marine science and the coast

New Study: Predators Help Stabilize Marine Fish Populations

CORVALLIS, Ore. - Predators - and not competition within a species - are the primary source of population control and regulation in marine fish, a new study concludes. Overfishing of predatory species, which "appears to be rampant worldwide," runs the serious risk of destabilizing other marine species and disrupting marine biodiversity, researchers said in a report in the professional journal Ecology.

The findings contradict some of the basic approaches of modern fish management, which assume that competition between fish within a species is much more important in regulating populations.

The research was done by Mark Hixon, a professor of zoology at Oregon State University, and Geoffrey Jones of James Cook University in Australia. They examined kelp forests and coral reefs around the world, and concluded that predators are the dominant force in regulating abundance of their prey.

"These findings are important because they show that sustaining fisheries requires the help of predators," says Hixon. "Predators act to keep the abundance of their prey from fluctuating wildly, thereby promoting stability of prey populations fished by humans. Unfortunately, predatory fishes themselves are being overfished, so the populations of their prey may also become destabilized."

Hixon and Jones reviewed a dozen studies, including several of their own, in which scientists have experimentally removed predators from reefs in the ocean and observed that the mortality of their prey is no longer regulated. In practice, they said, populations of fish species are probably controlled by a combination of factors acting together, including predation, recruitment, habitat structure, ocean conditions and sometimes competition.

The research is supportive of the new trend towards "ecosystem-based management."

"John Muir had it right a hundred years ago," Hixon said. "Muir said 'When we try to pick out anything by itself, we find it hitched to everything else in the universe.' It is time to start managing our living marine resources from this holistic perspective by conserving marine predators."

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Mark Hixon, 541-737-5364

Despite Indian Ocean Warning, Northwest Still Not Prepared for Potential Tsunami

ASTORIA, Ore. - Nearly one year has passed since the devastating Sumatra earthquake and tsunami and despite that stunning wakeup call, Pacific Northwest residents are ill-prepared and even dismissive of the danger presented by the offshore Cascadia Subduction Zone.

During the last 10,000 years, there have been at least 23 earthquakes of magnitude 8.5 or higher off the Northwest coast, scientists say, and the threat from a major event and subsequent tsunami is very real - and probably overdue.

Yet education and outreach efforts have met with mixed results that vary individual by individual, and community by community, says Patrick Corcoran, coordinator of the Oregon State University's Sea Grant Extension Coastal Storms Program.

"People tend to either be dismissive of the danger, or fatalistic about it," he said. "Both are exactly the wrong approaches to take."

During the past several months, Corcoran has begun working with coastal communities in Oregon and southwest Washington to educate them about the danger of a subduction zone earthquake and tsunamis. Scientists say the Cascadia Subduction Zone is remarkably similar to the terrain in the Indian Ocean that led to the 2004 Sumatra quake and such devastation could occur in the Pacific Northwest.

Though some education progress has been made in a general sense, Corcoran says, people still don't know enough about how earthquakes and tsunamis could directly affect them.

"If you live in tornado country, you know to get into your basement with your radio and ride it out," Corcoran said. "You do it every year. But people living along the coast for the most part have no idea if they're in the inundation zone, they have made no plans on evacuating the family, and they haven't even identified a meeting place. In short, few families have any kind of communication plan."

Though signage along the coast has improved and siren systems have been installed, too many residents are unaware of what would happen should an earthquake and tsunami strike, Corcoran says.

"The general scenario played out is that a disaster would happen at 6 p.m. with the family gathered around the dinner table," he said. "No one thinks about what to do if the kids are at school, or Mom is running errands on the other side of a river over which lies a bridge that will collapse. There is a general feeling that someone will come to the rescue. But in a full-scale disaster as we saw in New Orleans with Hurricane Katrina - that may be some time."

In his presentations, Corcoran emphasizes the difference between a subduction zone earthquake, which occurs where tectonic plates collide, and crustal quakes, which are more frequent but usually less severe. He also differentiates between a distant earthquake - near Alaska or Japan, for example - that would give Northwest residents a few hours to evacuate, and a local event that may send a 60- to 90-foot surge of water inland within 30 minutes.

Though much of the attention has focused on tsunami preparedness, Corcoran says, few people think about the potential impact of a local magnitude 9.0 earthquake.

"People should not expect emergency services following a major earthquake," Corcoran said. "Local emergency responders will be overwhelmed and it will be difficult for others to help us. First, Highway 101 will be closed in hundreds of places because of earthquake-induced landslides, bridge failures and inundation damage, and major east-west highways would likewise be closed.

