'Fish Technology' Draws Renewable Energy From Slow Water Currents; 'Vortex Induced Vibrations'

Underwatertimes.com News ServiceNovember 22, 2008 16:33 EST

Anne Arbor, Michigan -- Slow-moving ocean and river currents could be a new, reliable and affordable alternative energy source. A University of Michigan engineer has made a machine that works like a fish to turn potentially destructive vibrations in fluid flows into clean, renewable power.
The machine is called VIVACE. A paper on it is published in the current issue of the quarterly Journal of Offshore Mechanics and Arctic Engineering.
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VIVACE is the first known device that could harness energy from most of the water currents around the globe because it works in flows moving slower than 2 knots (about 2 miles per hour.) Most of the Earth's currents are slower than 3 knots. Turbines and water mills need an average of 5 or 6 knots to operate efficiently.
VIVACE stands for Vortex Induced Vibrations for Aquatic Clean Energy. It doesn't depend on waves, tides, turbines or dams. It's a unique hydrokinetic energy system that relies on "vortex induced vibrations."
Vortex induced vibrations are undulations that a rounded or cylinder-shaped object makes in a flow of fluid, which can be air or water. The presence of the object puts kinks in the current's speed as it skims by. This causes eddies, or vortices, to form in a pattern on opposite sides of the object. The vortices push and pull the object up and down or left and right, perpendicular to the current.
These vibrations in wind toppled the Tacoma Narrows bridge in Washington in 1940 and the Ferrybridge power station cooling towers in England in 1965. In water, the vibrations regularly damage docks, oil rigs and coastal buildings.
"For the past 25 years, engineers---myself included---have been trying to suppress vortex induced vibrations. But now at Michigan we're doing the opposite. We enhance the vibrations and harness this powerful and destructive force in nature," said VIVACE developer Michael Bernitsas, a professor in the U-M Department of Naval Architecture and Marine Engineering.
Fish have long known how to put the vortices that cause these vibrations to good use. "VIVACE copies aspects of fish technology," Bernitsas said. "Fish curve their bodies to glide between the vortices shed by the bodies of the fish in front of them. Their muscle power alone could not propel them through the water at the speed they go, so they ride in each other's wake."
This generation of Bernitsas' machine looks nothing like a fish, though he says future versions will have the equivalent of a tail and surface roughness a kin to scales. The working prototype in his lab is just one sleek cylinder attached to springs. The cylinder hangs horizontally across the flow of water in a tractor-trailer-sized tank in his marine renewable energy laboratory. The water in the tank flows at 1.5 knots.
Here's how VIVACE works: The very presence of the cylinder in the 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.
Just a few cylinders might be enough to power an anchored ship, or a lighthouse, Bernitsas says. These cylinders could be stacked in a short ladder. The professor estimates that array of VIVACE converters the size of a running track and about two stories high could power about 100,000 houses. Such an array could rest on a river bed or it could dangle, suspended in the water. But it would all be under the surface.
Because the oscillations of VIVACE would be slow, it is theorized that the system would not harm marine life like dams and water turbines can.
Bernitsas says VIVACE energy would cost about 5.5 cents per kilowatt hour. Wind energy costs 6.9 cents a kilowatt hour. Nuclear costs 4.6, and solar power costs between 16 and 48 cents per kilowatt hour depending on the location.
"There won't be one solution for the world's energy needs," Bernitsas said. "But if we could harness 0.1 percent of the energy in the ocean, we could support the energy needs of 15 billion people."
The researchers recently completed a feasibility study that found the device could draw power from the Detroit River. They are working to deploy one for a pilot project there within the 18 months.

Commission: Europe's Seas and Coasts Under Threat from Climate Change and Pollution

Underwatertimes.com News ServiceMarch 22, 2007 11:54 EST






Brussels, Belgium -- Protecting the delicate ecosystem of Europe's seas and coastal regions was the subject of a recent hearing in Parliament. A Commission Green paper last year identified the threat to Europe's coast of rising sea levels, pollution and over fishing. This is not a small problem - the EU has a coastline longer than Africa and the EU's sea area (territorial waters of members) is larger than its land mass. The hearing on 20 March brought together MEPs, experts and the EU's Fisheries Commissioner.
Emissions trading for ships
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The 27 countries of the European Union are surrounded by four seas and two oceans. If world temperatures continue to increase this will bring rising sea levels - the impact of which could be serious for Europe. Ironically, emissions from ships (like aircraft) are not covered by the Kyoto protocol on pollution. In fact, since 1990 emissions from marine transport have risen 45%. As Jorgo Chatzimarkakis of the Liberal ALDE group remarked at the hearing "so far we have been ignoring the fact that sea transport – while it is true that it accounts for a greater amount of transported goods– emits more CO2 than air traffic". Socialist Willi Piecyk, rapporteur for the transport committee, said that "we have to consider emissions trading even for ships and vessels."
Fishermen: friend or foe of Europe's coasts?
Simon Cripps of the World Wide Fund for Nature was unequivocal on this point at the hearing. He said that commercial fisheries had put the whole ecosystem at risk and that “illegal, unreported and unregulated fishing is a significant threat to maritime biodiversity."
Peter Mortensen, a former chair of the "Social Dialogue Committee for Maritime Fisheries" said that "there are a number of paragraphs in the Green Paper that seem to be more concerned with fish than with fishermen”. He pointed out that working conditions for fishermen are very difficult and that wages are very low. In total 5 million jobs in the EU are linked to marine activity of one kind or another.
Town planning for the seas
One solution could be "Marine Spatial Planning", a kind of town planning for the seas. This approach identifies different areas and recommends what activities would be best suited for the region. It also could be used find "at risk" zones.
This could have an impact on the possible development of an anti-global warming policy of "CO2 sequestering". This involves hiding CO2 by pumping it underground. Frederico Cardicos of the Azores regional administration warned however that this could "endanger a largely unknown ecosystem".
Seán Ó'Neachtain of the Union of Europe for the Nations Group warned against strict EU legislation. He said that existing regulation was impinging on communities of sparsely populated coastal regions and that “people are not taken into the equation”.
However, no matter what approach the EU takes all speakers were agreed that without international cooperation the welfare of the world's oceans cannot be guaranteed. As Karin Roth, Parliamentary State Secretary for the German Presidency put it: "the sea is globally connected. There won’t be the division into "clean EU-sea and the non-European-Sea".
What happens next?
The hearing brought together five of Parliament's Committees: Transport, Environment, Industry, Fisheries and Regional Development. On 4-5 June the Transport Committee will consider a draft report on this subject and the Plenary session of 18-21 June will vote on the report if it is ready. The Commission's consultation with interested parties is open until the end of June. Before the end of 2007 the Commission will address a Communication to the Council and Parliament summarising the results of the consultation process and proposing the way forward.

Study: First Ever Evidence Of Natural Disease Resistance In Tropical Corals

Underwatertimes.com News ServiceNovember 21, 2008 18:33 EST

Researchers have found the first ever evidence of natural disease resistance in corals
Boston, Massachusetts -- In recent years, tropical coral reefs have become drastically altered by disease epidemics. In a new study published by PLoS ONE, lead author Steven V. Vollmer, assistant professor of biology at the Marine Science Center at Northeastern University, finds that acroporid corals listed on the US Endangered Species List due to epidemics of White Band Disease can recover because up to six percent of the remaining corals are naturally resistant to the disease. This is the first evidence of natural disease resistance in tropical reef corals.
The Carribean-wide mass die-offs of acroporid corals and urchins have been major contributors to the rapid decline of coral reefs. Reef-building corals have generally been susceptible to the global rise in marine diseases. As foundation species on tropical reefs, the impacts of White Band Disease (WBD) and other coral diseases have rippled throughout the ecosystem. Recuperation of these formerly dominant corals has been slow.
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Despite its extreme impacts, much about the causes and ecology of WBD remains poorly understood.
“Understanding disease resistance in these corals is a critical link to restoring populations of these once prevailing corals throughout their habitat,” said Vollmer. “Our study has shown that there are disease resistant corals, which means that these corals and thus the shallow water reefs of the Caribbean can be recovered.”
The study, titled “Natural Disease Resistance in Threatened Staghorn Corals” examines the potential for natural resistance to WBD in the staghorn coral. Using genotype information and field monitoring of WBD, the study found that six percent of staghorn coral genotypes are naturally resistant to WBD.
These resistant staghorn coral strains might explain why pockets of coral have been able to survive the WBD epidemic. Identifying, protecting and farming these disease resistant corals provides a clear avenue to recover these corals.

