Reykjavik, Iceland — As rising global temperatures accelerate the melting of sea ice in the Arctic Ocean, this has sparked a boom in ships taking routes that were previously frozen and impassable.

The increase in maritime Arctic traffic, which received increased attention as president Trump advocated for the United States to take over Greenlandit came with big environmental costs: black carbon, or soot, that spews from ships and makes the ice melt even faster. At meetings this week with international maritime regulators, several countries are pushing for ships in the Arctic to use cleaner fuels that cause less pollution.

Glaciers, snow and ice covered with soot emitted by ships have less ability to reflect the sun. Instead, the sun’s heat is absorbed, helping to make the Arctic the fastest-warming place on Earth. On the other hand, the melting of the ice in the Arctic can affect the weather around the world.

“It ends up in a never-ending cycle of increased warming,” said Sian Prior, general counsel for the Clean Arctic Alliance, a coalition of nonprofits focused on the Arctic and shipping. “We need to regulate emissions and black carbon, in particular. Both are completely unregulated in the Arctic.”

In December, France, Germany, the Solomon Islands and Denmark proposed that the International Maritime Organization require ships traveling in Arctic waters to use “polar fuels”, which are lighter and emit less carbon pollution than widely used marine fuels known as residues. The proposal includes steps companies would need to take to comply and the geographic area it would apply to – all ships traveling north of the 60th parallel. The proposal is expected to be presented to the IMO’s Pollution Prevention and Response Committee this week, and possibly to another committee in April.

A 2024 ban on the use of a type of residue known as heavy fuel oil in the Arctic has so far had only a modest effect, partly due to loopholes in the law.

“Black carbon” exacerbates other regional issues

The push to reduce black carbon, which studies have shown has a warming effect 1,600 times greater than carbon dioxide over a 20-year period, comes at a time of conflicting interests, both internationally and among countries with Arctic shores.

In recent months, Mr. Trump’s occasional comments about the need to “own” Greenland to bolster US security have raised many issues, from Greenland’s sovereignty to the future of the NATO alliance. Pollution and other environmental issues in the Arctic are on the back burner.

Mr. Trump, who called climate change “fraudulent business,” also opposed global policies aimed at combating it. Last year, the IMO was expected to adopt regulations that would impose carbon fees on shipping, which supporters said would encourage companies to use cleaner fuels and electrify fleets where possible. Then Mr. Trump intervened, lobbying hard for nations to vote no. The measure has been postponed for a year, and its prospects are uncertain at best. That being said, it is hard to see the IMO moving forward quickly on the current proposal to limit black carbon in the Arctic.

Even within Arctic nations, which are most affected by black carbon and other pollution from ships, there are internal tensions over such regulations. Iceland is a good example. Although the country is a world leader in green technologies such as carbon capture and the use of thermal energy for heating, conservationists say the country has made less progress in regulating pollution in its seas. This is because the fishing industry, one of the most important in the country, has a huge impact.

“The industry is happy with profits, unhappy with taxes and doesn’t deal with issues like climate or biodiversity,” said Arni Finnsson, chairman of the board of the Icelandic Association for Nature Conservation.

Finnsson added that the costs of using cleaner fuels or electrifying fleets also fueled resistance.

“I think the government is waking up, but they still have to wait for the (fishing) industry to say yes,” he said.

The country has not taken a position on the pending polar fuels proposal. In a statement, Iceland’s Ministry of Environment, Energy and Climate said the proposal was “positive in terms of its purpose and basic content” but that further study was needed. The statement added that Iceland supports stronger measures to curb emissions from maritime traffic and reduce black carbon.

More maritime traffic means more soot in the air

Soot pollution has increased in the Arctic as cargo ships, fishing boats and even some cruise ships increasingly travel in the waters connecting the northernmost parts of Iceland, Greenland, Canada, Russia, Norway, Finland, Sweden and the United States.

Between 2013 and 2023, the number of ships entering waters north of the 60th parallel increased by 37%, according to the Arctic Council, an intergovernmental forum made up of eight countries with territory in the Arctic. In the same period, the total distance traveled by ships in the Arctic increased by 111%.

Black carbon emissions have also increased. In 2019, 2,696 metric tons of black carbon were released from ships north of the 60th parallel, compared to 3,310 metric tons in 2024, according to a study by Energy and Environmental Research Associates. The study showed that fishing boats are the biggest source of black carbon.

It also found that banning fuel oil in 2024 would result in only a small reduction in black carbon. Waivers and exceptions allow some ships to continue using it until 2029.

Environmental groups and concerned countries see marine fuel regulation as the only way to realistically reduce black carbon. This is because getting states to agree to limit traffic would probably be impossible. The lure of fishing, resource extraction and shorter shipping distances is too great. Ships can save days on some journeys between Asia and Europe by sailing through the Arctic.

However, the path known as the Northern Sea Route is passable only a few months of the year, and then ships must be escorted by icebreakers. Those dangers, combined with concerns about Arctic pollution, have some companies vowing to stay away — at least for now.

“The Arctic debate is heating up, and commercial ships are part of that debate,” Søren Toft, CEO of Mediterranean Shipping Company, the world’s largest container shipping company, wrote in a LinkedIn post last month. “Our position at MSC is clear. We do not and will not use the Northern Sea Route.”