TROMSO, Norway — Just days before the German icebreaker Polarstern sets sail on the largest and most ambitious climate-change research expedition the Arctic has ever seen, an air of quiet pandemonium prevails aboard ship.
Crates of scientific equipment — more than a million pounds in all — are stacked on deck and in passageways, scattered seemingly at random among spools of hose, gas cylinders, duffels filled with survival gear and even a spare blade for the ship’s twin propellers.
Scientists scurry about, sorting through supplies and making sure equipment is working and strapped down in the research ship’s permanent laboratories and more than a dozen portable ones in modified shipping containers, above and below deck.
The crew is performing its own last-minute tasks, including lifting four gleaming new snowmobiles aboard with a crane. Dangling high in the air, the machines look like insects against the hulking 400-foot-long ship.
To the untrained eye, it seems impossible that the chaos will end in a matter of hours. But Felix Lauber, the Polarstern’s first officer who is a veteran of many shorter expeditions in the Arctic and Antarctic, is confident.
“We’ll be ready to go” he said.
On Friday evening the ship was indeed ready to go, and a crowd of several hundred gathered on the dock to see it off. Dr. Markus Rex, a leader of the $155-million expedition, and the ship’s captain, Stefan Schwarze, were the last to board, lifted onto the foredeck in dramatic fashion by a crane. Half an hour later, the Polarstern slipped its moorings and eased out of the harbor, headed north.
Joined by a Russian icebreaker carrying more equipment, it will sail east for two weeks to the Laptev Sea, north of Central Siberia. There the Polarstern will churn through the pack ice and sidle up to an ice floe — a large expanse of intact ice, chosen on the spot after analysis of satellite radar images and other information — and cut its engine, allowing itself to be fully frozen in place. The Russian ship will transfer its equipment to the floe and turn around.
Deliberately trapped, if all goes well the Polarstern will travel with the ice along a wind-driven route known as the trans-polar drift toward and past the pole and eventually south, spilling out into the Fram Strait between Greenland and the Svalbard archipelago 12 to 14 months later.
“We’ll just go where the ice goes,” said Dr. Rex, a researcher in atmospheric physics at the Alfred Wegener Institute in Germany. Organized by the institute, the expedition involves scientists from 19 nations, including the United States, and has been five years in planning.
The Polarstern, the institute’s flagship, will become an itinerant research hub, the Multidisciplinary drifting Observatory for the Study of Arctic Climate, or Mosaic. Specialists in Arctic science — more than 60 at any time plus about 40 crew — will operate instruments on board and on the ice, with some autonomous equipment set up about 30 miles away.
The studies — of the atmosphere, ocean, ice and snow, and the interactions among them — are all focused on one goal: a better understanding of how warming will affect the region, now and into the future.
While the entire world is heating up, largely because of human activities that release greenhouse gases into the atmosphere, the Arctic is warming about twice as fast as other regions, and the effects are more noticeable there than anywhere else.
Among other impacts, the sea ice itself is changing, becoming less extensive and thinner as the Arctic warms. This year, with the summer melt season coming to an end, ice coverage is near the record low that was set in 2012, according to the National Snow and Ice Data Center in Colorado.
“We need to understand what is driving that rapid climate change,” Dr. Rex said, “and we need to have a solid basis of our modeling for the future.”
Current climate models vary greatly when it comes to predicting the future of the Arctic. Under some greenhouse gas emission scenarios, some models forecast regional warming of about 9 degrees Fahrenheit by the end of the century. But with other models the warming is much greater.
“That’s not a solid and robust enough basis for the important political decisions we have to take,” Dr. Rex said.
The uncertainty is a result of lack of data, said Allison Fong, a microbial oceanographer at the institute and leader of the expedition’s team that will study the ecosystem of the high Arctic, from bacteria and viruses in the water and ice to fish.
The polar Arctic is one of the most remote parts of the planet, accessible by ship for only a few months in the summer when much of the ice melts. “Most of the data we have comes from that very small portion of the year,” Dr. Fong said.
By drifting with the ice, the expedition should be able to obtain data throughout the annual cycle of sea ice growth and melt. “That’s one of the great things about Mosaic — we’re kind of nested there for the year,” she said.
Leaving a research ship to drift across the high Arctic for a year — which has only been done once before, by the Norwegian explorer Fridtjof Nansen aboard his wooden ship the Fram in the 1890s — presents enormous challenges, not the least of which is that for some weeks the expedition will be operating in polar darkness.
But even in daylight, trips on the ice will be tightly regulated and, with the potential for visits by polar bears, guards will be stationed with weapons to be used as a last resort. And many of the expedition participants have undergone survival or other specialized training.
Most scientists will work a two-month stint aboard the ship before being replaced, and the crew will be swapped halfway through. Restaffing and resupplying the Polarstern will require voyages of several weeks by other icebreakers from Russia and China and, sometime next year, by airplanes or helicopters when a runway is built on the ice floe near the ship.
Given the time, distance and expense involved in reaching it, the expedition has to be able to handle most problems — short of a life-threatening medical emergency — on its own. In a tour of the ship, Mr. Lauber, the first officer, pointed to one container as an example. Inside it were spare parts for the planes that would be arriving, so they would not be stranded in the event of a mechanical problem.
Jessie Creamean, a researcher from Colorado State University who will be studying how particles from seawater, ice and snow lead to cloud formation, brought extra spare parts for her air-sampling instruments, including a portable one she will take out onto the ice. “You really have to be prepared,” Dr. Creamean said. “Up there you can’t just order something from Amazon.”
Whether all the researchers are prepared for the isolation of being on a ship locked in the ice is another matter. Most have worked on Arctic or Antarctic expeditions before, though never for this long. The Polarstern has an exercise room and a small swimming pool, as well as a sauna and even a tanning bed to fight the effects of lack of sunlight.
Mr. Lauber said the sound of the ice pressing against the hull — a scraping noise that can reverberate throughout the ship — could bother some less-experienced members of the expedition. But they should be confident that the Polarstern will stand up to the conditions, he said. Its steel hull is up to three and a half inches thick and tapered so that the pressure of the ice forces the ship up, relieving some of the crushing force.
Choosing the right starting point so that the ship drifts for a full year, that it goes near or across the pole and that it emerges from the ice where the researchers want it to is another challenge. “We don’t want to end up in Canada,” Dr. Fong said. Ending up in a circulating current called the Beaufort gyre that would be practically impossible for resupply ships to reach “would be really bad,” she said. An expedition that lasted less than the full annual cycle would also be considered a failure.
To help ensure a good outcome, Thomas Krumpen, a senior scientist with the institute who will be one of the leaders of the expedition during a two-month stretch next year, analyzed ice movement from satellite observations over the past decade and a half. The result was a series of trajectories with different freeze-in points and good or bad end points.
Using that information, the expedition leaders are looking at sailing to a point in the Laptev Sea about 350 miles from the pole.
“Of course, this is a very statistical approach,” Dr. Krumpen said. There have been some years when the sea ice makes an early southward turn and exit. “It would be an exception, but in principle it could happen,” he said.
Once at the proper location, the expedition leaders would then look for a proper ice floe — large enough to accommodate an ice runway several miles long, thick enough to support experiments set up away from the ship, and of a shape that would be more stable and less likely to disintegrate during the year.
Dr. Fong said the floe selection process, which she will be involved in, is just one of many elements of a complex project where things can go wrong. In the end, she said, “we’re going to need ice, but we’re also going to need luck.”