Beaked Whales Perform Extreme Dives To Hunt Deepwater Prey

A Cuvier's beaked whale breaches in the Ligurian Sea. (Photo courtesy of Natacha Aguilar de Soto, University of La Laguna, Spain)

ScienceDaily (Oct. 20, 2006) — A study of ten beaked whales of two poorly understood species shows their foraging dives are deeper and longer than those reported for any other air-breathing species. This extreme deep-diving behavior is of particular interest since beaked whales stranded during naval sonar exercises have been reported to have symptoms of decompression sickness. One goal of the study was to explore whether the extreme diving behavior of beaked whales puts them at a special risk from naval sonar exercises.

Scientists from the Woods Hole Oceanographic Institution (WHOI) teamed with colleagues from the University of La Laguna in Spain, the University of Aarhus in Denmark, Bluwest and the NATO Undersea Research Centre in Italy. The team studied Cuvier’s beaked whales (Ziphius cavirostris) and Blainville’s beaked whales (Mesoplodon densirostris) in Italian and Spanish waters using a non-invasive digital archival tag or D-tag developed at WHOI by one of the authors, engineer Dr. Mark Johnson. Their findings are reported in the current online issue of the Journal of Experimental Biology.
The D-tag, about the size of a sandal, has a variety of sensors to record sounds and movements, and is attached to the animals with four small suction cups using a handheld pole. It is programmed to release from the animal within a day and is recovered with help from a VHF radio beacon in the tag. The 3-6 Gbytes of audio and sensor data are then off-loaded to a computer for anaylsis.
Dr. Peter Tyack, a senior scientist in the WHOI Biology Department and lead author of the study, says they found some similarities with the much better studied sperm whales and elephant seals, but also some major differences. “These two beaked whale species make long, very deep dives to find food, and then make shallow dives and rest near the surface. By contrast, sperm whales and elephant seals can make a series of deep dives without the need for prolonged intervals between deep dives. We think that beaked whales return to the surface after deep dives with an oxygen debt and need to recover before their next deep dive."
Tyack said the team's analysis suggests that the normal deep diving behavior of beaked whales does not pose a decompression risk. "Rather, it appears that their greatest risk of decompression sickness would stem from an atypical behavioral response involving repeated dives at depths between 30 and 80 meters (roughly100 to 250 feet)," Tyack said. "The reason for this is that once the lungs have collapsed under pressure, gas does not diffuse from the lungs into the blood. Lung collapse is thought to occur shallower than 100 meters (330 feet), so deeper parts of the dive do not increase the risk of decompression problems. However, if beaked whales responded to sonars with repeated dives to near 50 meters (165 feet), this could pose a risk.”
The Cuvier’s beaked whales were tagged in June 2003 and 2004 in the Ligurian Sea off Italy, while the Blainville’s beaked whales were tagged in October 2003 and 2004 off the island of El Hierro in the Canary Islands. Both field sites were in deep water, between 700 and 2,000 meters (2,300 to 6,500 feet) with steep bottom topography. Tags were attached to seven Cuvier’s beaked whales and three Blainville’s beaked whales, and they remained attached to the whales for an average of 8 hours and 12 hours, respectively.
“Although this study was limited to ten animals, it provides the first detailed information available about the diving, acoustic, and movement behavior of two species of beaked whales,” Tyack said. “Shallow dives seem to be performed between deep dives, and both species dive very deep to hunt for prey. They seem to spend equal time ascending and descending in shallow dives, but take longer to ascend from deep dives.”
The slow ascent from deep dives is a major mystery. “Why don’t they stay longer at depth to feed, and then come up more rapidly?” Tyack said. “Avoidance of decompression problems by slow ascent, as in scuba divers, cannot account for this behavior if the lungs of these breathhold diving marine mammals are collapsed at depths greater than 100 meters (330 feet).”
Very little is known about these two species of beaked whales since they spend little time on the surface and it is difficult to tag them. The much better studied sperm whale can dive for more than one hour to depths greater than 1,200 meters (roughly 4,000 feet), but typically dives for 45 minutes to depths of 600-1,000 meters (1,968 to 3,280 feet). Elephant seals, another well known deep diver, can spend up to two hours in depths over 1,500 meters (nearly 5,000 feet), but typically dive for only 25-30 minutes to depths of about 500 meters (1,640 feet). Marine mammals seem to have adapted to the effects of diving deep and optimizing their oxygen supplies.
The Cuvier’s beaked whales dove to maximum depths of nearly 1,900 meters (about 6,230 feet) with a maximum duration of 85 minutes, while the Blainville’s beaked whales dove to a maximum depth of 1,250 meters (4,100 feet) and 57 minutes in duration. The dives near 1,900 meters constitute the deepest confirmed dives reported from any air-breathing animal. While people often focus on the maximum dives of breathhold diving animals, breathhold divers are not at a track meet and it is the average of the deep foraging dives that is more important. Regular echolocation clicks and buzzes and echoes of what appears to be prey were recorded on the tags, suggesting the whales were hunting for food on the deep dives. The average foraging dive for Cuvier’s beaked whale went to a depth of 1,070 meters (about 3,500 feet) with a duration of 58 minutes, while the Blainville’s beaked whales dove to an average depth of 835 meters (2,740 feet) and 46.5 minutes in duration. These represent the deepest and longest average dives reported for any breathhold-diving animal.
These two beaked whale species have been reported to mass strand during naval sonar exercises in the area. It is unclear how these beaked whale species respond to the sonar sounds and whether their responses cause physiological changes that increase the risk that they will strand and die. This study suggests the paradoxical result that even though beaked whales are extreme divers, their normal diving behavior does not seem to put them at greater physiological risk for sonar exposure. Rather it suggests that physiological risk would stem from a specific behavioral response to the sonars.
“No matter what the precise cause of the strandings is, we need to develop effective mitigation strategies to reduce the accidental exposure of beaked whales to bay sonar,” Tyack said. “The information in this study provides critical data to design efficient acoustic and visual detection methods for these at-risk species of marine mammals.”
Funding for the tag development was provided by a Cecil H. and Ida M. Green Technology Innovation Award at WHOI and the U.S. Office of Naval Research. Funding for field work was provided by the Strategic Environmental Research and Development Program (SERDP), the National Ocean Partnership Program, the Packard Foundation, the Canary Islands Government, and the Spanish Ministry of Defense. Fieldwork support was provided by BluWest, NATO Undersea Research Center, and the Government of El Hierro.

Ecologists Home In On How Sperm Whales Find Their Prey

ScienceDaily (May 29, 2006) — Ecologists have at last got a view of sperm whales' behaviour during their long, deep dives, thanks to the use of recently developed electronic "dtags". According to new research published in the British Ecological Society's Journal of Animal Ecology, sperm whales – like bats – use echolocation consistently to track down their prey at depth.

Working in the Atlantic, the Gulf of Mexico and the Ligurian Sea, scientists from Woods Hole Oceanographic Institution and the University of St Andrews attached acoustic recording tags to the dorsal surface of sperm whales with suction cups. The whales were then tracked acoustically with a towed hydrophone array.
The researchers used the tags to record the sounds that sperm whales produce while foraging. As sperm whales descended from the surface, they emitted a regular series of "clicks". When the whales reach the bottom of their dive, these clicks are emitted more often, eventually merging together to form "buzzes" of sound. This pattern reflects the whales homing in on cephalopods such as squid, with the buzzes reflecting the animals' final approach when detailed information on the squid's position and movement are required, the researchers believe.
Dr Stephanie Watwood and colleagues found that sperm whales produced buzzes on every deep dive they made, in all three locations, suggesting that they are highly successful at locating prey in the dark ocean depths.
The sperm whale is the world's largest deep-diving toothed whale, feeding mainly on squid, but until now little has been known about the timing of prey detection and capture during dives.
"Due to the difficulty of observing sperm whales during their long, deep dives, little has been known about their subsurface behaviour, giving rise to an array of speculations on how sperm whales find prey, including luring, touch, passive listening, echolocation and vision. Recording vocalisations of diving sperm whales presents a non-invasive opportunity to document feeding activity." says Watwood.

Scientists Discover New Life In Antarctic Deep Sea

This carnivorous moonsnail lives in the Antarctic deep sea. It can detect food from a wide distance and will moved towards it. Polyps, covering its shell, use the moonsnail as transport to food sources. (Credit: Image courtesy of British Antarctic Survey)

ScienceDaily (May 17, 2007) — Scientists have found hundreds of new marine creatures in the vast, dark deep-sea surrounding Antarctica. Carnivorous sponges, free-swimming worms, crustaceans, and molluscs living in the Weddell Sea provide new insights into the evolution of ocean life.

