Ice loss 'opens Northwest Passage'
(CNN) -- Warming in the Arctic has reduced sea ice to its lowest recorded level, opening up the Northwest Passage, a long-sought shortcut between Europe and Asia, according to new satellite images.
The aerial images released by the European Space Agency shows ice at its lowest level since measurements began 30 years ago -- an "extreme" drop, experts say.
"We have seen the ice-covered area drop to just around 3 million square kilometers, which is about 1 million less than the previous minima of 2005 and 2006," Leif Toudal Pedersen from the Danish National Space Center said on ESA's Web site.
"There has been a reduction of the ice cover over the last 10 years of about 100,000 square kilometers per year on average, so a drop of 1 million in just one year is extreme."
Ice cover in the Arctic Ocean has long been held as an early warning of a changing climate.
Scores of peer-reviewed scientific studies have already documented a steady, worldwide decline in ice cover, from the sea-bound ice covering the North Pole to the vast, land-based ice sheets that cover the Antarctic continent.
Glaciers, from Greenland to the Alps to Mount Kilimanjaro near the equator, also have been vanishing.
The loss of land-based ice is predicted to lead to a future rise in sea levels.
Most estimates predict a rise ranging from a few inches to a meter or more. A substantial rise in sea level could imperil low-lying areas from Bangladesh to Miami, Florida, to Lower Manhattan, and could magnify the damage from landfalling hurricanes and cyclones.
"The strong reduction in just one year certainly raises flags that the ice (in summer) may disappear much sooner than expected and that we urgently need to understand better the processes involved," Pedersen said.
A permanent navigable route through the Northwest passage has been the goal of explorers for centuries, offering a swift maritime trade route between the Pacific and Atlantic Oceans.
The route was first navigated by Roald Amundsen early last century, sea ice has generally rendered it too dangerous.
The opening up of the passage could cause international friction over the sea routes with U.S. and European Union disputing Canada's claim to the waters.