OREGON STATE UNIVERSITY

marine science and the coast

Researchers measure giant “internal waves” that help regulate climate

CORVALLIS, Ore. – Once a day, a wave as tall as the Empire State Building and as much as a hundred miles wide forms in the waters between Taiwan and the Philippines and rolls across the South China Sea – but on the surface, it is hardly noticed.

These daily monstrosities are called “internal waves” because they are beneath the ocean surface and though scientists have known about them for years, they weren’t really sure how significant they were because they had never been fully tracked from cradle to grave.

But a new study, published this week in Nature Research Letter, documents what happens to internal waves at the end of their journey and outlines their critical role in global climate. The international research project was funded by the Office of Naval Research and the Taiwan National Science Council.

“Ultimately, they are what mixes heat throughout the ocean,” said Jonathan Nash, an Oregon State University oceanographer and co-author on the study. “Without them, the ocean would be a much different place. It would be significantly more stratified – the surface waters would be much warmer and the deep abyss colder.

“It’s like stirring cream into your coffee,” he added. “Internal waves are the ocean’s spoon.”

Internal waves help move a tremendous amount of energy from Luzon Strait across the South China Sea, but until this project, scientists didn’t know what became of that energy. As it turns out, it’s a rather complicated picture. A large fraction of energy dissipates when the wave gets steep and breaks on the deep slopes off China and Vietnam, much like breakers on the beach.

But part of the energy remains, with waves reflecting from the coast and rebounding back into the ocean in different directions.

The internal waves are caused by strong tides flowing over the topography, said Nash, who is in OSU’s College of Earth, Ocean, and Atmospheric Sciences. The waves originating in Luzon Strait are the largest in the world, based on the region’s tidal flow and topography. A key factor is the depth at which the warm- and cold-water layers of the ocean meet – at about 1,000 meters.

The waves can get as high as 500 meters tall and 100-200 kilometers wide before steepening.

“You can actually see them from satellite images,” Nash said. “They will form little waves at the ocean surface, and you see the surface convergences piling up flotsam and jetsam as the internal wave sucks the water down. They move about 2-3 meters a second.”

The waves also have important global implications. In climate models, predictions of the sea level 50 years from now vary by more than a foot depending on whether the effects of these waves are included.

“These are not small effects,” Nash said.

This new study, which was part of a huge international collaboration involving OSU researchers Nash and James Moum – as well as 40 others from around the world – is the first to document the complete life cycle of these huge undersea waves.

Media Contact: 
Source: 

Jonathan Nash, 541-737-4573, nash@coas.oregonstate.edu

Multimedia Downloads
Multimedia: 

internalwaves

Large "internal waves" are generally not seen at the surface, but their signature is - visible slicks and changes in surface roughness and color.

Solomon Islands dolphin hunts cast spotlight on small cetacean survival

NEWPORT, Ore. – A new study on the impact of ‘drive-hunting’ dolphins in the Solomon Islands is casting a spotlight on the increasing vulnerability of small cetaceans around the world.

From 1976 to 2013, more than 15,000 dolphins were killed by villagers in Fanalei alone, where a single dolphin tooth can fetch the equivalent of 70 cents ($0.70 U.S.) – an increase in value of five times just in the last decade.

Results of the Solomon Islands study are being reported this week online in the new journal, Royal Society Open Science.

“In the Solomon Islands, the hunting is as much about culture as economic value,” said Scott Baker, associate director of the Marine Mammal Institute at Oregon State University and co-author on the study. “In other parts of the world, however, the targeting of dolphins and other small cetaceans appears to be increasing as coastal fishing stocks decline.

“The hunting of large whales is managed by the International Whaling Commission,” added Baker, who works out of OSU’s Hatfield Marine Science Center in Newport, Ore. “But there is no international or inter-governmental organization to set quotas or provide management advice for hunting small cetaceans. Unregulated and often undocumented exploitation pose a real threat to the survival of local populations in some regions of the world.”

The drive-hunting of dolphins has a long history in the Solomon Islands, particularly at the island of Malaita, according to Marc Oremus, a biologist with the South Pacific Whale Research Consortium and lead author on the study. In 2010, the most active village, Fanalei, suspended hunting in exchange for financial compensation from an international non-governmental organization. The villagers resumed hunting in 2013.

