Seagrass can provide localized protection against ocean acidification

Brooks Hays UPI 31 Jul 18;

July 31 (UPI) -- Seagrass could serve as a local buffer against ocean acidification, protecting vulnerable species against rising levels of carbonic acid.

In addition to providing food and shelter to a variety of marine organisms, seagrass also absorbs carbon dioxide as it performs photosynthesis. Researchers with the Carnegie Institution for Science designed to models to measure whether a seagrass meadow's carbon uptake abilities could lower pH levels.

The models accounted for grass density, photosynthetic activity, water depth, currents and a variety of other factors. The results, detailed in the journal Ecological Applications, suggests seagrass can have a small, local effect on ocean acidity.

"Local stakeholders, such as California's shellfish industry, want to know whether seagrass meadows may help to counteract ocean acidification," Carnegie researcher David Koweek said in a news release. "Our results suggest that seagrass meadows along the California coast will likely offer only limited ability to counteract ocean acidification over long periods of time."

Though scientists found seagrass was unlikely to offer longterm protection, they did show seagrass meadows can offer stronger, short-term benefits during low tide and during the day when photosynthetic activity peaks.

Carbonic acid is corrosive and prevents shellfish from forming their shells out of calcium carbonate. The latest research suggests shellfish could potentially take advantage of the short-term protections offered by sea grass.

"We are starting to understand that some marine organisms, such as blue mussels, are actually able to shift the time of day in which they do most of their calcification," Koweek said. "If other organisms are able to do the same, then even brief windows of significant ocean acidification buffering by seagrass meadows may bring substantial benefits to the organisms that live in them."

RELATED How ocean acidification weakens coral skeletons
The best way to fight ocean acidification, scientists insist, is to drastically curb the amount of carbon dioxide being released into the atmosphere. But conserving sea grass could help, too.

"Although our results indicate that seagrass meadows along the California coast are not likely to offer long-term buffering to fight ocean acidification, their enduring role as habitat for marine organisms, protectors against sea level rise, and magnets of biodiversity should be more than enough reason to restore and protect these iconic ecosystems," Koweek said.

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More acidic oceans 'will affect all sea life'

Roger Harrabin BBC 23 Oct 17;

All sea life will be affected because carbon dioxide emissions from modern society are making the oceans more acidic, a major new report will say.

The eight-year study from more than 250 scientists finds that infant sea creatures will be especially harmed.

This means the number of baby cod growing to adulthood could fall to a quarter or even a 12th of today's numbers, the researchers suggest.

The assessment comes from the BIOACID project, which is led from Germany.

A brochure summarising the main outcomes will be presented to climate negotiators at their annual meeting, which this year is taking place in Bonn in November.

The Biological Impacts of Ocean Acidification report authors say some creatures may benefit directly from the chemical changes - but even these could still be adversely affected indirectly by shifts in the whole food web.

What is more, the research shows that changes through acidification will be made worse by climate change, pollution, coastal development, over-fishing and agricultural fertilisers.

Ocean acidification is happening because as CO2 from fossil fuels dissolves in seawater, it produces carbonic acid and this lowers the pH of the water.

Since the beginning of the Industrial Revolution, the average pH of global ocean surface waters have fallen from pH 8.2 to 8.1.
This represents an increase in acidity of about 26%.

The study's lead author is Prof Ulf Riebesell from the GEOMAR Helmholtz Centre for Ocean Research in Kiel.

He is a world authority on the topic and has typically communicated cautiously about the effects of acidification.

He told BBC News: "Acidification affects marine life across all groups, although to different degrees.

"Warm-water corals are generally more sensitive than cold-water corals. Clams and snails are more sensitive than crustaceans.

"And we found that early life stages are generally more affected than adult organisms.

"But even if an organism isn't directly harmed by acidification it may be affected indirectly through changes in its habitat or changes in the food web.

"At the end of the day, these changes will affect the many services the ocean provides to us."

On the agenda

Since 2009, scientists working under the BIOACID programme have studied how marine creatures are affected by acidification during different life stages; how these reactions reverberate through the marine food web; and whether the challenges can be mitigated by evolutionary adaptation.

Some research was done in the lab but other studies were conducted in the North Sea, the Baltic, the Arctic, and Papua New Guinea.

A synthesis of more than 350 publications on the effects of ocean acidification - which will be given to climate delegates at next month's summit - reveals that almost half of the marine animal species tested reacted negatively to already moderate increases in seawater CO2 concentrations.

Early life stages were affected in Atlantic cod, blue mussels, starfish, sea urchins and sea butterflies.

But an experiment with barnacles showed they were not sensitive to acidification. And some plants - like algae which use carbon for photosynthesis - may even benefit.

Dr Carol Turley, an ocean acidification expert from Plymouth Marine Labs in the UK described the BIOACID research as enormously important.

She told BBC News: "It's contributed enormous insights into the impacts that acidification can have on a wide range of marine organisms from microbes to fish.

"It's also explored how in combination with ocean warming and other stressors it might play out at the ecosystem level and affect human society.

"On the lead-up to the UN climate change negotiations in Bonn this November it is clear that the ocean and its ecosystems should not be ignored."

The conference is being held in Germany but it is being chaired by Fiji, which wants delegates to give due prominence to the effects of CO2 on the ocean.

Ocean acidification is deadly threat to marine life, finds eight-year study
Plastic pollution, overfishing, global warming and increased acidification from burning fossil fuels means oceans are increasingly hostile to marine life
Fiona Harvey The Guardian 23 Oct 17;

If the outlook for marine life was already looking bleak – torrents of plastic that can suffocate and starve fish, overfishing, diverse forms of human pollution that create dead zones, the effects of global warming which is bleaching coral reefs and threatening coldwater species – another threat is quietly adding to the toxic soup.

Ocean acidification is progressing rapidly around the world, new research has found, and its combination with the other threats to marine life is proving deadly. Many organisms that could withstand a certain amount of acidification are at risk of losing this adaptive ability owing to pollution from plastics, and the extra stress from global warming.

The conclusions come from an eight-year study into the effects of ocean acidification which found our increasingly acid seas – a byproduct of burning fossil fuels – are becoming more hostile to vital marine life.

“Since ocean acidification happens extremely fast compared to natural processes, only organisms with short generation times, such as micro-organisms, are able to keep up,” the authors of the study Exploring Ocean Change: Biological Impacts of Ocean Acidification found.

Marine life such as crustaceans and organisms that create calcified shelters for themselves in the oceans were thought to be most at risk, because acid seas would hinder them forming shells. However, the research shows that while these are in danger, perhaps surprisingly, some – such as barnacles – are often unaffected, while the damage from acidification is also felt much higher up the food chain, into big food fish species.

Ocean acidification can reduce the survival prospects of some species early in their lives, with knock-on effects. For instance, the scientists found that by the end of the century, the size of Atlantic cod in the Baltic and Barents Sea might be reduced to only a quarter of the size they are today, because of acidification.

Peter Thomson, UN ambassador for the oceans and a diplomat from Fiji, which is hosting this year’s UN climate change conference in Bonn, urged people to think of the oceans in the same terms as they do the climate. “We are all aware of climate change, but we need to talk more about ocean change, and the effects of acidification, warming, plastic pollution, dead zones and so on,” he said. “The world must know that we have a plan to save the ocean. What is required over the next three years is concerted action.”

The eight-year study was carried out by the Biological Impacts of Ocean Acidification group (known as Bioacid), a German network of researchers, with the support of the German government, and involved more than 250 scientists investigating how marine life is responding to acidification, and examining research from around the world. The study was initiated well before governmentssigned a global agreement on climate change at Paris in 2015, and highlights how the Paris agreement to hold warming to no more than 2C may not be enough to prevent further acidification of the world’s seas.

Governments will meet in Bonn in November to discuss the next steps on the road to fulfilling the requirements of the Paris agreement, and the researchers are hoping to persuade attendees to take action on ocean acidification as well.

Ocean acidification is another effect of pouring carbon dioxide into the atmosphere, as the gas dissolves in seawater to produce weak carbonic acid. Since the industrial revolution, the average pH of the ocean has been found to have fallen from 8.2 to 8.1, which may seem small but corresponds to an increase in acidity of about 26%. Measures to reduce the amount of carbon dioxide reaching the atmosphere can help to slow down this process, but only measures that actively remove carbon already in the atmosphere will halt it, because of the huge stock of carbon already in the air from the burning of fossil fuels.

