In August, the luxury cruise ship Crystal Serenity will depart Seward, Alaska, on an Arctic adventure. The 32-day voyage will take passengers and crew up the Bering Strait, through the Northwest Passage and along the coast of Greenland before the ship docks in New York City in mid-September.

While the Crystal Serenity will not be the first tourist vessel to transit the passage, it will be the largest. More than 1,000 passengers and 600 crew will be on board for the voyage.

“There is a lot of emphasis on this particular transit because it is the first high-capacity vessel that will make the transit,” said Lt. Commander Jason Boyle of the U.S. Coast Guard. “But any trip across the Arctic has logistical challenges and weather challenges.”

Officials from both the U.S. and Canadian coast guards are meeting in Fairbanks, Alaska, this week to test their ability to conduct a mass rescue from a luxury cruise ship in the Beaufort Sea, near the shared Canada-U.S. border. The scenario, which will play out as a tabletop exercise, will be carried out with the ship operator Crystal Cruises, Transport Canada, the State of Alaska and the North Slope Borough.

The exercise will give rescue officials and the cruise operator a chance to run through the emergency response to figure out how they would evacuate the passengers and crew and get them to shore, where they would go and how they would eventually get them home.

The scenario has been designed so that it will force the operator to evacuate the ship. “That is the last thing you want to do in any emergency,” Boyle said.

The Northwest Passage is not a single route, but a complex warren of channels, bays and straits. It is frequently described as having a northern passage and a southern passage.

The northern route passes through the Parry Channel, above Victoria Island and Banks Island. It is relatively deep, but rarely used, in part because the waters are often frozen with multiyear ice.

The Crystal Serenity will follow the southern route, tracing the path navigated by Roald Amundsen in 1903–06. From east to west, it stays close to the mainland, passing south of Prince of Wales Island and Victoria Island and entering the Beaufort Sea south of Banks Island. It is well protected from drifting ice, but it is shallow.

About 90 percent of transits through the Northwest Passage use the southern route, according to a report published by the government of Nunavut.

Ice conditions have historically ruled out commercial shipping through the Northwest Passage, but as the sea ice recedes and thins across the Arctic, it may well lead to easier ship access.

Images from the Suomi-NPP and Landsat 8 satellites showed the passage was open for several weeks during the summer of 2015, whereas the northern route remained choked with ice.

But some researchers point out that the changing sea-ice conditions could lead to an increase in navigational hazards. “There are a number of studies that look at how climate change and melting ice will actually increase the likelihood of encountering very thick and hard multiyear ice in the Northwest Passage,” Scott Stephenson told Arctic Deeply in February.

Between 2005 and 2012, only two to four cruise ships or tourist icebreakers have made complete transits of the route each year, but these have also been small vessels – nothing as large as the Crystal Serenity. Of the 30 boats that transited the passage in 2012, 22 were pleasure boats, according to data from NORDREG, the Canadian Coast Guard’s Arctic vessel traffic reporting system.

In 2013, 30 vessels transited the Northwest Passage, including, for the first time, a large bulk carrier called the Nordic Orion. The ship, which has roughly the same length and beam as the Crystal Serenity, had been loaded up with coal in British Columbia and was destined for Finland.

The following year, only 17 vessels managed to make the trip due to the cold summer and ice conditions.

Despite the uptick in transits in recent years, the voyage remains tricky. Shallow areas, shifting sand and gravel bars, fog and dangerous weather add to the risk. During the summer months, ice from the North Pole drifts southward and can clog the straits of the Northwest Passage.

In 2010, the Clipper Adventurer ran aground on a shoal in the Southern Coronation Gulf, which lies between Victoria Island and mainland Nunavut. Unable to dislodge the ship, the crew evacuated the 128 passengers and transferred them to the Amundsen, a Canadian Coast Guard icebreaker that arrived at the scene 40 hours after the incident.

An icebreaker equipped with a helicopter will accompany the Crystal Serenity on the voyage for added security. The cruise line has also added additional equipment to the ship, including a high-resolution radar that will allow it to scan the waters ahead to look for obstructions or uncharted rocks. Both vessels will burn low-sulfur fuel, which will reduce black carbon emissions, but will still pose an environmental problem in the event of an oil spill.

The U.S. Coast Guard will carry out its usual operations in the Arctic during the cruise.

Once the ship emerges from the Northwest Passage at the top of Baffin Island, it will cross the Davis Strait and head for Ilulissat, Greenland.

In February, a Canadian fishing vessel struck ice in the Davis Strait, off Baffin Island, and began to take on water. The Danish Navy and the Canadian Coast Guard came to its rescue, providing it with emergency pumps and escorting it to Nuuk, Greenland through rough seas.

In October, all eight Arctic nations signed an agreement to help each other out in an emergency response. It adds to the 2011 treaty on search and rescue operations that was negotiated by the Arctic Council.

In an interview with CBC Radio, Michael Byers, a political scientist at the University of British Columbia, said he was worried about the precedent the Crystal Serenity might set. Other cruise lines may not take the same precautions as Crystal, he warned. “It could be a very large market and at some point an accident will occur,” he said.

Top image: The Crystal Serenity will have more than 1,000 passengers and 600 crew on board when it transits the Northwest Passage this summer. (Wikimedia Commons/Alexander Baxevanis)