Santa Claus is getting nervous: Judging from satellite images taken last month, the Arctic’s perennial sea ice pack has encountered gaping openings of territory reaching all the way to the North Pole.

Observing data from Envisat’s Advanced Synthetic Aperture Radar (ASAR) instrument and the AMSR-E instrument aboard the EOS Aqua satellite, scientists have determined that between 5 and 10 percent of the Arctic’s perennial pack, despite surviving annual summer melt, has been fragmented by late summer storms.

As a result, the area between Spitzbergen, the North Pole and Severnaya Zemlya — a geographical range larger than that of the British Isles — is confirmed by AMSR-E to have had much lower ice concentrations than ever before.

"This situation is unlike anything observed in previous record-low ice seasons," said Mark Drinkwater of ESA’s Oceans/Ice Unit. "It is highly imaginable that a ship could have passed from [Northern Siberia]… to reach the North Pole without difficulty."

And that’s not clear sailing, say scientists. For the past couple of years, satellite observations have shown that the extent of the ice is rapidly deteriorating, but observations from August 23 through 25 mark the first time the pack in the region appears thinner and more mobile than ever.

According to NASA, maximum ice in the Arctic winter has fallen by 6 percent each of the last two winters, compared to merely 1.5 percent per decade on average since the earliest satellite monitoring in 1979.

From an area of around 3.09 million square miles in the early 1980s, an historic minimum of less than 2.12 million square miles remained by 2005, believed due to greenhouse warming.

Satellites have now provided 27 years’ data, said Joey Comiso, a research scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., whose findings on greenhouse-gas effects will be published this month in Geophysical Research Letters.