Al Sutherland, ocean projects manager in NSF's Office of Polar Programs, said the ice extends almost three times farther out from the station than is usual.
Normally, the ice edge -- the place where the ice in McMurdo Sound meets open water -- would be found about 15 miles from McMurdo Station. Currently, Sutherland said, the ice edge is nearly 40 miles out. He added that very dense "pack ice" stretches roughly 200 miles from the station to iceberg C-19, which broke away from the Ross Ice Shelf in May.
The U.S. Coast Guard vessel Healy, an icebreaker with design features for supporting Polar science, particularly in the Arctic, left its home port of Seattle on Jan. 9th, to sail south for roughly 27 days to join the Coast Guard icebreaker Polar Sea, which already is working in McMurdo Sound.
Healy recently conducted a very productive science season in the Arctic, notably in support of the NSF-supported Western Shelf-Basins Interactions (SBI) project, which is looking for early indicators of climate change in the Arctic Ocean. Researchers on a previous Healy cruise found evidence that the Arctic's Gakkel Ridge, the world's slowest spreading mid-ocean ridge, may have substantial volcanic activity.
NSF concurred with a Coast Guard recommendation to send Healy to assist in icebreaking operations. Coast Guard officials have assured NSF that Healy's Antarctic deployment will not affect planned Arctic research. It is possible that Healy could be recalled if conditions do not warrant its prolonged presence in Antarctica.
A freighter and a fuel tanker annually provide a lifeline that allows the U.S Antarctic Program to conduct science on the southernmost continent.