As part of his documentary film Chasing Ice, National Geographic photographer James Balog travelled around the world using time-lapse cameras to show how the planet’s glaciers are changing in the face of climate change. One day, while filming, the crew witnessed something that has never been seen in living memory – a three-mile section of a glacier collapsed into the sea.

Chasing Ice

The (literally) earth-shattering event took place in Western Greenland on the Jakobshavn Glacier. While filming the glacier, the crew witnessed a large scale ice calving event that, when it was finally over an hour later, saw the glacier retreat a full mile for a width of three miles.

Related: Iceberg Twice the Size of Manhattan Breaks Off Greenland Glacier

The stunning footage will be featured in the final documentary, which has already received the 2014 News and Documentary Emmy® award for Outstanding Nature Programming. The film has been screened in more than 172 countries and on all seven continents. For more information on the film, click here or watch the stunning trailer below.

+ Chasing Ice