Ever wonder why some icebergs and glaciers are so blue? Here’s the simplest answer: Ultra cold ice, which has had all the air bubbles squeezed out, absorbs all but the short-wave-length blue light of the visible light spectrum. As the ice is exposed to warmer air or warmer water, the crystal structure breaks down and begins reflecting all the light, which then makes the ice appear white. That’s why the deepest blue coloration is often seen in crevasses or in places where chunks of ice have recently calved.

–Post and photos of ice in Patagonia and Antarctica by Bill Abbott, Wilderness Travel founder and president, Antarctica, South Georgia, and the Falkland Islands