Reporting this week in the journal Nature, scientists describe how creatures in the deeper parts of the Southern Ocean - the source for much of the deep water in the world ocean -- are likely to be related to animals living in both the adjacent shallower waters and in other parts of the deep ocean.
A key question for scientists is whether shallow water species colonised the deep ocean or vice versa. The research findings suggest the glacial cycle of advance and retreat of ice led to an intermingling of species that originated in shallow and deep water habitats.
Lead author Professor Angelika Brandt from the Zoological Institute and Zoological Museum, University Hamburg says,
"The Antarctic deep sea is potentially the cradle of life of the global marine species. Our research results challenge suggestions that the deep sea diversity in the Southern Ocean is poor. We now have a better understanding in the evolution of the marine species and how they can adapt to changes in climate and environments."
Dr Katrin Linse, marine biologist from British Antarctic Survey, says,
"What was once thought to be a featureless abyss is in fact a dynamic, variable and biologically rich environment. Finding this extraordinary treasure trove of marine life is our first step to understanding the complex relationships between the deep ocean and distribution of marine life."
Three research expeditions, as part of the ANDEEP project (Antarctic benthic deep-sea biodiversity), onboard the German research ship Polarstern took place between 2002 and 2005. An international team from 14 research organisations investigated the seafloor landscape, its continental slope rise and changing water depths to build a picture of this little known region of the ocean. They found over 700 new species.

Sounds From the Sea Acoustical Oceanographers Record Noises in the Deep

July 1, 2006 — Manmade and natural sounds, from boat engines to rainfall, sound different below the sea surface. To study their impact of noise on marine life, scientists are submerging devices called Passive Aquatic Listeners, or PALs, at depths of up to hundreds of meters deep in oceans around the globe. PALs could also help track whales and other marine life.

What do boats, whales and rainfall sound like from underneath the surface of the sea? How does it affect everything that lives down there?
Jeffrey Nystuen, a physical and acoustical oceanographer at University of Washington in Seattle developed PALs, or Passive Aquatic Listeners.
"By listening passively to the underwater sound field, we learn a lot about the environment," Nystuen tells DBIS.
Researchers submerge PALs from 10 to hundreds of meters below the sea's surface. They record a few seconds of sound about every 10 minutes. Nystuen says: "You can listen for bubbles. You can listen for whales. You can listen for ships and sonars."
PALs have been submerged at locations around the world and are in place for one year. The recordings can help scientists measure wind speed or rainfall at sea -- and learn more about the wildlife. They can also help biologists identify when and where there are large groups of whales and other marine life.
Other scientists say the impacts of man-made sounds on the marine environment are of a concern and passive acoustic monitoring is a valuable tool.
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BACKGROUND: Physical oceanographer Jeff Nyustuen is giving scientists and managers a way to sift through and identify the sounds present in various marine ecosystems. Passive Aquatic Listeners (PALS) are devices that sink ten to thousands of meters below the water surface and are set to listen for a few seconds every few minutes. PALs can identify sounds coming from such things as ships, whales, volcanic eruptions, rainfall and breaking waves. The result is a record of all the noise and its intensity in the ocean environment, which can help biologists sort out what levels of noise go unnoticed, or can cause harm to marine mammals, for example.
HOW IT WORKS: PALs don't try to record every single sound in the ocean. That would take too much memory. Instead, Nyusten is developing software that allows the PALs to sift through the racket, identify and sort sound sources by frequencies as they are received.
ABOUT SOUND: Sound waves are pressure waves: the result of a vibrating object that creates a disturbance in the surrounding air. For instance, when the telephone rings, the ringer vibrates very quickly, sending energy radiating outward through the air. These vibrations disturb the molecules that make up the air. The air molecules push closer together as the object moves one way ý an effect known as compression -- and then create a space between themselves and the vibrating object as it moves the other way, called rarefaction. The motion disturbs the neighboring molecules in turn, creating an outward ripple effect, much like a stone cast in a quiet pond will cause waves to ripple outward from the spot where the stone hit.
WHAT'S YOUR FREQUENCY? All sound waves have wavelength and frequency. The distance between compressions determines the wavelength. Objects that vibrate very quickly create short wavelengths because there is very little space between the compressions, creating a high-pitched sound. Objects that vibrate very slowly create long wavelengths because the compressions are spaced further apart. This creates a low-pitched sound. Frequency measures how many crests, or compressions, occur within one second; the measurement of this speed of vibration is called a Hertz, and 1 Hertz is equivalent to 1 vibration per second. Pitch simply means those frequencies within the range of human hearing (from about 20 Hertz to 20,000 Hertz). The faster the rate of vibration, the higher the pitch; the slower the rate of vibration, the lower the pitch.
SOUND SENSE: Bats emit a series of ultrasonic pulses that bounce off objects in its environment. How long it takes for the sound to be reflected back to the bat indicates how close (or far) a given object might be, enabling the bat to orient itself as it flies, and to detect food. Modern sonar technology is based on the same principle. The more feedback the bat receives, in terms of incoming reflections, the more accurately it can pinpoint a given object's location That's why the rate of the ultrasonic calls increases as the bat nears its prey, climaxing into a "feeding buzz" as the bat locks in on its target and prepares to strike. In contrast, whales appear to use sounds (or "songs") to communicate, emitting a complex sequence of low moans, high squeals and clicking noises that can last as long as 30 minutes. The songs appear to be related to mating cycles.
STOP THAT RACKET: Noise cancellation tries to block the unwanted sound at its source, rather than merely trying to prevent it from entering our ears. If we add two waves together, and the peaks of one line up with the valleys of the other, they will cancel each other out. Digital signal processors (DSPs) are microelectronic devices that determine which sound wave is required to cancel the unwanted sound wave (noise). It then creates that sound and amplifies it through speakers or headphones. The end result is near silence. Most cell phones, CD players, and hearing aids now contain one or more DSP devices.
The American Astronomical Society and the Acoustical Society of America contributed to the information contained in the video portion of this report.

Underwater Earthquakes Geophysicists Discover Slippery Secret Of Weaker Underwater Earthquakes

October 1, 2007 — Seismologists investigating undersea earthquakes have found that molten rock lubricates faults. This decreases the amount of friction between sides of the fault and decreases the intensity of earthquakes. They also found that the fragmentation of fault lines along the seafloor contributes an earthquake-dampening effect

In December 2004, an underwater earthquake triggered a string of tsunamis along the Indian Ocean with devastating effects. Now, scientists have found ways nature is preventing some deep ocean earthquakes and save lives. Strong underwater earthquakes start off silent -- until their tsunami waves roar on shore, destroying property and lives.
But now, geophysicists and oceanographers have found a break in studying sea floor faults. Faults aren't one continuous line. Instead, they are broken up into sections and the edges of the faults are full of cracks as the earth's crust on both sides of the fault slides past each other.
"Large scale earthquakes don't occur on the sea faults," explains Patricia Gregg, graduate student from M.I.T. and Woods Hole Oceanographic Institution Joint Program in Oceanography in Woods Hole, Mass.
Molten rock -- or magma -- from under-sea volcanoes lubricates the fault, reducing the amount of friction that could cause another earthquake. By analyzing data collected by sea vessels, they discovered volcanic activity may be weakening fault lines. The hot rock could be serving as a geological lubricant, making the fault line more malleable. Less friction means less of a quake. "So, the scale of the earthquake is smaller because the volcanism warms up the fault line and makes it more difficult to break rocks," Gregg says.
"Our ultimate purpose is to forecast earthquakes on land because earthquakes cause so much damage and kill so many people," says Jian Lin, Ph.D., senior scientist in the Department of Geology & Geophysics at Woods Hole Oceanographic Institution.
By understanding what happens below the Earth's surface, geophysicists are hoping to be able to send a warning to those above-ground. The researchers say it is easier to study fault lines below sea level. They are simple in their geology and history. Fault lines on land have layers of history that make it harder to understand the physics of how they began.
The Incorporated Research Institutions for Seismology and the American Geophysical Union contributed to the information contained in the TV portion of this report.
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BACKGROUND: Many earthquakes in the deep ocean are much smaller in magnitude than expected. Geophysicists from the Woods Hole Oceanographic Institute (WHOI) have found new evidence that the fragmented structure of seafloor faults, along with previously unrecognized volcanic activity, may be dampening the effects of these quakes.
ABOUT THE STUDY: The WHOI scientists examined data on ocean transform faults collected by ships and satellites from 19 locations in the Atlantic, Pacific and Indian oceans, augmented with bathymetry maps. Ocean transform faults are fractures in the rock of the ocean floor along which horizontal motion occurs. They cut across the mid-ocean ridge system, a 40,000 mile long mountainous seam in the Earth's crust that marks the edges of the planet's tectonic plates. The mid-ocean ridges are like the seams on a baseball, and the transform faults are like the red stitching, lying perpendicular to the ridge. These faults help accommodate the motion of the tectonic plates, cracking at the edges as the different pieces of rocky crust slip past each other. Along some plates, new crust is formed, while along others, old crust is driven back down into the earth.
WHAT THEY FOUND: The largest quakes at mid-ocean ridges tend to occur at transform faults, yet the WHOI scientists found that earthquakes along the seafloor faults on the East Pacific Rise were not as large in magnitude, or resonating with as much energy as they ought to, considering the length of these faults. Conventional wisdom has held that transform faults should contain rocks that are colder, denser and heavier than the new crust being formed at the mid-ocean ridge. In contrast, the mid-ocean ridge should have a lower density because the crust is lighter than the underlying mantle rocks and thicker along the ridge, and the newer molten rock is less dense. But the WHOI scientists found that, surprisingly, the faults were not more dense -- rather, many fault zones seemed to have lighter rock within and beneath the faults.
WHAT'S GOING ON? The WHOI scientists believe that many of the transform fault lines on the ocean floor are not as continuous as they first appear from looking at low-resolution maps. Instead, they are fragmented into smaller pieces, making the length of any given earthquake rupture on the seafloor shorter -- so the earthquake travels less distance along the surface. It is also possible that magma (molten rock) from inside the earth is rising up beneath the faults. Molten rock is less brittle and more malleable, and could be dampening the strains and jolts as the plate crusts rub together, serving as a geological lubricant. Both phenomena appear to prevent earthquakes from spreading across the seafloor, thus reducing their magnitude and impact.
WHAT CAUSES EARTHQUAKES? An earthquake is the result of a sudden release of stored energy in the Earth's crust triggered by shifting tectonic plates. The Earth's lithosphere is an elaborate network of interconnected plates that move constantly -- far too slow for us to be aware of them, but moving, nonetheless. Occasionally they lock up at the boundaries, and this creates frictional stress. When that gets to be too large a strain, the rocks give way and break and slide along fault lines. This can give rise to a violent displacement of the Earth's crust, which we feel as vibrations or tremors as the pent-up energy is released. However, only 10% or so of the total energy is released in the seismic waves. However, the rest is converted into heat, used to crush and deform rock, or released as friction.

