IMO and its role in protecting the world's oceans


IMO at the UN Ocean Conference

IMO was at the 2022 UN Ocean Conference in Lisbon (Portugal). 

World Oceans Day 2022

World Oceans Day was celebrated on 8 June 2022. IMO is working to help protect the ocean through several projects around the world. 


IMO's role in protecting the world's oceans

The world's oceans are one of our planet’s most valuable environmental resources. Seas cover around 70% of the world’s surface, providing raw materials, energy, food, employment, a place to live, a place to relax and the means to transport more than 80% of global trade by volume. Shipping is a key user of the oceans, delivering essential goods and commodities, taking ferry passengers to their destinations and carrying millions of tourists on cruises. 

As the United Nations agency responsible for developing and adopting measures to improve the safety and security of international shipping and to prevent pollution from ships, and for the prevention of pollution by dumping of waste at sea, IMO has an integral role in meeting the targets set out in the United Nations Sustainable Development Goal (SDG) 14: Conserve and sustainably use the oceans, seas and marine resources for sustainable development. IMO's work  is also linked to  many other SDGs  too, for example SDG 13 on climate action, since the oceans are impacted by increasing carbon dioxide (CO2) and other greenhouse gas emissions (GHG) from human activities, but also SDGs 6 and 9, aiming at a sustainable society, with infrastructure, transportation and waste management that can support societies now and in to the future.  

IMO has over many decades developed and adopted mandatory rules, as well as recommendations and guidelines, to protect the marine environment from any potential negative impact of shipping activities. One of the key conventions protecting the oceans is the International Convention for the Prevention of Pollution from Ships (MARPOL). MARPOL was first adopted in 1973 with annexes covering  the prevention of pollution from ships by oil, by chemicals carried in bulk, by packaged goods, by sewage and garbage from ships. The convention was expanded in 1997 to regulate air pollution and emissions from ships.  

Other IMO treaties cover oil pollution preparedness, response and co-operation, control of harmful anti-fouling systems on ships, prevention of the potentially devastating effects of the spread of invasive harmful aquatic organisms carried by ships’ ballast water, and safe and environmentally sound recycling of ships, to name just a few. And  just as the  how the oceans are linked to  coastal and on - land activities,  IMO's work to protect our oceans  goes beyond the ships, by regulating  the prevention of pollution from dumping at wastes at sea, including climate change mitigation options such as carbon capture and storage. This is done through two treaties known as the London Convention and Protocol

IMO understands the need for special protection in some areas because of ecological, socio-economic or scientific significance. Special areas and Particularly Sensitive Sea Areas (PSSAs) are designated to ensure higher levels of protection from shipping activities. 

IMO continues to enhance its work on climate change mitigation and reduction of emissions from ships, which will contribute to reducing ocean acidification. IMO is working to reduce marine plastic litter and to mitigate against invasive aquatic species. IMO measures protect marine mammals from ship strikes and guidance has been adopted to reduce underwater noise from ships. 

Several global partnership projects executed by IMO address a range of ocean issues, including action on marine litter, reduction of GHG from shipping to address climate change as well as projects targeting the spread of potentially invasive aquatic species. 

Coordination and collaboration  is  key in all ocean matters. IMO is the secretariat for the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP), which is an inter-agency mechanism providing independent scientific advice to its ten sponsoring UN organizations. IMO is also playing an active role in other environmental cooperation mechanisms in the UN, such as UN-Oceans and the UN Environment Management Group (UN EMG).  

Read more below. 

Particularly Sensitive Sea Areas

IMO has a process to designate Particularly Sensitive Sea Areas (PSSAs), which are subject to associated protective measures such as mandatory ship-routeing systems. There are currently 15 areas (plus two extensions) protected in this way, including those covering UNESCO World Heritage Marine Sites, such as the Great Barrier Reef (Australia), the Galápagos Archipelago (Ecuador), the Papahānaumokuākea Marine National Monument (United States), and the Wadden Sea (Denmark, Germany, Netherlands).

This long-established practice of designating Special Areas and PSSAs fully supports the SDG 14 target to increase coverage of marine protected areas.

Click here or on the image below to read about Particularly Sensitive Sea Areas (PSSAs). 


Special Areas

MARPOL recognizes the need for more stringent requirements to manage and protect so-called Special Areas, due to their ecology and their sea traffic.

A total of 19 Special Areas have been adopted. They include enclosed or semi-enclosed seas, such as the Mediterranean Sea, Baltic Sea, Black Sea and Red Sea areas, and much larger ocean expanses such as the Southern South Africa waters and the Western European waters.

This recognition of special areas, alongside global regulation, is a clear indication of a strong IMO awareness of – and total commitment to – the fundamental importance of protecting and preserving the world's seas and oceans as vital life support systems for all peoples.

The Antarctic has enjoyed Special Area status since 1992. Oily discharges into the sea and garbage disposal overboard are totally prohibited. Read more about the Polar Code here

Marine litter

Marine litter presents a huge problem in our oceans, with some scientists warning that, by 2050, the quantity of plastics in the oceans will outweigh fish.

