Polar Code

Black carbon (soot) is produced when fossil fuels burn, for example in diesel engines and generators on ships. These microscopic particles can settle on snow and glaciers, darkening their surface, making them melt more quickly, and speeding up the process of sea level rise.

A 2022 study found elevated concentrations of black carbon in the snow around popular Antarctic tourism sites and research stations, when compared to other areas of Antarctica. Increased black carbon was linked to more rapid snow melt and loss of snowpack in the affected areas (source).  

ASOC advocates for effective regulation of black carbon emissions at meetings of the International Maritime Organization, and supports the efforts of Antarctic Treaty Parties to monitor the carbon footprint of Antarctic activities, including black carbon, with a view to systematically reducing carbon emissions and local black carbon pollution from all activities in the Antarctic.

Download our black carbon infographic.

Read our information papers: 

Shipping vessel safety, environmental protection and the Southern Ocean (2025). 

Carbon Footprints of Antarctic Activities (2023). 

Near-term Antarctic Impacts of Black Carbon and Short-lived Climate Pollutant Mitigation (2014). 

Black carbon and other short-lived climate pollutants: impacts on Antarctica (2013).

Reducing black carbon emissions from vessels in the Polar Regions (2011).

Black water 

Under the Polar Code, dumping of raw, untreated sewage is permitted beyond 12NM (13 miles) from land, ice shelves or fast ice, and as far as practicable from areas of sea ice concentration exceeding a density of one in ten. This could result in raw sewage being inadvertently dumped in an important feeding ground for Antarctic wildlife. ASOC advocates for stronger regulations to protect vulnerable ecosystems, including no dumping of untreated sewage in the Southern Ocean.

Gray water 

There are no restrictions on the dumping of untreated gray water, which can contain high levels of chemical detergents including nitrates and phosphates, heavy metals, fecal coliforms, polyaromatic hydrocarbons and microplastics. 

ASOC advocates for the discharge of gray water to be regulated globally through the IMO’s MARPOL Convention, with special restrictions provided for the Southern Ocean in the Polar Code.

Download our gray water infographics:

Gray water from Antarctic vessels.

Gray water and microplastics pollution: the problem & the solution

Read our information papers:

Antarctic wastewater: a direct, local and avoidable source of non-native species (2025)

Unregulated discharges in the Antarctic Treaty area: gray water from ships (2024)

While the Polar Code provides legally binding regulations for the design and conduct of vessels in polar waters, these provisions must be interpreted and implemented by each IMO Member State with vessels operating in the polar regions. 

ASOC encourages Antarctic Treaty Parties to report their shared experience, best practices, and lessons learned while implementing the Polar Code and international meetings. 

To facilitate the flow of information between global and Antarctic-focused intergovernmental forums, ASOC submits information papers summarizing relevant projects, initiatives and other developments related to the implementation of the Polar Code, which may be happening in other meetings. 

Many provisions of the Polar Code apply to both Arctic and Antarctic waters, and while these regions are similar in many ways, they differ in important ways as well. ASOC advises Antarctic Treaty Parties to share their experiences of implementation, as well as any gaps or challenges they have observed, at meetings of the IMO’s Maritime Safety Council and the Arctic Council. In addition to supporting the harmonized implementation of the Polar Code across both polar regions, this will help ensure that the Polar Code is fit for purpose in, and offers the best possible protection for the Antarctic, and those who live and work there.

Read our information papers:

Shipping vessel safety, environmental protection and the Southern Ocean (ATCM 2025)

New mandatory requirements on navigation and voyage planning for fishing vessels operating in polar waters and other vessel matters (CCAMLR 2025)

Harmonised implementation of the Polar Code and related shipping Issues (ATCM 2024)

Improving safety and reducing environmental impact of CCAMLR fishing vessels (CCAMLR 2023)

Improving safety and environmental protection of shipping in the Antarctic Treaty Area (ATCM 2023)

Many marine animals rely on sound to survive, using it to communicate, find food, avoid predators, and navigate. The impact of underwater noise is amplified in the polar regions, where historically there has been little shipping traffic, and ice cover can affect how the sound travels. 