“After the agreement broke down in 2013, a local newspaper reported that villagers had killed hundreds of dolphins in just a few months,” Oremus said. “So we went to take a look.”

Oremus and co-author John Leqata, a research officer with the Ministry of Fisheries and Marine Resources, visited Fanalei in March of 2013 to document the impact on the population, and examine detailed records of the kills. During the first three months of that year, villagers killed more than 1,500 spotted dolphins, 159 spinner dolphins, and 15 bottlenose dolphins.

This is one of the largest documented hunts of dolphins in the world, rivaling even the more-industrialized hunting of dolphins in Japan, noted Baker, whose genetic identification research was featured in the Academy Award-winning documentary on dolphin exploitation, “The Cove.”

“It is also troubling that teeth are increasing in cash value, apparently creating a commercial incentive for hunting dolphins,” Baker said.

In drive-hunting, the hunters operate in close coordination from 20 to 30 traditional canoes. When dolphins are found, the hunters used rounded stones to create a clapping sound underwater. The hunters maneuver the canoes into a U-shape around the dolphins, using sound as an acoustic barrier to drive them toward shore where they are killed.

“The main objective of the hunt is to obtain dolphin teeth that are used in wedding ceremonies,” Oremus said. “The teeth and meat are also sold for cash.”

Oremus said the Solomon Island hunters understand the risk of exploiting the population.

“The government of the Solomon Islands has contributed substantially to research in recent years, but is not well-equipped to undertake the scale of research needed to estimate abundance and trends of the local dolphin population,” Oremus said. “This problem exists in many island nations with large ‘Exclusive Economic Zones.’”

The research was supported by the International Fund for Animal Welfare, the Pew Environmental Group and the International Whaling Commission.

Media Contact: 
Source: 

Scott Baker, 541-272-0560, scott.baker@oregonstate.edu

Multimedia Downloads
Multimedia: 




dolphinteeth

Dolphin teeth are sold for necklaces

Emeritus OSU geologist outlines earthquake “time bombs” in a forthcoming book

CORVALLIS, Ore. – An emeritus Oregon State University geologist, who was one of the first scientists to point to the possibility of a major earthquake in the Pacific Northwest, outlines some of the world’s seismic “time bombs” in a forthcoming book.

One of those time bombs listed, in a segment he wrote last year, was Nepal where on April 25, an earthquake estimated at magnitude 7.8 struck the region, killing more than 7,500 people and injuring another 14,500.

Robert Yeats’ prescience is eerily familiar.

Five years ago, Yeats was interviewed by Scientific American on earthquake hazards and outlined the dual threats to Port au Prince, Haiti, of poverty and proximity to a major fault line. One week later, that time bomb went off and more than 100,000 people died in a catastrophic earthquake.

When the Scientific American reporter called Yeats after that seismic disaster to ask if he had predicted the quake, he said no.

“I could say where the time bombs are located – large, rapidly growing cities next to a tectonic plate boundary with a past history of earthquakes, but I had no way of knowing that the bomb would go off a week after my interview,” he said.

Fast forward to 2015 – Yeats has completed a new book, “Earthquake Time Bombs,” which will be published later this year by Cambridge University Press. In that book, he identifies other time bombs around the world; one is a region he has visited frequently in the past 30 years – the Himalayas, including Kathmandu, Nepal, a city of more than a million people.

Yeats points to several areas around the worlds where large cities lie on or adjacent to a major plate boundary creating a ticking time bomb: Tehran, the capital of Iran; Kabul in Afghanistan; Jerusalem in the Middle East; Caracas in Venezuela; Guantanamo, Cuba; Los Angeles, California; and the Cascadia Subduction Zone off the northwestern United States and near British Columbia.

“These places should take lessons from the regions that already have experienced major earthquakes, including Nepal,” said Yeats, who is with OSU’s College of Earth, Ocean, and Atmospheric Sciences.

Like Port au Prince, Kathmandu lies on a tectonic plate boundary – the thrust fault between the high Himalayas and the continent of India to the south. The plate began its northward movement 50 million years ago, Yeats said, and is progressing at the rate of about two-thirds of an inch a year. As the plate is forcing its way beneath Tibet, it is triggering periodic earthquakes along the way.