But IMO and others have been taking action to address the problem, including regulating the discharge of garbage from ships and supporting research work.

In 2021, IMO adopted the IMO Strategy to Address Marine Plastic Litter from Ships, with a vision to "strengthen the international framework and compliance with the relevant IMO instruments, endeavouring to achieve zero plastic waste discharges to sea from ships by 2025". This followed the adoption, in 2018, of an Action Plan to address marine plastic litter from ships. This plan aims to enhance existing regulations and introduce new supporting measures to reduce marine plastic litter from ships.

Read more here

Click to watch the video on how IMO helps make sure the oceans are clean and tidy:


As part of the action plan, IMO will look into the availability and adequacy of port reception facilities; consider making marking of fishing gear mandatory, in cooperation with the Food and Agriculture Organization (FAO); promote reporting the loss of fishing gear; facilitate the delivery of retrieved fishing gear to shore facilities; review provisions related to the training of fishing vessel personnel and familiarization of seafarers to ensure awareness of the impact of marine plastic litter; consider establishing a compulsory mechanism to declare loss of containers at sea and identify number of losses; and look at ways to enhance public awareness of the marine plastic litter issue.

GloLitter project

IMO and the Food and Agriculture Organization of the United Nations (FAO) have launched the GloLitter project, with initial funding for the project from the Government of Norway, to help shipping and fisheries move to a low-plastics future. GloLitter will assist developing countries to identify opportunities to prevent and reduce marine plastic litter, including plastic litter, from within the maritime transport and fisheries sectors, and to decrease the use of plastics in these industries, including identifying opportunities to re-use and recycle plastics.

Read more about IMO’s work on marine litter here.

Protecting the Arctic and Antarctic

Polar waters benefit from special measures under the IMO Polar Code, which entered into force on 1 January 2017 for ships operating in both Antarctic and Arctic waters.

Prevention of pollution from ships

The International Convention for the Prevention of Pollution from Ships, universally known as MARPOL, is the key treaty adopted by IMO to prevent and minimise pollution from shipping. 

MARPOL addresses pollution by oil from ships (covered in Annex I); also noxious liquid substances, such as chemicals, carried in bulk (Annex II); harmful substances carried in packaged form (Annex III); sewage discharges into the sea (Annex IV); and the disposal at sea of ship-generated garbage (Annex V).

Annex VI deals with atmospheric pollution from ships. In 2011, IMO became the first international regulator for a transport sector to adopt globally-binding energy-efficiency requirements, which apply to all ships globally, regardless of trading pattern or flag State, aimed at reducing greenhouse gas emissions from international shipping.

Other treaties address anti-fouling systems used on ships, the transfer of alien species by ships’ ballast water and the environmentally sound recycling of ships.

50 years together  - over the past five decades, IMO, governments and industry have worked together to achieve a dramatic and sustained reduction in major oil spills from ships; and have established effective systems for preparedness and response if there is an incident and created a comprehensive mechanism for providing compensation to those affected. Click to view the timeline and panels from an exhibition at IMO Headquarters.

Protecting marine biodiversity

IMO’s work to support marine biodiversity includes measures to prevent the spread of potentially invasive aquatic organisms.

Click for information on ballast water management (BWM) and biofouling.  

GloFouling partnerships project

IMO is executing the GEF-UNDP-IMO GloFouling Partnership project to address the transfer of harmful aquatic species through biofouling in some of the developing regions of the world.

Watch the video here and find out more about biofouling and the GloFouling Partnerships project. 

The project is driving actions to implement the IMO Guidelines for the control and management of ships' biofouling GloBallast Programme

Developing a new global oceans treaty

IMO participates in the Intergovernmental Conference on an international legally binding instrument under the United Nations Convention on the Law of Sea on the conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction. Read more:

Protecting marine mammals

IMO’s work on ship safety and prevention of pollution supports the protection of marine mammals.

IMO has adopted various ship routeing measures to protect whales and other cetaceans from ship strikes during breeding seasons, as well as guidance on how to minimize the risk for  ship strike. 

Click to read the article: Routing for Whales.

Underwater noise

A significant portion of the underwater noise generated by human activity may be related to commercial shipping. The international community recognizes that underwater-radiated noise from commercial ships may have both short and long-term negative consequences on marine life, especially marine mammals. 

IMO has issued guidance on reducing underwater noise from commercial shipping, to address adverse impacts on marine life.

IMO has begun work to review the guidance. Read more here: Ship noise.

Climate change mitigation

Increased carbon dioxide in the atmosphere can lead to ocean acidification. In 2011, IMO became the first international regulator for a transport sector to adopt globally-binding energy-efficiency requirements, which apply to all ships globally, regardless of trading pattern or flag State, aimed at reducing greenhouse gas emissions from international shipping. The mandatory energy-efficiency measures to reduce emissions of greenhouse gases from international shipping, under Annex VI of IMO's pollution prevention treaty (MARPOL), came into force in 2013 and have been subsequently strengthened.

