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Archive for the ‘Ocean Warning’ Category

SETH SHULMAN for Grist, part of the Guardian U.K., August 23, 2010

The ocean has been our savior.

Besides generating about two thirds of the oxygen we breathe, oceangoing phytoplankton — those floating microscopic plants that form the base of the aquatic food chain — absorb about a third of all the carbon dioxide we pump into the atmosphere. In this way, the oceans have managed to slow the buildup of heat-trapping greenhouse gases and stave off even more dramatic warming of the planet.

But John Guinotte and colleagues are discovering that the critical role of “carbon sink” comes at a potentially devastating cost for the world’s oceans: acidification.

Guinotte is a coral specialist at the Marine Conservation Biology Institute in Bellevue, Wash. The changes he sees in ocean chemistry spell trouble for the coral that he studies closely. If the acidification process continues on its current trajectory, it poses a dire threat to the whole marine ecosystem.

“What I’m really concerned about with ocean acidification is that we are facing the prospect of a crash in marine food webs.” says Guinotte. “There is no question that many of my colleagues in marine science are scared about what is happening. We know we need a more precise understanding of the changes and biological responses now under way — and we need it as quickly as possible, before it is too late to turn things around.”

Guinotte has dedicated his life to the study of coral, especially the less well understood deep-sea varieties. Growing up in rural Kansas, his only exposure to corals was through the pages of National Geographic. But that changed when he learned to scuba dive at his grandfather’s winter home in the Florida Keys. The experience, plus his interest in biology and geography, led him to Australia, where he earned his Ph.D.

Guinotte still remembers the thrill of exploring Australia’s Great Barrier Reef for the first time. “I was absolutely blown away by the abundance and diversity of coral,” he recalls. At that time, back in the late-1990s, scientists were increasingly concerned about coral bleaching caused by environmental stresses such as warming ocean temperatures. Those threats remain, Guinotte says, but ocean acidification may be an even more serious and intractable problem.

On the macro scale, Guinotte explains, the chemistry of ocean acidification is relatively clear. Based on some 25 years’ worth of measurements scientists know that oceans absorb about 22 million tons of carbon dioxide every day. The oceans are vast. But even so, the absorption of CO2 is now occurring at such an unprecedented rate that ocean chemistry is approaching a state not seen in many millions of years. Guinotte fears that many marine species might be unable to adapt quickly enough to survive these dramatic changes.

As carbon dioxide is absorbed by seawater, hydrogen ions are released. This lower the pH, making the water more acidic. Measurements indicate that Earth’s oceans are already about 30 percent more acidic than they were before the industrial revolution. As the number of hydrogen ions has risen, the number of carbonate ions available in seawater has gone down. This carbonate deficit makes life more difficult for the “marine calcifiers,” species such as coral and shellfish that use carbonate to build their skeletons and protective shells.

“Ocean water becomes increasingly corrosive to calcium carbonate,” says Guinotte. “A reduction in carbonate ions not only impedes corals’ ability to build their skeletons, but once the calcium carbonate drops below critical levels, the ocean erodes the framework they have built up previously — the reefs upon which corals live.” Even if select coral species can survive ocean acidification, Guinotte says, when the coral reefs begin to dissolve, the effects on the entire marine ecosystem are likely to be devastating.

Scientists know from the fossil record that reefs which sustained damage from high atmospheric concentrations of CO2 in the geologic past took millions of years to recover. “Given that we need to think in human time scales, it means we’re playing for keeps here,” says Guinotte. “To me, it sometimes seems like a school bus full of children heading for a cliff. Somehow we have to slow it down enough to find some real solutions.”

Because of the very clear potential for ocean acidification to effect everything from the tiniest oxygen-providing phytoplankton to the larger fish that feed in the coral reefs — or, as Guinotte has written, “from the shallowest waters to the darkest depths of the deep sea” — the threat to humankind is immense.