“It takes time to build up a sufficient amount of stress in these systems, but eventually they will rupture,” Yeats said. “The 2015 Nepal quake was, unquestionably, a disaster with losses of life in the thousands. But it could have been worse.”

“With the assistance of an American non-profit seismology group, the city of Kathmandu created a disaster management unit and a National Society for Earthquake Technology that established committees of citizens to raise awareness and upgrade buildings, especially public schools,” Yeats pointed out. “Other ‘time bombs’ would be wise to do the same.”

Making buildings more earthquake-resistant is imperative for cities near a fault, yet economics often preclude such measures. Yeats said some of the greatest losses in the Nepal quake took place in United Nations World Heritage sites of Bhaktapur and Patan, where ancient buildings had not been strengthened.

“We are not able to predict an earthquake, but we can identify potential trouble,” Yeats said. A seismic gap in the Himalayas was identified years ago by the late Indian seismologist K.N. Khattri in between western Himalaya of India and Kathmandu, where a magnitude 8.1 quake hit in 1934, he pointed out. The earthquake on April 25 struck within Khattri’s seismic gap, Yeats noted.

The 1934 earthquake killed an estimated 20 percent of the population of Kathmandu Valle, some 30,000 people. The population there was much smaller than it is today.

“The 1934 epicenter apparently was east of the city, whereas the epicenter of April 25’s earthquake was to the west, meaning that the two earthquakes may have ruptured different parts of the plate-boundary fault,” Yeats said.

Earlier earthquakes that damaged Kathmandu struck in 1833 and 1255. The location and magnitude of those two quakes are uncertain.

“Videos of this year’s earthquake focused on damaged and destroyed buildings and many of these were old historical buildings that had not been upgraded,” Yeats said. “Photos also showed new buildings that did not appear to be damaged. There’s a lesson there.”

Media Contact: 
Source: 

Robert “Bob” Yeats, yeatsr@science.oregonstate.edu

Researchers think Axial Seamount off Northwest coast is erupting – right on schedule

NEWPORT, Ore. – Axial Seamount, an active underwater volcano located about 300 miles off the coast of Oregon and Washington, appears to be erupting – after two scientists had forecast that such an event would take place there in 2015.

Geologists Bill Chadwick of Oregon State University and Scott Nooner of the University of North Carolina Wilmington made their forecast last September during a public lecture and followed it up with blog posts and a reiteration of their forecast just last week at a scientific workshop.

They based their forecast on some of their previous research – funded by the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA), which showed how the volcano inflates and deflates like a balloon in a repeatable pattern as it responds to magma being fed into the seamount.

Since last Friday, the region has experienced thousands of tiny earthquakes – a sign that magma is moving toward the surface – and the seafloor dropped by 2.4 meters, or nearly eight feet, also a sign of magma being withdrawn from a reservoir beneath the summit. Instrumentation recording the activity is part of the NSF-funded Ocean Observatories Initiative. William Wilcock of the University of Washington first observed the earthquakes.

“It isn’t clear yet whether the earthquakes and deflation at Axial are related to a full-blown eruption, or if it is only a large intrusion of magma that hasn’t quite reached the surface,” said Chadwick, who works out of OSU’s Hatfield Marine Science Center in Newport and also is affiliated with NOAA’s Pacific Marine Environmental Laboratory. “There are some hints that lava did erupt, but we may not know for sure until we can get out there with a ship.”

In any case, the researchers say, such an eruption is not a threat to coastal residents. The earthquakes at Axial Seamount are small and the seafloor movements gradual and thus cannot cause a tsunami. Nor is the possible eruption tied to a possible Cascadia Subduction Zone earthquake.

“I have to say, I was having doubts about the forecast even the night before the activity started,” Chadwick admitted. “We didn’t have any real certainty that it would take place – it was more of a way to test our hypothesis that the pattern we have seen was repeatable and predictable.”

Axial Seamount provides scientists with an ideal laboratory, not only because of its close proximity to the Northwest coast, but for its unique structure.

“Because Axial is on very thin ocean crust, its ‘plumbing system’ is simpler than at most volcanoes on land that are often complicated by other factors related to having a thicker crust,” said Chadwick, who is an adjunct professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “Thus Axial can give us insights into how volcano magma systems work – and how eruptions might be predicted.”

