Introduction to today's journey
THE ICE around Antarctica takes on two forms. The large jagged icebergs looking like mountains floating in the water are pieces of fresh water ice broken from the glaciers and ice shelf of the mainland. The largest of these icebergs are enormous slabs with a flat surface up to thirty metres above the surface. These too are fresh water icebergs. The smaller slabs sitting up to a metre above the surface are the salt water iceberg remnants from when the sea froze over last winter, where the pack ice extends hundreds of kilometres offshore. Most of this sea ice melts, but some icebergs remain in the freezing cold water. These are more readily able to melt than the fresh water icebergs as the freezing point of sea water is a couple of degrees below the freezing point of fresh water. Although some of the fresh water icebergs look enormous, only ten percent of them float above the surface. All the ice seen above the surface has ten times the volume underneath. A slab iceberg with its surface thirty metres above the surface has solid ice three hundred metres deep in the water. These are truly massive.
Today's journey returns around the north of Adelaide Island and across Crystal Sound to Fish Islands just off the mainland. Here we explore the massive ice field by Zodiac boat before heading back out to sea to continue northward.
Today's Journey
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