During Antarctica's austral summer, the depth of the annual ice pack must be measured at least twice weekly to ensure the safety of all traffic. When the sea ice melts to less than three feet thick, it will be closed for the season.
The typical Antarctic scene, the only colors being white and blue, and the 'BIG RED' of our issued cold-weather jackets.
Sea ice fractures start off small, then heal themselves as the Ross Sea fills in the crack and refreezes. The fracture will open again, then freeze again, sometimes so often that the size of the fracture can eventually become over 30 feet wide.
These large fractures are measured in depth throughout the season. First, a trough is shoveled out perpendicular to the fracture.