Rip Current Secrets Revealed Oceanographers Uncover The Physics Of Rip Currents

August 1, 2006 — Rip currents flow in very erratic patterns, not in steady courses as previously believed -- which may help explain why they can be so dangerous even for experienced swimmers. Oceanographers have discovered the behavior by tracking the motion of colored dye added to a wave pool generating rip currents.

NEWARK, Del. -- Each year, an estimated 100 people drown in ocean rip currents. A strong current can sweep even the strongest swimmer out to sea. Researchers are now making waves studying rip currents, revealing the life-saving information you need to know about these dangerous ocean currents.
There's something lurking in the ocean -- creating panic in even the best swimmers!
"It came really quick, like we went under a wave, and then the next thing we know it was just, like, pulling us out," says 18-year old Phoebe Brown. Not a shark, it's a rip current. And it can drag unsuspecting swimmers out to sea, up to eight feet per second.
Rip currents form at breaks in sandbars hidden underwater, creating a strong channel of water that pulls anything in its path far away from shore. Traditionally, oceanographers believed rip currents had a steady, uniform course. Now, new research shows the flow of water moves in an erratic pattern.
Oceanographer James Kirby, Jr, says, "Flow patterns get very, very complicated and very, very unpredictable, and we're trying to come to an understanding of what causes all that complication."
In a study at the University of Delaware in Newark, Kirby added colored dye to a wave pool generating rip currents. The dye's course is recorded as it moves through the current. The dye's movement shows an irregular rip current pattern -- making it more difficult to escape.
"It's very difficult for a swimmer once he's actually caught in the flow even to establish a sense of orientation and decide which way to swim," Kirby tells DBIS. He also says some rip currents can last for weeks and even months at a time, in the same location.
To avoid unpredictable rip currents, keep an eye out for signs of one, like broken wave patterns and discolored water. If you end up caught in a rip current...
"Number one is don't panic," says Jesse Steele, a lifeguard at Bethany Beach in Delaware. "Swim parallel to shore."
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BACKGROUND: A professor at the University of Delaware has created a comprehensive computer model that predicts the physical processes in the area from the high tide mark on shore to a depth of 10 meters, called the nearshore ocean.Wave weight, current movement and naturally occurring sediment transport, are analyzed by computers to from a computer model. The model allows weather forecasters to quickly predict dangerous surf conditions and issue immediate warnings. It can even predict some dangerous events weeks before they occur. Swimmers and life guards have more tools to identify rip currents, for example. The model would also be useful for builders designing shore properties.
WHAT ARE RIP CURRENTS? A rip current is a strong flow of water returning seaward along the shore. When wind and waves push water to the shore, the previous backwash is often pushed sideways by the oncoming waves. The backwash streams along the shoreline until it finds an exit back to the sea. The resulting rip current is usually narrow and located in trenches between sandbars, under piers, or along jetties. The current is strongest at the surface and can dampen incoming waves, which might make the area seem deceptively calm. That's one thing to look for when searching for rip currents: unusually calm waters. The color of the water may be different from the surrounding area, and the waterline will be lower on the shore near a rip current.
IT'S NOT THE UNDERTOW: Many of the deaths resulting from rip currents are wrongly attributed to an undertow. The two are related, but distinct. Rip currents occur if there's a place along the beach where the incoming waves aren't as strong, so that the escaping water goes through that weak spot. If there is no spot with weaker surf, the accumulated water flows down and under the waves and back out to sea, forming an undertow.
TIDES AND THE MOON: Rip currents are sometimes erroneously called "rip tides." They are not tides, although particularly low tides can lead to stronger rip currents. What are tides? The strength of gravity depends on the distance from the source; the closer you are, the stronger the "pull" that you feel. The moon's gravity acts on the earth, but the diameter of the earth is large enough compared to the distance of the moon that one side of our planet -- the one nearer the moon -- feels the moon's gravity much more strongly than the side further away from the moon. In effect, the earth is "stretched" by the difference in the moon's gravity across the earth, and this gives rise to the tides. That's why there are two tidal bulges on the earth, one on the near side, and one on the far side.
SAFETY TIPS: The most common advice for escaping a rip current is not to panic and try to swim against the current directly back to shore. People become exhausted very quickly and can easily drown. Instead, you should swim parallel to the beach and then let the waves bring you into shore.

Octopus Family Tree Traced Using New Molecular Evidence

Megaleledon setebos, the closest living relative of the octopuses' common ancestor. (Credit: Census of Marine Life)

ScienceDaily (Nov. 13, 2008) — Octopuses started migrating to new ocean basins more than 30 million years ago as Antarctica cooled and large ice-sheets grew.

These huge climatic events created a 'thermohaline expressway' - a northbound flow of deep cold water, providing new habitat for the animals previously confined to the sea floor around Antarctica, according to new research led by Dr Louise Allcock at Queen's School of Biological Sciences and colleagues from Cambridge University and British Antarctic Survey.
Isolated in new habitat conditions, many different species evolved. Some octopuses lost their defensive ink sacs because there was no need for the defence mechanisms in the pitch black waters more than two kilometres below the surface.
Dr Allcock, who was assisted on the study by Dr Jan Strugnell and Dr Paulo Prodöhl from Queen's, said: "It is clear from our research that climate change can have profound effects on biodiversity, with impacts even extending into habitats such as the deep oceans which you might expect would be partially protected from it. "If octopuses radiated in this way, it's likely that other fauna did so also, so we have helped explain where some of the deep-sea biodiversity comes from."
This revelation into the global distribution and diversity of deep-sea fauna, to be reported this week in the respected scientific journal Cladistics, was made possible by intensive sampling during International Polar Year expeditions.
The findings form part of the first Census of Marine Life (CoML), set to be completed in late 2010. It aims to assess and explain the diversity, distribution and abundance of marine life in the oceans, past, present and future.
The project, which began in 2000, involves more than 2,000 scientists from 82 nations.
The findings of a study funded by the National Environment Research Council and will be reported at a conference in Spain. The World Conference on Marine Biodiversity is taking place in Valencia between 11 and 15 November.