"Portland and the valley, being inland, would still be affected by the earthquake and have their own problems to address," he added. "It might be a few - to several - days before rescue efforts could reach local residents at the coast."

Corcoran says it is impossible for coastal communities to totally prepare for such a nightmare scenario, yet there are some things they can do that would help. One would be to publicize the location of assembly areas where evacuees should gather after a local earthquake.

"People need to know where 'safe' is," Corcoran said. "We have lots of signs telling us where to flee from, but no information on when to stop."

Communities also can continually educate themselves about earthquakes and tsunamis, focusing on the differences between distant and local events. Siren warnings, Corcoran says, should not be a cause for panic because they signify a distant event and local residents have time - often hours - to prepare.

"People who think sirens mean that tsunamis are imminent are dangerously misinformed," Corcoran said. "These are the people who jump into their cars and may cause accidents. A major local earthquake, on the other hand, is the warning that a tsunami may hit in as little as 15 to 30 minutes."

A third thing communities can do, Corcoran says, is to encourage families to develop a communication plan. During a distant event, phone lines may be jammed, causing inconvenience and stress. Families with homes in the inundation zones may not be able to return to them.

"A pre-determined meeting place would be very useful," Corcoran said. "During a local event, families need to understand that everyone will be on their own. They need to get themselves to safety first, and do not enter an inundation zone. Call a non-local relative and let them know you're okay."

Families and individuals, Corcoran said, should follow some simple guidelines:


  • Identify the "inundation" zones in your community, so you know where high water will hit, as well as the "safe" zones where you need to get to;


  • Develop a communication plan for your family - and even friends and neighbors - that includes agreement on local meeting place, and a distant relative or friend you can call if you get separated;


  • Educate children about what to do in an earthquake and tsunami, especially if they are away from home. Know where your children are taken in an earthquake during school hours.

    "Disaster kits may be helpful, but I'd suggest learning first aid and CPR," Corcoran said. "Knowing how to use a T-shirt to make a bandage is more useful than having an emergency bag you don't know what to do with - or is under the rubble that used to be your garage. And simply buying an emergency kit can lead to complacency and a feeling that you have things covered when you do not."

    It is up to individuals to take care of themselves and their families, Corcoran said. Local authorities cannot possibly help everyone at the same time following a local event. Don't anticipate that organized help will immediately and magically appear, he added.

    "There are no nannies during a major earthquake and tsunami."

  • Story By: 

    Patrick Corcoran, 503-325-8573

    Oregon State Scientists to Deploy Underseas Listening Devices in Antarctica

    NEWPORT, Ore. - A team of scientists and educators from Oregon State University's Hatfield Marine Science Center in Newport has left for Antarctica on a research project to deploy an array of undersea hydrophones.

    These hydrophones, developed at the OSU center, will record the sounds of undersea earthquakes and volcanoes, moving ice sheets, and even the vocalizations from large baleen whales, according to Robert P. Dziak, an associate professor at the university who also works for the National Oceanic and Atmospheric Administration.

    "This new ocean-sensor technology will use cold water-capable, deep-ocean hydrophones to provide the first-ever comprehensive record of the sounds of Antarctica," Dziak said. The team will recover the hydrophones on a follow-up cruise in 2006.

    Bill Hanshumaker, a Sea Grant marine educator, is accompanying the researchers and will post progress reports online beginning Dec. 5. The team will post images, sound files and logs of the trip as part of the project, which is called "Sounds of the Southern Ocean." The cruise, a component of NOAA's Ocean Explorer program, will conclude on Dec. 13.

    Project updates will be posted on the cruise website, http://oceanexplorer.noaa.gov/explorations/05sounds/welcome.html, and on an Oregon Sea Grant website, http://seagrant.oregonstate.edu/extension/hanshumaker/ocean_explorations.html.

    The Southern Ocean surrounds Antarctica and serves as a conduit between the Atlantic, Pacific and Indian oceans. Yet because of severe climatic conditions, much of this ocean basin remains unexplored, Dziak said.

    "Polar regions play key roles in the global environment and one goal of our project is to document linkages between changes in the Antarctic ice sheet and the volcano-tectonic seafloor processes in the region," Dziak said.

    After arriving in Punta Arenas, Chile, the project team is scheduled to fly to King Sejong, a Korean research station, on the Barton Peninsula of King George Island on Dec. 3. From there, they will board a Russian research vessel, the Yuzhmorgeologiya, Dec. 6, which will take them to the Bransfield Strait for deployment and testing of the hydrophones.