To figure out precisely how much acidification many varieties of coral can tolerate, and what we can do to preserve the health of the marine ecosystem, Guinotte argues for a coordinated research effort that tackles every aspect of the problem. That includes better monitoring of ocean carbon; closer tracking of calcifying organisms and more laboratory and field studies of their physiological responses to increasingly acidicity; and more detailed studies that model the threat to the marine ecosystem as a whole. Some of this work is under way, but too much of it has been conducted in piecemeal fashion. Only a more intensive, coordinated effort, says Guinotte, can provide the detail necessary for policymakers to develop strategies that protect critical species, habitats, and ecosystems.

“From the standpoint of the oceans,” Guinotte says, “there is no escaping the fact that we are going to need major reductions in our CO2 emissions — something like 80 to 90 percent. When we see governments arguing about reductions of 10 to 15 percent, I think all of us in the marine science community need to say that CO2 reductions of this scale are simply not going to be sufficient. We have to get off fossil fuels.”

The fossil record shows that high CO2 concentrations have likely played a big role in mass extinctions of marine life in the past. “If marine systems start to crash, it may well be too late to stop the train,” says Guinotte. “Governments are likely to panic and make irrational decisions; international tensions could certainly heat up. These are the kinds of things that keep me awake at night. I continue to hope we can get it turned around. But it will take political will, and so far, that has been in short supply.”

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JULIETTE JOWIT, Guardian UK, July 28, 2010

Phytoplankton might be too small to see with the naked eye, but they are the foundations of the ocean food chain, ultimately capturing the energy that sustains the seas’ great beasts such as whales.

A new study though has raised the alarm about fundamental changes to life underwater. It warns that populations of these microscopic organisms have plummeted in the last century, and the rate of loss has increased in recent years.

The reduction – averaging about 1% per year – is related to increasing sea surface temperatures, says the paper, published tomorrow in the journal Nature.

The decline of these tiny plankton will have impacted nearly all sea creatures and will also have affected fish stocks.

Phytoplankton provide food – by capturing energy from the sun – and recycle nutrients, and because they account for approximately half of all organic matter on earth they are hugely important as a means of absorbing carbon.

“This decline will need to be considered in future studies of marine ecosystems, geochemical cycling, ocean circulation and fisheries,” add the paper’s authors, from Dalhousie university in Nova Scotia, Canada.

The researchers looked at measurements of ocean transparency and tested for concentrations of chlorophyll, which gives large numbers of phytoplankton a distinctive green sheen. They said that although there were variations in some areas due to regional climate and coastal run-off, the long-term global decline was “unequivocal”.

The Nature article comes as climate scientists published what they said today was the “best ever” collection of evidence for global warming, including temperature over land, at sea and in the higher atmosphere, along with records of humidity, sea-level rise, and melting ice.

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ScienceDaily, June 19, 2010

The first comprehensive synthesis on the effects of climate change on the world’s oceans has found they are now changing at a rate not seen for several million years.

In an article published June 18 in Science magazine, scientists reveal the growing atmospheric concentrations of man-made greenhouse gases are driving irreversible and dramatic changes to the way the ocean functions, with potentially dire impacts for hundreds of millions of people across the planet.

The findings of the report emerged from a synthesis of recent research on the world’s oceans, carried out by two of the world’s leading marine scientists, one from The University of Queensland in Australia, and one from The University of North Carolina at Chapel Hill, in the USA.

Professor Ove Hoegh-Guldberg, lead author of the report and Director of The University of Queensland’s Global Change Institute, says the findings have enormous implications for mankind, particularly if the trend continues.

He said that the Earth’s ocean, which produces half of the oxygen we breathe and absorbs 30% of human-generated CO2, is equivalent to its heart and lungs. “Quite plainly, the Earth cannot do without its ocean. This study, however, shows worrying signs of ill health.

“It’s as if the Earth has been smoking two packs of cigarettes a day!”

He went on to say, “We are entering a period in which the very ocean services upon which humanity depends are undergoing massive change and in some cases beginning to fail,” says Prof. Hoegh-Guldberg. “Further degradation will continue to create enormous challenges and costs for societies worldwide.”

He warned that we may soon see “sudden, unexpected changes that have serious ramifications for the overall well-being of humans,” including the capacity of the planet to support people. “This is further evidence that we are well on the way to the next great extinction event.”

