The ice edge changes daily-even hourly. This is the entrance to Arthur Harbor as seen from the station. The intake pump house (for desalination and the aquarium) is at the left. The wind packs ice into Arthur Harbor some days, and takes it away on other. When it’s cold enough outside, sea ice forms in situ. I watched three Antarctic turns flying a dipping right along the ice edge today. They kept this up for over 3 hours in a stiff 10 degrees F wind, so I’m guessing they were finding a good meal in the accumulating ice.