Taking over 400 years for the first water passage, which cannot be considered sea passage as the ship sailed along the shore at times, another 50 years for the first single season passage by special ice breaking ships, and finally the first solo transit of a special ice capable cargo ship would not appear to support the concept of the passage being open from time to time or that the latest passage was within normal variation according to the scientists who study such things.
http://www.britannica.com/EBchecked/top ... st-PassageSince the end of the 15th century, Western explorers have attempted to establish a commercial sea route north and west around the American land barrier encountered by Christopher Columbus. Such an accomplishment would realize an objective that has eluded man since King Henry VII of England sent John Cabot in search of a northwest route to the Orient in 1497.
http://www.livescience.com/48105-cargo- ... ssage.htmlAnother Arctic milestone was reached this week when a cargo ship fortified against ice completed a solo trip through the hazardous Northwest Passage.
The MV Nunavik, owned by shipping firm Fednav and built in Japan, left Canada's Deception Bay on Sept. 19 and rounded Alaska's Point Barrow on Tuesday (Sept. 30). The Nunavik is the first cargo ship to sail through theNorthwest Passage without an escort from icebreakers, Fednav said.
http://www.livescience.com/1884-arctic- ... ssage.htmlThe legendary passage was first navigated with great difficulty and using a relatively small ship by explorer Roald Amundsen in 1903 to 1906. Predictions for the opening of the Northwest Passage have ranged from 2012 to 2080 at their most conservative.
Fully navigable, the Northwest Passage will make the trip 4,000 miles shorter for ships traveling between Europe and Asia, allowing them to avoid the Panama Canal. The Passage was partially open for a time in 1998, but sailing a ship through at time would have been tricky, Serreze said.
"I wouldn't have wanted to try it" in 1998, Serreze told LiveScience. "Through the years, it's become increasingly open, but still really had not remained open in any kind of viable way. 2007 is really the first year."