Momentous change doesn't always leave visual cues. A 2008 Obama looks much the same as a 2012 Obama (minus a few gray hairs and Benghazi wrinkles). In some ways, climate change is similar; we can't exactly see villainous clouds of CO2 strangling the sky. But when it comes to glaciers, climate change leaves marks that can be seen from space.
Our friends at GlacierWorks hope to document those scars. Respected mountaineer and GlacierWorks Executive Director David Breashears retraced the steps of past photographers from the Royal Geographical Society to reshoot photos of famous Himalayan glaciers affected by climate change. Thanks to their hard work and internet magic, we can now compare the severity of ice recession by combining the historic and modern images.
On the left is a photo taken by Major E. O. Wheeler in 1921 on the North slope of 26,906-foot Cho Oyu; on the right is a photo taken by Breashears from a similar perspective in 2009. Drag the slider to check out the changes China's Kyetrak Glacier experienced.
Now compare the Main Rongbuk Glacier (near Mt. Everest) in a 1921 photo by George Mallory to Breashears' 2007 image: