State of the Ocean: Ocean Acidification and Previous Marine Extinctions
â˘ Climate change and the ocean â What does the future hold?
The ocean isshielding us from the worst effects of accelerating climate change by absorbing excess CO2 and heat from the atmosphere. The twin effects of this â acidification and ocean warming â are combining with increased levels of deoxygenation, caused by nutrient run-off from agriculture near the coast ,and by climate change offshore, to produce what has become known as the oceanâs âdeadly trioâ of threats whose impacts are potentially far greater because of the interaction of one on another. The scale and rate of this change is unprecedented in Earthâs known history and is exposing organisms to intolerable and unpredictable evolutionary pressure.
â˘ Climate change impacts on coral reefs
Synergies with local effects, possibilities for acclimation, and management implicationsÂ 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.
â˘ 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 aremisplaced. Reversing these global trends towards âdespairâ demands urgent, focused, innovative action to promote effective community- and ecosystem-based management.
â˘ Evaluating legacy contaminants and emerging chemicals in marine environments.
Protecting marine ecosystems and seafood resources from the adverse effects of complex cocktails of âlegacyâ (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 prioritizes key groups of chemicals of most concern.
â˘ 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 themismanagement 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.
Founded to investigate the impacts of anthropogenic stressors on the ocean and identify workable solutions to eliminate or remedy them, IPSOâ with the support of IUCN â is unique in bringing together experts from a range of disciplines within marine science, as well as the legal, policy and communications arenas, in order to highlight the connectivity and synergy between the multiple stressors impacting the ocean and treat them collectively.
This holistic approach is essential to developing viable, practical solutions that consider marine ecosystem health, socio-economic drivers, as well as the larger Earth system perspective. Achieving this integrated, ecosystem-based management of the ocean and its resources is an immensely complex challenge but these five papers all stress that we have a vast wealth of information, expertise, management tools and proven solutions at our disposal.
The two IPSO workshops showed that deferring action will increase costs in the future and lead to even greater, perhaps irreversible, losses. If we want to continue to benefit from the goods and services the ocean has provided for millennia, we must radically change the way we view, value, use and govern marine ecosystems
As a matter of urgency, IPSO urges that:
â˘ There should be a significant reduction in global C02 emissions to limit temperature rise to less than 2C or below 450 CO2e . Current targets for carbon emission reductions are insufficient in terms of ensuring coral reef survival, especially as there is a time lag of several decades between atmospheric CO2 and CO2Â dissolved in the ocĂŠan.
â˘ Effective implementation of community – and ecosystem-based management, favouring small-scale fisheries is achieved. Examples of broad-scale measures include introducing true co-management with resource adjacent communities, eliminating harmful subsidies that drive overcapacity, protection of vulnerable marine ecosystems, banning the most destructive fishing gear and combatting IUU fishing.
â˘ The global infrastructure for high seas governance should be enhanced so that it is fit-for-purpose. A global high seas enforcement agency should be established to provide integrated and coordinated monitoring and enforcement for the full range of threats to ocean sustainability and globalsecurity. Most importantly, a new implementing agreement for the conservation and sustainable use of biodiversity in areas beyond national jurisdiction under the auspices of UNCLOS should be introduced urgently.
Ocean acidification due to carbon emissions is at highest for 300m years
Overfishing and pollution are part of the problem, scientists say, warning that mass extinction of species may be inevitable
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Image rights: NOAA Â http://www.flickr.com/photos/oceanexplorergov/9267769511/