The State of the Ocean report 2013


On 30 September 2013, IPSO published the ‘State of the Ocean Report 2013’ in the Marine Pollution Bulletin, which comprised a set of five papers on ocean stresses, impacts and solutions. These papers were produced by leading international experts to present the key findings of IPSO’s State of the Ocean workshops.

State of the Ocean 2013 report

  • Edited by Alex D. Rogers


Introduction to the Special Issue: The Global State of the Ocean; Interactions Between Stresses, Impacts and Some Potential Solutions. Synthesis papers from the International Programme on the State of the Ocean 2011 and 2012 Workshops. Marine Pollution Bulletin. 74: Issue 2, 491–552; 30 Sept 2013.

Key findings

Through presentations, discussion and debate, participants in the two State of the Ocean workshops concluded that not only are we already experiencing severe declines in many species, to the point of commercial extinction in some cases, and an unparalleled rate of regional extinctions of habitat types (e.g. mangroves and seagrass meadows), but we now face losing marine species and entire marine ecosystems, such as coral reefs, within a single generation. Unless action is taken now, the consequences of our activities are at a high risk of causing – through the combined effects of climate change, overexploitation, pollution and habitat loss – the next globally significant extinction event in the ocean. It is notable that the occurrence of multiple high-intensity stressors has been a pre-requisite for all the five global extinction events of the past 600 million years (Barnosky et al., 2009).

The key points underlying this conclusion are:

Human actions have resulted in warming and acidification of the oceans and are now causing increased hypoxia

Studies of the Earth’s past indicate that warming, acidification and hypoxia are three symptoms that indicate disturbances of the carbon cycle associated with each of the previous five mass extinctions on Earth.

The speeds of many negative changes to the ocean are near to or are tracking the worst-case scenarios from IPCC and other predictions. Some are as predicted, but many are faster than anticipated, and many are still accelerating

Consequences of current rates of change already matching those predicted under the ‘worst case scenario’ include: the rate of decrease in Arctic Sea Ice and in the accelerated melting of the Greenland ice sheet and the Antarctic ice sheets; sea level rise; release of trapped methane from the seabed. These ‘worst case’ effects are compounding other changes more consistent with predictions, for example: changes in the distribution and abundance of marine species; changes in primary production; changes in the distribution of harmful algal blooms; increases in health hazards in the oceans; loss of large, long-lived fish species causing the simplification and destabilisation of food webs in marine ecosystems.

The magnitude of the cumulative impacts on the ocean is greater than previously understood

Interactions between different impacts can be negatively synergistic (negative impact greater than sum of individual stressors) or they can be antagonistic (lowering the effects of individual impacts).

Examples of such interactions include:

  • combinations of overfishing, physical disturbance, climate explosions of these invasive species – including harmful algal blooms – and dead zones;
  • increased temperature and acidification increasing the susceptibility of corals to bleaching and to acting synergistically to impact the reproduction and development of other marine invertebrates;
  • changes in the behaviour, fate and toxicity of heavy metals with acidification – acidification may reduce the limiting effect of iron availability on primary production in some parts of the ocean;
  • increased uptake of plastics by fauna, and increased bioavailability of pollutants through adsorption onto the surface of microplastic particles;
  • feedbacks of climate change impacts on the oceans (temperature rise, sea level rise, loss of ice cover, acidification, increased storm intensity, methane release) on their rate of carbon dioxide uptake and global warming.

Timelines for action are shrinking

The longer the delay in reducing emissions the higher the annual reduction rate will have to be and the greater the financial cost. Delays will mean increased environmental damage with greater socioeconomic impacts and costs of mitigation and adaptation measures.

Resilience of the ocean to climate change impacts is severely compromised by the other stressors from human activities, including fisheries, pollution and habitat destruction

Examples include the overfishing of reef grazers, nutrient runoff, and other forms of pollution (e.g. presence of pathogens or endocrine disrupting chemicals) reducing the ability of reefs to recover from temperature-induced mass coral bleaching. These multiple stressors promote the phase-shift of reef ecosystems from being coral-dominated to algal-dominated. The loss of genetic diversity from overfishing reduces the ocean’s ability to adapt to stressors.

Ecosystem collapse is occurring as a result of both current and emerging stressors

Stressors include chemical pollutants, agriculture run-off, sediment loads and over-extraction of many components of food webs, which singly and together severely impair the functioning of ecosystems. Consequences include: the potential increase of harmful algal blooms in recent decades; the spread of oxygen-depleted or dead zones; the disturbance of the structure and functioning of marine food webs, to the benefit of planktonic organisms of low nutritional value such as jellyfish or other gelatinous-like organisms; dramatic changes in the microbial communities, with negative impacts at the ecosystem scale; the impact of emerging chemical contaminants in ecosystems.

This impairment damages or eliminates the ability of ecosystems to support humans.

The extinction threat to marine species is increasing rapidly

The main causes of extinctions of marine species to date are over-exploitation and habitat loss. However, climate change is an increasing threat to species, as evidenced by the recent IUCN Red List Assessment of reef-forming corals. Some other species ranges have already extended or shifted polewards and into deeper cooler waters, though this may not be possible for some species to achieve, potentially leading to reduced habitats and more extinctions. Shifts in currents and temperatures will affect the food supply of animals, including at critical early stages, potentially testing their ability to survive.