Zooplankton Populations Plunge 70 Percent in Four Decades; Alarming Marine Biologists

NaturalNews) Numbers of zooplankton, tiny organisms that form the base of the ocean's food chain, have plummeted 70 percent since the 1960s, according to numbers collected by the British Department for Environment Food and Rural Affairs (DEFRA).The data were included without further comment in a graph on page nine of DEFRA's 2008-2009 Marine Program Plan. The nonprofit organization Buglife noticed this graph, however, and began sounding the alarm."The implications for marine productivity and fisheries are mindboggling," Buglife Scottish officer Craig Macadam said. "The biomass of the seas is (or was!) enormous. This statistic must represent a very significant reduction in the number and weight of living organisms in the UK. Yet there has been no coverage as far as I can see in any British media. I think it would be a good idea for people to be more concerned about invertebrate conservation issues."Macadam noted that the entire marine food chain rests on zooplankton. A disruption in their populations is therefore expected to affect all ocean life, from fish to sea birds to whales."Big fish feed on little fish, so when there is a big decline in the bedrock of the marine food chain it spells trouble all down it," he said.According to the DEFRA chart, zooplankton levels declined steadily starting in the 1960s and had dropped a full 50 percent by 1990. Since then, there has been another 50 percent drop, for a total of a 73 percent population decrease.Buglife Director Matt Shardlow has sent a letter to DEFRA Director of Marine and Fisheries Rodney Anderson, applauding the quality of the organization's data but calling on it to take more decisive action."The disappearance of butterflies, moths, bees, riverflies and other small animals is an environmental tragedy," Shardlow wrote. "But, despite this experience, we were profoundly shocked to read that zooplankton abundance has declined by about 73 percent since 1960 and about 50 percent since 1990."This is a biodiversity disaster of enormous proportions."

Sources for this story include: news.bbc.co.uk; news.scotsman.com.

Oceans are teeming with undiscovered microbes

NaturalNews) While marine biologists knew that 98 percent of all life in the ocean is made up of single-celled organisms, scientists found that the diversity of the creatures may be more than 100 times greater than previously supposed.
Through the use of a DNA technique called 454 tag sequencing, researchers working on the International Census of Marine Microbes -- part of a 10-year plan which aims to catalogue marine species before the oceans are depleted -- found more than 20,000 kinds of microorganisms in a single liter of seawater. The water was expected to contain between 1,000 and 3,000 organisms.
Previously, molecular studies estimated that more than 500,000 kinds of marine microorganisms existed, but Dr. Mitchel Sogin, director of the Marine Biological Laboratory in Massachusetts, said these new results "blow away all previous estimates of bacterial diversity in the ocean."
While only 5,000 marine microbes have been named and formally described by scientists, Sogin said these new findings mean that there could be between 5 million and 10 million bacterial species in the world's oceans.
Scientists say these organisms are crucial to life on earth. "Microbes constitute the vast majority of marine biomass, and are the primary engines of the Earth's biosphere," Sogin said. "They are the oldest life forms, the primary catalysts of energy transformation, and fundamental to the biogeochemical cycles that shape our planetary atmosphere and environment."

Toxic pesticide TBT poisons worldwide marine wildlife; used widely on hulls of oil tankers

There is something picturesque about a ship bobbing up and down against a blue swell of waves and settling into a harbor to unload its cargo. Equally picturesque are the kinds of wildlife navigating underneath: Fish and shellfish scurrying about the colorful blooms of coral, piles of oysters and larger mammals, like whales and dolphins, swimming to and fro. This picture of the oceanic ecosystem is serene, almost quiet. Unfortunately, the reality of our modern marine ecosystem is far different.
For 40 years, oceanographers and fishermen have warned governments of certain marine technologies destroying the vast biota underwater. In the most recent case of environmental destruction, the culprit comes in the form of strong chemicals painted on the hulls of ships to protect from pests. Tributyltin oxide (TBT), an organotin compound, is the active ingredient in these marine paints. TBT prevents the growth of algae, barnacles and other marine organisms on the ship's hull, but, like most pesticides, these chemicals kill much more than just their targets.
TBT was first used in the 1960s as an antifouling biocide, but signs of its destructive properties didn't emerge until the 1970s. In both Europe and the United States, studies began to show rapid decimation of marine life in harbors and other high-traffic areas. The American mud-snails, dogwhelks, oysters and other mollusk populations were all in decline by the early 1970s. Shellfish were found suffering from impaired immune systems, shell deformities and a condition called imposex, in which male sexual organs appear on female mollusks.
Unfortunately, the link between these conditions and TBT was not immediately apparent. Only in the 1980s, using advanced analytical and technological instrumentation to measure TBT distribution, could scientists link these deformities directly to TBT levels. In 1986, one study of Plymouth Sound proved that increases of imposex strongly coincided with TBT applications. In 1989, studies found that the use of TBT paints on salmon-farming cages resulted in contamination of a Scottish sea loch, as well as higher incidence of imposex.
As the evidence mounted against TBT, governments slowly began to establish regulations. France, suffering huge losses in the oyster industry, was the first country to limit the use of TBT. In 1982, the French government placed controls on the application of TBT paints to vessels under 25 meters in length. (These small vessels usually spend most of their time around harbors where oyster populations could be severely effected). In 1987, the UK went one step further, banning all retail sale of TBT paint for smaller vessels. As usual, the United States was slowest to take action, introducing a similar ban in 1988.
Unfortunately, these restrictions and bans did not take into account sea-going vessels. While many of the shellfish populations partially recovered in harbors and bays, TBT dangers were by no means eliminated. The increase in commercial vessels, especially oil tankers and military vessels (both using unregulated amounts of TBT paint), has had measurable effects on marine ecosystems.
During the mid-1990s, a number of studies introduced new harms caused by TBT. This time, the effects of TBT were not limited to smaller marine life in harbors. Scientists found dangerous accumulations of butyltin in dolphins, tuna and sharks in the Mediterranean seas. A later study linked these levels to immune dysfunction. In 1997, a study linked high levels of TBT in the bottlenose dolphin to their abnormal rates of mortality reported on the U.S. Atlantic and Gulf coasts. Greenpeace also reported that TBT was been found in the tissues of cetaceans, seals, sea otters and water birds in a wide range of locations around the world.
Most startling, however, is evidence that dangerous amounts of TBT and its breakdown products accumulate in the bodies of sperm whales. This indicates that TBT may be widely dispersed in the marine environment, including the deep oceans where sperm whales normally live and feed.
In a recent study at Yale University, researchers found that TBT could cause hearing difficulties in whales and other mammals. Prestin, a protein essential to whale cochlear amplification (the amplification of sounds by tiny hairs) is severely affected by TBT levels. By hindering the mechanical activity of the outer hair cells, which boost incoming sound to the whales, TBT effectively cripples whales' auditory amplification and sensation. Because whales rely on their sensitive hearing apparatus for motor activity, damage to their ears could alter, if not annihilate, populations in some areas.
Current efforts are under way by Greenpeace and other marine environmental groups to push the government to restrict TBT use even further, if not outlaw the pesticide outright. Until then, marine populations will continue to be threatened by these toxic pesticides that remain perfectly legal to use on the hulls of oil tankers and other ships that traverse the oceans of our planet.

As ocean pollution mounts, "toxic slime" rises up, destroying ocean life

Tuesday, August 01, 2006 by: NaturalNewsKey concepts: Pollution, Ocean pollution and Ocean ecosystems

NaturalNews) The pollution of the world's oceans is extracting a price from ocean life and human life -- scientists say a dangerous "toxic slime" is rising up from the depths.
One such symptom is a mutated strain of a 2.7-billion-year-old cyanobacteria known as fireweed, which has stricken Moreton Bay fishermen with searing welts, and caused difficulty breathing when accidentally inhaled.
When fishermen reported the substance, it was dismissed until a sample made it to the University of Queensland. While in a drying oven, the sample released fumes toxic enough to send professors and students gasping for air.
"We know the human factor is responsible (for fireweed). We just have to figure out what it is," said William Dennison, former director of the University of Queensland botany lab.
While the ocean was long thought to be immune to humanity's influence, accumulated environmental influences -- such as over-fishing and runoff from pollutants -- have now altered the basic chemistry of the oceans and made them more supportive to primitive life. Harmful algae, similar to fireweed, have shown up off the coast of Sweden, on the Southern coast of Maui, on Florida's Gulf Coast and north of Venice. The Spanish coast is also overcrowded with jellyfish.
Advanced oceanic life forms are struggling for survival while primitive life forms -- such as algae, bacteria and jellyfish -- are starting to spread unchecked. This regression of evolution is "the rise of slime," according to Jeremy B.C. Jackson, a marine ecologist and paleontologist at Scripps Institution of Oceanography in La Jolla, Calif.
Over-fishing has started an evolutionary regression that has spun into a vicious circle. There has been a dramatic reduction in the numbers of turtles that prey on jellyfish and an overabundance of the plankton they love to eat, and this has lead some fishermen to become jellyfishermen.
"Easy money," said former shrimp fisherman Grovea Simpson of the creatures. "They get so thick you can walk on them."
Simpson cannot scrape together enough of his original catch to make a living anymore, so he catches great hauls of jellyfish, which are then shipped to China and Japan, where they are delicacies.
The historic fishing industry of California has also taken a dramatic turn. Three of the top five commercial catches are not fish, but squid, crab and sea urchins, and the still-surging numbers of jellyfish may catapult them to Western plates sooner rather than later.
University of British Columbia fisheries Scientist Daniel Pauly fears that one day "My kids will tell their children: Eat your jellyfish."
Perhaps the biggest casualties of humanity's lifestyle side effects are the coral reefs. Although they only cover 1 percent of the oceans' floors, they support nearly 25 percent of all ocean life.
Marine ecologist Brian Lapointe has been studying the effects of algae on a coral reef at Looe Key, Fl. When he recalls seeing the eroded reef -- starved of life-giving sunlight by the algae canopy, and purged of life by suffocating bacteria that thrives on sewage -- he likens it to coming home to find one's house ransacked by burglars.
"It rips my heart out," he says.

