By Kathryn Westcott
This week, Europe's space agency (Esa) reported that the shrinking of Arctic ice had opened the fabled Northwest Passage, clearing a long-sought, but until recently impassable, route between Europe and Asia.
The search for a route from the Atlantic around the top of North America and into the Pacific consumed explorers for centuries. Now a growing band of sailing adventurers are traversing the waterway in record times.
This summer, the agency says the passage has been seen to be fully navigable for the first time since satellite records began. Indeed, 2007 was an active year for sailors in the region, according to Peter Semotiuk, who helps mariners navigate their small craft along the route.
Every evening in the summer months, the ham-radio operator provides detailed weather and ice reports, tracks each boat's position and passes on news from other sailors to each of the boats out in the wilderness.
Mr Semotiuk has operated his single-band sailor's radio network for the past two decades from his hometown of Cambridge Bay, Nunavut, Canada, a port in the middle of the Northwest Passage.
In 1969 the SS Manhattan became the first commercial ship to travel the Northwest Passage
One recent summer, he helped co-ordinate a rescue mission for four boats that had become stuck in the ice.
In contrast to this year's lack of ice, he described 2005 as a "tough" year. Eight boats tried to get through, but only two succeeded and only with help from ice-breakers.
Mr Semotiuk, who has now signed off for the winter, told the BBC News website that a third boat this season - a lightweight catamaran crewed by a French and Belgian team - had just successfully navigated the full length of the 5,150km (3,200-mile) waterway.
This is the first time the journey has been completed entirely by sail, says Mr Semotiuk. Not so long ago, he says this journey would have been impossible because of the ice.
There has been a marked shrinkage in ice cover in the region in recent years, but this year it was extreme, according to Europe's space agency.
Mr Semotiuk, who completed the journey himself in 1988, said: "This summer the passage was largely wide open.
"It's a very different picture to say 20 years ago, when I travelled the length of the passage.
"The owner of the boat I was travelling on had been trying to get through for five years. On the sixth year, we were successful, although we had to wait for two weeks in the central Arctic for the ice to break."
Then, Mr Semotiuk would have been making a journey that only the most intrepid traveller would have dared to undertake.
In 1905, Norwegian explorer Roald Amundsen became the first person to successfully navigate the Northwest Passage, in a wooden sailboat.
Other ships that had tried earlier than this had been forced to abandon the quest, had disappeared or had been "crushed like a nut on the shoals and buried in the ice", as one 20th-century Canadian captain put it.
But since then, about 110 boats had successfully completed the trip, said Mr Semotiuk. Thirty of those were recreational boats, most of which completed the journey in the past decade.
And, where once the journey could have taken years, with sailors being forced to overwinter in ports along the passage due to the ice conditions, this year it was possible to complete the journey in record time.
Roger Swanson, a 76-year-old pig farmer turned yachtsman from Minnesota, completed the journey last week after just 45 days.
Speaking to journalists, he described the journey as smooth sailing.
"There was hardly any ice," Mr Swanson told the Wall Street Journal.
This was all very different to his previous attempt in 2005, when he was forced to turn around, vowing never to return.
A father-and-son British team also completed the journey this year.
"One of the British sailors, James Allison, said he felt a bit of a fraud after completing the trip because there wasn't any ice," said Mr Semotiuk.
"He's correct to the point that there really wasn't any challenge, so to speak, other than the cold."
Mr Semotiuk expects a greater number of sailors to turn up next season.
"But that's not to say the risks are not there," he said. "We could see more icebergs in the eastern Arctic as more glaciers melt off Greenland and off the Canadian east coast."
The Northwest Passage was the goal of Arctic explorers from the 16th to the 19th centuries. Efforts to discover a trade route through or around North America began in the 1490s with the voyages of John Cabot.
Along the route, there are salutary reminders of those who lost their lives searching for what has been described as the holy grail of mariners.
A number of graves belonging to crew from an ill-fated expedition headed by Sir John Franklin, who sailed from England in the spring of 1845, are a reminder of the region's inhospitable past.
Franklin's two ships, the Erebus and Terror, and 129 men disappeared. The fate of the crewmen is a mystery that remains unsolved.
The commercial implications for the waterway could now be great.
"But, for all this", says Mr Semotiuk wistfully, "I hope the fabled Northwest Passage doesn't become spoilt."