Worse still, the effects of acidification can intensify the effects of global warming, in a dangerous feedback loop. The researchers pointed to a form of planktonic alga known as Emiliania huxleyi, which in laboratory experiments was able to adapt to some extent to counter the negative effects acidification had upon it. But in a field experiment, the results were quite different as the extra stresses present at sea meant it was not able to form the extensive blooms it naturally develops. As these blooms help to transport carbon dioxide from the surface to the deep ocean, and produce the gas dimethyl sulfide that can help suppress global warming, a downturn in this species “will therefore severely feed back on the climate system”.

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Survival of coral reefs requires radical rethink of what conservation means, say scientists

Reef conservation must not be an attempt to restore reefs of the past, but to identify the parts essential to their continued existence, and protect those.
Michael Slezak The Guardian 31 May 17;

The survival of coral reefs requires a radical rethink of what conservation means, as well as embracing some of the changes they are undergoing, according to a paper by leading coral reef scientists.

“Helping coral reefs to safely navigate the Anthropocene is a profound challenge for multiscale governance,” the scientists say in a paper published today in the journal Nature.

They argue reef conservation must no longer be seen as an attempt to restore reefs of the past, or conserve their existing values, but rather to identify the parts of reefs that are essential to their continued existence, and protect those.

The paper comes amid increased urgency from conservationists and reef managers around the world, sparked by the worst global bleaching event in recorded history. It caused mass die-offs in every major coral reef region of the world. On the Great Barrier Reef alone, it is estimated that about half the coral was killed in 2016 and 2017.

In the paper, the scientists argue saving the world’s reefs requires the acceptance that the reefs of the future will look very different to those of today, and humans may need to help them adapt – perhaps by intervening to increase the proportion of coral species that are tolerant to rising temperatures.

“In the coming centuries, reefs will run the gauntlet of climate change, and rising temperatures will transform them into new configurations, unlike anything observed previously by humans,” the paper says.

But the overall message was one of hope, said lead author of the paper Terry Hughes from James Cook University in Australia.

“There’s no shortage of people saying reefs will be dead by 2030 or whatever,” Hughes said. “They are going to be different systems with a different mix of species but if we throw the kitchen sink at it and especially deal with climate change then we will have functioning reefs that will sustain and repair themselves and be of some use to people,” he said.

The group of scientists, which includes both biologists and social scientists, argue the approach to reef conservation must change in several ways.

As coral reefs change, the authors say scientists and conservationists must focus on aspects of reef ecosystems that are the most important to their continued existence. They say biodiversity is no longer the most important value to protect, since some species are more important to the ecosystem than others.

They also suggest that helping reefs adapt may become an important strategy. “Ecosystem composition change is already occurring naturally, as corals respond and adapt to climate change, and could be promoted further through efforts to actively manipulate ecosystem configurations,” they write.

Besides embracing the fact that reefs will never be the same, they argue research and conservation must shift from the most direct impacts on reefs, and instead identify and target the root causes.

For example, rather than focusing just on the role herbivorous fish play in suppressing seaweed, thereby allowing reefs to recover, conservation efforts should focus on what drives the overfishing of those fish – such as poverty and market demands. “We tend to propose bandaids rather than dealing with the root cause of the issue,” Hughes said.

Underlying the finding that reefs will continue to survive is the assumption that agreements made at Paris to keep global warming to “well below 2C” are successful.

The researchers reviewed published experiments that examined the response of coral to rising temperatures, and found none that looked at the carbon dioxide levels they say reefs are likely to experience over the next century. Instead, those studies universally examined much more extreme scenarios, equivalent to several degrees of global warming.

“Most of the coral reef literature assumes business-as-usual emissions to the end of the century, which would result in global warming of 4, 5 or 6C,” says Hughes. “We will never get there – not because people will become more and more concerned about coral reefs – but because Florida will go under water and that will get people’s attention.”

Similarly, the authors said experiments examining the impacts of acidification looked at exaggerated scenarios, and the researchers said there were some suggestions acidification may not have a large impact on the growth of coral.

The understanding that coral reefs will never be the same is already affecting management practices around the world.

In Australia, the Guardian revealed last week that advisers to the government’s plan to protect the Great Barrier Reef have said it must stop trying to “improve” and restore the natural heritage values, and instead should aim to “maintain the ecological function” of the reef, while accepting its overall health would inevitably decline.

Similarly, sources have told the Guardian that discussions are occurring within Unesco, over how to protect natural heritage values, given that climate change means many heritage sites will inevitably be altered.

Not all coral reef biologists are supportive of efforts to manipulate reef ecosystems.

Justin Marshall from the University of Queensland said the new paper made many good points, but that he did not think attempts to pick and choose parts of reefs to save would be successful. “We’re consistently crap at playing God – or playing Darwin,” Marshall said, adding that ecosystems were too complex to predict the outcomes of particular interventions.

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Rising CO2 threatens coral and people who use reefs

Shoreline societies will lose fish, storm protection
DUKE UNIVERSITY EurekAlert 9 Nov 16;

DURHAM, N.C. -- As atmospheric carbon dioxide (CO2) levels rise, very few coral reef ecosystems will be spared the impacts of ocean acidification or sea surface temperature rise, according to a new analysis. The damage will cause the most immediate and serious threats where human dependence on reefs is highest.

A new analysis in the journal Plos One, led by Duke University and the Université de Bretagne Occidentale, suggests that by 2050, Western Mexico, Micronesia, Indonesia, parts of Australia and Southeast Asia will bear the brunt of rising temperatures. Reef damage will result in lost fish habitats and shoreline protection, jeopardizing the lives and economic prosperity of people who depend on reefs for tourism and food.

"Some scientists have held out hope that there would be reef areas that could escape the harm of climate change, but we find that most reefs will be affected by either warmer seas or more acidic oceans," said Linwood Pendleton, the study's lead author, a senior scholar at Duke University's Nicholas Institute for Environmental Policy Solutions and an International Chair of Excellence at the European Institute of Marine Studies. "2016 has been one of the worst years in memory for coral bleaching. This fact is demonstrated by this year's bleaching event that affected nearly all of the Great Barrier Reef."

The study builds on previous analyses to identify exactly how people and coral reefs are affected by a high-CO2 future and suggests pathways to help deal with changes. The authors mapped human dependence at the country level, scoring for two indicators: shoreline protection and coral reef fisheries. Simultaneously, the authors mapped the largely unavoidable impacts of increased sea surface temperature and ocean acidification.

Using data from the maps, the study predicts that the countries of Oceania will be among the first to face the greatest environmental stresses from climate change and ocean acidification, followed by the Coral Triangle countries of Southeast Asia and other parts of Australia -- all areas with high dependence on coral reefs.

Countries most likely to experience severe ocean acidification are generally different from those that will experience the earliest onset of coral bleaching. Acidification is projected to be worse for Baja California (Mexico), Japan, China, and southern Australia because they are at the upper and lower latitudinal bounds of coral reef distribution and thus generally in cooler waters that naturally carry more CO2.

"The response of non-governmental organizations, nonprofits, and labor and trade organizations will be critical in mounting a response to the threats posed by warming and acidification because these organizations represent the people that will be most severely impacted by the failure of coral reef fisheries," said Chris Langdon, a professor in the Department of Marine Biology and Fisheries at the University of Miami. "These groups must speak up for the individuals they represent so that their local, regional and national government agencies see that action is needed."

The authors say policy action to combat the threats of ocean acidification and surface temperature rise must be informed by data and science, but the research community is still doing a poor job of collecting this information where these threats are most substantial for people. Many of the countries most dependent upon coral reefs are also the countries for which we have the least robust data on ocean acidification, especially the South China Sea, an area of high human dependence and equally high political tensions.

"Because sea temperature and ocean acidification is largely beyond the control of the communities that depend on coral reefs, it is critical that we constantly monitor conditions there," said Adrien Comte, a Ph.D. candidate at the Université de Bretagne Occidentale. "Better environmental management can help delay the impacts on corals, and stepwise actions to improve monitoring and plan for adaptation should be funded."

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View a summary of the findings and interactive maps http://arcg.is/2cJqsep. The article will be available online at 2 p.m. ET, November 9: https://nicholasinstitute.duke.edu/ocean/publications/coral-reefs-and-people-high-co2-world-where-can-science-make-difference-people.

This work was supported with grant funding from the National Social Environmental Synthesis Center, the Prince Albert II Foundation, the "Laboratoire d'Excellence" LabexMER (ANR-10-LABX-19), and the French government under the program "Investissements d'Avenir" and the Region of Brittany.

CITATION: L. Pendleton, A. Comte, C. Langdon, et. al. 2016. "Coral Reefs and People in a High CO2 World: Where Can Science Make a Difference to People?" PLOS ONE: DOI: 10.1371/journal.pone.0164699.

