Marlowe Hood Yahoo News 20 Jun 11;
PARIS (AFP) – Pollution and global warming are pushing the world's oceans to the brink of a mass extinction of marine life unseen for tens of millions of years, a consortium of scientists warned Monday.
Dying coral reefs, biodiversity ravaged by invasive species, expanding open-water "dead zones," toxic algae blooms, the massive depletion of big fish stocks -- all are accelerating, they said in a report compiled during an April meeting in Oxford of 27 of the world's top ocean experts.
Sponsored by the International Programme on the State of the Ocean (IPSO), the review of recent science found that ocean health has declined further and faster than dire forecasts only a few years ago.
These symptoms, moreover, could be the harbinger of wider disruptions in the interlocking web of biological and chemical interactions that scientists now call the Earth system.
All five mass extinctions of life on the planet, reaching back more than 500 million years, were preceded by many of the same conditions now afflicted the ocean environment, they said.
"The results are shocking," said Alex Rogers, an Oxford professor who heads IPSO and co-authored the report. "We are looking at consequences for humankind that will impact in our lifetime."
Three main drivers are sickening the global marine environment, and all are a direct consequence of humans activity: global warming, acidification and a dwindling level oxygen, a condition known as hypoxia.
Up to now, these and other impacts have been studied mainly in isolation. Only recently have scientists began to understand how these forces interact.
"We have underestimated the overall risks, and that the whole of marine degradation is greater than the sum of its parts," Rogers said. "That degradation is now happening at a faster rate than predicted."
Indeed, the pace of change is tracking or has surpassed the worst-case scenarios laid out by the UN Intergovernmental Panel on Climate Change (IPCC) in its landmark 2007 report, according to the new assessment.
The chain reaction leading to increased acidification of the oceans begins with a massive influx of carbon into Earth's climate system.
Oceans act as a massive sponge, soaking up more than a quarter of the CO2 humans pump into the atmosphere.
But when the sponge becomes too saturated, it can disrupt the delicately balanced ecosystems on which marine life -- and ultimately all life on Earth -- depends.
"The rate at which carbon is being absorbed is already far greater now than during the last globally significant extinction of marine species 55 million years ago," when some 50 percent of deep-sea life was wiped out, the report said.
That event, called the Paleocene-Eocene Thermal Maximum, or PETM, may be an ancient dress rehearsal for future climate change that could be even more abrupt and more damaging, some scientists fear.
Pollution has also taken a heavy toll, rendering the oceans less resilient to climate change.
Runoff from nitrogen-rich fertiliser, killer microbes, and hormone-disrupting chemicals, for example, have all contributed to the mass die-off of corals, crucial not just for marine ecosystems but a lifeline for hundreds of millions of people too.
The harvesting up to 90 percent of some species of big fish and sharks, meanwhile, has hugely disrupted food chains throughout the ocean, leading to explosive and imbalanced growth of algae, jellyfish and other "opportunistic" flora and fauna.
"We now face losing marine species and entire marine ecosystems, such as coral reefs, within a single generation," said Daniel Laffoley, head of the International Union for Conservation of Nature's (IUCN) World Commission on Protected Areas, and co-author of the report.
"And we are also probably the last generation that has enough time to deal with the problems," he told AFP by phone.
Ocean life on the brink of mass extinctions: study
Reuters 21 Jun 11;
(Reuters) - Life in the oceans is at imminent risk of the worst spate of extinctions in millions of years due to threats such as climate change and over-fishing, a study showed on Tuesday.
Time was running short to counter hazards such as a collapse of coral reefs or a spread of low-oxygen "dead zones," according to the study led by the International Programme on the State of the Ocean (IPSO).
"We now face losing marine species and entire marine ecosystems, such as coral reefs, within a single generation," according to the study by 27 experts to be presented to the United Nations.
"Unless action is taken now, the consequences of our activities are at a high risk of causing, through the combined effects of climate change, over-exploitation, pollution and habitat loss, the next globally significant extinction event in the ocean," it said.
Scientists list five mass extinctions over 600 million years -- most recently when the dinosaurs vanished 65 million years ago, apparently after an asteroid struck. Among others, the Permian period abruptly ended 250 million years ago.
"The findings are shocking," Alex Rogers, scientific director of IPSO, wrote of the conclusions from a 2011 workshop of ocean experts staged by IPSO and the International Union for Conservation of Nature (IUCN) at Oxford University.
Fish are the main source of protein for a fifth of the world's population and the seas cycle oxygen and help absorb carbon dioxide, the main greenhouse gas from human activities.