In 2014 the IMO developed non-mandatory guidelines to reduce the impact of underwater noise from shipping on marine animals, but found there was poor uptake of the guidelines. 

Working with other environmental NGOs, ASOC contributed to a revision of the guidelines in 2023, and continues to pursue mandatory regulations, which will require ships to develop noise management plans and reduce the impact of ships operations on marine wildlife.

Read our information paper: 

Improving Safety and Environmental Protection of Shipping in the Antarctic Treaty Area (2023).

Focus Area: Abandoned, lost, and discarded fishing gear (ALDFG)

Over 800 miles (roughly 1300 kilometers) of fishing line equipped with thousands of baited hooks has been lost in the Southern Ocean over only two fishing seasons. 

ASOC supports proposals by the IMO’s Marine Environment Protection Committee (MEPC) that fishing gear should be marked, so that lost gear can be traced back to its owners, and that fishing vessels should be required to report any unintended losses of fishing gear on the high seas.

ASOC also reports to CCAMLR on developments at meetings of the IMO, encouraging Members to support the IMO’s work in the CCAMLR Area. ASOC called on CCAMLR to “contribute to the IMO’s work to ensure that a regulation is included in MARPOL Annex V on the marking of fishing gear and efforts to progress and finalize the work on mandatory reporting mechanisms for accidentally lost or discharged fishing gear.”

To raise awareness of the threat and solutions to ALDFG and plastic pollution in the Southern Ocean and further afield, ASOC has supported the preparation of several new infographics. Download our infographics:

• Ghost gear.
• Plastic pollution.
• Microplastics from marine paints.

Read our information papers: 

Shipping vessel safety, environmental protection and the Southern Ocean (ATCM 2025)

Improving safety and environmental protection of shipping in the Antarctic Treaty Area (ATCM 2023)

In 2020, researchers identified 14 non-native species around the Antarctic Peninsula, both marine and terrestrial, and 13 more at high risk of invading the region (source). 

Focus Area: Ballast water

Many ships carry ballast water in ballast tanks to help them remain stable, particularly when they are not carrying cargoes. Ballast water is pumped into tanks from the ocean and contains plants, small animals, viruses and bacteria, often from a range of ports and locations. When it is discharged in Antarctic waters it can introduce invasive aquatic species to fragile polar ecosystems.

The journey towards effective ballast water management in the Antarctic Treaty area has been a long one, which continues today. 

Before 2017 there was effectively no regulation of ballast water exchange in the Antarctic Treaty Area. There was a suite of ‘recommendatory measures’ under the IMO’s Ballast Water Management Convention, which were reinforced in the Polar Code. Under these guidelines vessels were recommended to take measures to minimize the risk of invasive aquatic species through ships’ ballast water and biofouling. 

These Guidelines were an effective stopgap, introducing a regional strategy with voluntary guidelines for ballast water exchange before entering the Antarctic Treaty Area. 

The Ballast Water Management Convention (BWMC) , which finally took effect on 8th September, 2017, requires all ships to have a ship-specific Ballast Water Management Plan, a Ballast Water Record Book and an International Ballast Water Management Certificate (the Certificate applies only to ships of 400gt and above). 

The provisions of the Convention will be phased in gradually over eight years. From 8 September 2024, all ships must meet an international standard which specifies the maximum number of viable organisms allowed to be discharged. In most cases this will require a ballast water management system to be installed. 

View infographic on Complying with the Ballast Water Management Convention. 

Read the IMO’s guidelines for implementing the BWMC which came into force in September 2017. Read now. 

Read the 2023 ASOC Information Paper: Improving Safety and Environmental Protection of Shipping in the Antarctic Treaty Area.