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Soaring ocean temperature is 'greatest hidden challenge of our generation'

IUCN report warns that ‘truly staggering’ rate of warming is changing the behaviour of marine species, reducing fishing zones and spreading disease
Oliver Milman The Guardian 5 Sep 16;

The soaring temperature of the oceans is the “greatest hidden challenge of our generation” that is altering the make-up of marine species, shrinking fishing areas and starting to spread disease to humans, according to the most comprehensive analysis yet of ocean warming.

The oceans have already sucked up an enormous amount of heat due to escalating greenhouse gas emissions, affecting marine species from microbes to whales, according to an International Union for Conservation of Nature (IUCN) report involving the work of 80 scientists from a dozen countries.

The profound changes underway in the oceans are starting to impact people, the report states. “Due to a domino effect, key human sectors are at threat, especially fisheries, aquaculture, coastal risk management, health and coastal tourism.”

Dan Laffoley, IUCN marine adviser and one of the report’s lead authors, said: “What we are seeing now is running well ahead of what we can cope with. The overall outlook is pretty gloomy.

“We perhaps haven’t realised the gross effect we are having on the oceans, we don’t appreciate what they do for us. We are locking ourselves into a future where a lot of the poorer people in the world will miss out.”

The scale of warming in the ocean, which covers around 70% of the planet, is “truly staggering”, the report states. The upper few metres of ocean have warmed by around 0.13C a decade since the start of the 20th century, with a 1-4C increase in global ocean warming by the end of this century.

The ocean has absorbed more than 90% of the extra heat created by human activity. If the same amount of heat that has been buried in the upper 2km of the ocean had gone into the atmosphere, the surface of the Earth would have warmed by a devastating 36C, rather than 1C, over the past century.

At some point, the report says, warming waters could unlock billions of tonnes of frozen methane, a powerful greenhouse gas, from the seabed and cook the surface of the planet. This could occur even if emissions are drastically cut, due to the lag time between emitting greenhouse gases and their visible consequences.

Warming is already causing fish, seabirds, sea turtles, jellyfish and other species to change their behaviour and habitat, it says. Species are fleeing to the cooler poles, away from the equator, at a rate that is up to five times faster than the shifts seen by species on land.

Even in the north Atlantic, fish will move northwards by nearly 30km per decade until 2050 in search of suitable temperatures, with shifts already documented for pilchard, anchovy, mackerel and herring.

The warming is having its greatest impact upon the building blocks of life in the seas, such as phytoplankton, zooplankton and krill. Changes in abundance and reproduction are, in turn, feeding their way up the food chain, with some fish pushed out of their preferred range and others diminished by invasive arrivals.

With more than 550 types of marine fishes and invertebrates already considered threatened, ocean warming will exacerbate the declines of some species, the report also found.

The movement of fish will create winners and losers among the 4.3 billion people in the world who rely heavily upon fish for sustenance. In south-east Asia, harvests from fisheries could drop by nearly a third by 2050 if emissions are not severely curtailed. Global production from capture fisheries has already levelled off at 90m tonnes a year, mainly due to overfishing, at a time when millions more tonnes will need to be caught to feed a human population expected to grow to 9 billion by 2050.

Humans are also set to suffer from the spread of disease as the ocean continues to heat up. The IUCN report found there is growing evidence of vibrio bacterial disease, which can cause cholera, and harmful algal bloom species that can cause food poisoning. People are also being affected by more severe, if not more numerous, hurricanes due to the extra energy in the ocean and atmosphere.

Coral reefs, which support around a quarter of all marine species, are suffering from episodes of bleaching that have included three-fold in the past 30 years. This bleaching occurs when prolonged high temperatures cause coral to expel its symbiotic algae, causing it to whiten and ultimately die, such as the mass mortality that has gripped the Great Barrier Reef.

Ocean acidification, where rising carbon dioxide absorption increases the acidity of the water, is making it harder for animals such as crabs, shrimps and clams to form their calcium carbonate shells.

The IUCN report recommends expanding protected areas of the ocean and, above all, reduce the amount of heat-trapping gases pumped into the atmosphere.

“The only way to preserve the rich diversity of marine life, and to safeguard the protection and resources the ocean provides us with, is to cut greenhouse gas emissions rapidly and substantially,” said Inger Andersen, director general of the IUCN.


Warming oceans are 'sick,' global scientists warn
Kerry Sheridan Yahoo News 5 Sep 16;

Global warming is making the oceans sicker than ever before, spreading disease among animals and humans and threatening food security across the planet, a major scientific report said on Monday.

The findings, based on peer-reviewed research, were compiled by 80 scientists from 12 countries, experts said at the International Union for Conservation of Nature (IUCN) World Conservation Congress in Hawaii.

"We all know that the oceans sustain this planet. We all know that the oceans provide every second breath we take," IUCN Director General Inger Andersen told reporters at the meeting, which has drawn 9,000 leaders and environmentalists to Honolulu.

"And yet we are making the oceans sick."

The report, "Explaining Ocean Warming," is the "most comprehensive, most systematic study we have ever undertaken on the consequence of this warming on the ocean," co-lead author Dan Laffoley said.

The world's waters have absorbed more than 93 percent of the enhanced heating from climate change since the 1970s, curbing the heat felt on land but drastically altering the rhythm of life in the ocean, he said.

"The ocean has been shielding us and the consequences of this are absolutely massive," said Laffoley, marine vice chair of the World Commission on Protected Areas at IUCN.

- Microbes to whales -

The study included every major marine ecosystem, containing everything from microbes to whales, including the deep ocean.

It documents evidence of jellyfish, seabirds and plankton shifting toward the cooler poles by up to 10 degrees latitude.

The movement in the marine environment is "1.5 to five times as fast as anything we are seeing on the ground," Laffoley said. "We are changing the seasons in the ocean."

The higher temperatures will probably change the sex ratio of turtles in the future because females are more likely to be born in warmer temperatures.

The heat also means microbes dominate larger areas of the ocean.

"When you look overall, you see a comprehensive and worrying set of consequences," Laffoley said.

More than 25 percent of the report's information is new, published in peer-reviewed journals since 2014, including studies showing that global warming is affecting weather patterns and making storms more common.

The study includes evidence that ocean warming "is causing increased disease in plant and animal populations," it said.

Pathogens such as cholera-bearing bacteria and toxic algal blooms that can cause neurological illnesses such as ciguatera poisoning spread more easily in warm water, with direct impact on human health.

"We are no longer the casual observers in the room," Laffoley said.

"What we have done is unwittingly put ourselves in the test tube where the experiment is being undertaken."

- Cut greenhouse gases -

Meanwhile, the hotter oceans have killed off coral reefs at an unprecedented rate, reducing fish species by eliminating their habitats.

The loss of reefs cuts down on the abundance of certain fish, with implications for food security.

"In Southeast Asia, harvests from marine fisheries are expected to fall by between 10 percent and 30 percent by 2050 relative to 1970-2000, as the distributions of fish species shift," said the report.

The report highlights the need for swift action on renewable energies, experts said.

"We need to cut greenhouse gases," said Carl Gustaf Lundin, director of the global marine and polar program at IUCN.

"There is no doubt in all our minds that we are the cause of this," he added.

"We know what the solutions are. We need to get on with it."

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Risk of ‘sea desertification’ challenges Vietnam

VietNamNet Bridge 11 Jul 16;

Climate change is one of the reasons behind sea desertification. It warms the air temperature and sea water and lowers nitrogen, phosphorus and oxygen concentration, thus paving the way for the formation of a ‘dead sea area’ or desertification of the sea.

‘Sea desertification’ is a new terminology used to describe the area where all sea creatures cannot live because of poor natural conditions, water quality and land.

According to experts from the General Department of Sea and Islands, there are six factors which can lead to sea desertification. First, climate change.

Second, the discharging of hazardous waste to the sea, causing greenhouse gas emissions. This causes an increase in the acid concentration in the sea, disrupts the supply of nutrients to the sea, reduces biodiversity and interrupts the periodic operation of oxygen, nitrogen and phosphorous.

The ocean acidification causes coral bleaching, habitat for sea creatures changing, the water quality degrading and nutrients decreasing, which then causes desertification.

Climate change is one of the reasons behind sea desertification. It warms the air temperature and sea water and lowers nitrogen, phosphorus and oxygen concentration, thus paving the way for the formation of a ‘dead sea area’ or desertification of the sea.
The third reason lies in ocean currents.

Fourth, the destruction of important marine ecosystems such as coral ecosystems, mangrove and sea grass ecosystems by explosives and toxic chemicals. Fifth, the rapid development of coastal urban areas and industrial zones which spoils the air quality, surface water and sea water.

