to watch the mountains settle in after sunset. I heard a buzzing. Emma’s drone hovered overhead, the little insect face staring, then the props whirred and it shot north to map another dune.

The land glowed in the evening light. I got out my iPhone to take a photo. I checked to see if the Starlink reached this far. It didn’t. The mixed scene felt incongruous and made me think of my brother Kole and I, reading science fiction novels when we were kids: Kole liked “Dune,” and “The Martian Chronicles,” and Edgar Rice Burroughs books. I read Asimov, but preferred “real” stories. I pictured us brothers skinning muskrats, eating muskrat for dinner, gnawing the boiled hairy skin off the tails. My primitive hunter-gatherer past felt close, and so incredibly distant. Even the concept of studying this ancient sand to try to understand the surface of Mars felt different, and I realized those little boys would have seen this life of mine as a science fiction.

The camp looked peaceful from there. A few stars were out, and I took one more photo of the distant mountains before I headed back down to continue my chores in the cold and falling darkness.

Seth Kantner is a commercial fisherman, wildlife photographer, wilderness guide and is the author of the best-selling novel “Ordinary Wolves,” and most recently, the nonfiction book “A Thousand Trails Home: Living With Caribou.” He lives in Northwest Alaska and can be reached at sethkantner.com.