ASPEN — Probably no bit of information presented at the Aspen Environment Forum was as sobering as the screening of the film “Extreme Ice” at the Wheeler Opera House Thursday night.

The documentary used time-lapse photography to show how the biggest glaciers in the world are disappearing because of global warming. “Seeing is believing” is the motto for the film and for the Extreme Ice Survey, a research project sponsored by National Geographic.

Photojournalist James Balog and the Extreme Ice Survey team installed 27 time-lapse cameras at 15 sites in Greenland, Iceland, Alaska and other places to document the dramatic retreat of the ice floes.

The general information wasn’t new for anyone paying attention to climate change issues. It’s well known, for example, that Glacier National Park in Montana will soon be without glaciers.

But “Extreme Ice” provides stunning visual evidence that goes well beyond comparisons of still photographs from different years. The time-lapse photography shows the big glaciers melting away like a plastic bread wrapper on fire.

Many of Balog’s photographs are artistically stunning as well. You can feel Balog’s stated pain as he photographs broken chunks of glaciers getting carried out to sea by the tide. It’s like he is lamenting the death of an endangered animal. In another scene, he shows how the melting ice has uncovered a layer where dirt and debris collected. He exclaims that the glacier seems lifeless and you know what he means from the image.

But he also displayed the beauty of the glaciers. In one harrowing scene, Balog rappels into a chasm opened by a torrent of water gushing from a melting glacier. The ice is layered just like sandstone in the canyon country of Utah. He captures the cool blue of the ice in other pictures.

Video also shows massive chunks of ice collapsing into water and, most remarkably, popping up from the water like a cork.

See this strangely beautiful piece for yourself. Go to http://www.extremeicesurvey.org/.

scondon@aspentimes.com