Finally, the air transportation, which concentrates in some certain areas.

In general, experts say the major reason behind desertification is sea pollution caused by human activities.

According to Du Van Toan from the General Department of Sea and Islands, it is necessary to conduct research to determine the origin and find the development, location and classification mechanism, and to build up a sea desertification map of coastal waters and offshore of Vietnam.

It is also necessary to conduct research to assess the possible impact on the environment, socio-economic development and security in the sea desert areas.

Toan has urged a new monitoring system with an aim to keep special control over the areas prone to desertification.

International cooperation in scientific research will play a very important role in preventing sea desertification. Residents in coastal areas need to be warned about the dangerous phenomenon and asked to cooperate to prevent it.

Vietnam now has 16 MPAs (marine protection areas). Though they cover a small area, just 0.3 percent of total waters, they still can help maintain ecological balance if they can be managed well.

MPAs are believed to create a restoration effect after five years, and later create a spillover effect which helps disperse nutrients to the surrounding areas.

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Singapore ready to deal with threat to corals

Audrey Tan, Straits Times AsiaOne 4 Mar 15;

Safeguards targeting rarer coral species to be put in place if seas become too warm: NParks

Even though Singapore has lost over 60 per cent of its coral reefs through extensive land reclamation, its waters are still home to about a third of the world's hard coral species. But they could still be under threat - this time from warming seas as a result of climate change.

The National Parks Board (NParks) is ready to jump into action if sea surface temperatures creep up to a point that Singapore's corals are in danger of bleaching.

A coral safeguard programme targeting rarer coral species will be implemented, said Dr Karenne Tun, deputy director of the coastal and marine division at NParks' National Biodiversity Centre.

"We will collect fragments of these species from as many colonies as we can find, and grow them out in various reef areas as well as in aquaria, to ensure that we are able to maintain the population," she told The Straits Times. "We will also out-plant them back on the reefs after the bleaching event passes."

Meanwhile, NParks has initiated monitoring schemes to better understand how elevated sea surface temperatures may influence the photosynthetic responses of corals.

Coral reefs cover just 284,000 sq km of the ocean floor - about 0.1 per cent of the total ocean area - but they support a surprising amount of biodiversity. Around the world, these underwater palaces support about 30 per cent of all described marine species.

In Singapore waters, there are more than 250 species of hard corals. The total reef area here is an estimated 13.25 sq km.

But even as a global climate pact was forged in Paris last December, coral reefs worldwide are reeling from the impact of climate change.

Marine scientists say coral reefs are one of the habitats most under threat, due to the dual effects of ocean warming and ocean acidification. "Ocean warming is a direct impact of climate change that increases temperature stress on corals," said Dr Intan Suci Nurhati, a coral researcher from Singapore-MIT Alliance for Research and Technology.

When carbon dioxide dissolves in the ocean, carbonic acid is formed. The increasing acidity will lead to higher rates of erosion of the physical structure of reefs, said Assistant Professor Huang Danwei, a marine biologist from the National University of Singapore's (NUS) department of biological sciences. Current and projected rates of global warming mean many stony corals will expel the symbiotic microalgae living within them and nourishing them, Prof Huang added. But expelling the algae causes coral bleaching.

In October last year, science journal Nature reported widespread coral bleaching. This caused the United States National Oceanic and Atmospheric Administration to officially declare a global bleaching event on Oct 8, the third in recorded history, after 1998 and 2010.

These were El Nino years, referring to the phenomenon linked to prolonged warmer weather that is expected to continue this year as well, with scientists warning of bleaching events. In 1998, about 25 per cent of corals here died, while 5 per cent of them did so in 2010.

Prof Huang, who runs the Reef Ecology Lab at NUS, said coral reefs can protect shorelines and support recreation and tourism.

"The dive trail at the Sisters' Islands Marine Park attests to that. We have many more coral reefs that have the potential to become world-class dive sites, right in our backyard."


Viruses 'may be keeping coral reefs healthy'
Straits Times 4 Mar 16;

Coral reefs are one of the most vibrant and colourful habitats of the ocean, but the key to their health could lie in organisms not visible to the naked eye.

Microbial communities comprising viruses and bacteria could be the unlikely drivers of coral reef health, according to research by a marine biologist from Nanyang Technological University .

During a study of a pristine ring of coral in the Chagos Archipelago in the Indian Ocean, Associate Professor Federico Lauro found that the water within the coral ring contained more of a type of virus than the surrounding water, despite constant water exchange.

The Italian's research has indicated that it could be these viruses that are helping the coral reefs there to thrive.

Known as bacteriophages, the viruses can infect and break down a type of cyanobacteria - organisms that make their own food through photosynthesis - called Synechococcus. The destruction of Synechococcus releases nutrients such as nitrogen- and phosphorous-based compounds, which nourish the corals.

"Not all viruses are bad. Some of them are good and, in this case, they could play a role in cycling nutrients," said Prof Lauro.

"In a healthy human, there is a balance of the different types of microbes in the body, and it is the same for coral reefs."

The Chagos Archipelago is uninhabited except for military personnel, and is part of a marine protected area established by Britain. The water there is clean, and the coral reefs in the area are considered among the healthiest in the world.

Prof Lauro's research has wider implications for coral reef conservation, as scientists can now look beyond physical factors, such as sedimentation, to determine why reefs are dying and how to restore them.

"There is a clear indication that the viruses have an effect on the Chagos coral atoll, and it is interesting to study how biological factors are affecting other reefs," he said .

The research was conducted aboard his own recreational sailing boat, the 18.5m Indigo V. "This shows that you don't need a large oceanographic vessel to do good science, and a lot more ocean samples can be collected by recreational boat owners who are sailing the world in their own time," he said.

His study cost $70,000, a fraction of what a similar study on board a large oceanographic vessel with high-tech scientific devices could cost. For his work, he clinched the prestigious Lowell Thomas Award for Innovation in Conservation last November.

This is an international award which last year was given to explorers who exhibit excellence and innovation in conservation, with emphasis on emerging techniques and technologies. Past winners include Sir David Attenborough, the golden voice of nature documentaries, and Edwin "Buzz" Aldrin, one of the first men to walk on the moon.

On his win, Prof Lauro said: "It was surprising, considering that the past winners like Sir David Attenborough are so good, but I hope that the win will help us get funding for the Indigo project, for more exciting science."

He is due to set off on another research trip to the Indian Ocean on board Indigo V later this month.

Assistant Professor Huang Danwei of the National University of Singapore's Department of Biological Sciences said: "The methods established (by Prof Lauro) also pave the way for a convenient approach for even non-scientists to contribute to the monitoring of various marine environments, including coral reefs, which have distinct microbial signatures."

Audrey Tan

Polluted waters: Corals fight back
Coral reefs are the world's underwater gardens and guardians of life. But, as oceans warm and become more acidic due to climate change, these important habitats are at risk. The good news is that nature is resilient. New scientific research has uncovered more information about coral reefs, which could help in their conservation. The Straits Times takes a look at the links between climate change and coral reefs.
Audrey Tan Straits Times 4 Mar 16;

Murky waters full of sediment may make it difficult for scuba divers to explore under water, but they have a far more ominous impact on marine life.

Corals, in particular, are exceptionally vulnerable. As well as grappling with the effects of climate change, sedimentation caused by land reclamation or pollution is also posing a challenge.

Sunlight does not penetrate sedimented waters as well as in clear waters. This affects the photosynthetic ability of the microalgae living in the coral to produce food, which nourishes the host.

High levels of sediment in the water can also physically smother corals and affect their reproduction.

Unlike broadcast-spawning coral species, which release male and female sex cells in a spectacular fashion, colouring the waters a milky white, brooding coral species establish new colonies in a less extravagant way.

The fertilised egg, or larva, is released into the water column and carried to another part of the ocean, where it starts developing new colonies. But sediment collecting in coral crevices could prevent the larva from being dislodged or hinder its development.

Nature, however, is resilient.

Scientists from the National University of Singapore's Tropical Marine Science Institute (TMSI) have discovered an encouraging adaptation in the native blue coral Heliopora coerulea that seems to help it thrive in sedimented waters.

During brooding, the female Heliopora coerulea holds a fertilised egg using feathery tentacles. The inflated tentacles help to elevate the larvae above the sediment layer that has accumulated on the colonies.

"The inflated polyps protrude from accumulated sediment in the colony crevices, thus raising the brooded larvae above the layers," said Dr Toh Tai Chong, 31, a research fellow at TMSI who led the project.

The discovery was recently published in science journal Marine And Freshwater Behavior And Physiology.

