Garth Lenz is one of the world’s most famous conservation photographers (with a perfect name for it), and here he is with a TED Talk, using his stunning photography to illustrate exactly what happens to an ecosystem when we mine its tar sands to extract oil. It’s pretty shocking to see the terrible reality behind the Keystone XL debate.

Lenz gets choked up at a couple of points in his presentation, and it isn’t hard to see why.