Travelling to a Himalayan glacier
24 September 2013 Last updated at 00:36 BST
Scientists have discovered that smoke from cooking stoves and dirty engines is causing glaciers to melt faster.
The glaciers are already under pressure from climate change. The smoke also deposits black soot on to the glaciers, which makes them absorb more heat.
Roger Harrabin and cameraman Neil Paton travelled to the Batal Glacier in India to film a piece as part of the BBC's Intergovernmental Panel on Climate Change coverage.
Roger talks about his travel experience and what it was like to see a glacier up close.