Dr Toh and Mr Lionel Ng, a research assistant at TMSI, were conducting coral reef surveys at the offshore islands south of Singapore in April 2014 as part of a study to assess the effectiveness of reef rehabilitation efforts here when they noticed a patch of white while swimming over some Heliopora coerulea corals.

"It looked like a dense white mat was laid over the corals," said Mr Ng, 32.

The researchers believe their findings could help with the conservation of Heliopora coerulea, which is listed by the International Union for Conservation of Nature as being vulnerable to extinction.

"We have a lot more broadcast spawners than brooders, and little is known about the reproductive biology of Heliopora coerulea," said Dr Toh.

The United States National Oceanic and Atmospheric Administration estimates that while three-quarters of stony corals are broadcast spawners, the remaining quarter of coral species are brooders.

"Since the Heliopora coerulea broods only once a year around April, this discovery enhances our existing knowledge on the biology of reef organisms, which could help us better manage the areas they are found in to reduce disturbance and further sedimentation during the reproductive season," said Mr Ng.

Dr Toh also pointed out that since sedimentation affects all types of coral, further research could look into the different adaptation strategies to improve our understanding of how Singapore's reefs remain resilient.

This also facilitates the conservation of more vulnerable species through measures such as artificial propagation to reduce the risks of local extinction.

Dr Karenne Tun, deputy director of the coastal and marine division at the National Parks Board's (NParks) National Biodiversity Centre, said coral reefs will ensure the availability of marine-based resources, such as food and breeding spaces, and continue to support the ecosystem's resilience to a changing climate.

"NParks continually works with various coral reef researchers (here) to increase our knowledge of Singapore's coral reefs and develop better management strategies of coral reefs through our targeted conservation programmes, such as the setting up of the coral nursery and the initiation of a coral bleaching monitoring programme."

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Carbon emission cuts only way to save coral from acid seas: study

Alister Doyle, Reuters Yahoo News 25 Feb 16;

OSLO (Reuters) - Corals under threat from acid seas can only be saved by deep cuts in carbon dioxide emissions, scientists said on Wednesday, and engineering the chemistry of sea water around coral reefs was only possible on a very small scale.

In a U.S.-led study, scientists mixed chemicals into a lagoon, cut off from the sea at low tide, at Australia's One Tree Island to locally reverse the global trend of acidification that makes it harder for corals to build their stony skeletons.

They showed that the coral, part of Australia's Great Barrier reef, grew better when bathed in seawater mimicking conditions before the Industrial Revolution, which ushered in widespread burning of fossil fuels that release carbon dioxide.

Their study, the first to isolate the impact of acidification from other damaging factors such as rising temperatures and pollution, warned that "technical challenges ... would probably make it infeasible at anything but highly localized scales (for example, protected bays, lagoons)."

"The only real, lasting way to protect coral reefs is to make deep cuts in our carbon dioxide emissions," the study's co-author, Ken Caldeira, from the Carnegie Institution for Science in Stanford, California, said.

Carbon dioxide forms a weak acid when mixed with water, undermining the ability of creatures such as corals, crabs, lobsters or oysters to build protective shells.

"Ocean acidification is already taking its toll on coral reef communities. This is no longer a fear for the future; it is the reality of today," lead author, Rebecca Albright, also from the Carnegie Institution, said in a statement of the findings in the journal Nature.

An international report in 2013 said today's pace of ocean acidification is the fastest in 55 million years.

Corals alone contribute almost $30 billion a year to world economies - as nurseries for fish, tourist attractions or protective barriers from storms - according to the U.S. National Oceanic and Atmospheric Administration.

Reefs are also under threat from record ocean temperatures, compounded by an El Nino weather event in the Pacific.

Governments agreed a deal in Paris in December to cut greenhouse gas emissions.

(Editing by Louise Ireland)

Read more!

Marine food chains at risk of collapse, extensive study of world's oceans finds

Important ecosystems could be massively damaged by 2050 unless greenhouse gas emissions and localised pollution is drastically reduced, researchers say
Oliver Milman The Guardian 13 Oct 15;

The food chains of the world’s oceans are at risk of collapse due to the release of greenhouse gases, overfishing and localised pollution, a stark new analysis shows.

A study of 632 published experiments of the world’s oceans, from tropical to arctic waters, spanning coral reefs and the open seas, found that climate change is whittling away the diversity and abundance of marine species.

The paper, published in the Proceedings of the National Academy of Sciences, found there was “limited scope” for animals to deal with warming waters and acidification, with very few species escaping the negative impact of increasing carbon dioxide dissolution in the oceans.

The world’s oceans absorb about a third of all the carbon dioxide emitted by the burning of fossil fuels. The ocean has warmed by about 1C since pre-industrial times, and the water increased to be 30% more acidic.

The acidification of the ocean, where the pH of water drops as it absorbs carbon dioxide, will make it hard for creatures such as coral, oysters and mussels to form the shells and structures that sustain them. Meanwhile, warming waters are changing the behaviour and habitat range of fish.

The overarching analysis of these changes, led by the University of Adelaide, found that the amount of plankton will increase with warming water but this abundance of food will not translate to improved results higher up the food chain.

“There is more food for small herbivores, such as fish, sea snails and shrimps, but because the warming has driven up metabolism rates the growth rate of these animals is decreasing,” said associate professor Ivan Nagelkerken of Adelaide University. “As there is less prey available, that means fewer opportunities for carnivores. There’s a cascading effect up the food chain.

“Overall, we found there’s a decrease in species diversity and abundance irrespective of what ecosystem we are looking at. These are broad scale impacts, made worse when you combine the effect of warming with acidification.

“We are seeing an increase in hypoxia, which decreases the oxygen content in water, and also added stressors such as overfishing and direct pollution. These added pressures are taking away the opportunity for species to adapt to climate change.”

The research adds to recent warnings over the state of the oceans, with the world experiencing the third global bleaching of coral reefs.

Since 2014, a massive underwater heatwave, driven by climate change, has caused corals to lose their brilliance and die in every ocean. By the end of this year 38% of the world’s reefs will have been affected. About 5% will have died.

Coral reefs make up just 0.1% of the ocean’s floor but nurture 25% of the world’s marine species. There are concerns that ecosystems such as Australia’s Great Barrier Reef, which has lost half its coral cover over the past 30 years, could be massively diminished by 2050 unless greenhouse gas emissions are slashed and localised pollution is curbed.

Meanwhile, warming of the oceans is causing water to thermally expand, fuelling sea level rises caused by melting land ice. Research released in the US on Monday found that Antarctic ice is melting so fast that the whole continent could be at risk by 2100, with severe consequences for coastal communities.

Problems in the ocean’s food chains will be a direct concern for hundreds of millions of people who rely upon seafood for sustenance, medicines and income. The loss of coral reefs could also worsen coastal erosion due to their role in protecting shorelines from storms and cyclones.

“These effects are happening now and will only be exacerbated in the next 50 to 100 years,” Nagelkerken said. “We are already seeing strange things such as the invasion of tropical species into temperate waters off south-eastern Australia. But if we reduce additional stressors such as overfishing and pollution, we can give species a better chance to adapt to climate change.”


Global marine analysis suggests food chain collapse
University of Adelaide ScienceAlert 12 Oct 15;

A world-first global analysis of marine responses to climbing human carbon dioxide emissions has painted a grim picture of future fisheries and ocean ecosystems.

Published today in the journal Proceedings of the National Academy of Sciences (PNAS), marine ecologists from the University of Adelaide say the expected ocean acidification and warming is likely to produce a reduction in diversity and numbers of various key species that underpin marine ecosystems around the world.

"This 'simplification' of our oceans will have profound consequences for our current way of life, particularly for coastal populations and those that rely on oceans for food and trade," says Associate Professor Ivan Nagelkerken, Australian Research Council (ARC) Future Fellow with the University's Environment Institute.

Associate Professor Nagelkerken and fellow University of Adelaide marine ecologist Professor Sean Connell have conducted a 'meta-analysis' of the data from 632 published experiments covering tropical to artic waters, and a range of ecosystems from coral reefs, through kelp forests to open oceans.

"We know relatively little about how climate change will affect the marine environment," says Professor Connell. "Until now, there has been almost total reliance on qualitative reviews and perspectives of potential global change. Where quantitative assessments exist, they typically focus on single stressors, single ecosystems or single species.

"This analysis combines the results of all these experiments to study the combined effects of multiple stressors on whole communities, including species interactions and different measures of responses to climate change."

The researchers found that there would be "limited scope" for acclimation to warmer waters and acidification. Very few species will escape the negative effects of increasing CO2, with an expected large reduction in species diversity and abundance across the globe. One exception will be microorganisms, which are expected to increase in number and diversity.

