OREGON STATE UNIVERSITY

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Mariana Trench: Seven miles deep, the ocean is still a noisy place

NEWPORT, Ore. – For what may be the first time, scientists have eavesdropped on the deepest part of the world’s oceans and instead of finding a sea of silence, they discovered a cacophony of sounds both natural and caused by humans.

For three weeks, a titanium-encased hydrophone recorded ambient noise from the ocean floor at a depth of more than 36,000 feet in a trough known as Challenger Deep in the fabled Mariana Trench near Micronesia. The team of researchers from the National Oceanic and Atmospheric Administration, Oregon State University and the U.S. Coast Guard expected to hear little. They were surprised.

“You would think that the deepest part of the ocean would be one of the quietest places on Earth,” said Robert Dziak, a NOAA research oceanographer and chief scientist on the project. “Yet there really is almost constant noise from both natural and man-made sources. The ambient sound field at Challenger Deep is dominated by the sound of earthquakes, both near and far was well as the distinct moans of baleen whales and the overwhelming clamor of a category 4 typhoon that just happened to pass overhead.

“There was also a lot of noise from ship traffic, identifiable by the clear sound pattern the ship propellers make when they pass by,” added Dziak, who has a courtesy appointment in Oregon State’s College of Earth, Ocean, and Atmospheric Sciences. “Guam is very close to Challenger Deep and is a regional hub for container shipping with China and The Philippines.”

The project, which was funded by the NOAA Office of Ocean Exploration and Research, was designed to establish a baseline for ambient noise in the deepest part of the Pacific Ocean. Anthropogenic, or human-caused noise has increased steadily over the past several decades and getting these first recordings will allow scientists in the future to determine if the noise levels are growing.

Getting those first sounds wasn’t easy.

The bottom of the Challenger Deep trough is roughly seven miles below the ocean’s surface. In fact, you could put the world’s tallest peak – Mount Everest – in the trench and its top would still be more than a mile from the surface.

The pressure at that depth is incredible, said Haru Matsumoto, an Oregon State ocean engineer who along with NOAA engineer Chris Meinig helped to develop a hydrophone capable of withstanding such pressure. In the average person’s home or office, the atmospheric pressure is about 14.7 pounds per square inch; at the bottom of the Mariana Trench, it is more than 16,000 PSI.

“We had never put a hydrophone deeper than a mile or so below the surface, so putting an instrument down some seven miles into the ocean was daunting,” Matsumoto said. “We had to drop the hydrophone mooring down through the water column at no more than about five meters per second. Structures don’t like rapid change and we were afraid we would crack the ceramic housing outside the hydrophone.”

Partnering with the U.S. Coast Guard, the researchers deployed the hydrophone from the Guam-based cutter Sequoia in July 2015. It took more than six hours for the instrument package to free-fall to the bottom of the Mariana Trench. Its recordings filled the flash drive in about 23 days, but the researchers had to wait until November to retrieve the hydrophone because of ships’ schedules and persistent typhoons.

Once back on site, they recovered the hydrophone mooring by sending an acoustic signal from the ship above, triggering its release from the seafloor. Attached floats allowed it to gradually ascend to the surface.

“It is akin to sending a deep-space probe to the outer solar system,” Dziak said. “We’re sending out a deep-ocean probe to the unknown reaches of inner space.”

For the past several months, Dziak and his colleagues have been analyzing the sounds and differentiating natural sounds from ships and other human activities.

“We recorded a loud magnitude 5.0 earthquake that took place at a depth of about 10 kilometers (or more than six miles) in the nearby ocean crust,” Dziak said. “Since our hydrophone was at 11 kilometers, it actually was below the earthquake, which is really an unusual experience. The sound of the typhoon was also dramatic, although the cacophony from big storms tends to be spread out and elevates the overall noise for a period of days.”

Matsumoto said the hydrophone also picked up a lot of noise from the surface of the ocean – some seven miles above – including waves and winds disturbing the surface.

“Sound doesn’t get as weak as you think it does even that far from the source,” he said.

Another OSU co-investigator on the project, Joe Haxel, will lead a planned return to Challenger Deep in 2017, where the researchers will deploy the hydrophone for a longer period of time and attach a deep-ocean camera.

Dziak, Matsumoto and Haxel are affiliated with the Acoustics Program in the NOAA/Pacific Marine Environmental Laboratory and work at OSU’s Hatfield Marine Science Center in Newport, Ore. The project in Challenger Deep is one of a number of projects in which the U.S. Coast Guard partners with NOAA to sponsor scientific research.

