IUCN 3 Oct 13;
An international panel of marine scientists, including IUCN experts, is demanding urgent remedies to halt ocean degradation based on findings that the rate, speed and impacts of change in the global ocean are greater, faster and more imminent than previously thought.
Results from the latest International Programme on the State of the Ocean (IPSO) / IUCN review of science on anthropogenic stressors on the ocean go beyond the conclusion reached last week by the UN climate change panel the IPCC that the ocean is absorbing much of the warming and unprecedented levels of carbon dioxide and warn that the cumulative impact of this with other ocean stressors is far graver than previous estimates.
Decreasing oxygen levels in the ocean caused by climate change and nitrogen run-off, combined with other chemical pollution and rampant overfishing are undermining the ability of the ocean to withstand these so-called ‘carbon perturbations’, meaning its role as Earth’s ‘buffer’ is seriously compromised.
Professor Alex Rogers of Somerville College, Oxford, and Scientific Director of IPSO said: “The health of the ocean is spiraling downwards far more rapidly than we had thought. We are seeing greater change, happening faster, and the effects are more imminent than previously anticipated. The situation should be of the gravest concern to everyone since everyone will be affected by changes in the ability of the ocean to support life on Earth.”
The findings, published in the peer review journal Marine Pollution Bulletin, are part of an ongoing assessment process overseen by IPSO, which brings together scientists from a range of marine disciplines. The body’s previous 2011 report, which warned of the threat of ‘globally significant’ extinctions of marine species, received global media attention and has been cited in hearings at the United Nations, US Senate and European Parliament as well as the UK Parliament.
IUCN’s Professor Dan Laffoley said: “What these latest reports make absolutely clear is that deferring action will increase costs in the future and lead to even greater, perhaps irreversible, losses. The UN climate report confirmed that the ocean is bearing the brunt of human-induced changes to our planet. These findings give us more cause for alarm – but also a roadmap for action. We must use it.”
Among the latest assessments of factors affecting ocean health, the panel identified the following areas as of greatest cause for concern:
• De-oxygenation: the evidence is accumulating that the oxygen inventory of the ocean is progressively declining. Predictions for ocean oxygen content suggest a decline of between 1% and 7% by 2100. This is occurring in two ways: the broad trend of decreasing oxygen levels in tropical oceans and areas of the North Pacific over the last 50 years; and the dramatic increase in coastal hypoxia (low oxygen) associated with eutrophication. The former is caused by global warming, the second by increased nutrient runoff from agriculture and sewage.
• Acidification: If current levels of CO2 release continue we can expect extremely serious consequences for ocean life, and in turn food and coastal protection; at CO2 concentrations of 450-500 ppm (projected in 2030-2050) erosion will exceed calcification in the coral reef building process, resulting in the extinction of some species and decline in biodiversity overall.
• Warming: As made clear by the IPCC, the ocean is taking the brunt of warming in the climate system, with direct and well-documented physical and biogeochemical consequences. The impacts which continued warming is projected to have in the decades to 2050 include: reduced seasonal ice zones, including the disappearance of Arctic summer sea ice by ca. 2037; increasing stratification of ocean layers, leading to oxygen depletion; increased venting of the GHG methane from the Arctic seabed (a factor not considered by the IPCC); and increased incidence of anoxic and hypoxic (low oxygen) events.
• The ‘deadly trio’ of the above three stressors - acidification, warming and deoxygenation - is seriously effecting how productive and efficient the ocean is, as temperatures, chemistry, surface stratification, nutrient and oxygen supply are all implicated, meaning that many organisms will find themselves in unsuitable environments. These impacts will have cascading consequences for marine biology, including altered food web dynamics and the expansion of pathogens.
• Continued overfishing is serving to further undermine the resilience of ocean systems, and contrary to some claims, despite some improvements largely in developed regions, fisheries management is still failing to halt the decline of key species and damage to the ecosystems on which marine life depends. In 2012 the UN FAO determined that 70% of world fish populations are unsustainably exploited, of which 30% have biomass collapsed to less than 10% of unfished levels. A recent global assessment of compliance with Article 7 (fishery management) of the 1995 FAO Code of Conduct for Responsible Fisheries, awarded 60% of countries a “fail” grade, and saw no country identified as being overall “good”.