    The research team also includes Haru Matsumoto, a NOAA engineer who helped develop the hydrophones and will coordinate the hydrophone installation; and Sara L. Heimlich, a NOAA marine mammal specialist, who will conduct visual and acoustic surveys of marine mammals. Both work at OSU's Hatfield Marine Science Center.

    Story By: 

    Bill Hanshumaker, 541-867-0167

    Scientists Hone in on Earthquake 'Pulses' to Help Predict Tsunami Impact

    CORVALLIS, Ore. - The magnitude 9.2 earthquake that triggered a devastating tsunami in the Indian Ocean in December of 2004 originated just off the coast of northern Sumatra, but an "energy pulse" - an area where slip on the fault was much greater - created the largest waves, some 100 miles from the epicenter.

    Seismologists have mapped these energy pulses for Sumatra and are trying to learn more about them to predict better when and where tsunamis may occur. They also hope these pulses will help them gain a more comprehensive understanding of the earthquake history of the Cascadia Subduction Zone off the Pacific Northwest Coast of the United States.

    "Understanding the nature of these pulses could be critical because it could mean the difference between 15 minutes and 30 minutes in a tsunami warning," said Chris Goldfinger, an associate professor in the College of Oceanic and Atmospheric Sciences at Oregon State University and one of the leading experts in the world on the Cascadia fault zone.

    "It seems that the largest Cascadia earthquakes have three pulses," Goldfinger added, "and core data show that more than half of the earthquakes in the Cascadia Subduction Zone are of this large type that appear to generate three rupture sequences."

    Earthquake "pulses" are releases of energy from areas of high slip along the main fault. When a subduction zone earthquake occurs, the tectonic plates that have locked for centuries suddenly release. An area of ocean floor that may be as wide as 50 miles, and as long as 500 to 600 miles, can suddenly snap back, causing a massive tsunami. As that energy radiates down the fault, it is concentrated in certain areas, Goldfinger said. The severity of the tsunami in any locality depends on how much energy is released, and what the undersea terrain is like.

    The energy pulses, which are part of the earthquake sequence and take place almost immediately, differ from aftershocks that may occur hours, days, weeks or months after the original earthquake. In fact, the December Sumatra quake was followed by an 8.7 tremor in March and, though it occurred well to the south, "looks to have been directly triggered by the stress of the December event," Goldfinger said.

    "And there have been a lot of aftershocks since," he added.

    Goldfinger said it appears the Indian Ocean fault is rupturing in a southerly direction and that Padang, the capital of West Sumatra, may be next in line for a major earthquake.

    But whether that quake takes place in weeks or years remains to be seen. Though Padang's last major quake was about 200 years ago, the increased stress on the fault makes it likely that the lag between events will be much shorter.

    "When you load the stress on a fault, it shortens the time between quakes," Goldfinger pointed out. "It's like putting a sheet of glass between two sawhorses - and then sticking a cinder block in the middle of the glass. It may not break right away, but the stress builds rapidly."

    Comparatively little is known about the long-term tectonic history of the Indian Ocean - at least, compared to the Cascadia Subduction Zone, scientists say. Goldfinger has been able to identify 23 major earthquakes off the Pacific Northwest coast during the past 10,000 years through analysis of sediment deposits. At least 16, and possibly 17, of those quakes have ruptured along the entire length of the Cascadia Subduction Zone, requiring an event of magnitude 8.5 or better.

    When a major offshore earthquake of that magnitude occurs, "you get ground acceleration of a couple of G's," Goldfinger pointed out. "Mud and sand begin streaming down the continental margins, and out into the undersea canyons. Walls fail. And the sediments run out into the abyssal plain. The impact is much, much greater than you can get from any storm - or even a small magnitude quake."

    Those coarse sediments - called turbidites - stand out from the finer particulates that accumulate on a surprisingly regular basis in between major tectonic events. By studying core samples from submarine channels in various locations along the subduction zone, Goldfinger and his colleagues have been able to create a 10,000-year timeline of huge earthquakes that provide sobering evidence that the Northwest is due for a major event. Going back farther than 10,000 years is proving to be difficult.

    "The sea level used to be lower and rivers emptied directly into offshore canyons," he said. "You couldn't differentiate between storms and earthquakes. But once sea levels rose, the river sediments were trapped on the shelf and upper slope, leaving a near-perfect earthquake record farther out."

    Goldfinger said that evidence suggests turbidites might record earthquake pulses, but more testing is needed in Sumatra, where "we have good recordings of the earthquake."

    What the Indian Ocean lacks is the same long-term sediment analysis that has been done in the Cascadia zone, says Goldfinger, who adds that conditions there are ideal for such research. He and a team of scientists from Indonesia and India are planning a series of cruises over the next several years to take core samples from the Indian Ocean in an attempt to map the tectonic history of the region.