OXYGEN
Jelle Bijma, of the Alfred Wegener Institute, said the seas faced a "deadly trio" of threats of higher temperatures, acidification and lack of oxygen, known as anoxia, that had featured in several past mass extinctions.
A build-up of carbon dioxide, blamed by the U.N. panel of climate scientists on human use of fossil fuels, is heating the planet. Absorbed into the oceans, it causes acidification, while run-off of fertilizers and pollution stokes anoxia.
"From a geological point of view, mass extinctions happen overnight, but on human timescales we may not realize that we are in the middle of such an event," Bijma wrote.
The study said that over-fishing is the easiest for governments to reverse -- countering global warming means a shift from fossil fuels, for instance, toward cleaner energies such as wind and solar power.
"Unlike climate change, it can be directly, immediately and effectively tackled by policy change," said William Cheung of the University of East Anglia.
"Over-fishing is now estimated to account for over 60 percent of the known local and global extinction of marine fishes," he wrote.
Among examples of over-fishing are the Chinese bahaba that can grow 2 meters long. Prices per kilo (2.2 lbs) for its swim bladder -- meant to have medicinal properties -- have risen from a few dollars in the 1930s to $20,000-$70,000.
(Editing by Jan Harvey)
World's oceans in 'shocking' decline
Richard Black BBC News 20 Jun 11;
The oceans are in a worse state than previously suspected, according to an expert panel of scientists.
In a new report, they warn that ocean life is "at high risk of entering a phase of extinction of marine species unprecedented in human history".
They conclude that issues such as over-fishing, pollution and climate change are acting together in ways that have not previously been recognised.
The impacts, they say, are already affecting humanity.
The panel was convened by the International Programme on the State of the Ocean (IPSO), and brought together experts from different disciplines, including coral reef ecologists, toxicologists, and fisheries scientists.
Its report will be formally released later this week.
"The findings are shocking," said Alex Rogers, IPSO's scientific director and professor of conservation biology at Oxford University.
"As we considered the cumulative effect of what humankind does to the oceans, the implications became far worse than we had individually realised.
"We've sat in one forum and spoken to each other about what we're seeing, and we've ended up with a picture showing that almost right across the board we're seeing changes that are happening faster than we'd thought, or in ways that we didn't expect to see for hundreds of years."
These "accelerated" changes include melting of the Greenland and Antarctic ice sheets, sea level rise, and release of methane trapped in the sea bed.
Fast changes
"The rate of change is vastly exceeding what we were expecting even a couple of years ago," said Ove Hoegh-Guldberg, a coral specialist from the University of Queensland in Australia.
"So if you look at almost everything, whether it's fisheries in temperate zones or coral reefs or Arctic sea ice, all of this is undergoing changes, but at a much faster rate than we had thought."
But more worrying than this, the team noted, are the ways in which different issues act synergistically to increase threats to marine life.
Some pollutants, for example, stick to the surfaces of tiny plastic particles that are now found in the ocean bed.
This increases the amounts of these pollutants that are consumed by bottom-feeding fish.
Plastic particles also assist the transport of algae from place to place, increasing the occurrence of toxic algal blooms - which are also caused by the influx of nutrient-rich pollution from agricultural land.
In a wider sense, ocean acidification, warming, local pollution and overfishing are acting together to increase the threat to coral reefs - so much so that three-quarters of the world's reefs are at risk of severe decline.
Carbon deposits
Life on Earth has gone through five "mass extinction events" caused by events such as asteroid impacts; and it is often said that humanity's combined impact is causing a sixth such event.
The IPSO report concludes that it is too early to say definitively.
But the trends are such that it is likely to happen, they say - and far faster than any of the previous five.
"What we're seeing at the moment is unprecedented in the fossil record - the environmental changes are much more rapid," Professor Rogers told BBC News.
"We've still got most of the world's biodiversity, but the actual rate of extinction is much higher [than in past events] - and what we face is certainly a globally significant extinction event."
The report also notes that previous mass extinction events have been associated with trends being observed now - disturbances of the carbon cycle, and acidification and hypoxia (depletion of oxygen) of seawater.
Levels of CO2 being absorbed by the oceans are already far greater than during the great extinction of marine species 55 million years ago (during the Paleocene-Eocene Thermal Maximum), it concludes.
Blue planet
The report's conclusions will be presented at UN headquarters in New York this week, when government delegates begin discussions on reforming governance of the oceans.
