The ice occurs in bands that break off the ice edge further to the south and are transported northward. In this image a couple of ice types are visible. The underwater portion of the ice is about 7 times the thickness of the portion visible above the water. Some of the larger floes are flat while others have tall ridges that form when two floes are compressed together under the pressure caused by winds and currents, much like mountain formation. As we traveled further south towards Casey Station the ice cover increased and the patches of open water and thinner ice decreased.
Ice is overturned as the ship moves through it, exposing the underside of the ice.
The brown color and streaks are ice algae that live on the underside of the ice and in the interface between the ice and snow. This time of year, when the sunlight increases, algae bloom in the ice. They absorb visible light, using it for photosynthesis. Excess absorbed energy is transformed to heat, which stimulates the melting of sea ice where the algae accumulate. Antarctic krill graze the algae along the underside of sea ice.