    "If anything, the Indian Ocean is even better suited than Cascadia for this kind of core analysis because there is a huge basin between the rivers and the deep ocean that keeps the terrestrial sediments close to land," Goldfinger said. "We should clearly be able to see the December and March turbidites stacked on top of the finer sediments."

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    Chris Goldfinger, 541-737-5214

    One Year Later: Huge Tsunami Spurred Progress, Revealed Needs

    CORVALLIS, Ore. - The catastrophic tsunami that struck Indonesia and East Asia almost a year ago has done much to heighten the interest, research programs and preparations in the United States for events of this type, but experts say there are areas that need more attention and challenges yet to be met.

    Dec. 26 will mark the first anniversary of the tsunami that claimed the lives of about 275,000 people and struck with waves up to 100 feet high, one of the deadliest disasters in modern history.

    Since that time, Congress has worked on legislation that would enable the National Oceanic and Atmospheric Administration to spend $35 million per year for a major expansion and improvement of warning systems in the United States, and support other smaller research or disaster planning initiatives around the nation in a U.S. Tsunami Warning Network.

    But scientists at Oregon State University, which operates one of the world's leading tsunami research facilities, say more studies are necessary on expected wave behavior at specific coastal locations, the probable impact on structures and measures that could be taken to reduce casualties and damage.

    "The significant support to NOAA is a good sign that the risks of tsunamis are finally being taken more seriously," said Harry Yeh, the Edwards Professor of Ocean Engineering at OSU and a leading international expert on tsunamis. "The majority of that will be focused on early detection systems in the Pacific Ocean and Caribbean Sea to improve warnings about tsunamis originating from distant locations."

    However, according to Yeh and Dan Cox, an associate professor and director of the Hinsdale Wave Research Laboratory at OSU (http://wave.oregonstate.edu/), there are still pressing educational, research and planning needs. They have special urgency in the Pacific Northwest - the North American location most vulnerable to a tsunami that would strike with little forewarning -- from the nearby Cascadia Subduction Zone.

    "Much of our current approach to tsunami preparation is about warning systems and getting people out of the way," Cox said. "In some cases, that's appropriate. But there are also serious questions about how practical it will be to evacuate large numbers of people in towns that are accessible by a two-lane road. We will have only a very short time - 20 to 30 minutes, not hours - in the case of the Cascadia Subduction Zone tsunami."

    "So we should consider other approaches to protect public safety like designing hotels or parking garages that would be strong enough and high enough to provide a local haven for people who would not be able to reach higher ground," he said. "The emphasis on warning systems also does little to help the personnel responding to the disaster. For example, will debris make some roads inaccessible?"

    Studies addressing those topics are conducted at OSU in its Tsunami Wave Basin, a sophisticated, $4.8-million facility in which scientists can simulate, in miniature, the forces and behavior of waves as they approach a coastline with various features and types of undersea topography. Researchers all over the world use the facility, the largest of its type in the world, for advanced tsunami research.

    And last year, both Yeh and OSU civil engineering professor Solomon Yim did field research in East Asia on the behavior and impacts of the tsunami there.

    "One big change we need is better interdisciplinary research in this field," Yeh said. "We have to get seismologists and marine geologists talking to civil engineers, so we can get better tsunami-source information to propagation models for prediction of coastal effects. We need to have social scientists working with disaster planners so that evacuation plans are realistic and actually work in the short time frame we may have available. We soon plan to begin research on the social dynamics of this problem."

    In Oregon, Yeh said, there's also an inadequate analysis of the specific marine terrain at various coastal towns and the implications that would have for a tsunami wave run-up. Much more work also needs to be done on the impacts of large, heavy debris sloshing back and forth in repeated tsunami waves - a problem vividly illustrated in the enormous structural damage caused by the East Asian tsunami.

    With more research, it might be possible to construct at least some future buildings with methods that would better resist damage or destruction by tsunami waves, the OSU researchers say. The Oregon Sea Grant Program has provided a two-year, $170,000 grant to support fundamental research in this area.

    "The number of fatalities from earthquakes in the U.S. is actually very low, because a long time ago we realized the dangers they pose and changed our building codes to start planning for them," Cox said. "But we don't have comparable building codes for tsunami-resistant structures."

    The major tsunami of last year has also caused a surge of student interest in study and research on this field, the OSU experts said, that could be tapped to better prepare the scientists of the future who will continue to deal with the threats posed by these catastrophic events.

