One Sunday last November, while 10,000 people encircled the White House to protest the Keystone XL pipeline, judges at the Banff Mountain Film Festival were giving an award to a powerful documentary about a less well-known pipeline.

As the camera pans away from the glare of the rising sun, jagged white and blue ice peaks fill the screen. The tallest catches the first pink light of dawn. In the foreground we see a climber encased in his red down survival spacesuit. He is walking very, very slowly, inching up a steep knife-edge ridge toward us. As the scene shifts to slow motion, we can see that he is stumbling.