Arctic icebergs to remain a threat to shipping for some time, experts warn
2 Novembre 2007
As the extent of the Arctic sea ice continues to diminish, freeing up sea routes such as the Northwest Passage, increasing numbers of ships are heading north to explore these polar waters.
However, the International Ice Charting Working Group has warned that sea ice and icebergs will continue to pose a threat to shipping in polar waters for a number of years.
‘The Arctic is already experiencing an increase in shipping, primarily for oil and gas development and tourism, and we can expect to see further increases as diminishing ice extent makes Arctic
marine transportation more viable,’ the ice experts write in a statement issued during a conference on the polar regions taking place in Italy. ‘The International Ice Charting Working Group
(IICWG) cautions that sea ice and icebergs will continue to present significant hazards to navigation for the foreseeable future.’
This year saw the summer sea ice reach its lowest extent yet, of just 4.1 million square kilometres. The previous record, set in 2005, was 5.3 million square kilometres. The Northwest Passage
in the Canadian Arctic was virtually unhindered by sea ice from mid August until well into October, while large stretches of the Northern Sea Route, which runs across the top of Russia, were
also clear for several weeks. The remaining sea ice was also much thinner than a few years ago.
The scientists also note that the Arctic ‘will still have a winter ice cover that will linger into summer for varying lengths of time depending on a range of conditions’.
The sharp reduction in sea ice in 2007 came as a surprise to scientists, who had not expected to see such low levels of sea ice until the middle of the century. ‘The overall extent was similar
to what some of the models envisioned, but decades in advance of when they expected that would occur,’ commented Douglas Bancroft, Director of the Canadian Ice Service. ‘In fact, the summer of
2007 looked very similar to some climate model forecasts for 2030 to 2050.’
Much of the data on the extent of the sea ice comes from satellites, including the European Space Agency’s Envisat satellite, which includes the Advanced Synthetic Aperture Radar (ASAR).
‘We have been very lucky to have had the capability to monitor the polar regions with satellites since the 1970s because it has allowed us to fully capture the trend,’ said Dr Pablo
Clemente-Colón, Chief Scientist at the US National Ice Center. ‘Furthermore, because of satellite monitoring we will be able – with a high degree of precision – to indicate if the trend
is reversing, continuing or worsening.’
The working group’s ability to monitor the situation at the poles will be given a boost with the launch, in 2009, of the European Space Agency’s CryoSat-2 satellite. CryoSat-2 will make
observations that will provide conclusive evidence on the rates at which ice cover is diminishing.
Meanwhile, the IICWG pledged to work with national and international authorities to help ensure that Arctic navigation ‘develops with the utmost regard for the safety of people, property and