Axial Seamount last erupted in 2011 and that event was loosely forecast by Chadwick and Nooner, who had said in 2006 that the volcano would erupt before 2014. Since the 2011 eruption, additional research led to a refined forecast that the next eruption would be in 2015 based on the fact that the rate of inflation had increased by about 400 percent since the last eruption.

“We’ve learned that the supply rate of magma has a big influence on the time between eruptions,” Nooner said. “When the magma rate was lower, it took 13 years between eruptions. But now when the magma rate is high, it took only four years.”

Chadwick and Nooner are scheduled to go back to Axial in August to gather more data, but it may be possible for other researchers to visit the seamount on an expedition as early as May. They hope to confirm the eruption and, if so, measure the volume of lava involved.

Evidence that was key to the successful forecast came in the summer of 2014 via measurements taken by colleagues Dave Caress and Dave Clague of Monterey Bay Aquarium Research Institute and Mark Zumberge and Glenn Sasagawa of Scripps Oceanographic Institution. Those measurements showed the high rate of magma inflation was continuing.

Media Contact: 
Source: 

Bill Chadwick, 541-867-0179, bill.chadwick@oregonstate.edu

Multimedia Downloads
Multimedia: 

 

 

 

 

 

 

 

 

 

 










Boca vent

Axial Seamount vent taken in 2011


NE-Pac-2011-Axial-Location-hires

OSU’s Aaron Wolf receives prestigious Heinz Award

CORVALLIS, Ore. – Oregon State University’s Aaron Wolf, an internationally recognized expert on water conflict resolution, has been named a 2015 recipient of the Heinz Award in the category of public policy.

Established to honor the memory of U.S. Sen. John Heinz, the awards recognize significant contributions in arts and humanities, environment, human condition, public policy, and technology, the economy and employment. Wolf’s award, given by the Heinz Family Foundation, includes an unrestricted cash award of $250,000.

Wolf was cited for “applying 21st-century insights and ingenuity, as well as ancient wisdoms, to problems that few are paying attention to for the security of the planet.”

“In a world where water is rapidly becoming the most precious of resources and most geopolitical of issues, Aaron Wolf has found practical solutions to protect our water resources and find common ground on water-centered conflicts,” said Teresa Heinz, chairman of the Heinz Family Foundation.

“Water issues cross state and national boundaries, and his advocacy has driven treaties and agreements that recognize our competing demands on water resources and the vital importance of protecting those resources from a modern-day ‘tragedy of the commons.’”

A professor of geography in Oregon State’s College of Earth, Ocean, and Atmospheric Sciences, Wolf decided early in his career to find ways to ease the tension over water rights, developing a negotiation approach that emphasizes listening and finding shared values among competing users.

Wolf also was cited for working to prepare future generations of scholars and leaders in water conflict resolution. He and other leading academics founded a consortium of 10 universities on five continents that seeks to build a global water governance culture focused on peace, sustainability and human security.

He also helped develop a new partnership between Oregon State, the UNESCO-IHE Institute for Water Education in The Netherlands and the University for Peace in Costa Rica that will offer a joint master’s degree program on water cooperation and peace.

“One thing I’m struck by over and over is what people of goodwill and creativity can accomplish, even in situations where everybody feels like they’re going to lose something,” Wolf said. “As I’ve watched the discourse change from water wars to water cooperation and peace, I’ve learned firsthand that people will resolve seemingly intractable problems when they’re given the space and the opportunity.”

Other Heinz Award winners include:

  • Roz Chast of Ridgefield, Connecticut, best-selling illustrator and cartoonist, the arts and humanities category;
  • Frederica Perera of New York, and environmental health researcher at Columbia University, the environment category;
  • William McNulty and Jacob Wood, founders of Team Rubicon in Los Angeles – which engages returning veterans to help in global relief efforts – the human conditions category;
  • Sangeeta Bhatia, a bioengineer at the Massachusetts Institute of Technology, in the technology, economy and employment category for pioneering efforts to cultivate liver cells outside the human body.

Wolf and the other winners will be honored at a ceremony on May 13 in Pittsburgh.

Media Contact: 
Source: 

Aaron Wolf, 541-737-2722; wolfa@geo.oregonstate.edu

Multimedia Downloads
Multimedia: 

Natural Resources Leadership Academy 2012
OSU's Aaron Wolf

Longest mammal migration raises questions about distinct species

NEWPORT, Ore. – A team of scientists from the United States and Russia has documented the longest migration of a mammal ever recorded – a round-trip trek of nearly 14,000 miles by a whale identified as a critically endangered species that raises questions about its status.