Court rules Navy cannot deploy sonar that harms marine mammals

Monday, November 06, 2006 by: Jessica FraserKey concepts: Marine life, Ocean ecosystems and Whales

NaturalNews) A federal appeals court recently rejected an attempt by the Bush administration to overturn a ruling that restricted the U.S. Navy's use of low-frequency active (LFA) sonar, according to the Natural Resources Defense Council (NRDC).
Three years ago, the NRDC won a landmark federal case that put limitations on the Navy's use of LFA sonar, which was found to pose a serious threat to whales and other marine life.
Since losing its appeal, the Navy must stick to an agreement with the NRDC that limits its testing and training using LFA sonar to an area in the northwestern Pacific Ocean.
The Navy's LFA sonar system generates intense underwater sound waves that can travel in excess of 300 miles. LFA military sonar was developed to detect submarines at great distances, but the NRDC and other activists argued that the noise it creates can seriously injure or even kill whales and other marine animals that depend on their sensitive hearing for survival.
"This ruling affirms the fact that we can safeguard marine mammals without compromising national security," said Andrew Wetzler, a senior NRDC attorney who argued the case.
The NRDC legal team is currently preparing for another legal battle with the Navy to restrict its use of mid-frequency sonar, which the group claims has caused a number of whale strandings and deaths across the world in the past year.
A federal court ruled in May that the Navy must turn over information on its use of sonar to the NRDC. According to the NRDC's "Nature's Voice" newsletter, a federal judge will decide in the upcoming months whether or not the case against mid-frequency sonar can continue.

Deep Sea Fishing Devastates Ocean Ecosystems, Destroys Fish Stocks

Sunday, July 06, 2008 by: David GutierrezKey concepts: Fishing, Ecosystems and Deep sea fishing

NaturalNews) Ecologists warn that the most destructive form of fishing is becoming more prevalent, with potentially disastrous consequences for ocean life."Industrial fisheries are now going thousands of miles, thousands of feet deep and catching things that live hundreds of years in the least protected place on Earth," said Elliott Norse, president of Marine Conservation Biology Institute. "They are roving bandits using state of the art technologies to plunder."In the practice of deep sea trawling, fishing boats drag massive, mile-deep nets across the ocean floor far from shore, snatching up anything in their path. Once a rare practice, deep sea trawling has increased in popularity as coastal fisheries are depleted and the demand for seafood continues to rise."All fisheries are gradually turning into deep-sea fisheries because they have fished themselves out of the shallow waters," says Robert Steneck, a marine ecologist at the University of Maine. "The solution is not going into the deep sea, but better managing the shallow waters, where fish live fast and die young but where the ecosystems have greater potential for resilience."Because the open sea is not claimed as the territory of any nation, few regulations on deep-sea trawling exist. Yet the deep sea is home to more biodiversity than any other ecosystem on Earth, with the possible exception of the tropical rainforests. A profusion of species found nowhere else make their homes among the canyons, ridges and mountains of the ocean bottom. Yet these unique geological features are flattened when a 15-ton trawler net collides with them, destroying the habitat of even the fish that escape capture.Deep sea species tend to be long-lived and slow-growing, meaning that they are particularly vulnerable to over-fishing. Stocks of the orange roughy, for example, were depleted by 75 percent within 20 years of when New Zealand began fishing for them.According to Rashid Sumaila of the University of British Columbia, fishing nations need to eliminate the massive subsidies that make the practice possible."It's important to nip these subsidies in the bud before more interests get barnacled around them," Sumaila said. "Eliminating them would render these fleets economically unviable."
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Geologist: 'Mini tsunami' likely along Thai coast in the next 50 years

Bangkok, Thailand -- Geologists have forecast that Thailand's Andaman coast could face a "mini tsunami" in the next 50 years, and warned that the area's "improper" land use could put local residences in real danger if a worse-case scenario occurs.
The magnitude of the wave would be 1.5-2.0 metres high - far less than the 5-12 metre tsunami on December 26, 2004, said Norwegian geologist Dr Kjeel Karlsrud, who conducted a risk study recently.
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"The next tsunami should happen within the next 50 to 100 years in Thailand if a quake with a magnitude of 8.5 on the Richter scale occurs underwater in the area of the Sumatra islands. The centre of the afflicted area would be similar to the first tsunami," Dr Karlsrud said.
The six provinces hit in 2004 and Koh Phrathong would still be the centre of the impact, he predicted.
"The most worrying issue is improper land use in those areas that might cause higher damage than it should," he said.
Worrawut Tantiwanich, director of the Department of Mineral Resources' Environmental Geology Division, said prevention measures were needed for the area even though the possibility of a second tsunami was a long way off.
"Warning systems and the improvement of land use in the areas potentially affected should start now," he said.
Among the suggested measures, he said, his authority had concluded that public parks should be built in particular areas as natural barriers to decrease the strength of a tsunami.
"Haad Patong should extend its emergency evacuation routes to 500 metres and add more such routes to the existing seven, while Baan Nam Khem should have 10 similar routes. Together with the efficient warning systems, these should be acceptable prevention measures," Worrawut said yesterday.
He spoke after a meeting with experts and officials from Asean countries on post tsunami measures.

Ocean alert 'may not have helped'

Ocean alert 'may not have helped'

Around 200,000 people died in the 26 December tsunamiThe existence of a warning system to detect the Asian tsunami may not have helped victims, an expert has said.
The tsunami's unprecedented scale meant adequate evacuation plans were unlikely to be in place, said Dr Tim Henstock of the National Oceanography Centre.
A mass inquest into 91 Britons' deaths in the 26 December disaster is on at Olympia Exhibition Centre, London.
Coroner Alison Thompson earlier said the four-day hearing could look only at when, where and how the 91 died.
Police say 149 Britons and people with close links to the UK died in the disaster.
Unprecedented
Dr Henstock told the hearing that no-one could have expected in the region an earthquake of the scale that hit, estimated at between 9.2 and 9.3 on the Richter scale.
Such a quake only happened approximately every 500 years, he said.
An early warning system does not help unless you have infrastructure and mechanisms and everyone knows what is supposed to be done
Dr Tim Henstock
Families 'seeking answers'
List of UK tsunami victims
Oxfam aid 'biggest ever' Any early warning system therefore required a "long-term commitment to the infrastructure", he said.
Dr Henstock said: "The people who knew the earthquake had happened were not in a position to do anything in terms of warning on the ground.
"An early warning system does not help unless you have infrastructure and mechanisms and everyone knows what is supposed to be done if a warning comes in."
He added: "These things do not happen very often but when they do they are very destructive and very widely felt."
'Limited scope'
Relatives at the inquest had questioned why no warnings appeared to have been issued or passed between the different countries hit by the tsunami.
Liz Jones, whose 23-year-old daughter Charlotte was killed in Thailand, said: "If my daughter had had five minutes she would have been alive today."
A survivor told the hearing: "There was not even a single phone call, no word of mouth, not even someone running along with a Tannoy system."