The “fundamental and comprehensive” changes to marine life identified in the report include rapidly warming and acidifying oceans, changes in water circulation and expansion of dead zones within the ocean depths.

These are driving major changes in marine ecosystems: less abundant coral reefs, sea grasses and mangroves (important fish nurseries); fewer, smaller fish; a breakdown in food chains; changes in the distribution of marine life; and more frequent diseases and pests among marine organisms.

Report co-author, Dr John F. Bruno, an Associate Professor at The University of North Carolina, says greenhouse gas emissions are modifying many physical and geochemical aspects of the planet’s oceans, in ways “unprecedented in nearly a million years.” “This is causing fundamental and comprehensive changes to the way marine ecosystems function,” Dr Bruno said.

“We are becoming increasingly certain that the world’s marine ecosystems are approaching tipping points. These tipping points are where change accelerates and causes unrelated impacts on other systems, the results of which we really have no power or model to foresee.”

The authors conclude: “These challenges underscore the urgency with which world leaders must act to limit further growth of greenhouse gases and thereby reduce the risk of these events occurring. Ignoring the science is not an option.”

In their study, the researchers sought to address a gap in previous studies that have often overlooked the affects of climate change on marine ecosystems, due to the fact that they are complex and can be logistically difficult to study.

According to leading US marine scientist, the University of Maine’s School of Marine Services Professor Robert S. Steneck, the study provides a valuable indicator of the ecological risk posed by climate change, particularly to coastal regions.

“While past studies have largely focused on single global threats such as ‘global warming’, Hoegh-Guldberg and Bruno make a compelling case for the cumulative impacts of multiple planet-scale threats,” Prof. Steneck said.

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Editor’s Note: In late December 2009, the sea lions at Pier 39 in San Francisco vacated their home on the floating piers. This article may shed some light on what’s happening on the SF coast and the reasons for their leaving.  Like many others, we wonder where they went and for what reasons.

PETER FIMRITE, San Francisco Chronicle, September 22, 2009

By Bierstadt AlbertA humpback whale that suddenly rose out of the water and splashed down near the Farallon Islands provided a research vessel full of scientists with a surprising bonanza of research data.

“Whale poop!” shouted several researchers in unison, as biologists scrambled to collect the floating reddish specimens Saturday as part of a comprehensive study of the ocean’s ecology off the Northern California coast.

The color of the whale excrement meant that the huge creature had been feeding mostly on a tiny shrimp-like crustacean called krill instead of fish and anchovies, its preferred food in recent decades. It is a change in diet that several bird species at the Farallon National Wildlife Refuge are unable to make, according to researchers in a joint ocean survey by the Cordell Bank National Marine Sanctuary, the Gulf of the Farallones National Marine Sanctuary and PRBO Conservation Science.

As a result, colonies of fish-eating cormorants, seagulls and murres failed to breed this year on the Farallon Islands. Over the past few months, dozens of dead birds and even sea lions have been found on local beaches.

Anchovies have disappeared, and scientists don’t know why. The researchers on the vessel believe that, in their absence, birds and mammals like humpback whales that eat krill are thriving while the ones that are eating only fish are in trouble, and the whale excrement served as evidence.

“We’ve had an extraordinary number of dead animals,” said Jan Roletto, the research coordinator for the Gulf of the Farallones National Marine Sanctuary. “It seems to be that the animals that suffered the most were the animals that forage on anchovies.”

Brandt’s cormorants, a black bird with white plumes that can dive as deep as 300 feet for its prey, did not produce any chicks this year on the Farallones or on Alcatraz. That’s compared with 15,000 chicks in 2007.

Breeding fails

For the anchovy-loving bird, it was the first complete breeding failure in 40 years during a year without El Niño conditions so far, according to scientists at PRBO, formerly known as the Point Reyes Bird Observatory.

Western gulls and common murres produced about one-seventh of the number of chicks they normally hatch. Researchers on the Farallones reported an increase in predation on the chicks that were produced, mainly because the parents were too far away looking for food.

