Chasing ice: glaciers in retreat The combination of the film's majestic settings and its engaging subject is compelling. As a photographer Balog had long ago realised that the most powerful issue of our times is the interaction of humans and nature. He spent years photographing endangered animals and big game hunting for a book called Wildlife Requiem. But I realised that the big issue wasn't about preserving faraway wilderness habitats, it was that humans are this huge all-pervading influence on the land, and when we collide with the wilderness it provides an incredibly rich field of photographic exploration. It was during the New Yorker assignment in 2005 that Balog became obsessed with glaciers. The story, he realised, was in the ice. Balog's photographs are not benign - aquamarine bergs bathed in a soft glow - but voluptuous and visceral; he makes the ice live. Indeed at one point in the film he regrets the passing of a glacier as if it were a person, mourning for "a sense of the glacier coming to the end, like a decrepit old man falling into the earth and dying..." James Balog grew up in Colorado. A tall, fit man who looks much younger than his 60 years, he says that as a boy he was always passionately engaged with the outdoors - hiking, camping, climbing trees and acquiring animals. When he was 18 he became fixated on alpinism and mountaineering. He took a master's degree in geomorphology (the study of land forms), specialising in mountain environments, and did a lot of climbing in the Himalayas, the Andes and the Alps. He also taught himself photography, and realised that he could combine the two interests to make a career that would keep him outdoors. His first assignment, in 1980, was a project on avalanche control for the Smithsonian magazine, for which he spent six weeks running around in snowstorms in the Wasatch mountain range in Utah, watching people throw bombs and fire shells at mountainsides to initiate avalanches. After that it was a shoot for Life magazine on coyotes, and a full-time career in photography followed. In the late 1990s Balog spent six years photographing America's biggest trees, culminating in a book, Tree: A New Vision of American Forests. "I miss those trees terribly," he says. Some of the best months of my life were spent up in those redwood and sequoia forests. It was during this time that he started to think about climate change. He was not exactly a doubter, but he wondered how it could be possible for humans to alter the chemistry of the planet. He read up on the science and discovered the existence of the ice core analysis from Greenland and Antarctica: huge poles of ice drilled from the ice shelf that, with their trapped bubbles of air revealing the carbon dioxide content, provide a comprehensive history of the climate. In the 1780s ice core records showed carbon dioxide levels were about 280 parts per million (there were natural variations before that but none exceeding that figure); by the mid-1970s they had reached 360 ppm. Now we are at 392 ppm. In the past decade the levels have risen by as much as they did in the previous 10,000 years. Icebergs calved from the Ilulissat fjord in Greenland, the most productive iceberg region in the northern hemisphere, float out to sea. Photo: James Balog Balog knew there was a photographic story to be done on climate change. But I couldn't think of what to do with ice that would be interesting. A photo of a glacier shot at dawn or sunset with rosy light conforms to all the basic notions of pretty pictures, but there's nothing in them that says anything about the change in the atmosphere, nothing that radically illuminates the transitory nature of the ice in response to the climate. Until, that is, he got the call from the New Yorker, and he studied the glacier in Iceland. All of a sudden I was at the boundary of humans and nature again - I was at the place where the glacier was coming to an end. It was sculptural and really evocative; I could see shapes that suggested death, atrophy and decay, shapes evoking mortality and transience - and I knew I could make pictures that are interesting and provocative. That is where the idea for the Extreme Ice Survey began. Balog discussed it with Dennis Demick, his editor at the National Geographic, and secured funding for the project. He is not the only one paying attention: in Iceland there is a network of families who have been keeping records of glacier measurements since the 1920s, in big notebooks. With backing from John Francis, the vice-president for research, conservation and exploration at the National Geographic Society, Balog and his team planned to set up 25 time-lapse cameras at key locations. The problem was that they would be putting very delicate technology into the harshest weather conditions on the planet. They had little experience, and the time-lapse cameras were not available off the shelf as Balog had thought, but had to be constructed. The conditions were dire, the terrain dangerous, and they had to find a way to fasten the cameras to rock. But on March 28 2007 they set up their first camera, focused on the Solheim Glacier in Iceland, and the first picture was shot at 1.10pm. A couple of months later they returned to check the cameras. There were some unpredictable problems - cameras buried under 20ft of snow, cables chewed through by Arctic foxes, lenses sandblasted by weather. But worse was that malfunctioning circuit boards within the cameras meant that several of them - at least 10 - had not worked. They had simply stopped shooting. There is a scene where Balog is leaning against