    Some experts say there is a 10-14 percent chance that there could be a massive earthquake and tsunami on the Cascadia Subduction Zone within 50 years. The last such event is believed to have happened in 1700, and 23 major earthquakes have been recorded on this fault zone, which runs from northern California to Vancouver Island, in the past 10,000 years.

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    Dan Cox, 541-737-3631

    "Borehole" data suggests Earth's warming at faster pace

    CORVALLIS, Ore. - A temperature analysis of more than 600 boreholes from throughout the Northern Hemisphere suggests that the Earth's climate may be warming at a higher rate than tree-ring analysis and other methods had led scientists to believe.

    "If we're right, these boreholes are showing that the Earth is more sensitive to whatever is forcing the climatic change," said Robert N. Harris, an associate professor in the College of Oceanic and Atmospheric Sciences at Oregon State University and a principal investigator in the study.

    Results of the research by Harris and colleague David S. Chapman of the University of Utah were just published in the Journal of Geophysical Research. The researchers also will present their data in December at the annual meeting of the American Geophysical Union.

    Borehole temperatures have been measured since the 1920s, but only recently has this temperature analysis been applied to global warming studies. Unlike most "proxy" methods to reconstruct climate models, which depend entirely on statistical analysis, borehole temperature research is based on the physics of heat diffusion.

    Harris offers an analogy to describe how it works.

    "On a smaller scale, it's similar to underground pipes freezing in the spring instead of during the coldest part of winter," he said. "It takes time for the cold winter temperatures to propagate through the ground. Similarly, if you put one end of a steel poker into a fire, and hold the other end, the heat propagates toward your hand.

    "If at some later time you take a series of temperature measurements along the length of the rod, you would be able to estimate the temperature of the fire and how long the poker had been in the fire. The distance the poker had warmed is related to time, and the amount of warming is related to the temperature of the fire."

    In the ground, rocks are such poor conductors of heat that the effect of a changing surface temperature 500 years ago is felt at a depth of about 200 meters, Harris says. The scientists make careful temperature measurements in boreholes that are as deep as 500 meters. These temperatures reflect the adjacent rock and tell the researchers how temperatures have changed over long periods of time.

    What the research cannot tell scientists is what the temperature may have been for a particular year, Harris said.

    "Heat diffusion causes the signal to get smeared out, so the deeper you look, the smaller the signal," he pointed out. "Eventually, the signal is lost in background noise. This process also means that you only get multi-year averages."

    Harris and Chapman examined temperature data from boreholes throughout the Northern Hemisphere, which helps eliminate regional anomalies in their findings. They estimate that the Earth has warmed 1.1 degrees C. over the past 500 years - more than double the 0.4- to 0.5-degree estimates suggested by most tree-ring analysis.

    In their article, they say the difference may be that tree-ring analysis primarily reflects temperatures when trees are actively growing during the warm season, but doesn't reflect changes in winter temperatures. Much of the annual warming recorded by instruments over the past 100 years has occurred during the winter season, they add.

    The boreholes used in the research were generated from a variety of sources, including mineral exploration, dry water wells and those done specifically for the temperature research. The best environment for drilling, Harris says, is where the rock is solid and impermeable, limiting advection.

    A typical borehole may be six inches in diameter and 200 meters deep. Much deeper and the temperature differences become too minute to pick up, Harris said. However, that depth allows them to take measurements that go back about 500 years - or roughly the time Columbus was first approaching the New World.

    "We know by comparative data that borehole analysis, as remarkable as it may seem, really works," Harris said. "For the periods of overlap when we can compare with recorded temperature data, the correlation is excellent. Beyond that, it is simply a matter of applying the physics of heat diffusion. "And those measurements tell us the Earth is warming faster than we previously thought."

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    Rob Harris, 541-737-4370

    COAS, Sea Grant project to link adult education, marine sciences

    CORVALLIS, Ore. - Thirteen instructors from Oregon community colleges are spending three days with scientists from Oregon State University, the National Oceanic and Atmospheric Administration, and Oregon Sea Grant at OSU's Hatfield Marine Science Center as part of an initiative to incorporate ocean sciences into adult education and workforce development.

    This instructor institute, which runs from Nov. 3-5, is the first of three in the year-long Ocean Sciences and Math Collaborative Project.

    During this institute, the 13 educators will learn more about the ocean and its role in the Earth's climate - and how that complex system affects Oregon's weather, economy, public health and jobs. They will then use the information to better inform their students about ocean sciences issues.

    "Ultimately, these instructors will be the ones delivering the message to adult learners," said Robert Collier, an OSU professor in the College of Oceanic and Atmospheric Sciences. He co-directs the program with colleague Marta Torres, Susan Cowles and Jon Luke.