The researchers used satellite-monitored tags to track three western North Pacific gray whales from their primary feeding ground off Russia’s Sakhalin Island across the Pacific Ocean and down the West Coast of the United States to Baja, Mexico. One of the tagged whales, dubbed Varvara (which is Russian for Barbara), visited the three major breeding areas for eastern gray whales, which are found off North America and are not endangered.

Results of their study are being published this week by the Royal Society in the journal Biology Letters.

“The fact that endangered western gray whales have such a long range and interact with eastern gray whales was a surprise and leaves a lot of questions up in the air,” said Bruce Mate, director of the Marine Mammal Institute at Oregon State University and lead author on the study. “Past studies have indicated genetic differentiation between the species, but this suggests we may need to take a closer look.”

Western gray whales were thought to have gone extinct by the 1970s before a small aggregation was discovered in Russia off Sakhalin Island – with a present estimated population of 150 individuals that has been monitored by scientists from Russia and the U.S. since the 1990s.

Like their western cousins, eastern gray whales were decimated by whaling and listed as endangered, but conservation efforts led to their recovery. They were delisted in 1996 and today have a population estimated at more than 18,000 animals.

Not all scientists believe that western gray whales are a separate, distinct species. Valentin Ilyashenko of the A.N Severtsov Institute for Ecology and Evolution, who is the Russian representative to the International Whaling Commission, has proposed since 2009 that recent western and eastern gray whale populations are not isolated and that the gray whales found in Russian waters are a part of an eastern population that is restoring its former historical range. He is a co-author on the study.

“The ability of the whales to navigate across open water over tremendously long distances is impressive and suggests that some western gray whales might actually be eastern grays,” Mate said. “But that doesn’t mean that there may not be some true western gray whales remaining.

“If so, then the number of true western gray whales is even smaller than we previously thought.”

Since the discovery that western and eastern gray whales interact, other researchers have compared photo catalogues of both groups and identified dozens of western gray whales from Russia matching whale photographs taken in British Columbia and San Ignacio Lagoon in Baja California, Mexico.

Protecting the endangered western gray whales has been difficult – five whales have died in Japanese fishing nets within the last decade. Their feeding areas off Japan and Russia include fishing areas, shipping lanes, and oil and gas production – as well as future sites oil sites. Their largely unknown migration routes may include additional hazards.

The study was coordinated by the International Whaling Commission, with funding provided by Exxon Neftegas Limited, the Sakhalin Energy Investment Company, the U.S. Office of Naval Research, and OSU’s Marine Mammal Institute.

Media Contact: 
Source: 

 Bruce Mate, 541-867-0202, bruce.mate@oregonstate.edu; Ladd Irvine, 541-867-0394, ladd.irvine@oregonstate.edu

Multimedia Downloads
Multimedia: 

 

 

 

 

 

 

 

 

 

 

 

 

 

spouts

 

Western Gray Whale - Sakhalin Island, Russia

 

whale1

 

Photos by Craig Hayslip, OSU Marine Mammal Institute

OSU to host Marine Science Day at Hatfield Marine Science Center

NEWPORT, Ore. – The Hatfield Marine Science Center will hold its annual Marine Science Day on Saturday, April 11, commemorating the 50th anniversary of this unique Oregon State University facility.

Dedicated in 1965, the center has become an integral part of coastal development, education, research, tourism and economics. Marine Science Day runs from 10 a.m. to 4 p.m. at the center, located southeast of the Hwy. 101 bridge over Yaquina Bay in Newport.

“Marine Science Day is how we give back to the coastal, statewide and international communities we serve, but it is also a way to honor the past and celebrate the future in this, our 50th year,” said Bob Cowen, director of the center. “We will have many of our former faculty, staff and students at HMSC for a reunion that weekend, which will be very meaningful.

“We will get to see the shoulders we are standing on and harness 50 years of momentum as we look to the future,” he added.

Marine Science Day, which is free and open to the public, will also feature special exhibits about OSU’s new Marine Studies Initiative, which calls for OSU to host 500 students-in-residence at the Oregon coast by the year 2025 for a new, highly experiential undergraduate and graduate program in marine studies.