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Bob Dziak, 541-867-0175, Robert.P.Dziak@noaa.gov;

Haru Matsumoto, 541-867-0272; haru.matsumoto@oregonstate.edu

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A link to sound files, images and a video can be found at: http://bit.ly/1QSb8Mv

 

 

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Scientists say window to reduce carbon emissions is small

CORVALLIS, Ore. – At the rate humans are emitting carbon into the atmosphere, the Earth may suffer irreparable damage that could last tens of thousands of years, according to a new analysis published this week.

Too much of the climate change policy debate has focused on observations of the past 150 years and their impact on global warming and sea level rise by the end of this century, the authors say. Instead, policy-makers and the public should also be considering the longer-term impacts of climate change.

“Much of the carbon we are putting in the air from burning fossil fuels will stay there for thousands of years – and some of it will be there for more than 100,000 years,” said Peter Clark, an Oregon State University paleoclimatologist and lead author on the article. “People need to understand that the effects of climate change on the planet won’t go away, at least not for thousands of generations.”

The researchers’ analysis is being published this week in the journal Nature Climate Change.

Thomas Stocker of the University of Bern in Switzerland, who is past-co-chair of the IPCC’s Working Group I, said the focus on climate change at the end of the 21st century needs to be shifted toward a much longer-term perspective.

“Our greenhouse gas emissions today produce climate-change commitments for many centuries to millennia,” said Stocker, a climate modeler and co-author on the Nature Climate Change article. “It is high time that this essential irreversibility is placed into the focus of policy-makers.

“The long-term view sends the chilling message (about) what the real risks and consequences are of the fossil fuel era,” Stocker added. “It will commit us to massive adaptation efforts so that for many, dislocation and migration becomes the only option.”

Sea level rise is one of the most compelling impacts of global warming, yet its effects are just starting to be seen. The latest IPCC report, for example, calls for sea level rise of just one meter by the year 2100. In their analysis, however, the authors look at four difference sea level-rise scenarios based on different rates of warming, from a low end that could only be reached with massive efforts to eliminate fossil fuel use over the next few decades, to a higher rate based on the consumption of half the remaining fossil fuels over the next few centuries.

With just two degrees (Celsius) warming in the low-end scenario, sea levels are predicted to eventually rise by about 25 meters. With seven degrees warming at the high-end scenario, the rise is estimated at 50 meters, although over a period of several centuries to millennia.

“It takes sea level rise a very long time to react – on the order of centuries,” Clark said. “It’s like heating a pot of water on the stove; it doesn’t boil for quite a while after the heat is turned on – but then it will continue to boil as long as the heat persists. Once carbon is in the atmosphere, it will stay there for tens or hundreds of thousands of years, and the warming, as well as the higher seas, will remain.”

Clark said for the low-end scenario, an estimated 122 countries have at least 10 percent of their population in areas that will be directly affected by rising sea levels, and that some 1.3 billion – or 20 percent of the global population – live on lands that may be directly affected. The impacts become greater as the warming and sea level rise increases.

“We can’t keep building seawalls that are 25 meters high,” noted Clark, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “Entire populations of cities will eventually have to move.”

Daniel Schrag, the Sturgis Hooper Professor of Geology at Harvard University, said there are moral questions about “what kind of environment we are passing along to future generations.”

“Sea level rise may not seem like such a big deal today, but we are making choices that will affect our grandchildren’s grandchildren – and beyond,” said Schrag, a co-author on the analysis and director of Harvard’s Center for the Environment. “We need to think carefully about the long time-scales of what we are unleashing.”

The new paper makes the fundamental point that considering the long time scales of the carbon cycle and of climate change means that reducing emissions slightly or even significantly is not sufficient. “To spare future generations from the worst impacts of climate change, the target must be zero – or even negative carbon emissions – as soon as possible,” Clark said.

“Taking the first steps is important, but it is essential to see these as the start of a path toward total decarbonization,” Schrag pointed out. “This means continuing to invest in innovation that can someday replace fossil fuels altogether. Partial reductions are not going to do the job.”

Stocker said that in the last 50 years alone, humans have changed the climate on a global scale, initiating the Anthropocene, a new geological era with fundamentally altered living conditions for the next many thousands of years.

“Because we do not know to what extent adaptation will be possible for humans and ecosystems, all our efforts must focus on a rapid and complete decarbonization –the only option to limit climate change,” Stocker said.

The researchers’ work was supported by the U.S. National Science Foundation, the U.S. Department of Energy, the Natural Sciences and Engineering Research Council of Canada, the German Science Foundation and the Swiss National Science Foundation.