    Much of the information comes from scientists involved directly with significant research, Collier said. The educators also will receive classroom materials and tips on how to integrate the research findings into relevant curriculum that integrates math, writing, language acquisition and reading instruction, as well as ocean sciences.

    The instructors represent diverse programs, including workforce training, adult basic education, workplace education (cannery workers), adult secondary education (GED preparation), English to speakers of other languages, and family literacy.

    Instructors attending the institute include:

  • Boardman: Shannon Maude, Blue Mountain Community College;
  • Glide: John Druzik, Umpqua Community College/Wolf Creek Job Corps;
  • Gresham: Donna Ball, Mt. Hood Community College;
  • North Bend: Bonnie Maxwell, Southwestern Oregon Community College;
  • Ontario: Linda McDowell and Yolanda Morales, Treasure Valley Community College;
  • Pendleton: Marjie Prowant, Blue Mountain Community College;
  • Portland: David Bunk and Laura Moulton, Mt. Hood Community College;
  • Rogue River : Lori Savage, Rogue Community College;
  • Roseburg: Jerry Fullerton, Umpqua Community College;
  • The Dalles: Susan Lewis, Columbia Gorge Community College;
  • West Linn: Linda Daugherty, Portland Community College.
  • Story By: 

    Bob Collier, 541-737-4367

    Scientists concerned about changes in Arctic

    CORVALLIS, Ore. - For the past 10 years, Kelly Falkner has studied water circulation patterns in the Arctic Ocean, which acts like a big valve and influences ocean circulation and climate throughout the entire globe.

    And during the time she has been observing the Arctic, Falkner has witnessed significant changes, the Oregon State University oceanographer said today at a meeting of the United States Arctic Research Commission on the OSU campus.

    "During our 2003 cruise to Nares Strait, we were able to get our ship further into the Petermann Gletscher Fiord (a glacier off northern Greenland) than any ship has ever gone before," Falkner said. "This is because the floating tongues of the continental ice sheet are retreating all around Greenland more than they ever have in recorded human history."

    The U.S. Arctic Commission's annual fall meeting is in Corvallis, Ore., this year, where the seven-member group heard reports from more than a dozen Oregon State University scientists involved in Arctic research. The commission, which advises the president and Congress, includes four members from academic or research institutions, two from private industry undertaking commercial activities in the Arctic, and one from the indigenous residents of the Arctic.

    Falkner, who is involved in two major Arctic initiatives funded by the National Science Foundation, outlined her research through which she can trace the origins of Arctic waters hundreds of miles from their sources by their naturally occurring chemical signatures.

    The ratio of stable oxygen isotopes in water, for example, can tell scientists if the waters in a given part of the Arctic came from river water or melted sea ice. The nutrient levels reveal if sea water originated from the Atlantic or the Pacific Ocean. And whether rivers drain from Eurasia or North America can be traced by their levels of barium and their alkalinity.

    Falkner and colleagues in OSU's College of Oceanic and Atmospheric Sciences and elsewhere are mapping the complex circulation patterns of the Arctic Ocean and how they are changing. It is incredibly important work, experts say, because small changes in the Arctic can have large implications.

    "Ten percent of the world's river water drains into the Arctic, which represents just 1 percent of the world's ocean volumes," Falkner said. "The water flowing out of the Arctic can have impacts on ocean circulation, and thus climate, throughout the world."

    Much of the news media coverage on global warming has focused on the potential for rising sea levels, Falkner said. For sea levels to rise, land-based glaciers or snow would have to melt. Less attention has been paid to the melting of sea ice, which may not raise sea levels but could dramatically affect ocean and atmosphere circulation - and the Earth's heat balance, she pointed out.

    Falkner said that since 1978, when satellite measurements of Arctic ice first became available, the overall ice cap has shrunk more than 8 percent each decade. Some scientists feel enough ice has gone to create an "albedo threshold," which means it may not stay cold enough for a long enough period to re-establish the lost ice.

    "Sea ice with snow on it reflects up to 90 percent of the energy from the sun," Falkner said. "Water, on the other hand, absorbs 70 percent or more of the incoming sun energy. So when there is a lot of ice, the heat is reflected. Now that the ice is receding rapidly, the water is absorbing more heat, and it becomes that much harder to re-establish that ice."

    Falkner began her work in the Arctic during the early 1990s, when she received a Young Investigator Award from the Office of Naval Research to begin sampling Arctic rivers to determine their chemical signatures. One of the goals of that research was to monitor potential spreading of Russian nuclear waste in the post-Soviet Union era.