As a matter of urgency, the marine scientists say that world governments must:
• Reduce global C02 emissions to limit temperature rise to less than 2oC, or below 450 CO2e. Current targets for carbon emission reductions are insufficient in terms of ensuring coral reef survival and other biological effects of acidification, especially as there is a time lag of several decades between atmospheric CO2 and CO2 dissolved in the ocean. Potential knock-on effects of climate change in the ocean, such as methane release from melting permafrost, and coral dieback, mean the consequences for human and ocean life could be even worse than presently calculated.
• Ensure effective implementation of community- and ecosystem-based management, favouring small-scale fisheries. 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 combating IUU fishing.
• Build a global infrastructure for high seas governance that is fit-for-purpose. Most importantly, secure a new implementing agreement for the conservation and sustainable use of biodiversity in areas beyond national jurisdiction under the auspices of UNCLOS.
Notes for Editors:
The report’s lead authors:
Alex Rogers is Professor of Conservation Biology at the Department of Zoology, University of Oxford and a Fellow of Somerville College. He is a marine biologist with special expertise on deep-sea ecosystems, particularly cold-water coral habitats, seamounts and hydrothermal vents and has recently led scientific expeditions to the Indian and Southern Oceans. He also has a special interest in sustainable use of the oceans and human impacts on marine ecosystem. Alex is also Scientific Director of the International Programme on State of the Ocean, an NGO that is specifically analysing current impacts on marine ecosystems globally (see below).
Professor Dan Laffoley, IUCN Vice-chair, World Commission on Protected Areas is a key figure at the global scale on marine conservation, and widely recognized for his leadership on Marine Protected Areas and innovative conservation approaches. For over 25 years he has been involved in leading marine protection efforts at UK, European and global scales creating many of the key initiatives and concepts that underlie our modern approaches to protecting the ocean.
The organisations:
IPSO: The International Programme on the State of the Ocean is a unique consortium of scientists and other Ocean experts, including those from the legal, communications and political arenas, created to identify the current problems affecting the global ocean, project the future outcomes of these problems and develop workable solutions to alter the trajectory of degradation. www.stateoftheocean.org
IUCN: The International Union for Conservation of Nature is a global environmental network with more than 1,000 government and NGO member organizations, and almost 11,000 volunteer scientists in more than 160 countries. www.iucn.org
The Report:
The findings were published in Marine Pollution Bulletin Volume 74 Issue 2 and available at http://www.sciencedirect.com/science/journal/0025326X/74 and also at http://www.stateoftheocean.org
Health of oceans 'declining fast'
Roger Harrabin BBC News 3 Oct 13;
The health of the world’s oceans is deteriorating even faster than had previously been thought, a report says.
A review from the International Programme on the State of the Ocean (IPSO), warns that the oceans are facing multiple threats.
They are being heated by climate change, turned slowly less alkaline by absorbing CO2, and suffering from overfishing and pollution.
The report warns that dead zones formed by fertiliser run-off are a problem.
It says conditions are ripe for the sort of mass extinction event that has afflicted the oceans in the past.
It says: “We have been taking the ocean for granted. It has been shielding us from the worst effects of accelerating climate change by absorbing excess CO2 from the atmosphere.
“Whilst terrestrial temperature increases may be experiencing a pause, the ocean continues to warm regardless. For the most part, however, the public and policymakers are failing to recognise - or choosing to ignore - the severity of the situation.”
It says the cocktail of threats facing the ocean is more powerful than the individual problems themselves.
Coral reefs, for instance, are suffering from the higher temperatures and the effects of acidification whilst also being weakened by bad fishing practices, pollution, siltation and toxic algal blooms.
Atmospheric threshold
IPSO, funded by charitable foundations, is publishing a set of five papers based on workshops in 2011 and 2012 in partnership with the International Union for Conservation of Nature (IUCN’s) World Commission on Protected Areas.
The reports call for world governments to halt CO2 increase at 450ppm. Any higher, they say, will cause massive acidification later in the century as the CO2 is absorbed into the sea.
It urges much more focused fisheries management, and a priority list for tackling the key groups of chemicals that cause most harm.
It wants the governments to negotiate a new agreement for the sustainable fishing in the high oceans to be policed by a new global high seas enforcement agency.
The IUCN’s Prof Dan Laffoley said: "What these latest reports make absolutely clear is that deferring action will increase costs in the future and lead to even greater, perhaps irreversible, losses.
"The UN climate report confirmed that the ocean is bearing the brunt of human-induced changes to our planet. These findings give us more cause for alarm – but also a roadmap for action. We must use it."
