An 11-million ton iceberg, perched off the coast of a tiny Greenland village, is striking fear in the hearts of residents. Residents of Innaarsuit worry that a chunk of it could break off and unleash a tsunami upon the town. What happens to the gigantic mountain of ice, which a Danish meteorologist said is 650 feet wide—nearly the length of two football fields—and rises almost 300 feet into the air, depends largely on the weather. A strong wind could push the iceberg into the nearby Baffin Bay, averting a crisis. Alternatively, a large amount of warm precipitation could further destabilize...