Wind blew dust past the yellow tents in our high camp on Kilimanjaro.
“We don’t want to go up,” came a voice from within a closed tent.
Julius and I stood outside, packed and ready. Our two clients refused to emerge from their tent. Perhaps they were bickering again. Or making up.
Reflexively, Julius and I set off on the acclimatization hike we’d planned for the clients, aiming to walk a few hundred meters higher to an abandoned hut. Our alternatives would fill only part of the day. Julius could find an outcrop with cell service and talk for hours to his large family. I could find a rock sheltered from the wind and read glaciology papers on my tablet.
About an hour into the hike, we paused.
“At this pace, Julius, it’s only another two hours to the crater rim.”
Julius beamed. He’d done the same math.
At six-foot-four, Julius Ihonde stood half a head taller than the porters who rose to greet him when he walked into camp. He was lean, almost always clean-shaven, and prayed, head bent, before hiking. He was two years my senior and, like me, had spent his working life in the mountains. Mostly this mountain. He had summited Kilimanjaro more times than any other Tanzanian guide, but when asked the number, he shrugged. He hiked with a scarf over his mouth and a rain cover on his pack. At the end of the day, he whisked dust off his boots and gaiters with a small straw brush.
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I didn’t bother much with cleaning off the dust. It was my first trip to Africa, my first time on Kilimanjaro. My summits had been mostly lower, steeper peaks. Here on Kili, guiding for an American company, I was to watch over two clients: Tom, a wealthy real-estate developer, and Linda, a non-profit administrator.
Kilimanjaro may have been one of the first mountain names I ever knew, thanks to the famous, slant-rhymed title of Hemingway’s “The Snows of Kilimanjaro,” which I read in high school. Hemingway’s mountain is “wide as all the world, great, high, and unbelievably white in the sun.” But it was not a peak I had hoped to climb. It was non-technical, a volcano standing alone above yellow-grassed savannah, a tourist attraction.
The peak, or its glaciers, had also starred in the scientific literature I read while studying glacier-mass balance in graduate school. The Kilimanjaro of that literature was darkening. Eighty-five percent of its glacial ice had returned to dust, scree, and stone in a century.
The changes on Kilimanjaro made it an exemplar for climate change, its vanished ice seen as evidence of a warming world. But high-altitude tropical glaciers, like those on Kilimanjaro, aren’t typical of the world’s glaciers, most of which exist at lower elevations in places with distinct cold and warm seasons. Kilimanjaro’s summit is high, cold and dry, with no winter season. Night and day temperatures vary more than seasonal temperatures. The processes dimming Hemingway’s unbelievably white peak had to be more complex than just a few degrees of warming. When the offer to guide Kilimanjaro came up, I took it. I had to see this icon on the horizon firsthand.
On our trek in, when we were still low on the mountain, Tom had stopped and tilted his head and his wide-brimmed leather hat back to look up at the big-leaved trees above the trail. The branches above him cupped terrariums of ferns, orchids and epiphytes. He smiled, which he did often.
“What’s that one?”
Usually he nodded at the genus name. This time, though, he noted that he had had a tree like it planted in the atrium of a skyscraper he built in San Diego. Climbing Kilimanjaro was his idea of a break between raising office towers. At night, I heard him reading out loud to Linda in their tent. I liked him.
As we had climbed higher, into the moorlands and then into the dusty highlands, Tom had fewer questions. The treeless landscape seemed not to stir him. Maybe he saw nothing familiar, nothing that could be cultivated.
At a notch in the crater rim, Julius struck a pose for my camera, arms outstretched, grin bright in the shadow from his hat, one foot resting on the post of a brown and yellow sign that announced “Gilman’s Point 5,680 meters.”
We crossed into the caldera and followed a trail that traversed under a series of crumbling cliffs. The crater floor, a few hundred feet below, was empty except for a white, warehouse-sized slab of ice and several smaller blocks scattered beside it, square-cornered as shipping containers. The ice was the remnants of the Furtwangler Glacier. It lay on flat, grey ash, unattached to any part of the mountain, looking as out-of-place as an actual warehouse.
