Extreme Arctic Thaws
In June I wrote that sea levels will rise by several metres by the end of the century due to rapidly increasing greenhouse gas concentrations, and here we are just 3 months later with news that the Arctic's sea covering has shrunk so much that the Northwest Passage, the fabled sea route that connects Europe and Asia, has opened up for the first time since records began. US scientists said it suggested the whole of the Arctic could be ice-free by 2030, far sooner than previously predicted.
According to scientists led by Leif Toudal Pedersen of the Danish National Space Centre, Arctic ice this summer dropped to around 3 million square kilometres, a decrease of 1 million square kilometres on last year's coverage. Given that for the past 10 years Arctic ice has been disappearing at an average annual rate of only 100,000 square kilometres, this year's reduction is 'extreme', said Pedersen.
A boat sails by an iceberg in the Jacobshavn Bay, near the town of Ilulissat, Greenland.
Photo: Getty Images
The Greenland ice cap is melting so quickly that it is triggering earthquakes as pieces of ice several cubic kilometres in size break off.
Scientists monitoring events this summer say the acceleration could be catastrophic in terms of sea-level rise and make predictions this February by the Intergovernmental Panel on Climate Change far too low.
The glacier at Ilulissat, which supposedly spawned the iceberg that sank the Titantic, is now flowing three times faster into the sea than it was 10 years ago. Almost all experts say global warming, stoked by human use of fossil fuels, is happening about twice as fast in the Arctic as elsewhere on the planet. Once exposed, dark ground or sea soak up far more heat than ice and snow.
Sea ice has shrunk in the Arctic to its lowest level since satellite measurements began 30 years ago, showing images of the now "fully navigable" route between the Atlantic and the Pacific.
An orange line shows the most direct route the ice-free Northwest Passage beside partially blocked Northeast passage (blue line) in this Envisat ASAR mosaic.
A shipping route through the Northwest Passage in the Canadian Arctic has been touted as a possible cheaper option to the Panama Canal for many shippers. The steady melting of the north polar icesheet has already provoked international tensions over the possibility of gaining access to the vast reserves of oil and gas believed to lie beneath the seabed. Countries such as Russia are hoping for new shipping routes or to find oil and gas. Canada has also been pressing its Arctic sovereignty claim and has announced plans for a deep-water port at Nanisivik near the eastern entrance of the Northwest Passage, which will allow it to refuel its military patrol ships.
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