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President Bush will establish three national monuments in the Pacific Ocean today in a move that will protect a vast marine ecosystem from mining, oil exploration, and commercial fishing. With the stroke of a pen this afternoon, Bush will have set aside more square miles of ocean for protection than any other political leader in history. The three new monuments, surrounding far-flung islands, reefs and atolls scattered across the Pacific, will add 195,000 square miles of protected waters to the nearly 140,000 square miles around the Northwest Hawaiian Islands that Bush protected in 2006 [Los Angeles Times]. The United States has authority over these waters because the tiny atolls and islands are U.S. territories.

The three areas are thronged with fish, sharks, coral reefs, and other forms of sea life, all of which will benefit from the new protections. Blue-water fish such as yellowfin, bigeye tuna, and marlin–all in decline–will be big winners because they breed in these waters. So will sharks, birds, turtles, and dolphins accidentally caught by the tuna long-line fleets [ScienceNOW Daily News]. One of the new national monuments also encompasses the deepest location of the earth’s crust. The Marianas Trench, which reaches depths of more than 36,000 feet in some locations, contains undersea volcanoes and hydrothermal vents around which cluster tough organisms that can withstand high temperatures and harsh chemicals. These “extremophiles” are of interest to scientists who think they signal forms that extraterrestrial life could take.

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The growth of the world’s largest coral reef system has slumped to its slowest rate in at least four centuries, according to a new report in Science [subscription required]. Researchers studying coral colonies in the Great Barrier Reef found that calcification, the process that builds the reefs, has dropped 13.3 percent since 1990. They fear the decline is indicative of a worldwide threat to coral reefs caused by rising seawater temperatures and ocean acidification. The loss of coral growth threatens food webs and may lead to “precipitous” changes in biodiversity, the authors said [Bloomberg].

The Great Barrier Reef along the northeast coast of Australia stretches more than 1,200 miles and is visible even in space. Coral reefs, delicate undersea structures resembling rocky gardens made by tiny animals called coral polyps, are important nurseries and shelters for fish and other sea life. They also protect coastlines, provide a critical source of food for millions of people, attract tourists and are potential storehouses of medicines for cancer and other diseases [Reuters]. Massive coral reefs materialize from the gradual accumulation of calcium carbonate by billions of coral polyps over thousands of years.

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Three months ago 90 rubber duckies set out on a perilous adventure, sliding down deep holes in a Greenland ice sheet that were expected to carry them eventually out to the ocean. In an experiment designed to shed light on the gradual melting of Greenland’s glaciers due to global warming, the duckies were deposited into moulins (tubular holes) in the Jakobshavn Glacier in mid-September by Alberto Behar, a robotics expert at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. The idea was that the ducks would float along the same channels that melt waters do, and wherever they emerged would reveal the path of the disappearing ice [Scientific American].

But thus far the researchers who have been eagerly awaiting news of the duckies’ arrival in the ocean have been disappointed, and they’re now putting out a loud call for sailors, fishermen, and cruise passengers to keep their eyes peeled for bobbing specks of yellow on the waves. The $2 ducks were chosen for their buoyancy and for their durability in low temperatures. Nasa is offering $100 to the first person who finds a duck. The toys are stamped with an email address and the word “reward” in three languages, including Inuit [Telegraph].

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Several new studies of ice loss at the earth’s poles paint a distressing picture of global warming’s impact on those fragile ecosystems, and one study warns that changes in the Arctic climate can have a large impact on the rest of the world. In the first study, researchers determined that more than 2 trillion tons of landlocked ice in Greenland, Alaska, and Antarctica have melted since 2003, a melting trend that researchers expect to continue. Using new satellite technology that measures changes in mass in mountain glaciers and ice sheets, NASA geophysicist Scott Luthcke concluded that the losses amounted to enough water to fill the Chesapeake Bay 21 times. “The ice tells us in a very real way how the climate is changing,” said Luthcke [CNN].

