It's 5 a.m., and we are at the eastern entrance to Bellot Strait – the heart of the Northwest Passage. We're waiting for the right moment to make the run to the other side. These waters are not for the faint-hearted. The strait is 20 nautical miles long and one mile wide, and the current is brutal. If it is running too fast behind you, you can't control the ship. If it's running against you, getting through will take forever.
"This moment has been in my head for a week," Stéphan Guy says. He is the captain of our ship, a sturdy little icebreaker called the Polar Prince. The tidal charts aren't very good. He has to see and feel the tide and currents for himself.
There are several ways to take the Northwest Passage to the Beaufort Sea. But even as the polar ice recedes, none of them are easy. Not all the modern navigation tools in the world can replace the need for a pilot's skill and judgment.
As we wait, flocks of northern fulmars skim across the water. The first mate chats about the early explorers who were at the mercy of the ice. Many of their ships were beset in these waters – trapped in ice through the winter until the next year offered a way out. Many of the men never made it home.
At 5:40 a.m., the captain gives the order. We're going. To our left is the northernmost tip of mainland Canada. To our right is the endless string of islands of the Arctic.
All week he's been pondering another question. "Do we need to call an icebreaker bigger than us? Do we mobilize one just in case?"
The satellite data show that most of the water to the west is covered with heavy, impenetrable ice. There's a narrow band of more open water along the coastline, and that is where we're heading. A sudden shift of wind and weather could quickly close it off. Can we make it?
Capt. Guy has decided that we can. He's confident enough that he has decided to cancel the larger icebreaker. Besides, the Coast Guard doesn't have many assets up here, and you don't want to tie them up unless you really have to.
"Today is the last day of our window," he says. "But it's not 100 per cent. It's never 100 per cent."
Let's hope he has judged well. The nearest Coast Guard icebreaker, the Terry Fox, is four days away.
As ice conditions improve, the Northwest Passage is far more navigable than it used to be. But it's still a calculated risk. The Crystal Serenity, a 1,000-passenger luxury cruise ship, made it safely through these waters last year. The first big freighter came through in 2014, and more cargo traffic is on the way. There's a lot of starry-eyed talk about cutting a week or two off shipping times between Europe and Asia.
But the challenges are still immense. The Northwest Passage (which describes the whole route from the Davis Strait to the Bering Sea) is ice-locked for most of the year and has no deep-sea ports or major stopping-off points. Only 4 per cent of these waters are fully charted, and the shifting weather can change the ice formations overnight. Travel delays are not uncommon, and the hazards of these waters bump up the insurance premiums.
Capt. Guy isn't so worried about the effects of more traffic on the environment as he is about vessels that get stranded. What if a big passenger ship runs aground (as happened in the passage a few years ago)? How, and how fast, could people be evacuated? Our Coast Guard fleet is minuscule. "We're not equipped to deal with the risk," he says.
Besides, no one really knows who's in charge up here. The land belongs to Canada. Canada claims the waters are "internal," but the United States claims that the Northwest Passage is an "international strait," and that ships from all countries have the right to "transit passage."
Today, it's practically a traffic jam. We pass a Russian passenger ship and a private sailboat heading east. The sailors are an Austrian family with two kids and a dog, heading back to Europe across the North Atlantic.
By 8 o'clock or so, we have reached the western end of the strait and turn south into open water. There's much more ice here. The water has a denser, viscous look. Patches of new ice, like thin glass, have begun to form on the water's surface. The water is calm. The sailing ahead should be relatively smooth.
Every so often, a seal pops its head above the water. Delicious breakfast smells are wafting up to the ship's bridge from the galley. The captain goes down to grab some breakfast. It's a beautiful day in the Arctic.
Margaret Wente is spending 12 days with the Canada C3 Expedition, which is circumnavigating the Canadian Arctic to mark Canada's 150th birthday. She will be with the C3 ship from Pond Inlet through the Northwest Passage.