File photo of a ship navigating between icebergs near Greenland in the Arctic taken August 15, 2023.

When a Russian gas tanker sliced through the icy waters of the Arctic in the middle of winter four years ago, it became clear global shipping routes would be forever changed.

The Christophe de Margerie vessel, named after the former CEO of French oil company Total, made its way from eastern China through the Bering Sea, eventually docking at a remote Arctic port in Siberia in February 2021 .

For the first time in history, global warming caused by humans allowed a ship to navigate through Arctic winter ice.

The Arctic has been warming four times faster than anywhere else on the planet since 1979, according to multiple scientific studies . Melting sea ice is opening up paths for increased shipping and other vessel traffic in the region, especially along the Northern Sea Route, the Arctic shortcut between Europe and Asia that stretches more than 9,000 kilometres .

Shipping seasons are also being prolonged as a result of the warming climate.

But with more traffic comes more environmental degradation. The consequences are dire, particularly for climate heating, loss of biodiversity and pollution. And since the Arctic is a key regulator of the Earth’s climate, what happens in this region can be felt thousands of kilometres away.

A vicious cycle

It’s a vicious cycle. As sea ice melts and opens new routes for maritime traffic in the Arctic, the environmental fallout caused by vessels burning fossil fuels adds to global warming, which in turn melts more sea ice.

A perfect example of this is black carbon. It’s a sooty material emitted from gas and diesel engines that aren’t completely combusted. Not only does black carbon pollute the air with particulate matter, but because of its ability to absorb light as heat, it contributes to climate change by warming the air.

When black carbon is deposited on ice in the Arctic, it takes away its ability to reflect heat.

“The black colour deposited on the white ice means the ice then absorbs more sunlight, leading to more melting,” explained Sammie Buzzard, a polar scientist at the Centre for Polar Observation and Modelling at Northumbria University.

Read moreArctic scientists race against the clock as ‘ice memory’ melts away

The use of heavy fuel oil, leftovers from the bottom of the barrel that lead to high black carbon emissions, grew by 75 percent in the Arctic in just four years, between 2015 and 2019. On the opposite end of the planet, in Antarctica, its use has been banned since 2011.

Black carbon is one of the most significant contributors to climate change, after CO2.

“Lots of Arctic ice gets covered, and anything that changes the colour of the ice or causes it to melt also removes a key part of the ecosystem,” Buzzard said.

Busy routes

Almost all types of maritime traffic are on the rise in the Arctic, whether for tourism or transportation. Fishing boats are by far the most common type on ship in the Arctic, followed by cargo ships and bulk carriers. Between 2013 and 2023 , every type of ship aside from oil tankers and research vessels took to the Arctic in higher numbers.

Not only are there an increasing number of ships in the Arctic Ocean, but they are also navigating over greater distances. In the span of a decade, the total distance vessels covered more than doubled, with an increase of 111 percent .

The area for ships to move safely in open waters of the Arctic route during a 90-day safety window expanded by 35 percent from 1979 to 2018. Every year, the area keeps growing. It’s estimated that five percent of global shipping traffic will be diverted to the Arctic route as a result.

Usually, navigating the frozen waters of the Arctic requires an escort well-versed in icebreaking. A boat designed to break open large chunks of ice glides alongside vessels that need to make it through one of the three main shipping routes: the Transpolar Sea Route, the Northwest Passage or the Northern Sea Route.

But according to climate projections, unescorted navigation could be possible as early as 2030 in the summer months.

Arctic shipping routes. © FRANCE 24’s graphic design studio

In the Canadian Arctic, where the Northwest Passage is located, the number of vessels has quadrupled since 1990.

But the exact number of weeks ships can navigate safely through the route is dwindling. Research has found that melting sea ice doesn’t necessarily make all Arctic sea routes more accessible. Thin sea ice does indeed melt under global warming, but centuries-old floes break off and are released into the Arctic Ocean, moving southwards and creating choke points, which makes some key points in the Northwest Passage more dangerous and unpredictable.

Still, the overall trend is alarming. Melting sea ice brought on by global warming allowed shipping traffic to increase by 25 percent between 2013 and 2019.

The butterfly effect of the Arctic

The Arctic helps keep the planet’s climate in balance. As sea ice perishes and maritime traffic increases, further accelerating global warming, environmental consequences become ever more far-reaching.

“The polar regions act to help cool the rest of the planet through the white ice reflecting energy from the sun back to space,” Buzzard explained. “They act a bit like a giant freezer for the rest of the planet.”

This has an effect on global temperature. “Sea ice regulates heat exchange between the atmosphere and ocean, impacting the global circulation of heat,” said Buzzard. “[So] anything that reduces the amount of ice, or darkens it, can mean less energy is reflected, which means extra warming, which then has consequences for the entire planet.”

Some changes are being implemented to slow down this worrying feedback loop. A ban on heavy fuel oil, which releases black carbon, was introduced in July 2024 , though some vessels can continue to use it until July 2029.

The UN agency responsible for regulating maritime transport, the International Maritime Organization (IMO), also pledged to reduce emissions by at least 20 percent in the next five years.

But the Clean Arctic Alliance, a group of 21 NGOs who advocate for government action to protect the Arctic’s wildlife and its people, insists there is not enough being done to curb the rise of black carbon and methane pollution from shipping in the Arctic. Its lead advisor, Sian Prior, said that “in recent years, black carbon emissions from Arctic shipping have more than doubled,” in a statement published on 14 May.

For Buzzard, the economic interests of using Arctic shipping routes may be beneficial. But increased traffic must be coupled with strict environmental regulations.

“While there can be a saving both in terms of carbon and time for ships to travel across the Arctic, this is a very fragile ecosystem that is already struggling to cope with changes from human-created climate change,” she said.

“Sea ice not only acts to help cool the planet, it is a habitat for creatures like polar bears that use the ice for hunting,” Buzzard noted. The polar bear, now a mascot for environmental issues in the Arctic, relies on sea ice to hunt and move around to find crucial denning areas. It accounts for over 96 percent of the animal’s critical habitat.

Increased traffic also brings noise pollution, which disturbs mammals who travel through these frozen waters, like whales. Pods use sound to find their food, mates, avoid predators and migrate. A recent study found that underwater noise in some places in the Arctic Ocean has doubled in just six years because of increased shipping.

The list of environmental consequences of the maritime traffic boom in the Arctic goes on. Vessels navigating through the Arctic also release air pollutants, flush out sulphur oxide into the ocean through scrubbers that remove the substance from a ship’s exhaust, and can leave behind litter.

“There is also the increased risk of pollution from oil spills,” added Buzzard.

As countries such as Russia and China eye the prospect of new exploitation that comes with melting sea ice, and US President Donald Trump covets the resource-rich island of Greenland , time is running out for this fragile environment.

“There needs to be careful regulation to minimise the [environmental] impacts to the area,” stressed Buzzard. “The consequences won’t just stay in the Arctic.”