    Now her focus is on understanding Arctic circulation and what drives its variability. Falkner and her colleagues are halfway through a five-year NSF grant to study fresh water fluxes into the North Atlantic east of Greenland in the Nares Strait. That research was stalled this spring when most of the team's equipment was blown away by extraordinarily strong winds.

    "There were 80-mile-per-hour-plus winds, equivalent to a category-2 hurricane, that literally blew everything away," Falkner said. "Fortunately, folks managed to hang to one shelter and no one was killed or injured in the fierce cold. We were unable to check the instruments we had moored below the ice, but luckily we put extended batteries in them last year as a contingency.

    "People are beginning to think that the Arctic is an accessible place, but it's not," she added. "It is very complex and you always have to have great respect for it."

    Falkner and her colleagues have another cruise lined up for August of 2006 to check the instrumentation that will tell them more about the changing currents of the Arctic Ocean.

    Story By: 

    Kelly Falkner, 541-737-3625

    Rapid breakup of glaciers raising sea level concerns

    CORVALLIS, Ore. - The rapid structural breakdown of some important parts of the ice sheets on Greenland and Antarctica is possible and has happened in the distant past, and some "startling changes" on the margin of these ice masses has been observed in recent years, raising disturbing concerns about sea level rise.

    In a new report to be released Friday in the journal Science, researchers from Oregon State University and four other institutions in the U.S. and Europe outline dynamic mechanisms of glacial change that appear to be under way. These changes could significantly speed up the melting of major ice sheets, and have not been considered in current projections for sea level rise.

    A possibility, scientists say, is that the melting and collapse of floating ice shelves near the coasts of Greenland and Antarctica will continue and in the process destabilize the ice sheets behind them. This could cause a much more rapid flow of ice to the sea and lead to melting events that transcend those now anticipated due to global warming. Based on this, the researchers say that current projections of sea level rise should be considered an expected minimum; the levels could be much higher and happen more quickly.

    "Most of the sea level rise we're now expecting in the next 200 years is due to thermal expansion of water, not the overall loss of ice from Greenland and Antarctica," said Peter Clark, a professor of geosciences at OSU. "But recent events we've studied with improved observational systems and computer modeling suggest there may be much more going on.

    "We may be more vulnerable to sea level rise than we thought and it may be more rapid than we have anticipated. This is an issue we should take very seriously." Although they are learning a great deal more about the mechanisms that may lead to more rapid glacial collapse, the scientists cannot yet predict with certainty whether or how fast it might happen, or what the resulting sea level rise may be.

    In one event about 14,600 years ago, Earth's sea level rose about 70 feet in less than 500 years - 20 times faster than the current rate of sea level rise. However, climatic conditions then may have been considerably different than today, and that event may not provide an exact analog to what we might expect from current glacial melting events, Clark said. Nevertheless, that event illustrates the potential for existing ice sheets to cause sea level to rise rapidly, he said.

    Current projections in climate models suggest that global warming will cause some melting of glacial ice in Greenland in the next century or two, but that may be largely offset by increased precipitation and glacial buildup in Antarctica. During that period, thermal warming of the Earth's oceans is expected to increase sea level by about one-half meter, Clark said. The breakdown of glaciers currently being studied could double the sea level rise to a full meter, he said.

    More problems are anticipated later. The Greenland ice sheet may disappear within about 1,000 years, raising Earth's sea level by about 20 feet, and the glacial breakdown mechanisms being studied could speed that up considerably.

    What has caught the attention of scientists in recent years is the rapid collapse of some glaciers near the coasts of Greenland and Antarctica.

    Jakobshavn glacier in Greenland nearly doubled its flow speed in the past decade. Along the Antarctic Peninsula, warming over the past few decades has caused retreat or near-total loss of several ice shelves, some of which had existed for thousands of years - and surface melting cannot explain most of the losses. In 2002 the Larsen B Ice Shelf in Antarctica collapsed, and major tributary glaciers entering the former ice shelf began to move 2-8 times faster than they had previously. Also in Antarctica, large glaciers feeding the Amundsen Coast thinned and accelerated by up to 26 percent over the last three decades, with repercussions more than 120 miles inland.

    It's become clear, Clark said, that the West Antarctic Ice Sheet, much of which sits on land that's actually below sea level, is one of the most vulnerable in the world to these types of rapid breakdowns. If it were to melt, that would add another 20 feet to global sea levels.

    In future modeling of potential sea level rise, the researchers said in their report, it's essential that the mechanisms for breakup of major ice sheets in Greenland and Antarctica be more carefully considered in the projections. If these mechanisms continue and prove to be significant, sea level projections will have to be revised upward, the scientists said.