From a total food web point of view, primary production from the smallest plankton is expected to increase in the warmer waters but this often doesn't translate into secondary production (the zooplankton and smaller fish) which shows decreased productivity under ocean acidification.

"With higher metabolic rates in the warmer water, and therefore a greater demand for food, there is a mismatch with less food available for carnivores ─ the bigger fish that fisheries industries are based around," says Associate Professor Nagelkerken. "There will be a species collapse from the top of the food chain down."

The analysis also showed that with warmer waters or increased acidification or both, there would be deleterious impacts on habitat-forming species for example coral, oysters and mussels. Any slight change in the health of habitats would have a broad impact on a wide range of species these reefs harbour.

Another finding was that acidification would lead to a decline in dimethylsulfide gas (DMS) production by ocean plankton which helps cloud formation and therefore in controlling Earth's heat exchange.

Journal Reference:

Ivan Nagelkerken and Sean D. Connell. Global alteration of ocean ecosystem functioning due to increasing human CO2 emissions. PNAS, October 12, 2015 DOI: 10.1073/pnas.1510856112

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Stop burning fossil fuels now: there is no CO2 'technofix', scientists warn

Researchers have demonstrated that even if a geoengineering solution to CO2 emissions could be found, it wouldn’t be enough to save the oceans
Tim Radford The Guardian 3 Aug 15;

German researchers have demonstrated once again that the best way to limit climate change is to stop burning fossil fuels now.

In a “thought experiment” they tried another option: the future dramatic removal of huge volumes of carbon dioxide from the atmosphere. This would, they concluded, return the atmosphere to the greenhouse gas concentrations that existed for most of human history – but it wouldn’t save the oceans.

That is, the oceans would stay warmer, and more acidic, for thousands of years, and the consequences for marine life could be catastrophic.

The research, published in Nature Climate Change today delivers yet another demonstration that there is so far no feasible “technofix” that would allow humans to go on mining and drilling for coal, oil and gas (known as the “business as usual” scenario), and then geoengineer a solution when climate change becomes calamitous.

Sabine Mathesius (of the Helmholtz Centre for Ocean Research in Kiel and the Potsdam Institute for Climate Impact Research) and colleagues decided to model what could be done with an as-yet-unproven technology called carbon dioxide removal. One example would be to grow huge numbers of trees, burn them, trap the carbon dioxide, compress it and bury it somewhere. Nobody knows if this can be done, but Dr Mathesius and her fellow scientists didn’t worry about that.

They calculated that it might plausibly be possible to remove carbon dioxide from the atmosphere at the rate of 90bn tons a year. This is twice what is spilled into the air from factory chimneys and motor exhausts right now.

The scientists hypothesised a world that went on burning fossil fuels at an accelerating rate – and then adopted an as-yet-unproven high technology carbon dioxide removal technique.

“Interestingly, it turns out that after ‘business as usual’ until 2150, even taking such enormous amounts of CO2 from the atmosphere wouldn’t help the deep ocean that much - after the acidified water has been transported by large-scale ocean circulation to great depths, it is out of reach for many centuries, no matter how much CO2 is removed from the atmosphere,” said a co-author, Ken Caldeira, who is normally based at the Carnegie Institution in the US.

The oceans cover 70% of the globe. By 2500, ocean surface temperatures would have increased by 5C and the chemistry of the ocean waters would have shifted towards levels of acidity that would make it difficult for fish and shellfish to flourish. Warmer waters hold less dissolved oxygen. Ocean currents, too, would probably change.

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But while change happens in the atmosphere over tens of years, change in the ocean surface takes centuries, and in the deep oceans, millennia. So even if atmospheric temperatures were restored to pre-Industrial Revolution levels, the oceans would continue to experience climatic catastrophe.

“In the deep ocean, the chemical echo of this century’s CO2 pollution will reverberate for thousands of years,” said co-author Hans Joachim Schellnhuber, who directs the Potsdam Institute. “If we do not implement emissions reductions measures in line with the 2C target in time, we will not be able to preserve ocean life as we know it.”

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Watch Ocean Acidification in Real Time

New tools and techniques reveal global warming's evil twin at work in seawater
Brian Kahn and Climate Central Scientific American 18 Feb 15;

The depressing task of monitoring ocean acidification just got a little easier. A collection of scientists from Europe, the U.S. and India have developed a technique that could provide the first global and nearly real-time assessment of our rapidly acidifying seas.

Their findings were published in the journal Environmental Science and Technology on Monday, showing how data from satellites that measure salinity and other ocean conditions could be combined to produce a whole new way of monitoring acidification. Currently, scientists rely on ships, buoys, floats and lab tests to track the data and although these disparate pieces can construct a baseline of acidification, there are gaps in coverage.

Oceans are taking in about 90 percent of the excess heat created by human greenhouse gas emissions, but they’re also absorbing some of the carbon dioxide (CO2) itself. According to the European Space Agency, about a quarter of all human CO2 emissions are being taken in by the world’s oceans.

A complex set of chemical processes dissolves that CO2 and turns it into carbonic acid, which dissolves shells and coral, creating a cascade effect that could disrupt entire marine ecosystems. The current rate at which oceans are acidifying has been unseen in 300 million years and the consequences could be costly.

A recent study estimated $1 trillion annually in losses caused by ocean acidification by 2100, if left unmitigated. Some research has looked at “designer” corals and other creatures that could survive more acidic seas but more work needs to be done to figure out just what will thrive (or at least survive) the changing acidity.

The new monitoring techniques can help monitor hot spots such as the Bay of Bengal, the Arctic Ocean and the Caribbean, three places where ocean acidification could have major economic impacts but where little research has been done.

New monitoring efforts may come in particularly useful in the coming months, when the National Oceanic and Atmospheric Administration says there is a risk of major coral bleaching in the tropical Pacific and Indian Oceans through May, an event that may rival severe bleaching that occurred in 1998 and 2010. Some island nations in the tropical Pacific including Kiribati, Nauru and the Solomon Islands are already seeing ocean conditions that can cause bleaching.

The main culprit is ocean heat, which has been at record levels, but acidity adds to the stress on coral and makes it more susceptible to bleaching.

Satellites are not the only new tools to measure acidification’s impact. Other recent research has also suggested that listening to reefs could be a helpful, cost-effective way to monitor their health. Still others have explored other ocean metrics, such as the concentration of shell-building minerals, as a more accurate way to keep tabs on acidification’s impacts at a local level.

In the end, the choice to use ground observations or satellites isn’t an either/or decision.

“It is now time to evaluate how to make the most of satellite and in situ data to help us understand ocean acidification, and to establish where remotely sensed data can make the best contribution,” Peter Land, lead author of the new study and researcher at Plymouth Marine Laboratory, said in a press release accompanying the new study.

This article is reproduced with permission from Climate Central. The article was first published on February 11, 2015.

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UK Science chief warns on acid oceans

Roger Harrabin BBC 24 Oct 14;

The UK's chief scientist says the oceans face a serious and growing risk from man-made carbon emissions.

The oceans absorb about a third of the CO2 that’s being produced by industrial society, and this is changing the chemistry of seawater.

Sir Mark Walport warns that the acidity of the oceans has increased by about 25% since the industrial revolution, mainly thanks to manmade emissions.

CO2 reacts with the sea water to form carbonic acid.

He told BBC News: “If we carry on emitting CO2 at the same rate, ocean acidification will create substantial risks to complex marine food webs and ecosystems.”

He said the current rate of acidification is believed to be unprecedented within the last 65 million years – and may threaten fisheries in future.

The consequences of acidification are likely to be made worse by the warming of the ocean expected with climate change, a process which is also driven by CO2.

Sir Mark’s comments come as recent British research suggests the effects of acidification may be even more pervasive than previously estimated.

Until now studies have identified species with calcium-based shells as most in danger from changing chemistry.

But researchers in Exeter have found that other creatures will also be affected because as acidity increases it creates conditions for animals to take up more coastal pollutants like copper.

Shock result
The angler’s favourite bait – the humble lugworm – suffers DNA damage as a result of the extra copper. The pollutant harms their sperm, and their offspring don’t develop properly.

“It’s a bit of a shock, frankly,” said biologist Ceri Lewis from Exeter University, one of the report’s authors. “It means the effects of ocean acidification may be even more serious than we previously thought. We need to look with new eyes at things which we thought were not vulnerable.”

The lugworm study was published in Environmental Science and Technology. Another study from Dr Lewis not yet peer-reviewed suggests that sea urchins are also harmed by uptake of copper. This adds to the damage they will suffer from increasing acidity as it takes them more and more energy to calcify their shells and spines.