Oregon State is raising funds for a new teaching and research facility on the Hatfield Marine Science Center campus.

Among the events during Marine Science Day are:

  • Interactive displays by researchers from Oregon State and its federal and state government agency partners;
  • Demonstrations from the OSU acoustics research group, where you will be able to “see” your voice on a spectrogram;
  • An opportunity to become a citizen scientist and learn how to monitor sea star wasting disease with researchers from PISCO – the Partnership for Interdisciplinary Studies of Coastal Oceans;
  • Tidal touch pools with the Oregon Department of Fish and Wildlife’s shellfish program;
  • Tours of the OSU animal husbandry program and the Oregon Coast Community College aquarium science program.

Several research groups at HMSC will offer unprecedented access to their studies, facilities and instruments during the event.

In addition to a see-your-voice exhibit, the acoustics group will have a display with a large hydrophone and sub-woofers so participants can hears actual sounds from the ocean. The Earth-Ocean interactions program will show video of undersea volcanoes and hydrothermal vents. The Plankton Portal program will show beautiful, fascinating images of plankton as part of a major international initiative to learn more about these small marine creatures.

OSU’s Marine Mammal Institute will help participants identify whales through binoculars, and the Molluscan Broodstock program will show its oyster and seaweed research projects.

Marine Science Day events:

  • 10 a.m. to 4 p.m. – Open house and tours of the Hatfield Marine Science Center, hosted by Oregon Sea Grant and the U.S. Fish and Wildlife Service;
  • 11 a.m. and 2 p.m. – “Pumped up for Pinnipeds,” an presentation in the Visitor’s Center Auditorium by the Oregon Coast Aquarium for children and others interested in seals and sea lions;
  • 1 p.m. – A feeding of the octopus in the HMSC Visitors Center;
  • 3 to 4 p.m. – “Buy a Fish, Save a Tree,” a presentation in the Visitor’s Center Auditorium by Tim Miller-Morgan of OSU on fish health management and sustainable ornamental fisheries.

More information on Marine Science Day can be found at: http://hmsc.oregonstate.edu/marinescienceday/

Media Contact: 
Source: 

Maryann Bozza, 541-867-0234; maryann.bozza@oregonstate.edu

Multimedia Downloads
Multimedia: 

octopus

Study: Past warming increased snowfall on Antarctica, affecting global sea level

CORVALLIS, Ore. – A new study confirms that snowfall in Antarctica will increase significantly as the planet warms, offsetting future sea level rise from other sources – but the effect will not be nearly as strong as many scientists previously anticipated because of other, physical processes.

That means that many computer models may be underestimating the amount and rate of sea level rise if they had projected more significant impact from Antarctic snow.

Results of the study, which was funded by the National Science Foundation, were reported this week in the journal Nature Climate Change.

Scientists have long suspected that snowfall in Antarctica increases during planetary warming and the impact of so much snow tied up on land would have a negative effect on global sea levels. However, computer models on what should happen during warm periods have not matched observational data, according to Peter Clark, an Oregon State University paleoclimatologist and co-author on the study.

“Intuitively, it makes sense that as it warms and more moisture is in the atmosphere, that it will fall as snow in Antarctica,” Clark said. “The problem is that we’re not really seeing that through the last 50 years of observations – and documenting the relationship between changes in temperature and snow accumulation is difficult to do because of such strong natural variability.”

So Clark and his colleagues looked to the past to examine ice core data to see what they could learn about the future. They found that ice cores taken from the Antarctic Ice Sheet captured snow accumulation over time – and they could match that accumulation with established temperature data. They focused on a period from 21,000 years ago to 10,000 years ago – when the Earth gradually came out of the last ice age.

What they found was that Antarctica warmed an average of 5 to 10 degrees (Celsius) during that period – and for every degree of warming, there was a 5 percent increase in snowfall.

“The additional weight of the snow would have increased the ice flow into the ocean offsetting some of the limiting effect on sea level rise,” said Katja Frieler, a climatologist at the Potsdam Institute for Climate Impact Research in Germany and the lead author of the study. “It’s basic ice physics.”

The scientists found that the ice core results agreed with projections from three dozen computer models used to calculate future changes in snowfall. The end result, Clark said, is that projected increasing snowfall will still have a limiting effect on sea level rise, but that impact will be some 20 percent less than previously expected.

