Child on Swing, Siorapaluk, Greenland, 2006Photograph by David McLainA flawless blue Arctic sky frames a child swinging in Siorapaluk, Greenland, the northernmost permanent settlement in the world. During the past few decades, temperatures have risen in Greenland by more than 2 degrees Fahrenheit (1.1 degrees Celsius)—twice the global average—and the island's massive ice sheet is melting faster than at any time during the past 50 years, pushing the Arctic ecosystem into collapse.