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

Thomas Stocker, +41 31 631 44 62, stocker@climate.unibe.ch;

Daniel Schrag, 617-233-2554, schrag@eps.harvard.edu

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Rising sea levels will threaten residents of many countries.

Study: Fish assemblages can change rapidly along coast as water warms

CORVALLIS, Ore. – A modest warming of coastal waters can have a significant impact on juvenile fish assemblages in a period of just a few years, a newly published study has found, raising concern about the potential effects of climate change.

Such a shift is taking place on the Skagerrak coast of Norway, where more warm-water fish species have begun appearing over the past two decades while many populations of resident cold-water fish species have declined.

Results of the study have just been published in the journal Global Change Biology.

Studying the potential impact of climate change on coastal fishes has been difficult, researchers say, because few long-term records adequately address species diversity. But researchers at Norway’s Institute of Marine Research have been conducting what has to be one of the longest, most consistent surveys of near-shore waters ever undertaken – a key to understanding climate change effects.

“What we’re seeing is a clear influence of ocean temperature on the region’s juvenile fish community, which has changed in what is a very important fish nursery area,” said Caren Barceló, an Oregon State University doctoral candidate and lead author on the study. “It has implications for nursery habitats that have been around for decades.”

Barceló, who worked with Norwegian researchers on their beach seine surveys, said no new species had appeared in the waters of Skagerrak for nearly three decades beginning in the mid-1960s. Within the next 15 years, however, several pelagic, planktivorou species more characteristic of the Mediterranean arrived – for example, European anchovy (Engraulis encrasicolus) and European pilchard (Sardina pilchardus).

Other warm-water species of fish present now were documented once before in the area, such as juvenile horse mackerel (Trachurus trachurus), when the water warmed in the 1930s and ‘40s and then became less prevalent when it cooled. The corkwing wrasse (Symphodus melops) is another fish species that appeared during the earlier warm period, then became less prevalent for more than half a century – before returning during the latest warming.

Cold-water species that have been caught less frequently in this dataset over the past two decades include cod (Gadus morhua), pollack (Pollachius pollachius), and European eel (Anguilla anguilla).

One concern, the researchers say, is that the present warming is not an anomaly, rather a symptom of climate change that may worsen instead of going away. There may be other factors involved in the introduction of new species, noted Lorenzo Ciannelli, an Oregon State marine ecologist and co-author on the study.

“There are some unique elements happening today that distinguish the situation from the 1930s and ‘40s,” Ciannelli said. “Winds and currents are pushing warm water into the area in such a way that it suggests the pattern might be here to stay.

“Some fish will move into a new area as adults, while other species disperse their eggs or larva and they then ride into new regions on the currents,” he added. “To make them ‘stick’ there may need to be a seeding process that allows the local population to develop.”

The key to understanding the assemblage shift in Norway is the extraordinary data set collected by Norwegian researchers. For the past 96 years, they have conducted an extensive coast-wide seine survey during the last two weeks of September, using the same style boats, the same locations and nets that were exactly the same size.

Only five survey leaders have coordinated the effort over 96 years, each one having trained with the previous leader for at least 10 years on the operation of setting and hauling the beach seine before taking over the project themselves.

“It began as a project to analyze the recruitment of juvenile cod in the region,” Barceló said, “but someone had the foresight a century ago to document all of the species  brought up in the nets – and they’ve kept it up ever since.”

Barceló, who worked with the Norwegians over two summers, is also analyzing fish surveys off the Oregon coast, investigating the long-term environmental variability and shifting marine fish assemblages.

She and Ciannelli are in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

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Caren Barceló, 541-737-3965, caren.barcelo@gmail.com;

Lorenzo Ciannelli, 541-737-3142, lciannelli@coas.oregonstate.edu

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Caren Barcelo works with Norwegian researchers.

2015 goes down as the warmest in Oregon history

CORVALLIS, Ore. – A mild winter, an early spring and warmer-than-average temperatures every season have contributed to a record-breaking year, as 2015 will go down as the warmest in Oregon since state records began in 1895.

Oregon’s previous record high average temperature of 49.9 degrees was set in 1934 – the height of the Dust Bowl – when the entire country was plagued by hot, dry weather.

Despite a cold, icy end to December in Oregon, the average temperature in 2015 was 50.4 degrees, not only a record but far above the average yearly temperature for the 20th century, which was 47.8 degrees, according to Oregon State University’s Philip Mote, who directs the Oregon Climate Change Research Institute on campus.