Melting of land ice, unlike sea ice, increases sea levels very slightly. Between Greenland, Antarctica and Alaska, melting land ice has raised global sea levels about one-fifth of an inch in the past five years, Luthcke said. Sea levels also rise from water expanding as it warms [AP]. The amount by which sea levels will rise as a result of global warming is still uncertain. The UN’s Intergovernmental Panel on Climate Change gives an official estimate of a seven-inch to two-foot rise by 2100, but researchers say conditions at the poles are changing too quickly for confident predictions.

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Chalk up another potential victim of global warming. A new study warns that the jumbo squid (also known as the Humboldt squid) may not fare well in the coming decades, as the oceans get warmer and absorb carbon dioxide from the atmosphere, which makes the water more acidic. Jumbo squid blood carries very little oxygen - with each cycle through its body, the oxygen can be used up entirely. This means they must “recharge” constantly, and makes the animals very dependent on what oxygen is available in the water around them. Yet, the warmer water is, the smaller the amount of oxygen it can hold [New Scientist].

What’s more, the squid’s blood cells can carry less oxygen in acidic water. Their blood-oxygen delivery system is highly sensitive to pH, so “the organisms are thought to live chronically ‘on the edge of oxygen limitation,’” the authors wrote. During the day, the squid descend to lower depths in the ocean to rest, slowing down their metabolism to deal with the lower oxygen levels there. At night, they return to well-oxygenated waters nearer the surface to feed [LiveScience]. However, if surface waters are both warmer and more acidic, the squid trying to feed at the surface will get much less oxygen, which will slow down their metabolisms. And lethargic squid are easy targets for predators like sperm whales, researchers say.

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Massive swarms of jellyfish are a growing threat to swimmers, the fishing industry, and even the nuclear power industry, a new report argues, and it’s high time for scientists to begin researching the causes of the population boom and how to reverse the trend. The new report from the National Science Foundation may tend towards sensationalism (the report is titled “Jellyfish Gone Wild!!“), but the problem is very real. The report says more than 1,000 fist-sized comb jellies can be found in a cubic yard (meter) of Black Sea water during a bloom. They eat the eggs of fish and compete with them for food, wiping out the livelihoods of fishermen, according to the report [Reuters]. A big swarm of jellies can also burst a fishing net or poison and crush a load of captured fish, the report says, and their bodies can clog boat engines.

“When jellyfish populations run wild,” the NSF jellyboffins warn, “they may jam thousands of square miles with their pulsing, gelatinous bodies.” It seems that no less than half a billion “refrigerator sized” slimy horrors weighing 450 pounds each invade the Sea of Japan daily, while Australian waters are plagued with “deadly, peanut-sized” Jellybabies of Death [The Register]. Popular tourist beaches from Spain to Alabama have been closed in recent years when swarms of stinging jellies threatened to harm bathers. As for their impact on nuclear power: The report claims that swarms of jellies sometimes clog the water intake pipes of power plants, and notes that in 1999 just such an incident forced a power plant in the Philippines to shut down, which “plunged 40 million people into darkness and started rumors of a coup d’etat.”

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While Indonesia is still rebuilding following the devastating 2004 earthquake and tsunami that killed more than 130,000 people on the island of Sumatra alone, scientists are warning that several other major earthquakes are likely to occur in the region over the next decades. A new study examined the growth records of coral reefs off the coast of Sumatra, and say they show evidence of repeated bursts of earthquakes that relieve pressure on the Sunda fault. A shock in 2007 may be the beginning of a new cycle, researchers say.

Says study coauthor Kerry Sieh: “If previous cycles are a reliable guide we can expect one or more very large west Sumatran earthquakes … within the next two decades” [Reuters]. As if to illustrate the point that the Indian Ocean is seismically active, reports are coming in that a 5.9 magnitude earthquake struck last night off the coast of Sumatra; happily, there have been no reports of casualties or damages, and authorities say there is no risk of a tsunami.