'Extinction risk'
The co-coordinator, Prof Alex Rogers from Oxford University has been asked to advise the UN's own oceans assessment but he told BBC News he had led the IPSO initiative because: "It’s important to have something which is completely independent in any way from state influence and to say things which experts in the field felt was really needed to be said."
He said concern had grown over the past year thanks to papers signalling that past extinctions had involved warming seas, acidification and low oxygen levels. All are on the rise today.
He agreed there was debate on whether fisheries are recovering by better management following examples in the US and Europe, but said it seemed clear that globally they were not.
He also admitted a debate about whether overall climate change would increase the amount of fish produced in the sea. Melting sea ice would increase fisheries near the poles whilst stratification of warmer waters in the tropics would reduce mixing of nutrients and lead to lower production, he said.
He said dead zones globally appeared to be increasing although this may reflect increased reporting.
"On ocean acidification, we are seeing effects that no-one predicted like the inability of fish to detect their environments properly. It’s clear that it will affect many species. We really do have to get a grip on what’s going on in the oceans," he said.
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
Fiona Harvey The Guardian 3 Oct 13;
The oceans are more acidic now than they have been for at least 300m years, due to carbon dioxide emissions from burning fossil fuels, and a mass extinction of key species may already be almost inevitable as a result, leading marine scientists warned on Thursday.
An international audit of the health of the oceans has found that overfishing and pollution are also contributing to the crisis, in a deadly combination of destructive forces that are imperilling marine life, on which billions of people depend for their nutrition and livelihood.
In the starkest warning yet of the threat to ocean health, the International Programme on the State of the Ocean (IPSO) said: "This [acidification] is unprecedented in the Earth's known history. We are entering an unknown territory of marine ecosystem change, and exposing organisms to intolerable evolutionary pressure. The next mass extinction may have already begun." It published its findings in the State of the Oceans report, collated every two years from global monitoring and other research studies.
Alex Rogers, professor of biology at Oxford University, said: "The health of the ocean is spiralling downwards far more rapidly than we had thought. We are seeing greater change, happening faster, and the effects are more imminent than previously anticipated. The situation should be of the gravest concern to everyone since everyone will be affected by changes in the ability of the ocean to support life on Earth."
Coral is particularly at risk. Increased acidity dissolves the calcium carbonate skeletons that form the structure of reefs, and increasing temperatures lead to bleaching where the corals lose symbiotic algae they rely on. The report says that world governments' current pledges to curb carbon emissions would not go far enough or fast enough to save many of the world's reefs. There is a time lag of several decades between the carbon being emitted and the effects on seas, meaning that further acidification and further warming of the oceans are inevitable, even if we drastically reduce emissions very quickly. There is as yet little sign of that, with global greenhouse gas output still rising.
Corals are vital to the health of fisheries, because they act as nurseries to young fish and smaller species that provide food for bigger ones.
Carbon dioxide in the atmosphere is absorbed by the seas – at least a third of the carbon that humans have released has been dissolved in this way, according to the Intergovernmental Panel on Climate Change – and makes them more acidic. But IPSO found the situation was even more dire than that laid out by the world's top climate scientists in their landmark report last week.
In absorbing carbon and heat from the atmosphere, the world's oceans have shielded humans from the worst effects of global warming, the marine scientists said. This has slowed the rate of climate change on land, but its profound effects on marine life are only now being understood.
Acidification harms marine creatures that rely on calcium carbonate to build coral reefs and shells, as well as plankton, and the fish that rely on them. Jane Lubchenco, former director of the US National Oceanic and Atmospheric Administration and a marine biologist, said the effects were already being felt in some oyster fisheries, where young larvae were failing to develop properly in areas where the acid rates are higher, such as on the west coast of the US. "You can actually see this happening," she said. "It's not something a long way into the future. It is a very big problem."
But the chemical changes in the ocean go further, said Rogers. Marine animals use chemical signals to perceive their environment and locate prey and predators, and there is evidence that their ability to do so is being impaired in some species.
Trevor Manuel, a South African government minister and co-chair of the Global Ocean Commission, called the report "a deafening alarm bell on humanity's wider impacts on the global oceans".
"Unless we restore the ocean's health, we will experience the consequences on prosperity, wellbeing and development. Governments must respond as urgently as they do to national security threats – in the long run, the impacts are just as important," he said.