“Looking at the past gives us more confidence in anticipating what will happen in the future,” Clark noted. “The validation through ice core studies helps ground truth the computer models.”

Clark, a professor in Oregon State’s College of Earth, Ocean, and Atmospheric Sciences, was coordinating lead author on sea level change for the fifth Intergovernmental Panel on Climate Change report.

Other researchers involved in the study are from the Potsdam Institute for Climate Impact Research in Germany; the University of Wisconsin-Madison, Utrecht University in The Netherlands, and the University of Potsdam.

Media Contact: 
Source: 

Peter Clark, 541-737-1247; clarkp@geo.oregonstate.edu

New research reveals low-oxygen impacts on West Coast groundfish

CORVALLIS, Ore. – When low-oxygen “dead zones” began appearing off the Oregon Coast in the early 2000’s, photos of the ocean floor revealed bottom-dwelling crabs that could not escape the suffocating conditions and died by the thousands.

But the question everyone asked was, “What about the fish?” recalls Oregon State University oceanographer Jack Barth.

“We didn’t really know the impacts on fish,” Barth said. “We couldn’t see them.”

Scientists from NOAA Fisheries’ Northwest Fisheries Science Center and Oregon State have begun to answer that question with a new paper published in the journal Fisheries Oceanography. The paper finds that low-oxygen waters projected to expand with climate change create winners and losers among fish, with some adapted to handle low-oxygen conditions that drive other species away.

Generally the number of fish species declines with oxygen levels as sensitive species leave the area, said Aimee Keller, a fisheries biologist at the Northwest Fisheries Science Center and lead author of the new paper. But a few species such as Dover sole and greenstriped rockfish appear largely unaffected.

“One of our main questions was, ‘Are there fewer species present in an area when the oxygen drops?’ and yes, we definitely see that,” Keller said. “As it goes lower and lower you see more and more correlation between species and oxygen levels.”

Deep waters off the West Coast have long been known to be naturally low in oxygen. But the new findings show that the spread of lower oxygen conditions, which have been documented closer to shore and off Washington and California, could redistribute fish in ways that affect fishing fleets as well as the marine food chain.

The lower the oxygen levels, for example, the more effort fishing boats will have to invest to find enough fish. “We may see fish sensitive to oxygen levels may be pushed into habitat that’s less desirable and they may grow more slowly in those areas,” Keller said.

Researchers examined the effect of low-oxygen waters with the help of West Coast trawl surveys conducted every year by the Northwest Fisheries Science Center to assess the status of groundfish stocks. They developed a sturdy, protective housing for oxygen sensors that could be attached to the trawl nets to determine what species the nets swept up in areas of different oxygen concentrations.

The study combined the expertise of fisheries scientists such as Keller who assess fish stocks with oceanographers such as Barth who track ocean conditions to look at the relationship between the two.

“Initially, we would tell them where the low oxygen was, and they would trawl within areas ranging from low to high oxygen,” explained Barth, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “Later, oxygen sensors were deployed on all tows during the groundfish survey. They would look at the catch and the species richness.

“We tried to get it down to the individual species level, where we could tell which fish correlated with which oxygen levels.”  

Low-oxygen waters appear off the West Coast in two ways, Barth said. The first is the eastward movement of deep, oxygen-poor water that laps up against the West Coast. The second occurs when wind-driven upwelling brings nutrients to the surface, fueling blooms of phytoplankton that eventually die and sink to the bottom. Their decay then consumes the oxygen, leaving what scientists call hypoxic conditions where oxygen levels are low enough to adversely affect marine organisms.

The scientists examined the effects of varying oxygen levels on four representative species: spotted ratfish, petrale sole, greenstriped rockfish and Dover sole.

Spotted ratfish and petrale sole were the most sensitive to changes in oxygen levels, with their presence declining sharply as the amount of oxygen dissolved in the water declines. But greenstriped rockfish and Dover sole were largely unaffected by dissolved oxygen levels.

Dover sole is adapted to low-oxygen waters, with gill surface areas two to three times larger than other fish of similar size that allow it to absorb more oxygen from the same amount of water. Dover sole also are among a few fish species that can reduce their oxygen consumption to very low concentrations, probably an adaptation to low-oxygen conditions.