A century earlier, I could have skied from the summit, as did Walter Furtwangler and Siegfried Konig in 1912. They had their choice of descent routes: Surveys that year showed enough ice on the summit to cover half of Manhattan. Now, piecing together all the shards of glacier around us would yield only enough ice to cover half of Central Park. Not so long ago we could have skinned up long, gradual snow slopes and glaciers; I could have descended in a rush of turns, swinging across the fall-line in an even rhythm of scraping and silence as my edges bit and released. Instead, Julius and I stepped up, stepped again and slipped, searching for firm dirt and then sliding on scree as we zig-zagged up a coffee-brown mountain. Even if I’d come sooner, when I was starting as a climber and skier, there might have been enough snow to ski. It might still have been a climber’s mountain, the scree buried by snow and ice that required crampons and technique. It was as if a museum had closed before I’d had the chance to see it.
At the summit, I took selfies of Julius and me, arms over each others’ shoulders, Julius hatless, grinning and waving. We felt warm in light jackets, thanks to the intense sun. But that warmth was deceptive. A high summit near the equator is cold. The mean annual temperature at the summit of Kibo—Hemingway’s “House of God,” or the summit cone of Kilimanjaro—is 20 degrees F. When daily temperatures rise above freezing, the warming is brief.
With such consistently sub-freezing temperatures, not much melts in God’s house. Neither frozen leopard carcasses nor 11,000-year-old ice. The few degrees of warming at Kibo’s summit just isn’t enough to have darkened the peak on its own.
Julius and I left the summit after only 20 minutes. We started down, to return to work.
Kibo’s upper slopes were dry, with no meltwater streams or pools. They looked more polar than tropical, more lunar than terrestrial. Walls of ice rose right out of ash and scree, in abrupt corners of blue-white and brown. The ice stepped down toward the clouds in a strange staircase of smooth terraces and fluted towers, a glacier distorted by Duchamp. I saw no crevasses or bergschrund where the glacier pulled away from the higher slopes feeding it, no sign that it flowed. It was just ice sitting on dark cinders with nowhere to go, except away.
When atmospheric pressure is low, as it is on a summit near 20,000 feet, ice can transform directly to water vapor. This process—sublimation—is what shrinks ice cubes inside a closed freezer. Escaping water vapor dulls the cubes’ edges and wears their faces down. Left behind are almond-shaped slivers in the squared compartments of an ice tray. The conditions at Kibo’s summit—intense sun and cold, thin air—are even more conducive to sublimating ice. Models show that sublimation accounts for most ice loss on the horizontal surfaces of the peak’s icefields and the upper reaches of its slope glaciers. That couldn’t have always been the case, or the glaciers wouldn’t have formed. Some change rebalanced the processes affecting the glaciers.
The descent from Gilman Point was quick. Julius and I bounded straight down the slope in astronaut-on-the-moon strides, plunging our heels into the scree and riding the rubble on one foot after the other as it flowed downhill. Momentum allowed us to recover from wobbles and lurches. It wasn’t skiing, though it was an antidote to the grinding ascent. At one point, I stopped and watched Julius run down to me, jacket open and hat brim flopping, scarf loose around his neck, dust contrailed behind him.
When the slope eased near the bottom, Julius told me it was his 54th birthday, then veered off for a spot where he could call his family. I realized our impromptu climb might have been a way for him to celebrate, a chance to move at his own pace on his home mountain. I continued down alone, enjoying the easy freedom that follows summiting. It might have been my one chance. If Tom or Linda turned back the next day, I would accompany the person down. It was more likely to be Linda. She seemed to be on the mountain to keep Tom close. She hiked close behind him and didn’t ask about the glaciers, trees or wildlife. She questioned where we stopped for camp and why we planned to start in the dark for the summit. When I tried to start conversations, she glared.
Once, when Tom and I found ourselves alone on the trail, he turned to me.