a camera, sobbing and cursing at the frustration and wasted effort. But the team persevered. There are terrifying sequences of Balog climbing down the icy face of a moulin in Greenland (one of the tunnels of meltwater that are sucked down below the ice sheet with terrific force) to get his shots. Throughout all this, he had constant knee trouble. He had already damaged his knees through mountain climbing and hanging from trees, but halfway through the project it became apparent that a third knee operation was necessary, and Balog had to return to America. His assistants carried on. For nearly three weeks they camped out on the ice at Ilulissat in Greenland, the most productive glacier for icebergs in the northern hemisphere, overlooking a vast peninsula of ice that was about to calve. Balog, recovering from surgery back home, was getting an update via satellite phone from his team, Adam LeWinter and Svavar Jonatansson, when there was slight movement and an ominous groaning sound, followed by spectacular activity. For 75 minutes they stood and watched as the thick and creamy-looking walls of cascading ice - 400ft tall in places - imploded and crashed into the sea. The resulting footage - the "largest-ever witnessed calving event" - is mesmerising. James Balog (left) and the documentary director Jeff Orlowski at Survey Canyon, Greenland Fortunately, Jeff Orlowski had been there to capture it. From the start, Balog had known that he would need video footage for fund-raising trailers. Orlowski had been introduced to him by a mutual friend, who said, "Hey, if you need an unpaid videographer, he's your boy. He isn't a seasoned professional, but he's really smart, really energetic and he's a total tech-head. So Orlowski joined the trip. By 2008 Balog was starting to run out of money. I thought, I can't spend any more on video. I don't know when this cash drainage is ever going to stop. But Orlowski pleaded his case. "He said, "I think there's a feature film here, and if you give me the rights to the footage that you've shot and let me shoot some more and raise the money, I'll make the film." " He had never made a film longer than 10 minutes before, and had no resources. But he cut a trailer over the weekend and Balog was hugely impressed. "So I said to him, "I don't know how you're going to pull this off, but it's all yours." " Orlowski brought on board some experienced producers - Jerry Aronson, a filmmaker and professor at the University of Colorado, and Paula Dupré Presman, who produced the Academy Award-winning documentary The Cove - and managed to raise the money. There was no ceiling to his ambitions - he even persuaded George Lucas's Skywalker ranch in California to let him mix the sound there. "He got them to give him the deal of a lifetime," Balog says. There were some hiccups - an earlier draft of the film was initially rejected by Sundance - but a year ago they got the call. They said, ever since An Inconvenient Truth, which was basically an illustrated slide show, we've been waiting for a real film about climate change, and you guys did it. You're in. The film, which opens here next week, has had high acclaim but also been the target of climate change sceptics. "I was anxious about that all summer," Balog says, "knowing that there's a bullseye on my back, but guys, I was in the field. I had 25 of my own cameras looking at this stuff. You can make up whatever fiction you want to around that, but this is the story as I see it, and these are the facts of the case. Pancake ice formations at Ilulissat in Greenland, 2008. That the climate is changing because of global warming is now irrefutable in legitimate scientific circles. You cannot argue with photographic evidence that a glacier in Greenland which had receded eight miles in 100 years has now shrunk a further nine miles in the past 10 years. It is indisputable that as the CO2 content in the air rises, so does the global temperature, and that CO2 is a gas that takes a century to disperse. Natural variations cannot explain the changes in atmospheric conditions: last month was the 333rd consecutive month that global temperatures were above the 20th-century average. Even a small variation in temperature (Greenland has seen an average 4.5-degree Fahrenheit rise since 1990) has had vast and unpredictable consequences on weather systems, with hurricanes, droughts and floods. China, parts of Africa and much of India and Australia have all had their worst floods in decades. "We are now in the midst of a gigantic unplanned, uncontrolled experiment involving the entire planet," Balog writes in the introduction to his book Ice: Portraits of Vanishing Glaciers. Balog is not finished yet. "The ice goes on for ever," he says - or perhaps not. We still have 34 cameras at 16 locations; we had as many as 48 cameras at one time. The project was intended to last three years, but I don't think we can stop now. We have this profound historical document, and the longer we keep the record going the more potent it is. The truth is that despite years of warning, the world has barely begun to take action. There is still no global treaty stipulating cuts in greenhouse gas emissions, and there is no time left to argue any more. Balog says he is doing this for his daughters. I am convinced that in the future people will be aghast at how we could have been so indifferent to this issue, so unwilling to respond to the information. I want to be able to say that I and my team were paying attention. "Chasing Ice" is released in UK cinemas on December 14 (chasingice.co.uk), by Dogwoof and Co-Operative