The Greenlandic tundra disintegrated beneath my feet. As I ran north from Ilulissat on a sunny June morning, my shoes kicked up a cloud of dust behind me, the lifeless detritus of 1.7 billion year-old rocks. Where springy green moss and little pink flowers once grew now lay gray grit.
To my right, jagged boulders lined a makeshift road leading to a quarry at the to...