IPSO's immediate recommendations include:
stopping exploitative fishing now, with special emphasis on the high seas where currently there is little effective regulation
mapping and then reducing the input of pollutants including plastics, agricultural fertilisers and human waste
making sharp reductions in greenhouse gas emissions.
Carbon dioxide levels are now so high, it says, that ways of pulling the gas out of the atmosphere need to be researched urgently - but not using techniques, such as iron fertilisation, that lead to more CO2 entering the oceans.
"We have to bring down CO2 emissions to zero within about 20 years," Professor Hoegh-Guldberg told BBC News.
"If we don't do that, we're going to see steady acidification of the seas, heat events that are wiping out things like kelp forests and coral reefs, and we'll see a very different ocean."
Another of the report's authors, Dan Laffoley, marine chair of the World Commission on Protected Areas and an adviser to the International Union for the Conservation of Nature (IUCN), admitted the challenges were vast.
"But unlike previous generations, we know what now needs to happen," he said.
"The time to protect the blue heart of our planet is now."
Multiple ocean stresses threaten “globally significant” marine extinction
IUCN 20 Jun 11;
An international panel of experts warns in a report released today that marine species are at risk of entering a phase of extinction unprecedented in human history.
The preliminary report arises from a ‘State of the Oceans’ workshop co-hosted by IUCN in April, the first ever to consider the cumulative impact of all pressures on the oceans. Considering the latest research across all areas of marine science, the workshop examined the combined effects of pollution, acidification, ocean warming, over-fishing and hypoxia (deoxygenation).
The scientific panel concluded that the combination of stresses on the ocean is creating the conditions associated with every previous major extinction of species in Earth’s history. And the speed and rate of degeneration in the ocean is far greater than anyone has predicted.
The panel concluded that many of the negative impacts previously identified are greater than the worst predictions. As a result, although difficult to assess, the first steps to globally significant extinction may have begun with a rise in the extinction threat to marine species such as reef-forming corals.
“The world’s leading experts on oceans are surprised by the rate and magnitude of changes we are seeing,” says Dan Laffoley, Marine Chair of IUCN’s World Commission on Protected Areas, Senior Advisor on Marine Science and Conservation for IUCN and co-author of the report. “The challenges for the future of the ocean are vast, but unlike previous generations, we know what now needs to happen. The time to protect the blue heart of our planet is now, today and urgent.”
“The findings are shocking,” says Dr Alex Rogers, Scientific Director of the International Programme on the State of the Ocean (IPSO) which convened the workshop. “As we considered the cumulative effect of what humankind does to the ocean, the implications became far worse than we had individually realized. This is a very serious situation demanding unequivocal action at every level. We are looking at consequences for humankind that will impact in our lifetime, and worse, our children’s and generations beyond that.”
Marine scientists from institutions around the world gathered at Oxford University under the auspices of IPSO and the IUCN. The group reviewed over 50 of the most recent research papers by world ocean experts and found firm evidence that the effects of climate change, coupled with other human-induced impacts such as over-fishing and nutrient run-off from farming, have already caused a dramatic decline in ocean health.
Increasing hypoxia and anoxia (absence of oxygen, known as ocean dead zones) combined with warming of the ocean and acidification are the three factors which have been present in every mass extinction event in Earth’s history.
There is strong scientific evidence that these three factors are combining in the ocean again, exacerbated by multiple severe stresses. The panel concluded that a new extinction event was inevitable if the current trajectory of damage continues, and could be said to have already begun.
Facts highlighted by the panel include:
• The levels of carbon being absorbed by the ocean are already far greater now than at the time of the last mass extinction of marine species, some 55 million years ago, when up to 50% of some groups of deep sea animals were wiped out.
• A single mass coral bleaching event in 1998 killed 16% of all the world’s tropical coral reefs.
• Overfishing has reduced some commercial fish stocks by more than 90%.
• New science also suggests that pollutants including flame retardant chemicals and synthetic musks found in detergents are being traced in the Polar Seas, and that these chemicals can be absorbed by tiny plastic particles in the ocean which are in turn eaten by marine creatures.
The experts agreed that adding these and other threats together means that the ocean and the ecosystems within it are unable to recover, being constantly bombarded with multiple attacks.
The report sets out a series of recommendations and calls on states, regional bodies and the United Nations to implement measures to better conserve ocean ecosystems, and in particular demands the urgent adoption of better governance of the largely unprotected high seas which make up the majority of the ocean.
For more information contact:
James Oliver, james.oliver@iucn.org
About the report’s 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. Professor Rogers 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 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.
State of the Ocean report June 2011 pdf 2011265KB
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