The Great Melt: Is It Normal, or the Result of Global Warming?

Scientists are having difficulty pinpointing the causes of glacial and sea-ice decline

By COLIN WOODARD

Jokulsarlon, Iceland

From the gravelly, newborn shores of this frigid lagoon, Iceland's Vatnajokull icecap is breathtaking. The vast dome of snow and ice descends from angry clouds to smother jagged, 3,000-foot-tall mountains. It spills out from the peaks...