Coroner Alison Thompson will have limited time to focus on each caseMs Thompson, the west London coroner, earlier warned victims' relatives and friends at the hearing of her restricted remit.
"The scope of the inquiry is limited to determining and recording essential facts concerning each death - the identity of each victim, when, where and how they died," she said.
"This court is prohibited in law from looking at any other issues.
"I'm very aware that families may have concerns about other issues, for example the absence of an early warning system, the speed of the local response overseas to the disaster, or indeed the level of involvement of our consular staff overseas.
"While I fully acknowledge and respect their feelings in relation to this, I am sorry these matters cannot be examined in this court."
Several relatives of the deceased later displayed their anger at the speed of the response and the way they were informed by the British government.
'Amazing' generosity
The deaths of a German and a Swiss person will also be considered during the mass inquest.
Metropolitan Police Commander Cressida Dick, who led UK police operations related to the disaster, said 52 people not part of the inquest had been buried or cremated abroad and that six more were still listed as missing.
Peter Troy, humanitarian programmes manager at the Department for International Development (Dfid), said the total for dead or missing following the tsunami stood at 270,000.
He said the government had committed £75m to the recovery, and that the sum raised by the Disasters Emergency Committee "involved an amazing response from the public".
Mr Troy estimated that reconstruction would take two to three years to complete.
Family tributes
Under British law, an inquest must take place when a body is sent home after a death abroad if the coroner believes the deceased suffered a sudden, violent or unnatural death.
But due to the number of deaths being investigated, the time allocated to each individual will be limited.
The deaths of Lord Attenborough's granddaughter Lucy Holland, his daughter Jane Holland and her mother-in-law Audrey Holland will be among those considered.
Some relatives of those who died will also be able to have tributes they have written read out in the court.
It has emerged that the disaster prompted Oxfam International's biggest ever relief operation.
The charity's end of year 'Tsunami Accountability Report' revealed that £160m had been raised - 90% of which came from members of the public.

Green light for tsunami sensors

Green light for tsunami sensors

The warning system could save thousands of livesIndian Ocean countries meeting in Australia have decided to set up a network of seabed sensors and buoys as part of a tsunami warning system.
The sensors are sensitive enough to detect the slightest changes in water column pressure. They will transmit information to sea-level buoys.
The meeting in Perth was attended by representatives of 27 Indian Ocean countries at risk from tsunamis.
Last December's tsunami is believed to have killed more than 220,000 people.
The warning system could be fully operational by summer 2006, but a couple of dozen buoys should be in place by December this year.
"The establishment of seismic and sea-level networks for the Indian Ocean and an agreement on how to deploy those, I believe, is a significant step forward," Neville Smith, vice-chairman of Unesco's Intergovernmental Oceanographic Commission (IOC), said.
Concerns
The three-day forum, which ended on Friday, also agreed that seven warning centres would be created instead of one, as initially proposed.
Competition to host a single centre, which would have brought prestige and international funding to the country that hosted it, was fierce.
It was therefore decided the centres would be based in Australia, India, Indonesia, Malaysia and Thailand - plus Iran and Pakistan.
This is because scientists believe that a fault line in the Arabian Sea might trigger a huge tsunami there.
There is now concern that seven separate centres sending advisories to national warning centres in 25 countries might generate confusion.
"A major issue to be addressed is the protocol to be adopted to co-ordinate the multiple advisories to avoid confusion in the receiving nations," a working paper issued at the meeting warned.
The system is being established with the backing of Unesco, which formally set up the Intergovernmental Co-ordination Group for the Indian Ocean Tsunami Warning and Mitigation System (ICG) in June this year.

Tsunami reveals ancient temple sites

Tsunami reveals ancient temple sites
By Paddy Maguire BBC News, Madras

Shift from brickwork to granite slabs indicates different periodsArchaeologists say they have discovered the site of an ancient temple in the southern Indian state of Tamil Nadu.
It is the latest in a series of archaeological discoveries in the area struck by December's tsunami, which desilted large areas of the coastline.
The brick temple dates back more than 2,000 years to the late Tamil Sangam period and was discovered on the beachfront near Saluvankuppam, just north of a famous World Heritage site at Mahabalipuram.
The discovery lends more weight to growing evidence that a huge tsunami hit the east coast of India during this period, obliterating large habitations along the coastline.
Two periods
The Archaeological Survey of India (ASI) made the discovery while looking for a 9th Century Pallava temple.
We are looking at the remains of a brick temple that was destroyed by a tsunami approximately 2,200 years ago
Badrinarayanan S, rtd director,Geological Survey of India"The tsunami exposed inscriptions on a huge rock that had previously been protected as a site of importance," said T Satyamurthy of the ASI.
"These inscriptions dated back to 935 AD and said that Krishna the Third, from the Rashtrakuda Dynasty in Karnataka, had given gold to a temple to pay for keeping an eternal flame alight.
"This led us to dig further. Near the surface we found coins, pottery, stucco figurines and bronze lamps and so we knew there must be something more. Soon we discovered the remains of the 9th century Pallava temple."
As they continued to excavate they came across the earlier Sangam temple. The distinctive shift from courses of brickwork to large granite slabs indicates the different periods.
"The Pallavas just built on the brick foundations left behind after the Sangam temple was levelled. The two periods are there, clear to see," said Dr Satyamurthy.
Tsunami deposits
But it is the question of how these two temples were destroyed rather than their age that has fired the interest of the teams involved.

Layers of sea shells and debris point to previous tsunami strikesLayers of sea shells and debris in the sand show that tsunami activity had twice levelled the temple complex.
"The Pallava structure was destroyed by waves some time in the 13th Century and evidence suggests that beneath it, we are looking at the remains of a brick temple that was destroyed by a tsunami approximately 2,200 years ago," said Badrinarayanan S, a retired director of the Geological Survey of India.
Another archaeologist from the ASI, G Thirumoorthy, said: "We can see these tsunami deposits in Orissa, Andhra Pradesh and Tamil Nadu. We've found that devastation happened along about 1,200km (750 miles) of India's eastern coastline.
"The discovery of this Sangam temple will lead us to other geological sites along the coast and teach us more about the pre-Pallavan period."
Since the tsunami on 26 December, marine archaeologists have also discovered evidence of large structures on the seabed up to 1km out to sea.
They think the structures may be part of a former, legendary city of Mahabalipuram.
Myths state the city was destroyed by a flood sent by gods envious of its beauty.

Effect of DMSP and DMS on Marine Phytoplankton, Climate, and Plankton-Climate Feedback Interactions(2008)

Project Description:This project focuses on the factors that regulate seawater concentrations of dimethylsulfide (DMS), a volatile sulfur compound produced by microscopic marine algae (phytoplankton) that influence cloud formation and global climate. DMS produced by phytoplankton diffuses into the atmosphere where it is transformed by natural chemical reactions into small sulfuric acid particles, which provide nucleation sites for the formation of cloud droplets. The resulting clouds influence global temperatures by reflecting sunlight back into space, thereby lowering solar heating of the earth’s surface. Consequently, factors that regulate DMS production by marine plankton influence global temperatures and climate. DMS is produced from the enzymatic breakdown of a precursor molecule, dimethylsulfoniopropionate (DMSP), which occurs at high concentrations in many phytoplankton species. Researchers at CCFHR have found that phytoplankton produce DMSP and DMS at least partly in response to oxidative stress, including that caused by solar UV-radiation and nutrient limitation. These scientists have proposed a new conceptual model for biological regulation of global climate. They note that increased global warming increases the thermal stratification of ocean water, which in turn leads to nutrient limitation and increased exposure to solar UV for phytoplankton residing in the surface layer of the ocean. The resultant increase in DMS release to the atmosphere promotes the formation of more reflective clouds, which decrease solar heating of the ocean’s surface. These findings indicate the existence of a negative feedback loop in the global climate system which has important implications to any future warming of global climate. The research project focuses on the factors that regulate cellular DMSP concentrations and DMS release in phytoplankton. The research has both laboratory and field components. Laboratory experiments will be conducted to examine the effect of nutrient limitation on cellular DMSP concentrations and DMS production rates in marine algal cultures. The field research consists of time-series measurements the concentration of dissolved DMS, particulate and dissolved DMSP, and the activity of the DMS producing enzyme (DMSP lyase) in Gallents Channel off the CCFHR laboratory dock. Data are also being collected for environmental parameters that can influence DMS concentrations: water temperature, salinity, chlorophyll a (Chl a), the taxonomic composition of the phytoplankton community (via measurement of diagnostic algal pigments), and concentrations of nutrients. The data will be compared with previous time series data collected at the Bermuda Atlantic Time Series (BATS) station in the Sargasso Sea to determine fundamental differences in DMS behavior between coastal and oceanic environments.

Expected Outcome:This research will provide a better understanding of the physical, chemical, and biological factors that regulate DMS concentrations in surface ocean water, and resultant DMS flux to the atmosphere. It will provide a conceptual framework for elucidating large scale ocean/atmosphere biological feedback interactions that influence the earth’s climate and the structure and composition of marine phytoplankton communities. The research will be used to refine theoretical and numerical models for global climate change, and thus will help scientists and regulators to more accurately predict the rate of planetary global warming linked to increased atmospheric levels of CO2 and other greenhouse gases.