“In previous years, we’ve had periods where the weather was warmer for differing spells,” Mote said. “In 2015, though, it was warmer than average almost all the way through the year.” A combination of meteorological conditions and greenhouse gases led to the record warm year, he added.

The statistics are from the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information.

Oregon was not alone in experiencing a warm 2015, according to Kathie Dello, deputy director of the Oregon Climate Service at OSU. Washington, Montana and Florida also experienced record high temperatures, and in several other states 2015 went down in the top five of all time.

It appears this will be yet another record warm year for average global temperature, Dello pointed out, and it is officially the second warmest year in the United States, despite blizzards and Arctic temperatures in the Northeast.

“If you are 31 years of age, you have not lived through a single month in which the global temperature was below average,” Dello said. “And if you are 31 and living in Oregon, you have only experienced three years here that were cooler than the 20th-century average.”

Researchers calculate the average temperature for each day by looking at the highest and lowest temperatures. If the high reaches 90 degrees and the low is 60, that day’s average temperature is 75 degrees. They then calculate the average monthly temperature, and finally, the average yearly temperature.

The average for the state is done by analyzing temperatures at a series of long-established weather stations throughout the state.

 “We had a ridge of high pressure that set up and kept the weather warm and dry throughout most of the summer and fall,” Mote said. “That followed a winter in which we got nearly average precipitation, but much of it came from the south and it fell as rain instead of snow.”

Mote said the record-setting 2015 weather was a combination of meteorological phenomena and the Earth gradually getting warmer because of human activities.

Through rigorous statistical analysis, scientists are able to tease out the impacts of El Niño, greenhouse gas emissions, volcanic activity and solar activity on temperatures. Mote said 2015 would have been a warm year because of meteorological conditions, but the 1-2 degrees (F) attributable to greenhouse gases pushed temperatures into record territory.

“There’s little doubt that the insulation of the planet from greenhouse gas emissions played a role in the warming throughout the year,” he said.

The OSU researchers say expect more of the same in 2016.

“With El Niño and the remnants of The Blob (a huge warm patch of water in the North Pacific Ocean), it should be another warm year for the Earth, and for Oregon,” Dello said.

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Phil Mote, 541-737-5694, pmote@coas.oregonstate.edu;

Kathie Dello, 541-737-8927, kdello@coas.oregonstate.edu

 

 

 

 

 

A 72-degree day in January (2015) at Yachats on the Oregon Coast. (photo by Theresa Hogue)

OSU/NOAA study: Warm-water years are tough on juvenile salmon

NEWPORT, Ore. – A new analysis of juvenile Chinook salmon in the Pacific Ocean documents a dramatic difference in their foraging habits and overall health between years of warm water and those when the water is colder.

The study found that when the water is warmer than average – by only two degrees Celsius – young salmon consume 30 percent more food than during cold-water regimes. Yet they are smaller and skinnier during those warm-water years, likely because they have to work harder to secure food and the prey they consume has less caloric energy.

Results of the research, conducted by researchers from Oregon State University and the National Oceanic and Atmospheric Administration, are being published this week in the journal PLOS One.

“When young salmon come out to sea and the water is warm, they need more food to keep their metabolic rate up, yet there is less available food and they have to work harder,” said Elizabeth Daly, an Oregon State senior faculty research assistant with the Cooperative Institute for Marine Resources Studies, a joint program of OSU and NOAA.

“Our long-term data set contradicts the long-held assumption that salmon eat less during warm-water regimes,” Daly added. “They actually eat more. But they still don’t fare as well. When the water is warm, salmon are smaller and thinner.”

Daly teamed with Richard Brodeur, a NOAA Northwest Fisheries Science Center researcher, to examine 19 years of juvenile salmon surveys, from 1981-85 and 1998-2011. The rich, long-term data set revealed the trophic habits, size and condition of yearling Chinook salmon caught soon after they migrated to the ocean. The researchers found that during both warm- and cold-water regimes, the diet of the salmon is primarily fish, but when the water is cold, they also consume more lipid-rich krill and Pacific sand lance. When the water is warmer, the salmon’s diet had more juvenile rockfish and crab larvae.

Previous research led by Bill Peterson, a NOAA fisheries biologist and courtesy professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences (CEOAS), found that the makeup of copepods during cold-water years differs greatly than during warm-water years. In cold years, these small crustaceans drift down from the north and are lipid-rich, with much higher nutrient levels than copepods from the south.

And though salmon may not directly consume these copepods, they are eating the fish that do consume them, noted Brodeur, also a courtesy faculty member in CEOAS.

“The warm years typically have less upwelling that brings the cold, nutrient-rich water to the surface,” Brodeur said. “Or in the case of 2005, the upwelling was so late that many of the salmon died because there was no food when they entered the ocean.”

