As the last chair approached, the day’s business reached a sort of equilibrium. Dyer’s Alaska trip was traded for one to Kaslo, British Columbia; Sangster firmed up a cat-skiing shoot at Island Lake Lodge, in southeastern BC, which Crossland would film; and the Oregon volcano segment got shelved, opening up the possibility of a trip to Greenland.

“Mossop’s frothing to do that one,” Sangster said, “because Greenland’s so close to the effects of climate change.”

Mossop was hoping for rain when I visited him on location in Rossland, British Columbia, a small town plastered to a Kootenay mountainside. The film studies grad had spent most of the past two years living out of a truck stuffed full of cameras and tripods, a homemade crane, and several pairs of skis, and his hair was shaggy and unshampooed. While the rest of the town was out on the ski hill, revelling in the fresh snow, Mossop and J. P. Auclair, a darkly handsome ski pro from Quebec, sat forlornly in an empty coffee shop.

A few days earlier, they had begun filming a sequence that would make Auclair appear to be casually skiing through Rossland’s alleys, popping backflips over parked cars while an enormous nickel smelter at the foot of the mountain belched smoke in the background. To Mossop’s delight, it had been raining when they started, turning the snow grey and lending the scene a post-industrial gloom perfect for his purposes; to make it look like one continuous scene, however, the conditions had to hold, and unfortunately the temperature had dropped a critical few degrees.

“It’s puking,” said Auclair with a sigh, gazing out the window at the enormous flakes drifting down.

“Horrible,” Mossop agreed, raising an eyebrow. “We must be the first skiers on earth to be praying for rain.”

Like Sangster, Mossop was reticent about the degree to which a ski movie could overcome the same inconvenient truths attached to virtually every action in today’s industrialized world. “All we’re trying to do is harness the emotion of skiing as a metaphor for tackling climate change,” he said. “One of this movie’s themes is something we’ve called — for no logical reason whatsoever — the White Buffalo. Each of the athletes has a goal in mind at the start of the movie, and we follow them as they try to achieve it.”

One White Buffalo brought them to Puyehue, the Chilean volcano that erupted last spring, disrupting air traffic across much of South America. A year and a half earlier, Mossop and Sangster had taken a small crew of skiers there, riding horses to a cabin at the foot of the volcano. After several days of blizzard, a full moon finally emerged from behind the clouds, and they skinned to the summit in time to film the athletes skiing into the crater at dawn.

“So you take that emotion of approaching something extremely challenging, something you’re not sure you can make happen,” Mossop said, “and then, all of a sudden, you’ve done it. The movie builds the Buffaloes up, one beside the other, and ends with all these simultaneous climaxes. That’s what we want the audience to feel.”

The snowflakes were getting heavier, so Mossop and Auclair left the coffee shop and headed to “Suicide Hill,” a steep blind corner in the middle of Rossland where they had spent the previous night building a jump. A small gang of teenagers came out to watch as Auclair warmed up with a few relaxed “cork sevens,” off-axis double twists. Playing to the crowd, he grabbed one ski in mid-air. Had he misjudged his takeoff speed or the angle as he left the jump’s lip, his twenty-metre arc could have sent him onto the concrete or into the tree trunks instead of onto the narrow, hand-shovelled landing ramp. But he touched down easily and noiselessly, to the nodding approval of his fans.

I joined Mossop, who was searching for the best camera angle at the bottom of the hill. Given all the film’s exotic locations, he said, it seemed funny that I should be documenting a jump on the corner of Leroi and Butte. “But even here, you can see how connected skiers are to nature,” he continued. “They spend all their time focusing on the weather.”

Indeed. Around two o’clock, the mercury breached zero. “Green light,” cried Mossop from a neighbour’s porch. Auclair nodded with satisfaction. Finally, the snowflakes had turned to rain.