There are plenty of ways for an iceberg to make an entrance. This one, for instance, practically did a backflip. A video from Iceland captures a massive piece of ice suddenly surging upward from beneath the surface, rolling onto its side and throwing an enormous section of blue-white ice into the air. As the berg completes its slow-motion somersault, water pours off its newly exposed face and a series of small tsunami-like waves radiates outward. It looks bizarre, but there’s some serious physics behind it. See the video linked here and below. View this post on Instagram One possible mechanism is submarine calving, when ice breaks away from the submerged portion of a glacier and buoyancy sends it rocketing toward the surface. The National Park Service describes these “basal bergs” as pieces of underwater glacier ice that “rise suddenly and unexpectedly,” sometimes emerging “explosively, without warning at the water surface.” The U.S.…