“Salmon populations may be able to handle one year of warm temperatures and sparse food,” Brodeur added. “But two or three years in a row could be disastrous – especially for wild fish populations. They may have to travel much farther north to find any food.”

Hatchery-raised salmon that are released in similar numbers in warm- or cold-water years may fare slightly better during bad ocean conditions, the researchers noted, because they tend to be larger when they enter the marine environment.

Daly and Brodeur, who work out of OSU’s Hatfield Marine Science Center in Newport, Oregon, said that the 19 survey years they analyzed included 10 warm-water years and nine cold-water years. In some cases, the warm water was a result of an El Niño, while in other years it was a lack of upwelling.

During the last two years, an unusually large, warm body of water has settled into the ocean off the Pacific Northwest that scientists have dubbed “The Blob,” which is forecast to be followed this winter by a fairly strong El Niño event. Though recent spring Chinook salmon runs have been strong due to cooler ocean conditions in 2012-13, the impact of this long stretch of warm water on juvenile fish may bode poorly for future runs.

“So far this year, we’ve seen a lot of juvenile salmon with empty stomachs,” Daly said. “The pressure to find food is going to be great. Of those fish that did have food in their stomachs, there was an unusual amount of juvenile rockfish and no signs of Pacific sand lance or krill.

“Not only does this warm water make it more difficult for the salmon to find food, it increases the risk of their own predation as they spend more time eating and less time avoiding predators,” she added.

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Elizabeth Daly, 541-867-0404; elizabeth.daly@oregonstate.edu;

Ric Brodeur, 541-867-0335, Richard.Brodeur@noaa.gov

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72 scientists ink letter to U.S. presidential candidates urging leadership on clean energy

CORVALLIS, Ore. – A group of 72 leading climate change scientists have written a letter to major United States presidential candidates urging strong American leadership on clean energy – and calling for a “vibrant economy free from carbon pollution by mid-century.”

The effort began as a letter from nine scientists from Harvard University, Stanford University, University of California at Berkeley, Tufts and elsewhere – part of the Union of Concerned Scientists. Other scientists, including Philip Mote of Oregon State University, recently joined the initiative.

Mote, who directs the Oregon Climate Change Research Institute at Oregon State, and also provides leadership on two joint federal climate change centers at the university, said focusing on clean, renewable sources of energy is not a choice between a strong economy and a healthy environment.

“These are not mutually exclusive,” said Mote, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “Many of the largest and most influential companies in the world are using energy from renewable sources, including Apple, Google and others. It’s not just a good environmental strategy – they see it as a good business strategy.”

“Oregon’s emission of greenhouse gases peaked in 1999 and has been declining, showing that we can grow the economy and reduce emissions,” Mote added.

In their letter, the climate scientists point to the gradual shift away from non-sustainable fossil fuels to solar and wind power – in part because of rapidly advancing technology. The next U.S. president “will be uniquely positioned to ensure that our nation sustains and accelerates this transition,” they wrote. “The dangers of inaction are also increasingly apparent and lend great urgency to this appeal.”

The letter is being released this week as policy-makers and others convene in Paris for the annual international climate summit.  Limiting carbon emissions from fossil fuels is critical in slowing the rate of warming the Earth is experiencing, the scientists note, and the effects are being seen world-wide – from rapidly warming and acidifying oceans to melting glaciers.

Yet much of the public – and many political leaders – has been slow to accept what many scientists say is overwhelming evidence that our planet is in peril, Mote said.

“This week, as some of Oregon’s rivers are rising, we are reminded that a warming climate accentuates existing risks like flooding,” Mote said.  “Additional risks for the region include increased wildfires and coastal inundation. Limiting emissions will reduce the size of future changes."

The scientists call for the next president to pursue key goals, including:

  • Following through on the U.S. commitment to reduce carbon emissions by 26 to 28 percent below 2005 levels by the year 2025;
  • Phasing out fossil energy subsidies and putting a price on carbon to “ensure a level playing field” for renewable energy, nuclear power and other low- or zero-carbon technologies;
  • Modernizing antiquated energy transmission, distribution and transportation systems;
  • Increasing investment in clean energy research.

Mote was a lead author on the 2007 Intergovernmental Panel on Climate Change report, which led to a Nobel Prize, and a lead author for the fifth IPCC report in 2013 in a chapter focusing on the cryosphere.