This is significant because sea urchins, which can live up to 100 years, are a keystone species - grazing algae off rocks that would otherwise be covered in green slime.

Dr Lewis found that at the pH expected by the end of the century, sea urchins will face damage from copper to 10% of their DNA.

Urchins are in an unfortunate group of creatures that look most likely to suffer from changing ocean chemistry.

At the bottom end of the marine animal chain, tiny creatures like plankton and coccolithophores reproduce so fast that their future offspring are likely to evolve to cope with lower pH.

At the other end of the scale are fish and crustaceans which are able to control their internal chemistry (even though some fish are affected in unexpected ways by acidification).

But the long-lived urchins are too simple to control their own body chemistry and will find it harder to adapt. They’re likely to be in trouble, along with molluscs like mussels - which provide food for predators and also perform vital services to the eco-system.

Tough, boulder corals may survive the changes, but many of the branching and table corals which provide shelter for tropical fisheries are judged unlikely to last out the century.

Slow recovery
The recent meeting of the UN’s convention on biodiversity warned that it can take many thousands of years for marine life to recover from acidification.

Dr Lewis said that it was straightforward to forecast future chemical changes to the ocean. She said predictions of future pH had drawn few of the criticisms levelled at the much more complex models of climate change.

But she warns that the biological effects of the chemical change in the oceans are harder to predict.

In her Exeter lab she is currently subjecting ill-tempered crabs to the end-of-century challenge. She plunges her hand into a seawater tank to seize the shell of one feisty specimen that does not want to be moved. It grips the water feedpipe with a vicious-looking claw.

“We think crabs should fare better with low pH than urchins do,” she tells me.

“We don't know yet how they will respond to extra availability of copper.

“Our work means we are under-estimating effects of acidification for coastal invertebrates. We are now realizing there are many indirect impacts of ocean acidification on other processes. It could be that we are facing a lot more surprises ahead.”

Dr Lewis has set herself a mission to explain the science of ocean acidification to children. Along with other ocean experts she wrote to the government urging the education department to guarantee a place for the oceans in the school science.

“It’s unacceptable that pupils can go through their entire school science career learning nothing about the oceans which cover 70% of the planet,” she says. “Ocean acidification is a fact – children should know that.”

Read more!

Scientists sound alarm over ocean acidification

AFP Yahoo News 7 Oct 14;

Ocean acidification has risen by a quarter since pre-industrial times as a result of rising carbon emissions, casting a shadow over the seas as a future source of food, scientists warned on Wednesday.

In the past two centuries, the sea's acidity level has risen 26 percent, mirroring the proportion of carbon dioxide it absorbs from the air, they said in a report to the UN Convention on Biological Diversity (CBD) meeting in South Korea.

Rising acidity will have damaging consequences for shellfish, corals and other calcium-making organisms which play a vital part in the food web, they said.

"It is now nearly inevitable that within 50 to 100 years, continued anthropogenic [man-made] carbon dioxide emissions will further increase ocean acidity to levels that will have widespread impacts... on marine organisms and ecosystems and the goods and services they provide," they said.

Acidification may already be affecting shellfish farms in the northwestern United States, they said.

The report, authored by 30 experts, was released at a conference in Pyeongchang of the CBD, an offshoot of the 1992 Rio Earth Summit.

The 102-page document, based on a review of hundreds of published studies, said the ocean's pH level was falling -- a benchmark of rising acidity -- and the consequences would be enduring.

"Recovery from a major decrease in ocean pH takes many thousands of years," it said.

The scientists pointed to a mysterious mass extinction from natural causes called the Paleo-Eocene Thermal Maximum, which occurred around 56 million years ago. The fossil record suggests it took around 100,000 years for calcifying organisms to recover from the acidification shock.

The experts sounded a special warning for tropical coral reefs, whose health is already affected by warmer seas.

The risks "are of great concern, since the livelihoods of around 400 million people depend on such habitats," they said.

The report said ocean acidification was as complex as it was important, yet there were many knowledge gaps.

It pointed to likely changes in the ecosystem as some species benefitted from the change while others were hit, and shifts in the ocean's chemistry that, in turn, may even add to warming above the surface.

"The scale and importance of these effects are not yet well understood," it warned.

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Farmers affected by mass fish deaths will be helped: Dr Maliki

Lip Kwok Wai and Shahidah Adriana Channel NewsAsia 13 Feb 14;

SINGAPORE: The authorities will help fish farmers affected by mass fish deaths recently, said Minister of State for National Development Mohamad Maliki Osman when he visited two of the affected coastal fish farms on Thursday.

The Agri-Food and Veterinary Authority of Singapore (AVA) has collected samples from fish farms that were affected by sudden fish deaths, and no marine biotoxins were detected in the samples.

AVA added that the fish deaths at some 39 fish farms along the East Johor Straits and West Johor Straits could be due to low levels of oxygen in the water and the hot weather.

It said that live fish that are in the local markets, however, are safe for consumption.

Dr Maliki assured the farmers that assistance would be provided, which include setting up aeration systems to improve water quality.

"We will look at each farm, we'll explore the amount of losses. We'll explore how best we can help them individually.

“I think it's how we can show the support -- whether it is financial support or otherwise, it really depends on what they need at this point in time, after we've done the assessment,” he said.

Loh Tee Wee, a fish farm operator, said: "The water conditions are much better today. In fact, in the last two days, the water conditions have gotten better.

“So we are very happy that the situation has improved. We have our recovery plan in place -- how we are going to move forward, continue our production and ramp up our production this year, once the coast is clear that the water quality has improved."

- CNA/nd

AVA to ‘mitigate’ farmers’ targets in light of fish deaths
Kenneth Tan Today Online 14 Feb 14;

Singapore — It has been a tale of woe for 39 fish farms along the Johor Straits, but Minister of State for National Development Maliki Osman said the Agri-Food and Veterinary Authority (AVA) stands ready to help farmers affected by one of the biggest mass fish deaths in recent years, as well as to prevent future incidents.

Farmers had in the wake of last weekend’s incident raised concerns over whether they could meet the minimum production target of 17 tonnes of fish per half-hectare space, which is part of AVA’s licensing conditions for coastal fish farms.

Speaking to reporters yesterday after visiting two farms off Changi, Dr Maliki said this year’s assessment may be mitigated. “If this year’s assessment ... is affected by such a situation, then it is only fair we will tell the farmers, ‘It’s okay, we will mitigate, we will look at how much losses you have incurred ... your productivity, the performance we measured in line with the losses you suffered’,” he added.

In all, about 160 tonnes of fish were reported to have died. Two of the farmers whom Dr Maliki visited reported suffering massive losses. Mr Teh Aik Hua of Kelong FC 117 estimated that his total losses amounted to more than S$1 million. “60 tonnes of my 70 tonnes of fish have died,” he said. Mr Teh said he hopes the AVA will be able to help his farm back on to its feet, by offering subsidies for business expenses.

Dr Maliki noted that the dead fish included species such as groupers, threadfin and golden trevally, which are the most susceptible to low levels of dissolved oxygen in the waters or a plankton bloom or both, as well as the hot weather. While this “is a very adverse situation”, the incident could help to improve farming methods and technology to prevent future recurrence, he added.

Dr Maliki also assured Singaporeans that fish on sale at markets here is safe for consumption as all the dead fish have been disposed appropriately. The AVA had collected samples from the affected farms for laboratory analysis, but no marine biotoxins were detected.

The impact to food supply will be minimal, the AVA added. In 2012, local farms produced about 5,100 tonnes of fish consumed here, but Singapore imported about 104,000 tonnes of fish from 75 sources.

Mass deaths continue at coastal fish farms
Dead fish were found at Pasir Ris Park, after more than a week of mass fish die-offs at fish farms across Singapore.
Grace Chua The Straits Times AsiaOne 14 Feb 14;

SINGAPORE - Mass die-offs at coastal fish farms across Singapore continued on Tuesday, with more dead fish washing up at Pasir Ris Park.

The mass deaths started about two weeks ago. The Agri-food and Veterinary Authority (AVA) said it had received word of fish deaths at 34 fish farms along the East Johor Strait, and at five farms along the West Johor Strait near Lim Chu Kang.

In all, some 160 tonnes of fish, or 3 per cent of the amount Singapore food-fish farms produced in 2012, were reported to have died, said the AVA. They include groupers, golden trevally and threadfin.

The AVA said it had collected samples from the affected farms for laboratory analysis and found no marine biotoxins.

The deaths, said a spokesman, could be due to low levels of dissolved oxygen or plankton bloom caused by hot weather and a neap tide, where the high tide is at its lowest.