    Other collaborators on this study were from Pennsylvania State University, the University of Washington, and institutes or universities in Germany and Belgium.

    "The events that have happened so far are pretty small, compared to what we're concerned about," Clark said. "The real problem would occur if these smaller glacial breakups trigger larger ones, and rising sea levels by themselves might cause a feedback mechanism which would further speed up the process."

    Story By: 

    Peter Clark, 541-737-1247

    U.S. Artctic Research Commission to meet at OSU

    CORVALLIS, Ore. - The United States Arctic Research Commission will hold its annual fall meeting Oct. 25-27 at Oregon State University, where the seven commissioners will hear scientific presentations by more than a dozen OSU researchers.

    The commission is an advisory body that recommends Arctic research policy to the president and Congress. It was established in 1984 to develop a federal program for basic and applied research related to the Arctic.

    "The visit by the commission brings a lot of attention and prestige to the university," said Mark Abbott, dean of the College of Oceanic and Atmospheric Sciences (COAS). "OSU has a lot of important research focusing on the Arctic by faculty from a number of different colleges and academic backgrounds. Because of global warming concerns and discussions about drilling, the Arctic has been the focus of a lot of interest of late, so the timing for the visit couldn't be better."

    The commissioners will spend Tuesday and Wednesday on OSU's main campus in Corvallis, where they will hear a number of presentations from faculty. The meeting will run from 8:30 a.m. to 4:40 p.m. on Tuesday and 9 a.m. to noon on Wednesday at the CH2M-Hill Alumni Center. On Thursday, the commission will move to Newport for sessions at OSU's Hatfield Marine Science Center running from 8:30 a.m. to noon. The sessions are free and open to the public, though space may be limited.

    A public discussion on Arctic research will begin at 11 a.m. on Thursday, Oct. 27, at OSU's Hatfield Marine Science Center in Newport.

    The agenda for the three-day meeting is available online at http://www.coas.oregonstate.edu/.

    Topics covered in the OSU presentations include:

  • "Tracer Hydrography of the Arctic Ocean," by Kelly Falkner, COAS (9:40 a.m., Tuesday);
  • "Submarine-based Observations of the Upper Layers of the Arctic Ocean," Tim Boyd, COAS (10:25 a.m., Tuesday);
  • "The Geomagnetic Field of the Arctic: Understanding Possible Futures from Reconstructing the Past," Joe Stoner, COAS (10:50 a.m., Tuesday);
  • "Contaminants in the Arctic: National Parks as Sentinel Ecosystems," by Kim Hageman, Department of Environmental and Molecular Toxicology (11:15 a.m., Tuesday);
  • "Rain, Fog, Hugs and Tears: Results of the 2005 NSF-funded Field Season on King Island, Alaska," Deanna Kingston, Department of Anthropology (11:40 a.m., Tuesday);
  • "Permafrost Engineering Issues," Ted Vinson, College of Engineering (3:25 p.m., Tuesday);
  • "Arctic Ice Cores and the History of Abrupt Climate Change," Ed Brook, Department of Geosciences (3:50 p.m., Tuesday);
  • "Recent Large Albedo Decreases on a Greenland Outlet Glacier," Anne Nolin, Department of Geosciences (4:15 p.m., Tuesday);
  • "Geochemistry of the Gakkel Ridge: Ultraslow Seafloor Spreading at the Top of the World," David Graham, COAS (9 a.m., Wednesday);
  • "Microbial Ecology in the Arctic Ocean," Ev and Barry Sherr, COAS (9:30 a.m., Wednesday);
  • "Modeling Arctic Ocean Ecosystems," Yvette Spitz, COAS (10:55 a.m., Wednesday);
  • "Fisheries Behavioral Ecology in Alaskan Waters," Cliff Ryer, NOAA Alaska Fisheries Science Center (8:45 a.m., Thursday, Newport);
  • "Free Choice Learning Initiative," Shawn Rowe, Extension Sea Grant (9:10 a.m., Thursday, Newport);
  • "Exploring Submarine Activity off the Antarctic Peninsula Using Passive Underwater Acoustics," Robert Dziak, OSU Hatfield Marine Science Center (10 a.m., Thursday, Newport);
  • "Satellite Tracking Studies of Albatrosses in the Bering Sea and Aleutian Islands," Rob Suryan, OSU Hatfield Marine Science Center (10:25 a.m., Thursday, Newport).

    The U.S. Arctic Research Commission's seven members include four from academic or research institutions, two from private industry undertaking commercial activities in the Arctic, and one from the indigenous residents of the Arctic. The director of the National Science Foundation serves as an ex-officio member.

  • Story By: 

    Mark Abbott, 541-737-5195