“She’s an acquired taste.”
It felt unfair to agree.
Tom continued, “I’m losing my taste.”
Linda reminded me of clients in Colorado whose first questions were about bears. These men and women bought and sold companies, but they stared blankly when I replied that they were far more likely to encounter a bear on the bike path or in an alley behind a high-end restaurant than on a peak. For them, that didn’t fit; mountains held chance dangers and myriad discomforts, while town was safe. It was disorienting to hear that danger could infiltrate their valley lives. For Linda, Kilimanjaro was a huge mountain with strange trees and windy, cold camps; it posed challenges she could not anticipate or even understand, let alone fix with a phone call or program. It was not a world she could settle into, even for a week. Questioning how we managed the climb was her only defense.
It would be another week before those defenses broke down. When, on a safari after the climb, Linda found out a guide had walked her past a Cape buffalo without alerting her to the threat, she was furious. He was doing it so as not alarm her, and on realizing that, her fury dissipated into laughter and playful indignation.
Descending, I saw the white trail in the saddle below me busy with trekkers and porters. They dropped into clouds hiding the plains below. Clouds might be one key to what triggered the changes on Kibo’s glaciers. A drier climate, with less snowfall and fewer clouds to shield the summit glaciers from the sun, could produce feedbacks that imbalance the glaciers.
Indeed, the climate in the region around Kilimanjaro did turn drier about 150 years ago. With fewer clouds, more radiation could reach the snow and ice. With less snowfall, the snowpack would be shallower and require less energy and time to melt. The surplus energy would be available to ablate the ice below. And with less frequent storms, the glacier surfaces would be dirty with dust. The albedo—reflectivity—would be lower, so the glaciers would absorb more energy to drive sublimation at their surfaces and melting on their walls.
But if melting due to warming temperatures is too simple an explanation for Kibo’s ice loss, so is a drier climate, with greater solar inputs and more sublimation. Kibo’s glaciers have survived long-term regional droughts in the past; ice cores have found 11,000-year-old ice at the base of the summit glaciers and a dust layer marking a 300-year drought. The glaciers have expanded and shrunk over the last 11 millennia, with the glaciers a century ago, when Europeans first climbed and skied the peak, relatively large. Drought may have triggered glacier recession, yet a complex string of direct and indirect changes—only one of which is warming at the Kibo’s summit our era’s mildly warmer temperatures—have chained together to sustain it.
When I reached camp, Linda and Tom were still in their tent. Or back in their tent. I’d been gone a little over five hours. Gusts of wind still blew dust through the camp. Linda and Tom didn’t believe I’d been to the summit. When Julius returned, the porters and junior guides appeared from the huts and wind-sheltered nooks where they’d been killing time and clustered around him. He confirmed my ascent with an open-handed wave in my direction. “A true mountaineer!” he said.
At midnight, as I left my tent, I heard Linda and Tom talking in theirs. She didn’t want to go for the summit. Tom didn’t encourage her. So with my pack lying in the dust, I helped Tom pull on his gloves and adjust his gear before leaving with Julius.
“Get a good look at the glaciers while you’re up there,” I said.
He wouldn’t. At sunrise, when he got to the crater, Tom would be tired and hypoxic. He wouldn’t notice much beyond his struggle to climb higher. On his return from the summit, he wouldn’t mention the glaciers.
Then again, I didn’t look that closely at trees lower on the mountain, the mountain we’d both flown halfway around the world to climb. A mountain that stood over our species as we huddled under acacia trees on the savanna, then left and evolved toward building skyscrapers and skiing.
I watched from the dark camp as Tom, Julius, and several junior guides started off under the light of their headlamps. I regretted not asking Julius about one thing—what changes he’d seen in his hundreds of ascents—then ducked back to my tent for more restless sleep.
Blase Reardon has conducted glacier mass balance studies for the U.S. Geological Survey. He currently works as an avalanche forecaster in Whitefish, Montana, and a mountain guide in Aspen, Colorado.