Arctic Sinkholes

 
Vast explosions shake a remote corner of the Siberian tundra, leaving behind massive craters. In Alaska, a huge lake erupts with bubbles of inflammable gas. Now an international team of scientists reveal a ticking time bomb, as permafrost melts releasing vast amounts of methane, a potent greenhouse gas, into our atmosphere.

What does this mean for the indigenous peoples who live in the Arctic Circle - and for all life on our planet?

With stunning footage gathered across Alaska, Russia, Norway and the Greenland Sea, this is the story of a race against time at the very frontiers of science to understand the hidden dangers to our climate - before it's too late.