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Phil Mote, 541-737-5692, pmote@coas.oregonstate.edu

Report: Willamette Valley water future mostly bright, though gaps may need to be addressed

CORVALLIS, Ore. – During the next 85 years, temperatures in Oregon’s Willamette River basin are expected to rise significantly, mountain snowpack levels will shrink dramatically, and the population of the region and urban water use may double – but there should be enough water to meet human needs, a new report concludes.

Fish may not be so lucky. Although ample water may be available throughout most of the year, the Willamette Valley and its tributaries likely will become sufficiently warm as to threaten cold-water fish species, including salmon and steelhead, the scientists say.

These are among the key findings of the Willamette Water 2100 Project, a five-year, $4.3 million study funded by the National Science Foundation and led by Oregon State University, in partnership with researchers from the University of Oregon, Portland State University and University of California at Santa Barbara.

“The Willamette River basin today is characterized by abundant annual water and sometime seasonal shortages,” said Anne Nolin, an OSU professor of environmental sciences and principal investigator on the study. “That should continue into 2100, despite much warmer temperatures, more people and a substantial loss of snowpack.

“The reason for optimism is the region’s 11 storage reservoirs coordinated by the Army Corps of Engineers that act as a valve for seasonal differences and preserve water for times of need,” Nolin added. “Without them, the picture would look quite a bit different.”

Analysis of global circulation models suggest that the Willamette River basin will warm between two and 13 degrees (Fahrenheit) by the year 2100, thus scientists used three separate scenarios to look at potential impacts based on low, medium and high rates of temperature increase. These temperature increases will result in a dramatic decline in snowpack – from 63 to 95 percent lower than average – changing seasonal water flow patterns.

Scientists also explored results from a range of population, economic and policy scenarios that allowed them to ask “what if?” questions for different human changes and interactions with climate changes. Much of the climate modeling for the project was developed through a regional integrated sciences and assessments (RISA) program at Oregon State, which is funded by NOAA and led by OSU Professor Philip Mote.

There is little doubt that temperatures will increase, the report notes, but there is less certainty about the impact of a changing climate on precipitation. Winters may actually be slightly wetter, though more of the precipitation will fall as rain instead of snow. Summers should be drier, necessitating more reliance on water held behind the region’s 11 storage reservoirs.

“Although there are a number of government entities – federal and state – involved in regulating water use from those reservoirs, there appears to be enough flexibility in the system to adequately adapt for changing conditions in the future,” said Nolin, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

The report notes that warmer temperatures, less snowpack and drier summers will greatly increase the danger of wildfire in the mountains feeding the Willamette River basin – by about 200 to 900 percent. Their simulations show that fire will open up lands to new forest types and reduce the availability of forestland for timber harvest.

Increasing urban use of water from a population that could double will involve costly expansions in infrastructure. As the population grows, more agricultural land near urban areas will be developed for housing and other needs, according to Samuel Chan, a watershed health specialist with Oregon Sea Grant and the broader impacts outreach lead for the Willamette Water 2100 Project.

However, the report shows that in some cases where urban areas are expanding into what are now irrigated farmlands, these locations may see a net decline in water use.

“The report notes the difference between water ‘diversions’ and water ‘consumptive use,’” Chan noted. “As the population grows, the need for water will increase, but much of it will be used, and then treated in wastewater plants and returned to the system. Other uses, like forests and agriculture, consume the water through evaporation and transpiration to the atmosphere.”

“The downside, though, is that treated water that is returned to the river is often warmer, increasing the impact on cold-water fish species,” he added.

The main drivers for changing water needs, the report concludes, are climate change, and growth in population and income.

“The dams built above the Willamette Valley were engineered for reducing the risk of floods, but they also do a valuable job in storing water for use during summer,” Nolin said. “They can store large amounts of water in the summer, when they are not kept empty for flood prevention and there is existing flexibility in water allocation policies that could help western Oregon adapt to a climate that may be quite different in the future.”

“Unlike many parts of the country, those of us who live in the Willamette Valley are lucky because we have abundant water for human use, and we have institutional capacity to help mitigate water scarcity,” she added. “However, the biggest negative impacts are likely to be for native cold-water fish and we will likely be facing a significant challenge in managing stream temperature for fish.”

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Anne Nolin, 541-737-8051, nolina@geo.oregonstate.edu;

Sam Chan, (cell: 503-679-4828), Samuel.chan@oregonstate.edu

Blue whales use efficient foraging to maintain massive body size

CORVALLIS, Ore. – As the largest animals to have ever lived on Earth, blue whales maintain their enormous body size through efficient foraging strategies that optimize the energy they gain from the krill they eat, while also conserving oxygen when diving and holding their breath, a new study has found.

