Arctic sea ice this year was melting faster than is usual as August ended -- perhaps fast enough to open a deepwater route in Northwest Canada for the first time since 2007, experts said.
Only a small portion of the M'Clure Strait passage through the Canadian Arctic Archipelago was blocked by ice at the end of August, according to the monthly report from the National Snow and Ice Data Center. And if the ice continues to retreat as fast as it has in the last few weeks, the passage, which is a better route for big ships than the shallower Northwest Passage, could open within a week.
"Normally that's the one that's closed entirely in September," NSIDC Director Mark Serreze said. "If you're trying to take a big ship through there, you'd want to use this deepwater passage."
Serreze said the last time he saw the M'Clure Strait open was in 2007.
It may happen again this year because there is less ice than usual, and it has been retreating at a fast and steady rate. During August, the Arctic lost about 29,000 square miles of ice cover a day,? the NSIDC reported. The average for August is about 22,100 square miles per day.
The rapid loss may have been the result of hotter air temperatures above Norway and the North Pole, where they were 3 to 5 degrees above average, according to the report.
When compared to satellite records dating back nearly four decades, overall sea ice coverage, also known as the sea ice extent, reached its fourth-lowest level in August, at 2.16 million square miles. That's about 621,000 million square miles below average, according to the report.
Serreze said the ice coverage reaches its lowest in September. He predicts that this year will be either the fourth- or third-lowest on record. "Most likely the fourth," he said.
Arctic sea ice has been erratic this year.
In February, the iciest month of the year, ice cover was at an all-time low, and the annual melt started weeks earlier than its usual mid-March onset. But the rate of ice loss in summer months went back and forth between slow and fast. Now, at the end of August -- a time when melting usually begins to slow -- it's continuing at a faster rate than normal.
A storm recently battered the Chukchi Sea, flooding Barrow and forcing Shell to halt drilling operations, but Serreze said it "probably didn't have a huge effect" on the ice nearby.
He said NSIDC examined how storms affected sea ice extent in 2012, when it reached the all-time record low, and that "It had some effect, but probably not that big." Overall weather patterns tend to matter more than individual storms, he said.