Completion Date:
9/2007
Fiscal Year: 2008
PI: Sunda, William -NOAA/NOS/NCCOS/CCFHR
Center: CCFHR
Location of Activity:
All International
NC
Stressor:
Global Warming
HABs
Ecosystem:
Coastal Ocean
Estuaries
SE US Atlantic Ocean

Rising ocean acidity slows marine fertilization

By Michael Perry
SYDNEY (Reuters) -

Rising acidification of the ocean could reduce fertilization of marine invertebrates and might eventually wipe out colonies of sea urchins, lobsters, mussels and oysters, according to a study.
Scientists knew that ocean acidification was eating away at the shells of marine animals, but the new study has found that rising acidity hindered marine sperm from swimming to and fertilizing eggs in the ocean.
Climate change and the subsequent acidification of the world's oceans will significantly reduce the successful fertilization of certain marine species by the year 2100, said the report by Australian and Swedish scientists.
"If you look at projected rates (of acidity) for the year 2100, we are finding a 25 percent reduction in fertilization," lead-scientist Jane Williamson from Macquarie University told Reuters on Friday.
"We were completely surprised because people had been looking at the effect of acidification on calcified structures of marine animals, but there was no evidence to suggest it was affecting non-calcified structures, like a sperm or an egg," she said.
The surface of the ocean absorbs up to 30 percent of the world's yearly emissions of carbon dioxide. Absorbed carbon dioxide forms a weak acid that is gradually increasing the acidity of the oceans.
The study of sea urchins around southeast Australia found a link between increased ocean acidity and a reduction in swimming speed and motility of sea urchin sperm.
The researchers measured sperm swimming speed, sperm motility, fertilization success and larval developmental success in sea urchins in normal seawater with a pH 8.1 and also in water with a pH 7.7, which is projected to be the level of acidification by 2100.

The experiment found that in water with acidity at 7.7, the sperm swam much more slowly and began failing to meet the eggs.
fertilization fell by 25 percent and in almost 26 percent of cases where eggs were fertilized they did not survive to develop into larvae, said the study published in "Current Biology".
"It is widely believed that seawater is chemically well-buffered, but these results show that the acidification process already well underway may threaten the viability of many marine species," Williamson said.
She said acidity levels of 7.7 were already occurring in patches of ocean off the west coast of the United States.
She said that when acidification rose to 7.4, which is projected by 2300, sea urchins failed to fertilize eggs and died.
"The paper has looked at the projected rates within the next 80 years, but we have actually looked at higher acidification values and we have had mortality of the animals," she said.
"What we have now is evidence that the world's marine life is far more sensitive to ocean acidification than first suspected, and that means our oceans may be very different places in the not-too-distant future," Williamson said.
(Editing by David Fogarty)

Issues: Oceans

Protecting Ocean Habitat from Bottom Trawling Halting this underwater version of strip-mining in sensitive areas can keep our oceans healthy and full of vibrant marine life.

If bottom trawling happened on land instead of at sea, someplace where we could see it and where cameras could film it, perhaps it would provoke the same sort of public outcry that strip-mining does. But unlike the raw, torn earth laid bare by strip-mining, the similar devastation of the ocean floor caused by bottom trawling is hidden beneath thousands of feet of water. In some cases, the damage could be irreparable.
Bottom trawlers drag giant weighted nets along the ocean floor, ripping up or scooping out whatever they encounter, including ancient coral forests, gardens of anemones and entire fields of sea sponges. Unwanted and undersized fish hauled up by bottom trawlers are thrown back dead or dying -- in some areas, as many as four pounds of fish are discarded for every one pound brought to market.
Today's technology is bringing bottom trawlers into areas ships couldn't reach before. Trawling nets, huge weighted bags, can be 200 feet wide and 40 feet high, weigh as much as 1,000 pounds, and can be sunk to depths of 5,000 feet or more beneath the water's surface. Heavier, stronger gear allows trawl nets to plow over rocky bottoms, destroying the underwater corals, sponges and rock structures that provide important habitat for fish. Advanced navigation technology brings trawl nets deeper and farther from shore, into areas populated with slow-growing deep-sea fish and corals, which are especially slow to recover from repeated trawling.
Bottom Trawling in International Waters
On the high seas, unregulated bottom trawlers operating in waters well off the coast are laying waste to huge swaths of the ocean floor. Seamounts -- volcanic mountains and hills that rise from the ocean floor but do not break the surface -- are being damaged by these industrial fishing practices, and the wealth of flora and fauna clustered around sea mounts is being wiped out in the process. Many rare, ancient and even unknown species -- some of which hold promise for biomedical research or are critical to undersea biodiversity -- are at risk, including:
Cold-water corals, which are as exotic and colorful as their warm-water counterparts. Red tree corals form ancient forests, stretching up to 7 feet tall and 25 feet wide, providing shelter for fish, shellfish, and sea stars. Corals on seamounts can live up to 8,000 years and tend to take branching, tree-like forms, making them particularly susceptible to trawl damage.
Sponges, which form giant fields in the deep, creating stretches of habitat up to a mile long and 50 feet high.
Fish, including orange roughy, which take decades to mature and can live for 125 years.
New species of flora and fauna tucked away on seamounts and other deep-sea habitats. Just like the creatures of the Galapagos Islands, many seamount species have evolved in isolation, resulting in unique species. Scientists studying a cluster of seamounts near New Caledonia have determined that nearly one-third of the species there have never been seen anywhere else.
Novel chemical compounds that hold promise for the treatment of cancer and other diseases after their discovery by scientists investigating the biomedical properties of deep-sea organisms.
Bottom Trawling in U.S. Waters
Closer to U.S. shores, bottom trawling can be just as destructive. Bottom trawlers have taken a huge toll on sport and commercial fish such as Pacific rockfish, a family of more than 60 species of colorful fish uniquely adapted to the rocky reefs, rugged canyons, pinnacles and kelp forests of the Pacific coast. Marketed as Pacific red snapper or as rock cod, they are popular with fishermen and diners. Once greatly abundant, several populations are now so depleted that scientists consider them at risk of extinction.
Rockfish have several characteristics that make them susceptible to overfishing, and particularly to bottom trawling. Some rockfish species live as long as 100 years, are slow to mature and may reproduce successfully only once a decade. Because different species school together, powerful trawl gear catches the vulnerable types along with the more productive, and these deep-dwelling fish cannot survive the trauma of being brought to the surface and then tossed overboard.
Solutions
As is the case in so many areas of ocean protection, the current patchwork of state, federal and international regulations is inadequate to the challenge of preserving the species and habitat near the ocean floors from bottom trawling. NRDC is helping to advance comprehensive oceans legislation on both the federal and state level that can protect and enhance the overall health of our oceans, and is also pushing for an international moratorium on unregulated bottom trawling in the high seas. In California, for example, NRDC helped pass a law restricting bottom trawling by state-managed trawl fisheries in vulnerable habitats.
Some temporary protective measures are demonstrating that there is potential for fish populations to recover. In 2002, to rebuild depressed rockfish populations, the Pacific Fishery Management Council put large ocean areas off limits to bottom trawling and other types of fishing on the ocean floor. These area closures have created a kind of refuge for depleted populations. West coast trawlers have also initiated a program to reduce the size of their fleet by buying and retiring boats of willing sellers.
On the opposite coast, the U.S. government closed several areas of New England's Georges Bank and the Mid-Atlantic to all fishing except lobster traps in an effort to shore up plummeting cod and haddock stocks. For nearly five years, more than 6,500 square miles of Georges Bank's sea floor were undisturbed, helping key fish stocks, including several of the area's haddock and yellowtail flounder stocks, to start rebounding. Other marine species benefited as well. Once-depleted scallop stocks resurged inside the closed areas, leading to a financial bonanza for the fishing industry when some of these areas were reopened for rotational scalloping (New England scallop landings have more than doubled over the last six years). In the areas still closed, scientists have identified increases in crabs, anemones, sea urchins and other invertebrates. However, New England's signature groundfish -- the cod -- continues to struggle, particularly on Georges Bank. Restoration may take decades. Maintaining closures large enough and long enough to be effective and halting fishing when discard limits are reached will be critical in restoring healthy fish populations and the livelihoods of fishermen who depend on them, as well as fully-functioning and diverse marine ecosystems.
International waters deserve protection as well. The international high seas cover half the planet's surface, yet only a handful of international fisheries management organizations have the authority to regulate bottom trawling, and few, if any, have acted to protect sensitive ecosystems. Without adequate regulation, countless species, habitats and possibly entire ecosystems may disappear before they can even be identified.
In keeping with the recommendation of more than 1,000 scientists around the world, NRDC and other environmental groups are pressing the United Nations General Assembly and international fisheries management authorities to adopt an immediate moratorium on unregulated bottom trawling in international waters until these vital, sensitive areas can be identified and enforceable regulations to protect them can be adopted.
Photos courtesy NOAA/MBARI.