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Over 4 billion years ago the young and barren Earth was being buffeted by meteor strikes, and that violent bombardment could have created the first amino acids that then gave rise to the origin of life on the planet, a new study suggests. The hellish temperatures and pressures generated when an extraterrestrial object strikes Earth at speeds of several kilometers per second are enough to shatter and vaporize rock…. Yet part of such an immense burst of energy can trigger chemical reactions that generate complex organic substances from basic inorganic ingredients, says Takeshi Kakegawa [Science News].

Previously, researchers have suggested that organic molecules may have been created elsewhere in the universe and were brought to Earth by meteors. But the new study, in which researchers simulated the impact of meteorites in the primordial ocean, argues that the organic molecules could have been synthesized from the inorganic molecules already present on the planet when the meteorites crashed into the ocean. Other researchers have suggested similar processes for the creation of organic molecules on Earth, including lightning strikes or chemical reactions surrounding hot, volcanic vents in the deep sea.

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The oceans are getting noisier, and that’s bad news for whales, dolphins, and sea turtles who use sound to communicate and navigate, researchers declared at a United Nations wildlife conference. Rumbling ship engines, seismic surveys by oil and gas companies, and intrusive military sonars are triggering an “acoustic fog and cacophony of sounds” underwater, scaring marine animals and affecting their behavior. “There is now evidence linking loud underwater noises with some major strandings of marine mammals, especially deep diving beaked whales” [Reuters], says Mark Simmonds of the Whale and Dolphin Conservation Society.

Researchers have long worried that high-powered sonar pulses confuse whales and dolphins and may cause the animals to beach themselves. Marine mammals are turning up on the world’s beaches with tissue damage similar to that found in divers suffering from decompression sickness. The condition, known as the bends, causes gas bubbles to form in the bloodstream upon surfacing too quickly. Scientists say the use of military sonar or seismic testing may have scared the animals into diving and surfacing beyond their physical limits, Simmonds said [AP]. He points to two recent strandings as possible results of the noisy waters (although a link has not been proved): the 100 melon-headed whales that were found on a Madagascar beach, and the two dozen dolphins that got stranded in southern England.

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A marine engineer and naval architect has designed a new way of drawing energy out of slow-moving rivers and gentle tides. The researcher says the unobtrusive device, which was inspired by the way fish move through the water, could be set down on riverbeds or suspended in the ocean just about anywhere. Existing technologies which use water power, relying on the action of waves, tides or faster currents created by dams, are far more limited in where they can be used, and also cause greater obstructions when they are built in rivers or the sea. Turbines and water mills need an average current of five or six knots to operate efficiently, while most of the earth’s currents are slower than three knots [Telegraph].

Engineer Michael Bernitsas’s device is called VIVACE, which stands for Vortex Induced Vibrations for Aquatic Clean Energy. How does the technology work? A cylinder-shaped object in the water current causes alternating vortices to form above and below the cylinder. The vortices push and pull the passive cylinder up and down on its springs, creating mechanical energy. Then, the machine converts the mechanical energy into electricity [Greenbang]. Bernitsas explains that fish also create vortices as they swim, and in a large school each fish curves around the vortices left by the fish in front, using the tiny whirlpools to propel themselves forward.

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It’s a question that has fascinated scientists for decades: When sea turtles and salmon decides to give up the freedom of the open ocean and head back to their birthplaces to breed, how do they find their way back? Some species of sea turtle migrate thousands of miles across entire oceans back to their birthplaces after leaving more than 10 years earlier. And after hatching in rivers, salmon travel hundreds of miles out to sea before returning home to spawn years later [Press Association]. Now one researcher thinks he has the answer. Marine biologist Kenneth Lohmann believes that these marine animals can detect the distinctive magnetic fields of different spots and use them to navigate.

“What we’re proposing is the sea turtles and salmon, when they begin life, basically learn or imprint on the magnetic field that marks their home area,” he said. “They retain this information. And years later, when it is time for them to return, they are able to exploit this information in navigating back to their home area” [National Geographic News]. Lohman says this doesn’t contradict the existing theory that when salmon reach coastal waters, chemical scents guide them upriver to the particular stream where they were born; those olfactory cues probably have a limited range, he says, and couldn’t extend thousands of miles into the ocean to guide the salmon all the way home.