Large, filter-feeding whales have long been thought of as indiscriminate grazers that gradually consume copious amounts of tiny krill throughout the day – regardless of how prey is distributed in the ocean. But tagged blue whales in the new study revealed sophisticated foraging behavior that targets the densest, highest-quality prey, maximizing their energy gain.

Understanding blue whale feeding behavior will help inform protections for the endangered species and its recovery needs, the scientists say. The study, by researchers from NOAA Fisheries, Oregon State University and Stanford University, was published this week in Science Advances.

“For blue whales, one of our main questions has been: How do they eat efficiently to support that massive body size,” said Elliott Hazen, a research ecologist with NOAA Fisheries’ Southwest Fisheries Science Center and lead author of the research. “Now we know that optimizing their feeding behavior is another specialization that makes the most of the food available.”

Adult blue whales can grow to the length of a basketball court and weigh as much as 25 large elephants combined, but they operate on an “energetic knife-edge,” the researchers point out.  They feed through the extreme mechanism of engulfing as much prey-laden water as they weigh and then filtering out the tiny krill it contains.

But feeding expends tremendous amounts of energy and the dense krill patches they need to replenish that energy are often deep and difficult to find.

In their study, the researchers compared the foraging of 14 tagged blue whales to 41 previously tagged blue whales off the coast of California, combining the data with acoustic surveys that measured the density of their sole prey, krill – tiny (less than one inch) crustaceans found throughout the world’s oceans.

The researchers found that when the krill were spread out, or less dense, blue whales fed infrequently to conserve their oxygen and energy use for future dives. When krill density increased, they began “lunge-feeding” more frequently, consuming more per dive to obtain as much energy from the krill as possible.

“Blue whales don’t live in a world of excess and the decisions these animals make are critical to their survival,” said Ari Friedlaender, a principal investigator with the Marine Mammal Institute at Oregon State University’s Hatfield Marine Science Center and co-author on the study. “If you stick your hand into a full bag of pretzels, you’re likely to grab more than if you put your hand into a bag that only had a few pretzels.”

The feeding pattern that focuses more effort on the densest krill patches provides a new example of blue whale foraging specializations that support the animals’ tremendous size.

This kind of lunge-feeding takes a lot more effort, but “the increase in the amount of energy they get from increased krill consumption more than makes up for it,” noted Jeremy Goldbogen, a marine biologist from Stanford University and co-author on the study.

“Lunge-feeding is a unique form of ‘ram-feeding’ that involves acceleration to high speed and the engulfment of large volumes of prey-laden water, which they filter,” Goldbogen noted. “But we now know they don’t take in that water indiscriminately. They have a strategy that aims to focus feeding effort on the densest, highest-quality krill patches.”

In their study, the researchers found a threshold for krill that determined how intensively the blue whales fed.

“The magic number for krill seems to be about 100 to 200 individuals in a cubic meter of water,” Hazen said. “If it’s below that range, blue whales use a strategy to conserve oxygen and feed less frequently. If it’s above that, they’ll feed at very high rates and invest more effort.”

The researchers say this insight into blue whale feeding will help determine how best to protect the species, which is listed as endangered by the International Union for Conservation of Nature.

“If they are disturbed during the intense, deep-water feeding, it may not have consequences today, or this week, but it could over a period of months,” Friedlaender said. “There can be impacts on their overall health, as well as on their fitness and viability for reproduction.”

The study was funded by the U.S. Office of Naval Research.

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Ari Friedlaender, 919-672-0103

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Impacts of El Niño, La Niña on Pacific Ocean communities, beaches could expand in 21st century

CORVALLIS, Ore. – A coastal hazards analysis of 48 Pacific Ocean beaches in three continents, using data from 1979 to 2012, found the biggest factor influencing communities and beaches in all regions was the impact of El Niño and La Niña events.

The study also found their influence had alternate impacts in different parts of the Pacific basin. When one side of the Pacific experienced extreme coastal erosion and flooding because of El Niño the other side often experienced these hazards during La Niña. Some climate projections suggest that these events may occur more frequently in the 21st century, meaning that populated regions could experience more severe flooding or erosion.

Results of the study, which was funded by a variety of organizations, are being published this week in Nature Geoscience.

“There are many factors that can influence coastal vulnerability yet many future projections of coastal hazards focus only on sea level rise and  neglect the influence of seasonal water level anomalies, storm surges, wave-driven processes and other factors,” said Peter Ruggiero, an Oregon State University coastal hazards expert and co-author on the study.

