The Arctic is undergoing rapid transformations due to climate change, shifting its landscape from ice-covered regions to water-based areas. This transition, driven by atmospheric and oceanic warming, is compounded by growing economic activity in the region, such as shipping routes and the exploitation of natural resources like oil and natural gas. The increasing use of Arctic passages like the Northwest Passage (NWP) and the Northeast Passage (NEP) has made the region more accessible, offering shorter shipping routes compared to traditional passages. However, the rise in shipping and resource extraction poses a severe threat to the delicate Arctic environment, particularly through vessel-source pollution, such as black carbon and underwater noise.
The Arctic is warming at a rate more than twice the global average, with temperatures expected to rise by 3 to 4°C in the next 50 years, according to a 2007 Intergovernmental Panel on Climate Change report. In recent decades, the area of Arctic sea ice remaining at the end of the summer melt season has declined 13 percent per decade relative to the 1981–2010 average. Although melting sea ice doesn’t directly contribute to rising sea levels, it accelerates ocean warming by replacing reflective ice with darker ocean surfaces that absorb heat rather than reflecting it. This disturbance of atmospheric and oceanic patterns contributes to stronger weather events, such as hurricanes.
Furthermore, the Arctic environment is uniquely vulnerable to pollution due to the ice-albedo feedback effect. Black carbon and other airborne pollutants, when deposited on sea ice, prevent it from reflecting sunlight, further accelerating the melting process. As economic activities like Arctic shipping increase, the concentration of such pollutants in the region has grown and these threats must be addressed.
Shipping traffic in the Arctic has significantly increased over the last 10 years, with a rise of 37 percent in the number of ships and a doubling of the total distance sailed in Arctic waters. The growing activity is largely attributed to large-scale resource projects, such as the Mary River Mine in Nunavut and the Yamal gas project, which have introduced more bulk carriers and gas tankers to the region. This uptick in maritime traffic has led to higher emissions of pollutants, including greenhouse gases (GHG), sulfur dioxide (SO2), nitrogen oxides (NOx), and black carbon.
Black carbon, a particulate pollutant generated by ship emissions, is a significant contributor to Arctic warming. When emitted, it settles on the sea ice, reducing the ice's reflective capabilities and accelerating the warming process.
The International Maritime Organization (IMO) has developed international regulations to address the growing environmental threats posed by Arctic shipping. A key convention, the International Convention for the Prevention of Pollution from Ships (MARPOL), plays a central role in addressing pollution from ships. Annex VI of MARPOL specifically deals with air pollution from ships, limiting emissions of NOx, sulfur oxides (SOx), and particulate matter. However, black carbon is notably absent from the annex’s specific provisions, despite its growing significance.
The Marine Environment Protection Committee (MEPC) of the IMO has recently taken steps toward regulating black carbon emissions from ships. In October 2023, the MEPC adopted two nonbinding resolutions—one that outlines best practices for reducing black carbon emissions in the Arctic and another that provides guidelines on monitoring, measuring, and reporting black carbon. Though these measures are a step in the right direction, they remain voluntary and lack enforcement power. The IMO has also urged member states and ship operators to voluntarily adopt cleaner fuels and propulsion technologies that could reduce black carbon emissions in Arctic waters.
Additionally, the IMO’s 2023 revised Initial Strategy on GHG Emissions from Ships aims to reduce international shipping emissions by 40 percent by 2030 compared to 2008 levels. This strategy, which includes actions to reduce black carbon, is a crucial part of the IMO's approach to mitigating climate change impacts in the Arctic.
Another important development is the Heavy Fuel Oil (HFO) amendment to MARPOL Annex I, which took effect on July 1, 2024. This amendment bans the use of HFO in Arctic waters, although exemptions exist. For example, vessels with compliant fuel tank designs under the Polar Code and ships with waivers from Arctic coastal nations can still use HFO until 2029. This is part of the broader goal to phase out harmful fuels from Arctic shipping, in line with environmental and climate objectives.
One of the most important tools in the IMO’s regulatory toolkit is the establishment of Emission Control Areas (ECAs). These are designated zones where stricter measures are applied to limit pollutants like SOx, NOx, and particulate matter. In March 2024, the IMO officially recognized ECAs in the Canadian and Norwegian Arctic waters, which will help reduce black carbon emissions by up to 25 percent. The goal is to expand these ECAs to the broader Arctic region, further curbing pollution in vulnerable areas.
Despite significant progress in addressing airborne pollutants, underwater noise pollution remains largely unregulated. The Arctic Ocean presents a unique acoustic environment due to its ice-covered waters, where sound travels differently than in temperate oceans. Anthropogenic noise from ships, particularly in the Arctic, can travel long distances and disrupt marine life. Studies show that noise levels in the Arctic increased significantly between 2013 and 2019, doubling or tripling in some areas.
Marine mammals, such as whales and seals, rely on sound for communication, navigation, and hunting. Increased noise from ships interferes with these vital functions, causing stress and even physical harm. For instance, in the Canadian Arctic, studies have shown that narwhals exposed to shipping noise experience stress levels 200 percent higher than normal. Moreover, ships pose a direct danger to marine mammals through vessel strikes and entanglement in fishing gear, both of which contribute to the declining health of Arctic species.
Despite these threats, international legal frameworks have failed to adequately address underwater noise pollution. The International Convention for the Safety of Life at Sea (SOLAS) and other IMO guidelines only focus on noise pollution aboard vessels, and IMO’s 2014 guidelines for reducing underwater noise are nonbinding. IMO has also issued recommendations for creating Particularly Sensitive Sea Areas (PSSAs) where shipping activities could be restricted to protect vulnerable marine ecosystems, but the Arctic has not yet been designated as a PSSA.
IMO’s Sub-Committee on Ship Design and Construction did make some progress in January 2024 by agreeing to take action to reduce underwater noise pollution from shipping, but the recommendations remain voluntary. IMO continues to seek data from the shipping industry on how to best mitigate noise pollution in Arctic waters.
To protect the Arctic, it is essential to adopt a comprehensive approach that addresses both black carbon and underwater noise. Policies to consider include:
The Arctic is one of the most fragile and important ecosystems on Earth, and its protection requires robust international action. While IMO has made significant progress in addressing black carbon and other pollutants, much more needs to be done, especially in terms of regulating underwater noise. The shipping industry, supported by international law and regulation, must act swiftly and responsibly to minimize its impact on the Arctic environment. With the right legal frameworks in place, the Arctic can be safeguarded for future generations, ensuring the health of its ecosystems and the sustainability of its economic activities. The path forward is clear, but continued efforts and collaboration are essential to ensure that the shipping industry can meet the growing regulatory demands and help protect the Arctic marine environment.