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Ocean acidification is happening at 10 to 20 times the rate predicted by existing climate models, according to an eight-year study. The rapid acidification of the oceans is linked to global warming and may be a sign that the oceans, the largest absorber of atmospheric carbon dioxide, may not be as hardy as presumed. The changes threaten disaster for marine life with shells that are easily corroded by acid. Marine biologist Nancy Knowlton said, “This is typical of so many climate studies—almost without exception things are turning out to be worse than we originally thought.” [National Geographic News].

The study was done around Takoosh Island off the coast of Washington state and represents the first detailed dataset on variations of coastal pH at a temperate latitude, where the world’s most productive fisheries are found [Times of India]. The researchers took over 24,000 measurements of ocean pH over an 8-year period. During that time, the pH of the seawater was predicted to decrease by only 0.015 points. Instead, the data showed that seawater pH dropped by 0.36 to about 8.1. “The increase in acidity we saw during our study was about the same magnitude as we expect over the course of the next century,” said study co-author Timothy Wootton [National Geographic News].

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Researchers have determined the mechanism by which the world’s simplest vision system works. A team of biologists spent a decade studying the larvae of the marine rag-worm Platynereis, a tiny creature with just two cells that respond to light and direct the worm to swim towards it. The rag-worm and other zooplankton like krill drift in the ocean’s water columns, swimming up from the depths towards the light in order to graze on marine plants called phytoplankton near the surface. This movement, called phototaxis, is the biggest biomass displacement in the world [AFP].

The rag-worm has two cells that work together as “proto-eyes”: one pigment cell and one light-sensitive cell. First, the pigment cell absorbs light and casts a shadow over the photoreceptor cell. The shape of the shadow varies according to the position of the light source. The photoreceptor cell then converts this light signal into electricity, sending it in a signal along a nerve that connects to a band of cells endowed with thin hairs, called cilia, that beat to displace water [AFP]. So although the worm sees no images, it can sense the difference between light and dark and swim in the right direction.

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The evolution of minerals on our planet has been propelled by the evolution of life on earth, a sweeping new study demonstrates. While the underlying assumption isn’t new, the study is the first to chart how the emergence of algae and then complex microorganisms gave rise to the 4,300 or so minerals that are now present on earth.

In the early days of the universe, clouds of gas and dust contained all the naturally occurring elements found in the periodic table, but most were too widely dispersed to form minerals; scientists believe there were only about a dozen minerals in the interstellar medium. According to the study, around a further 60 different minerals formed 4.5 billion years ago, as clumps of matter collided and coalesced to begin forming the Solar System. The smaller fragments congealed into larger, planet-sized bodies, where volcanism and the effects of water took the mineral count into the hundreds. The planets Mars and Venus have got this far [Nature News], and have minerals created by hot magma like quartz and zircon.

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The U.S. Supreme Court has sided with the Navy over the Pacific Ocean’s whales, declaring that the Navy can continue its military exercises using high-powered sonar, despite environmentalists’ arguments that the sonar can harm whales’ ears or cause the panicked animals to beach themselves. The court ruled, in a 5-4 decision, that national security needs override these concerns. Chief Justice John Roberts wrote the majority opinion, stating: “Of course, military interests do not always trump other considerations, and we have not held that they do. In this case, however, the proper determination of where the public interest lies does not strike us as a close question” [ABC News].

The lawsuit centered on 14 sonar exercises that the Navy wanted to conduct off the coast of Southern California to train seamen in detecting enemy submarines. In his opinion, Roberts stressed the military threat posed by modern subs. “Modern diesel-electric submarines . . . can operate almost silently, making them extremely difficult to detect and track.” America’s potential adversaries have at least 300 of these subs, he said. “The president — the commander in chief — has determined that the training with active sonar is ‘essential to the national security’” [Los Angeles Times].

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