In a few days, one of the world’s largest cruise ships, the Crystal Serenity, will visit the tiny Inuit village of Ulukhaktok in northern Canada. Hundreds of passengers will be ferried to the little community, more than doubling its population of around 400. The Serenity will then raise anchor and head through the Northwest Passage to visit several more Inuit settlements before sailing to Greenland and finally New York.

It will be a massive undertaking, representing an almost tenfold increase in passenger numbers taken through the Arctic on a single vessel – and it has triggered considerable controversy among Arctic experts. Inuit leaders fear that visits by giant cruise ships could overwhelm fragile communities, while others warn that the Arctic ecosystem, already suffering the effects of global warming, could be seriously damaged.

“This is extinction tourism,” said international law expert Professor Michael Byers, of the University of British Columbia. “Making this trip has only become possible because carbon emissions have so warmed the atmosphere that Arctic sea ice in summer is disappearing. The terrible irony is that this ship – which even has a helicopter for sightseeing and a huge staff-to-passenger ratio – has an enormous carbon footprint that is only going to make things even worse in the Arctic.”

The Serenity is by far the biggest cruise vessel to traverse the fabled Northwest Passage, whose exploration has claimed the lives of hundreds of seamen. The ship has a crew of 655 and carries 1,070 passengers, who have paid between £19,000 and £120,000 for a voyage that Crystal Cruises says will take them on an “intrepid adventure” from Anchorage in Alaska to New York over 32 days.

For its part, Crystal insists its clients will have to follow a strict code of conduct during shore visits, while the ship’s air, water and rubbish discharges will be tightly controlled. Only low-sulphur fuel will be burned in the Serenity’s engines, said a spokesman. The Serenity will be accompanied by the UK icebreaker the RSS Ernest Shackleton, he added.

However, it is not the voyage that directly poses danger, Byers said. “This is a well-supported, carefully worked-out trip. I acknowledge that. The trouble is that it is going to open the door to mass tourism in the high Arctic and many other operators – who could easily turn out to be far less scrupulous or painstaking – will be eyeing it up for major operations. That could end in disaster. ”

This point was backed by Okalik Eegeesiak, chair of the Inuit Circumpolar Council. “Far too many people will be descending suddenly into these communities and bringing far too much garbage with them,” she told the Observer.

“These places lack the infrastructure and the training to deal with the incredible numbers of people that will start arriving on these boats.” Apart from Ulukhaktok, the Serenity is also scheduled to visit the Inuit communities of Pond Inlet, Cambridge Bay and Sisimiut.

Eegeesiak added that the Inuit were already experiencing problems thanks to global warming. As sea ice disappears, this removes a highway on which locals can ride their snowmobiles and dog sleds to hunt and visit friends. Disappearing ice means increasing fragmentation of communities and limits the ability of people to hunt, a problem that is only likely to worsen as the region’s shrinking ice-cap opens it up to mining, oil drilling, tourism and more shipping.

In addition, there is the question of food. The Inuit have no farms and rely on what they can catch from the ice and water around them for sustenance. But this food chain is under threat. Algae grows on the underside of sea ice and is eaten by krill, which is then eaten by Arctic cod, which in turn is eaten by seals and finally polar bears. However, if the bottom rung of this food chain disappears because sea ice is melting, then all sorts of unintended consequences could soon be realised, marine biologists have warned. Mass tourism is only going to make this worse, they add.

This point was stressed by Eegeesiak. “It is not just the communities we need to worry about when these great boats arrive but all the wildlife of the region,” she said.

Earlier this month Crystal announced that it was already taking bookings for a similar 32-day cruise through the Northwest Passage for 2017. In addition, it revealed it has ordered construction of “the world’s first purpose-built polar class megayacht, the Crystal Endeavour”. The ship – which will cruise exclusively in the Arctic and Antarctic – will carry underwater scooters to allow passengers to experience their own subsea exploration and will be fitted with some of the largest bedroom suites ever put in a cruise ship. “This megayacht will change the game entirely – the possibilities for expedition travellers will be virtually limitless,” said Crystal president Edie Rodriguez.

But such an opening up of the Arctic to tourism dismays Byers. “One big ship is perhaps manageable but five or six is tempting disaster. Glaciers are crumbling more and more up there and we are getting more and more icebergs in the water.

“If a ship carrying 3,000 passengers hits one of those you could be in real trouble. This is an incredibly remote region. It could take two days to get search-and-rescue helicopters up there. Yet an accident like that is almost inevitable.”