Beachgoers probably noticed the death toll. Six to eight times the normal number of dead cormorants and sea lions were found on Bay Area beaches in May, June and July, according to researchers. The death toll in each case involves birds and marine mammals that prey on anchovies and other fish.

The deaths and breeding failures are all the more troubling because there appears to be plenty of krill, rockfish and other prey species to feed the seagoing birds and mammals.

Jaime Jahncke, the director of marine ecology for PRBO, said common murres had previous breeding failures in 1982-83 and in 1991-92, but both times the problems were linked to El Niño, a weather condition associated with warmer ocean temperatures and atmospheric conditions that cause heavy storms. Although forecasters say an El Niño is forming in the tropics, it has not yet hit California, Jahncke said.

No explanation

“I don’t know what it means, but it’s not good,” Jahncke said. “There are a lot of changes happening, and none of them have a clear explanation.”

Seagoing birds and mammals near the Farallon Islands depend on krill, anchovies and other prey that are attracted to conditions produced when cold, deep ocean currents bounce off the underwater outcropping called the Cordell Bank, forcing nutrients upward. The nutrients are most abundant during the transition from winter to spring.

Spring arrives an average of 20 days earlier than it did in 1970, Jahncke said. There has also been an increase in the strength of the upwellings over the past two decades, he said.

Apart from the lack of anchovies, that is probably a good thing.

The team of scientists on the boat spotted several blue whales before the humpback put on its show.

The abundance of blue whales, which feed almost exclusively on krill, and the evidence provided by the humpback made it clear that there is plenty of krill in the ocean.

“Whales primarily over the last decade have been feeding on fish,” said Lisa Etherington, the research coordinator for the Cordell Bank National Marine Sanctuary. “The last couple of years they’ve been feeding on krill. We don’t know why.”

Wild fluctuations

Jahncke said salmon smolt also feed on krill, a fact that may or may not help the beleaguered Central Coast chinook. The Cassin’s auklet, a small, chunky seabird that feeds on krill, had above-average nesting success this year.

But wild fluctuations are now almost normal, according to the researchers, who are concerned that the El Niño predicted for next year will cause a further decline in the numbers of birds.

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Fire Earth, December 28, 2009

Photo by Sally & Doug Morrison

Image by Sally & Doug Morrison

About 30 pilot whales died after they became stranded on Coromandel peninsula yesterday and will be buried by the local Maori.

Meanwhile, up to 120 long-finned pilot whales, both calves and adults, were found dead  at the Farewell Spit on Boxing Day.

“More offshore wells have been drilled in the last two years than the rest of the decade combined: 35 on and offshore wells were drilled between January 2008 and July 2009 alone,” said a report.

Each year about 2.5 million tourists visit New Zealand, straining its fragile ecosystems to the breaking point, creating a massive litany of different types of pollution, including noise.

Mendo Coast Current wrote: “Studies show that these cetaceans, which once communicated over thousands of miles to forage and mate, are losing touch with each other, the experts said at a U.N. wildlife conference in Rome.”

“The sound of a seismic test, used to locate hydrocarbons beneath the seabed, can spread 1,800 miles under water, said Veronica Frank, an official with the International Fund for Animal Welfare. A study by her group found that the blue whale, which used to communicate across entire oceans, has lost 90% of its range over the past 40 years.”

Environmental experts are studying numerous cases of beached whales and dolphins that are believed to have been caused by sound pollution, according to Simmonds.

Just two weeks ago at least five whales died after nine were beached in Mediterranean off the southern coast off Italy, an unusual place for whales to beach themselves.

‘A massive beaching is extremely rare in the Mediterranean,’ biologist Maurizio Wurtz at the University of Genoa said.

Noise pollution from seismic surveys for oil and gas as well as naval activities are believed to have confused whales by interfering  with their communication, thus leaving them stranded and ultimately dead,  many  Conservationists and biologists say.

The International Fund for Animal Welfare (IFAW) says man-made ocean noise inhibits cetaceans’ communication and disrupts their feeding.

The level of ocean noise in some regions is doubling each decade, according to IFAW.  “Humanity is literally drowning out marine mammals.”

