In rare and stunning footage, filmmakers behind a newly released documentary captured the largest-ever iceberg calving yet seen off the Greenland ice shelf's Ilulissat glacier.

The footage is just one part of a new documentary called "Chasing Ice," by filmmaker James Balog, which released in the U.K. and across the U.S. on Friday, and an excerpt was published by The Guardian on Wednesday. The film documents in excruciating detail how the Greenland ice is melting due to climate change.

"Traveling with a team of young adventurers across the brutal Arctic, Balog risks his career and his well-being in pursuit of the biggest story facing humanity," the film's website explains. "As the debate polarizes America, and the intensity of natural disasters ramps up globally, Chasing Ice depicts a heroic photojournalist on a mission to deliver fragile hope to our carbon-powered planet."

Satellite photography taken earlier this year showed that arctic sea ice shrank this summer to less than half what it was about four decades ago, reaching a record low in August 2012. The European Space Agency said earlier this year that the rate of loss is about 50 percent faster than previously forecast.

This video is from The Guardian, published Wednesday, December 12, 2012.

This is the official trailer for "Chasing Ice," published to YouTube on September 4, 2012.