Their Physical Characteristics
Icebergs are beautiful fragmented shapes of freshwater ice usually found floating in the ocean. They originate from a mass of ice that has broken off a glacier (called a calcen) and has fallen into a nearby body of water. They are therefore of freshwater origin from precipitation (snow) that formed the glacier. In contrast, sea ice is frozen sea water of salty content. Icebergs come in different colors -- white, cyan, light blue, dark blue and green. White is the standard color and is a result of many tiny air bubbles in the superficial snow and ice reflecting and scattering all colors of light -- i.e appears white. In contrast, blue icebergs are made up of ice deep within the glacier which has compressed most of the air out of the ice and has very few air bubbles, so it shows its natural blue color. The ice now tends to absorb light in the red region of the spectrum and the light that you see from this kind of an iceberg will appear blue. Although icebergs are from newly broken off glaciers (that may be thousand years old), they're often mixed with flecks of black and brown from ground up rock. Their unusual shapes are caused by weathering effects from wind, waves and melting. Some of the icebergs that have broken off of the Antarctic ice shelves have been monsters - one was the size of the state of Conneticut! In the Arctic, icebergs are smaller. Car or house-sized icebergs are sometimes called "growlers." The smallest icebergs are known as "bergy bits".
Iceberg Photos from Antarctica
Iceberg Photos from Chile
(Laguna San Rafael)
mouse click on any of the thumb nail images below for an enlargement