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SAM WATERSON, Special to CNN, November 2, 2009

CNN Editor’s Note: Sam Waterston is an award-winning stage, film and television actor who is best known for his long-running role as prosecutor Jack McCoy on “Law & Order.” He is a member of the board of directors of Oceana, a nonprofit organization that seeks to protect the world’s oceans by opposing overfishing and pollution.

t1larg.waterston.courtesyAs a native New Englander, I know full and well how much we depend on the oceans. They have often been a solution for our problems.

They’ve been a highway for goods and people, connecting us to the world, and a barrier against foreign invasion, protecting us from the world; a source of food and wealth, going back to our earliest beginnings, when whale oil lit our houses and when cod were so plentiful that huge specimens were commonly stacked like cordwood on our docks and wharves, and still there were so many that you could almost walk on their backs across some harbors.

Until the recent unrelenting hammering by our technologically impressive, very efficient, very destructive commercial fishing fleets, the seas have seemed an inexhaustible cornucopia of sea life for our sustenance, delight and wonder.

Now, science tells us the global wild fish catch is, for the first time in history, declining. Fortunately, we also know what steps our governments need to take to reverse this trend — steps that can again return our seas to abundance.

But, along with the ravages of industrial-scale fishing, there is another even more troubling story to tell about our oceans. For centuries, our oceans have been an uncomplaining dump. They’ve absorbed our waste — from manufacturing, power generation, and oil spills, and our nuclear waste, our trash, and our sewage.

And carbon. For the last 250 years, the oceans have absorbed 30% of the carbon dioxide we put into the atmosphere through the burning of fossil fuels and deforestation, moderating and masking its global impact. They take in 11 billion metric tons of carbon dioxide per year. Each year, the amount we release grows another 3%.

What happens to the carbon dioxide absorbed by the seas is something that you should understand if you love seafood or care about the millions of fishing jobs vital to coastal towns.

Carbon dioxide combines with seawater to create carbonic acid, raising the acidity of that vast solution and reducing the amount of available carbonate. And that is serious mischief for all kinds of sea life, from corals and pteropods, continuing on through shellfish, clams, oysters, lobsters, mussels and so on, which need carbonate to make the structures that support them.

A chain reaction begins. Even creatures whose own structural parts might better survive a decrease in available carbonate in sea water depend to one degree or another on critters with higher sensitivity. Whales and salmon eat pteropods for dinner. The very tasty and much-prized Alaskan pink salmon makes pteropods 45% of its diet.

Many kinds of fish need corals for habitat. And corals aren’t just tropical — the colder the water they live in, the more vulnerable they are to changes in the availability of carbonate.

The current acidification level hasn’t been seen for at least 800,000 years, and acidification is coming on 100 times faster than at any point for hundreds of thousands for years. The levels are alarming. The rate of change makes them even scarier, because it so restricts the ability of sea creatures to adapt.

In contrast to the debate that continues about the causal relationship between this or that weather event and human activity, there is no debate about the source of ocean acidification. The change in the chemistry of the ocean is a man-made event, plain and simple, and the consequences of its continuing rise in acidity will belong squarely to us.

It will make for some uncomfortable moments around the dinner table when our children and grandchildren ask, “What did you do in the [climate] war, Daddy?” If we don’t recognize the ocean’s warning, the first cataclysm from man-made carbon dioxide emissions that will get our attention will be the collapse of the oceans.

If we do recognize the warning, the oceans are ready to be a solution. Power in the tides and waves is there to tap. Offshore wind power is a technology that’s ready to go right now, near the great population centers on our coasts, where it’s most needed.

For 800,000 years, the seas were a stable solution, a hospitable solution for all sorts of creatures to live in, and a generous solution to all sorts of human problems, from food supply to waste disposal. We must not make them inhospitable, for people or for the 80% of life on the planet that lives in them.

Carbon dioxide in the sea is the front line of climate carbon addiction. Reverse the trend toward ocean acidification, and we will also have made a giant stride in addressing the effects of climate change. The sea is warning us to change course and calling us to seize enormous opportunities. Now.

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