The research is continuing, with trawl survey vessels carrying oxygen sensors on all of their tows since 2009, Keller said. Further data should provide insight into the response of additional fish species to low oxygen conditions, Keller said.

Media Contact: 

Michael Milstein, NOAA Fisheries, 503-231-6268

Mark Floyd, OSU, 541-737-0788

Source: 

Jack Barth, 541-737-1607, barth@coas.oregonstate.edu

Warm winter wraps up – concern about low snowpack continues

CORVALLIS, Ore. – If it seemed like Oregon has had a lot of unseasonably warm days this winter, well, it’s because we have. Now the focus is on a very low snowpack – and the implications that may have later this year.

The meteorological winter – which is comprised of December, January and February – recently wrapped up and depending on where you live in Oregon, it was one of the warmest – if not the warmest – winters on record.

“It has been a very, very warm winter – almost historically so,” said Philip Mote, director of the Oregon Climate Change Research Institute at Oregon State University. “On one hand, the warm temperatures have made for a rather pleasant winter. On the other hand, the snowpack situation has been atrocious, and that really raises concerns for water levels in many streams later this summer.”

The National Oceanic and Atmospheric Administration’s seasonal outlook calls for “significantly enhanced likelihood” for a warm spring – especially in western Oregon and western Washington – and a “somewhat reduced likelihood” for a wet spring.

“That’s not a hopeful outlook for the kind of late recovery of snowpack that we have seen in some previous low-snow winters,” Mote noted.

How warm has this winter been? Mote said that each winter month was warmer than average at almost every recording station in Oregon. More than a hundred high temperature records were broken in Oregon – just in December. Another 114 high temperature records were broken in February.

Overall, Mote said, this should go down as the second warmest winter for the Pacific Northwest behind 1933-34, according to data from NOAA’s National Climatic Data Center. That was the Dust Bowl era - and 2014-15 wasn’t far behind. NOAA reports that parts of eastern and southern Oregon were more than eight degrees warmer than average for the meteorological winter.

Along the coast, temperatures in some places reached the low 70s, amazingly mild for mid-February.

In many other places in western Oregon, temperatures in the 60s were not uncommon. In fact, Roseburg reported 12 days of 60-degree-plus temperatures in February alone, according to National Weather Service data.

Although temperatures were warm, it wasn’t unusually dry, Mote said.

“The precipitation levels were unremarkable – just a bit lower than usual,” he pointed out. “However, a lot more of the precipitation fell as rain instead of snow – and that could have a major impact down the road. California, Oregon and Washington hardly have any snow – less than 10 percent of normal in some basins.”

On a regional basis, the winter temperatures looked like this:

  • Astoria: December was 4.4 degrees warmer than average; January was 2.5 degrees warmer; and February was 5.1 degrees warmer.
  • Eugene was 4.6 degrees warmer than average in December, 2.9 degrees warmer in January, and 5.3 degrees in February. Eugene reached a high of 62 degrees in December, 68 in January (a record for the month), and 65 in the month of February, which had five days of temperatures in the 60s.
  • McMinnville recorded a record high temperature of 66 degrees on Feb. 17, breaking the old mark of 65 set in 1996.
  • Portland was 3.7 degrees warmer than average in December, 2.0 degrees warmer in January, and 5.4 degrees warmer in February. The Rose City had seven days of 60-degree-plus weather in February alone.
  • Roseburg was 6.1 degrees warmer than average in December, 3.5 degrees warmer than average in January, and 4.8 degrees warmer than average in February. Roseburg had a total of 12 days of temperatures in the 60s in February.
  • Pendleton wasn’t as warm as the rest of the state early in the winter, but February was 5.5 degrees warmer than average and Pendleton recorded a high of 66 degrees on Feb. 6.
  • Salem set a new record high for February on Feb. 16, when the mercury reached 66 degrees, breaking the old record of 65 set in 1902.

More weather information is available on the Oregon Climate Change Research Institute website at: http://occri.net/. The institute is housed in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

Media Contact: 
Source: 

Phil Mote, 541-913-2274; pmote@coas.oregonstate.edu

Multimedia Downloads
Multimedia: 

 

 

 

 

 

 

 

 

 

 

 

A barefoot toddler at the Oregon Coast in January reflects the warm winter in the Northwest this year. (photo by Theresa Hogue)

2321stickview