Fish farmers said they had been working around the clock to stem their losses by doing things like setting up more aeration systems to get oxygen into the water, lowering their cage nets or reducing feeding to improve water quality.

Mr Malcolm Ong, 50, whose Metropolitan Fishery Group farms red snapper, grey mullet and tilapia under The Fish Farmer brand, said he had added extra pumps and aerators, and sent boats out to churn the water for better circulation.

"We've been very fortunate," he said, having lost only about 200kg of fish out of 10,000kg. And of his company's two fish farm sites, only the one off Pulau Ubin was affected; ano- ther off Lim Chu Kang was not.

He chalked that up to the types of fish he keeps, which could be "better able to tahan (tolerate)" poor water quality, while high-value groupers might be more delicate.

The AVA has sent a waste disposal vessel round to fish farms to collect fish carcasses, and placed a tank at Changi Point Ferry Terminal for farmers to dispose of dead fish.

"The AVA will continue to monitor the situation closely," said a spokesman.

Meanwhile, staff from the Tropical Marine Science Institute's St John's Island marine laboratory reported seeing thousands of dead wild fish off Raffles Marina at Tuas.

They had been collecting marine animals from the seabed as part of the national Comprehensive Marine Biodiversity Survey exercise, said researcher Chim Chee Kong, 36.

There have been other mass fish deaths in recent years. Last year, thousands of fish from Lim Chu Kang coastal farms died when hot dry weather cut oxygen levels in the water.

AVA support for farmers hit by mass fish deaths
Grace Chua The Straits Times So Shiok 16 Feb 14;

Fish farmers affected by the recent mass fish deaths do not have to worry about missing mandated productivity targets, said Minister of State for National Development Maliki Osman, during a visit to coastal fish farms on Thursday.

Their losses will be considered when their production is counted, and they can turn the setback into a chance to improve their farms, said Dr Maliki, who met several farmers during his visit to two farms off Changi affected by mass die-offs.

In all, 34 farms in the eastern Johor Strait and five in the west Johor Strait have lost some 160 tonnes of fish so far. The die-offs were attributed to low levels of dissolved oxygen and a plankton bloom due to hot weather and neap tides, when high tides are at their lowest, said the Agri-Food and Veterinary Authority (AVA).

While fish farms must produce 17 tonnes of fish per half hectare of farm space to keep their licences, Dr Maliki said "it's only fair that we tell the farmers it's okay, we look at how much losses you have suffered this time round, your productivity performance will be measured in line with the losses you have suffered".

The affected farms were also rearing fish more vulnerable to poor conditions, such as grouper, golden trevally and threadfin, he added. Singapore's farms produce about 6 per cent of the fish consumed here, the AVA said.

But fish in the market are safe to eat: the dead fish have all been disposed of properly, he said.

Dr Maliki, who is also South East District mayor, said the South East CDC would offer support to the families of affected Singaporean farmers and workers.

He said the authorities would also help fish farmers tap a $30 million AVA fund meant for boosting food production here, to improve aeration systems for example. But farmers must pay for equipment up front first, then submit receipts to get reimbursements.

Farmer Goh Joo Hiang, 60, who had lost up to $200,000 worth of fish, said the losses should also factor in next year's productivity targets. "Even if we bought two-inch fry now, it would take a year to raise them."

Meanwhile, the dry spell since mid-January has meant that more water has to be pumped into reservoirs.

Environment and Water Resources Minister Vivian Balakrishnan wrote in a Facebook post on Thursday that water agency PUB has been running Singapore's desalination and Newater plants "at close to full capacity". The two desalination plants here can meet up to a quarter of Singapore's water needs, with a combined output of 100 million gallons per day (mgd).

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Shellfish Growers Feeling Economic Hit as Ocean Acidifies

Julia Roberson LiveScience.com Yahoo News 28 Nov 13;

Julia Roberson directs Ocean Conservancy's ocean acidification program. She contributed this article to LiveScience's Expert Voices: Op-Ed & Insights.

Numerous studies have revealed the effects of changing ocean chemistry on marine life, and many of the findings are disturbing. However, as Katherine Gammon reported in her Oct. 2012 LiveScience article "Oysters' Future Imperiled as Oceans Acidify," the harmful effects of acidification on bivalve species such as oysters, clams and mussels are happening now, and have been happening for a while.

A few years ago, oyster growers operating in waters off the U.S. West Coast began experiencing devastating losses of juvenile oysters — up to 80 percent of their typical harvest — due to increasingly corrosive seawater. These oysters were not able to extract enough calcium carbonate to build their shells. Cold water is naturally low in calcium carbonate, so the effects of more acidic seawater have been documented first in the Pacific Ocean. The effects of acidification have also recently been felt by Maine clammers on the U.S. East Coast, who are reporting weaker shells, due, in part, to more acidic waters.

The good news is states are beginning to take action to help people who earn their living in the shellfish business. When West Coast growers suffered a devastating harvest loss, funding was made available to develop monitoring systems that enabled these businesses to tackle acidification. In late August 2013, California announced a West Coast science panel that builds on the efforts of Washington State to respond to ocean acidification. In June 2013, the Maine legislature passed a resolution identifying acidification as a major threat to Maine's economy and culture.

And last month, the XPRIZE Foundation announced its next major competition, the Wendy Schmidt Global Ocean Health XPRIZE competition for the best ideas for better, cheaper, more accessible sensors to monitor ocean acidification. Once developed, these sensors will bolster existing efforts by U.S. states and the shellfish industry to monitor what's changing in seawater, as well as how fast it's changing.

Shellfish growers are now seeking support from national policy makers. Representatives of the Pacific and East Coast shellfish growers associations, Margaret Pilaro Barrette and Bob Rheault, together with other growers, met recently with members of the U.S. Congress and officials from President Barack Obama's administration. Barrette and Rheault described the escalating threat to shellfish and requested that Congress fully fund much-needed research under the Federal Ocean Acidification Research and Monitoring Act.

For more on the damaging effects of ocean acidification on shellfish, watch the video.

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Oceans suffer silent storm of acidification: international study

Alister Doyle PlanetArk 15 Nov 13;

Global warming is causing a silent storm in the oceans by acidifying waters at a record rate, threatening marine life from coral reefs to fish stocks, an international study showed on Thursday.

The report, by 540 experts in 37 nations, said the seas could become 170 percent more acidic by 2100 compared to levels before the Industrial Revolution. Carbon dioxide, the main greenhouse gas, can become a mild acid when mixed with water.

Acidification is combining with a warming of ocean waters, also caused by a build-up of greenhouse gases in the atmosphere, and other man-made factors such as higher pollution and overfishing, the report said.

"It is like the silent storm - you can't hear it, you can't feel it," Carol Turley, a senior scientist at the Plymouth Marine Laboratory in England, told Reuters.

The study, released on the sidelines of a meeting of almost 200 nations in Warsaw on ways to slow global warming, estimated that acidity of the oceans had already increased by 26 percent since the Industrial Revolution in the 18th and 19th centuries.

A 170 percent increase in acidity is equivalent to cutting the Ph level of the ocean, a scale of acidity and alkalinity, to 7.9 from 8.2 on a logarithmic scale. Battery acid rates about 1 and soap, an alkaline, is about 10.

CORALS, CRABS

The pace of acidification was the fastest in at least 55 million years, the scientists said. Acidification undermines the ability of everything from corals to crabs to build protective shells and has knock-on effects on the food web.

"Marine ecosystems and biodiversity are likely to change as a result of ocean acidification, with far-reaching consequences for society," according to the summary led by the International Geosphere-Biosphere Programme.

"Economic losses from declines in shellfish aquaculture and the degradation of tropical coral reefs may be substantial owing to the sensitivity of molluscs and corals to ocean acidification," it said.

And some studies have found that young clown fish, made famous by the movie "Finding Nemo", behaved as if drunk in more acidic waters, their brains apparently disoriented.

Another study found that rockfish can become more anxious.

"A normal fish will swim equally in light and dark areas in a tank ... an anxious one on high carbon dioxide spends more time in the darker side, the more protected side," said Lauren Linsmayer of the University of California, San Diego.

"If society continues on the current high emissions trajectory, cold water coral reefs, located in the deep sea, may be unsustainable and tropical coral reef erosion is likely to outpace reef building this century," the report said.

Deep cuts in emissions of greenhouse gases, from power plants, factories and cars, would limit acidification.

The Warsaw talks are working on plans for a global deal, due to be agreed in 2015, to limit climate change.

(Editing by Mark Heinrich)

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Latest review of science reveals ocean in critical state

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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