Shrinking glaciers: Mont Blanc from the air, 100 years on

A century after Walter Mittelholzer's famous aerial mission, scientists repeat his journey to shed light on the impact of global heating

In 1919, the Swiss pilot and photographer Walter Mittelholzer flew over Mont Blanc in a biplane photographing the alpine landscape. A century on, scientists have recreated his images to show the impact of global heating on the mountain's glaciers.

Dr Kieran Baxter and Dr Alice Watterson from the University of Dundee used a process called monoplotting to work out the precise locations from which Mittelholzer had taken his photographs. They returned to the spot in a helicopter and lined up their cameras using the alpine peaks as their guide.