The technical means to achieve the solutions to many of the problems that the two State of the Ocean workshops identified already exist. However, current societal values prevent humankind from addressing them effectively. Overcoming these barriers is core to the fundamental changes needed to achieve a sustainable and equitable future for the generations to come through preserving the natural ecosystems of the Earth that we benefit from and enjoy today.

Participants recommended actions in four areas.

Immediate reduction in carbon dioxide emissions

These reductions should be coupled with significantly increased measures for mitigation of atmospheric CO2 and to better manage coastal and marine carbon sinks to avoid additional emissions of greenhouse gases. It is a matter of urgency that the ocean is considered a priority in the deliberations of the IPCC and UNFCCC.

Urgent actions to restore the structure and function of marine ecosystems

These should include the coordinated and concerted action in national waters and on the High Seas (the high seas water column and seabed Area beyond national jurisdiction) by states and regional bodies to:

  • reduce fishing effort to levels commensurate with long-term sustainability of fisheries and the marine environment;
  • close fisheries that are not demonstrably managed following sustainable principles, or which depend wholly on government subsidies;
  • establish a globally comprehensive and representative system of marine protected areas to conserve biodiversity, to build resilience, and to ensure ecologically sustainable fisheries with minimal ecological footprint;
  • prevent, reduce and strictly control inputs of substances that are harmful or toxic to marine organisms into the marine environment;
  • prevent, reduce and strictly control nutrient inputs into the marine environment through better land and river catchment management and sewage treatment;
  • avoid, reduce or, at minimum, universally and stringently regulate oil, gas, aggregate and mineral extraction;
  • assess, monitor and control other uses of the marine environment such as renewable energy schemes or cable / pipeline installation through comprehensive spatial planning and impact assessments procedures.

Proper and universal implementation of the precautionary principle

This can be done by reversing the burden of proof so activities proceed only if they are shown not to harm the ocean singly or in combination with other activities.

Urgent introduction by the UN Security Council and the UN General Assembly of effective governance of the High Seas beyond the jurisdiction of any individual nations

This should include a global body empowered to ensure compliance with the UN Convention on the Law of the Sea and other relevant legal duties and norms and to establish new rules, regulations and procedures where necessary to implement these requirements in an ecosystem-based and precautionary manner.

Five papers: Summaries

The State of the Ocean Report 2013 comprises five synthesis papers. These papers aim to contribute to actions to address the problems we now face by analysing the effects of and links between the ocean’s major stressors, as well as identifying the best available options for addressing them effectively.

Paper 1

Climate change and the ocean: What does the future hold?

The ocean is shielding us from the worst effects of accelerating climate change by absorbing excess CO2 and heat from the atmosphere. The twin effects of this – acidification and ocean warming – are combining with increased levels of deoxygenation caused by nutrient run-off from agriculture near the coast and climate change offshore to produce what has become known as the ocean’s ‘deadly trio’ of threats, whose impacts are potentially far greater because of the interaction of one with another. The scale and rate of this change is unprecedented in the Earth’s known history and is exposing organisms to intolerable and unpredictable evolutionary pressure.

Paper 2

Fisheries: Hope or despair?

The global picture of ongoing depletions of fish stocks, the degradation of food webs, threats to seafood security and poor quality of most fishing management is alarming and demonstrates that recent more optimistic outlooks are misplaced. Reversing these global trends towards “despair” demands urgent, focused, innovative action to promote effective community- and ecosystem-based management.

Paper 3

Evaluating legacy contaminants and emerging chemicals in marine environments

Protecting marine ecosystems and seafood resources from the adverse effects of complex cocktails of ‘legacy’ (already regulated) contaminants, emerging (unregulated) chemicals and natural chemicals (e.g. algal biotoxins) remains a critical, unresolved global problem. The economic and infrastructural challenges posed by such a wide variety of chemicals means that the most cost-effective approach is to implement a targeted, effects-based strategy that prioritises key groups of chemicals of most concern.

Paper 4

Climate change impacts on coral reefs: Synergies with local effects, possibilities for acclimation, and management implications

Coral reefs are extremely vulnerable to the impacts of climate change. It is imperative and urgent that emissions targets below 450 ppm CO2e be agreed and implemented, combined with coordinated programmes at local and regional levels to reduce other stress factors and boost resilience; otherwise it is predicted that most reefs will be lost as effective, productive systems within a few decades.

Paper 5

Ocean in peril: Reforming the management of global ocean living resources in areas beyond national jurisdiction

The current system of high seas governance is fraught with gaps, directly leading to the mismanagement and misappropriation of living resources, and placing our ocean in peril. It is time for a new paradigm that can only come about through the fundamental reform of existing organisations and systems, overseen by a new global infrastructure to coordinate and enforce the necessary action. Crucially, the authors call for the negotiation of a new implementing agreement for the conservation and sustainable use of biodiversity in areas beyond national jurisdiction.