Current rates of carbon release into the oceans are 10 times faster than those before the last major species extinction, which was the Paleocene-Eocene Thermal Maximum extinction, about 55m years ago. The IPSO scientists can tell that the current ocean acidification is the highest for 300m years from geological records.
They called for strong action by governments to limit carbon concentrations in the atmosphere to no more than 450 parts per million of carbon dioxide equivalent. That would require urgent and deep reductions in fossil fuel use.
No country in the world is properly tackling overfishing, the report found, and almost two thirds are failing badly. At least 70 per cent of the world's fish populations are over-exploited. Giving local communities more control over their fisheries, and favouring small-scale operators over large commercial vessels would help this, the report found. Subsidies that drive overcapacity in fishing fleets should also be eliminated, marine conservation zones set up and destructive fishing equipment should be banned. There should also be better governance of the areas of ocean beyond countries' national limits.
The IPSO report also found the oceans were being "deoxygenated" – their average oxygen content is likely to fall by as much as 7 per cent by 2100, partly because of the run-off of fertilisers and sewage into the seas, and also as a side-effect of global warming. The reduction of oxygen is a concern as areas of severe depletion become effectively dead.
Rogers said: "People are just not aware of the massive roles that the oceans play in the Earth's systems. Phytoplankton produce 40 per cent of the oxygen in the atmosphere, for example, and 90 per cent of all life is in the oceans. Because the oceans are so vast, there are still areas we have never really seen. We have a very poor grasp of some of the biochemical processes in the world's biggest ecosystem."
The five chapters of which the State of the Oceans report is a summary have been published in the Marine Pollution Bulletin, a peer-reviewed journal.
Oceans face 'deadly trio' of threats, study says
Alister Doyle, Reuters, 3 Oct 13;
(Reuters) - The world's oceans are under greater threat than previously believed from a "deadly trio" of global warming, declining oxygen levels and acidification, an international study said on Thursday.
The oceans have continued to warm, pushing many commercial fish stocks towards the poles and raising the risk of extinction for some marine species, despite a slower pace of temperature rises in the atmosphere this century, it said.
"Risks to the ocean and the ecosystems it supports have been significantly underestimated," according to the International Programme on the State of the Ocean (IPSO), a non-governmental group of leading scientists.
"The scale and rate of the present day carbon perturbation, and resulting ocean acidification, is unprecedented in Earth's known history," according to the report, made with the International Union for Conservation of Nature.
The oceans are warming because of heat from a build-up of greenhouse gases in the atmosphere. Fertilizers and sewage that wash into the oceans can cause blooms of algae that reduce oxygen levels in the waters. And carbon dioxide in the air can form a weak acid when it reacts with sea water.
"The ‘deadly trio' of ... acidification, warming and deoxygenation is seriously affecting how productive and efficient the ocean is," the study said.
Alex Rogers of Oxford University, scientific director of IPSO, told Reuters scientists were finding that threats to the oceans, from the impacts of carbon to over-fishing, were compounding one another.
"We are seeing impacts throughout the world," he said.
EXTINCTIONS
Current conditions in the oceans were similar to those 55 million years ago, known as the Paleocene-Eocene thermal maximum, that led to wide extinctions. And the current pace of change was much faster and meant greater stresses, Rogers said.
Acidification, for instance, threatens marine organisms that use calcium carbonate to build their skeletons - such as reef-forming corals, crabs, oysters and some plankton vital to marine food webs.
Corals might cease to grow if temperatures rose by 2 degrees Celsius (3.6F) and start to dissolve at 3 degrees (5.4F), the study said.
Scientists said the findings added urgency to a plan by almost 200 governments to work out a deal by the end of 2015 to limit a rise in average world temperatures to less than 2 degrees Celsius (3.6F) above pre-industrial times.
Temperatures have already risen by about 0.8 degree Celsius (1.4F). The report also urged tougher management of fish stocks including a ban on destructive bottom trawlers and granting more power to local communities in developing nations to set quotas.
Last week, a report by the U.N.'s Intergovernmental Panel on Climate Change (IPCC) raised the probability that mankind was the culprit for most global warming to 95 percent, from 90 in a report in 2007.
The Global Ocean Commission, a group of politicians working to advise governments, urged stronger action.
"If the IPCC report was a wake-up call on climate change, IPSO is a deafening alarm bell on humanity's wider impacts on the global ocean," said Trevor Manuel, co-chair of the Commission and minister in the South African Presidency.
(Reporting By Alister Doyle, editing by Elizabeth Piper)
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