“We knew that climate cycles play a major role in what happens to our coastlines, but the fact that El Niño and La Niña significantly affect coastal hazards throughout the Pacific in a fairly coherent manner was a bit of a surprise,” added Ruggiero, who is an associate professor of geology and geophysics in OSU’s College of Earth, Ocean and Atmospheric Sciences.

The analysis also confirmed what scientists had suspected – the most dominant impacts on beaches and communities through climate cycles takes place in the boreal (northern) winter. Some projections suggest that the worst-case scenarios for sea level rise could displace up to 187 million people by the end of the 21st century, with flood losses exceeding $1 trillion (in U.S. dollars) for the world’s major coastal cities.

More frequent, and potentially more severe, El Niño and La Niña events could worsen the situation.

The researchers also looked specifically at the Pacific Northwest of the United States, which experiences extreme water level anomalies during major El Niño events – on the order of tens of centimeters, and changes in both wave height and direction. Storms reaching the coast from more steep southern approach angles cause significant “hotspots” of erosion, Ruggiero pointed out.

“The El Niño winters of 1982-83 and 1997-98 resulted in the most extreme coastal flooding and erosion hazards along the Oregon and Washington coast in recent decades – oftentimes taking many years to recovery, if at all,” the authors wrote in their analysis.

In 2013, Ruggiero led a study of Pacific Northwest beaches that found Washington’s beaches, on average, were more stable than those in Oregon, which had experienced an increase in erosion hazards in recent decades. His study found that since the 1960s, 13 of the 17 Oregon beach “littoral cells” – stretches of beach between rocky headlands and major inlets – have either experienced an increase in erosion, or less of a buildup in sand during beach-building months.

Some of the hardest hit areas along the coast include the Neskowin littoral cell between Cascade Head and Pacific City, and the Beverly Beach littoral cell between Yaquina Head and Otter Rock, where shoreline change rates have averaged more than one meter of erosion a year since the 1960s.

“We’re in the midst of a strengthening El Niño right now,” Ruggiero said, “and we already seeing some significant water level anomalies through tide gauge readings. Some people project that this 2015-16 El Niño could match those significant events of 1982-83 and 1997-98.

“If we get significant storms this winter during times of elevated water levels, the region could experience erosion and hazards not seen in some years.”

 


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Peter Ruggiero, 541-737-1239; ruggierp@science.oregonstate.edu

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Erosion at the central Oregon coast.

OSU names Haggerty interim dean of college

CORVALLIS, Ore. – Roy Haggerty, the Hollis M. Dole Professor of Environmental Geology at Oregon State University, has been named interim dean of OSU’s College of Earth, Ocean, and Atmospheric Sciences.

He succeeds Mark Abbott, who earlier this summer accepted a position as president and director of Woods Hole Oceanographic Institution, effective Oct. 1. Oregon State will launch a national search for a new dean in September, according to Sabah Randhawa, OSU provost and executive vice president.

“I am delighted that Roy has agreed to serve as interim dean,” Randhawa said. “He is known as a leader with integrity and as a bridge builder, and his candidacy generated a great sense of enthusiasm across the College of Earth, Ocean, and Atmospheric Sciences.”

Haggerty has been on the OSU faculty since 1996 and served as head of the geology program from 2003-06 in the Department of Geosciences, before it was merged with the College of Oceanic and Atmospheric Sciences. With more than 100 faculty members and nearly a thousand graduate and undergraduate students the College of Earth, Ocean, and Atmospheric Sciences is one of the largest and strongest programs of its kind in North America.

An expert in hydrology, Haggerty’s research has addressed transport of nutrients, carbon and heat in streams, nuclear waste disposal issues in the United States and Sweden, and other forms of groundwater contamination.

In his two decades at OSU, his work has been supported by more than $9 million in grants and contracts from the National Science Foundation, the Department of Energy, the U.S. Environmental Protection Agency, the U.S.D.A. Forest Service and other organizations. He has taught at all levels, from introductory earth sciences to advanced classes in hydrology.

He is the principal investigator for the Willamette Water 2100 project, sponsored by the NSF, and involving 20 faculty members at OSU, University of Oregon, Portland State University and the University of California, Santa Barbara. The project seeks to understand how climate change, population growth and human activity may affect water scarcity in the Willamette Basin throughout the 21st century.

Haggerty is a graduate of the University of Alberta and has master’s and doctoral degrees in hydrogeology from Stanford University.

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Sabah Randhawa, 541-737-2111, Sabah.Randhawa@oregonstate.edu;

Roy Haggerty, 541-737-1210, roy.haggerty@oregonstate.edu

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    Interim dean Roy Haggerty