IMO's GHG reduction strategy

In 2018, IMO Member States adopted an initial IMO strategy on reduction of GHG emissions from ships, setting out a vision which confirms a commitment to cutting GHG emissions from international shipping and to phasing them out as soon as possible.

There’s a specific linkage to the Paris Agreement, and clear levels of ambition – including at least a 50% cut in emissions from the sector by 2050, compared to 2008. To achieve the specified targets, ships currently at sea would have to reduce their emissions by more than 80%. The agreed reduction targets signify a tangible trajectory towards the decarbonisation of shipping. Therefore, low or zero-emission ships should be built well before 2050, hopefully by 2030.

Read more on IMO's work to cut GHG emissions from ships.

Shipping will undoubtedly need new technologies, new fuels and innovation to meet the GHG targets. There needs to be investment in R&D, infrastructure and trials. A range of IMO-executed projects are addressing this, focusing on supporting developing countries to implement MARPOL Annex VI energy efficiency measures and promoting trials and training. 

Read more about IMO's global projects under the Department of Partnerships and Projects.

Ships are invited to participate in the World Metereological Organization (WMO) Voluntary Observing Ships Scheme, to provide ship-based marine meteorological and oceanographic observations. Ships' meteorological observations are not only recognized as being essential for the provision of safety-related services for ships at sea, but also for ships' routeing, search and rescue, marine pollution prevention and climate change studies (i.e. quantifying extreme weather events that can affect the maritime industry). Additionally it has to be noted that sometimes ship-based meteorological and oceanographic reports are the only data available from data-sparse areas such as the polar regions.

Dumping of wastes at sea, carbon capture, ocean interventions for climate change mitigation

While MARPOL specifically targets accidental and operational discharges from ship operations, IMO also actively addresses marine pollution from land-based sources, albeit indirectly, through the London Dumping Convention and Protocol on the dumping of wastes and other matter at sea. The London Protocol, adopted in 1996, adopts a precautionary approach, prohibiting the discharge of wastes at sea except for a few on a permitted list, such as dredged material.

The London Convention/Protocol regime also contributes to climate change mitigation by regulating for carbon capture and sequestration in subsea geological formations and providing regulations and guidance on how to assess proposals for ocean fertilization and other marine ocean interventions for climate change mitigation.

Download infographic on 50 years of the London Convention here

Read more on actions under the London Convention and Protocol to address marine litter and other emerging issues here. 

Click on the image to read more about climate change mitigation technologies.


Partnerships for the oceans

Cooperation and collaboration for sustainable oceans and all ocean matters is essential.  

IMO is the secretariat for the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP), which is an inter-agency mechanism providing independent scientific advice to its ten sponsoring UN organizations. 

IMO is also playing an active role in other environmental cooperation mechanisms in the UN, such as UN-Oceans, the UN Environment Management Group ( UN EMG ), the Global Compact

IMO also works with other UN entities such as the Food and Agriculture Organization of the United Nations (FAO), including on fisheries related matters; the  International Seabed Authority (ISA); the Intergovernmental Oceanographic Commission of UNESCO (IOC-UNESCO); the United Nations Environment Programme (UNEP) and the United Nations Development Programme (UNDP) (see below).  

The Glo-X partnership projects

IMO, the United Nations Development Programme (UNDP) and the Global Environment Facility (GEF) have pioneered the “Glo-X model” of program design and implementation for marine environmental and energy efficiency

GEF-UNDP-IMO projects include:

  • Global Marine Plastic Litter Partnerships Project (GloLitter
  • Global Biofouling Project (GloFouling)
  • Global Ballast Water Management Project (GloBallast) - (completed)
  • Global Maritime Energy Efficiency Partnerships Project (GloMEEP) - (completed)

Read more about current IMO projects on the Partnerships and Projects pages. 


The United Nations Convention on the Law of the Sea was adopted in 1982. It lays down a comprehensive regime of law and order in the world's oceans and seas establishing rules governing all uses of the oceans and their resources. It embodies in one instrument traditional rules for the uses of the oceans and at the same time introduces new legal concepts and regimes and addresses new concerns. The Convention also provides the framework for further development of specific areas of the law of the sea.

Read more about IMO and UNCLOS and download Implications of UNCLOS for IMO.

IMO participates in the Intergovernmental Conference on an international legally binding instrument under the United Nations Convention on the Law of Sea on the conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction

Read more:

Maritime safety and security for sustainable use of the oceans

IMO regulations for the safety of shipping and for maritime security help support the sustainable use of the oceans. 

  • Read more about IMO’s maritime safety regulations here.
  • Read more about IMO’s work on maritime security here

Read more

  • Report: Ocean Stewardship 2030 - a roadmap for how ocean-related industries and policymakers jointly can secure a healthy and productive ocean by 2030. According to the report, transparency, cooperation and good standards will enable more sustainable food production, transport and energy production while dramatically improving ocean health. (United Nations Global Compact, June 2020)