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Analyzing magma temperatures may help get closer to forecasting volcanic eruptions

CORVALLIS, Ore. – Although volcanic eruptions are often quite hazardous, scientists have been unable to pinpoint the processes leading up to major eruptions – and one important limitation has been a lack of knowledge about the temperature history of the magma.

A new study analyzed crystals of the mineral zircon – zirconium silicate – in magma from an eruption in the Taupo Volcanic Zone in New Zealand about 700 years ago to determine the magma’s history. The analysis shows the magma went through a comparatively “cool” period for thousands of years before heating up. Once magma temperatures reached 750 degrees Celsius, it was a short amount of time – decades or less – before an eruption occurred.

This pattern of long-term crystal storage in near-solid magma, punctuated by rapid heating, is applicable to many other volcanoes around the world, the researchers say, and may begin to help scientists recognize when a volcano is heading toward an eruptive phase.

Results of the research, which was supported by the National Science Foundation, are being reported this week in Science.

“Mobility in magma is a function of temperature and most of the time when it’s sitting there in the Earth’s crust under the volcano it’s cool,” said Adam Kent, an Oregon State University geologist and co-author on the study. “Of course, cool is a relative description since it’s still some 650 degrees (Celsius). I wouldn’t put my finger on it.

“But to erupt onto the Earth’s surface magma needs to heat up so it can be runny enough to be squeezed along cracks in the Earth and pushed up to the surface. At lower temperatures, the magma is too crystal-rich and viscous to move. It’s like trying to spread cold peanut butter onto a piece of bread. It takes higher temperatures to get things moving – and then our data show it’s only a period of years or decades before it erupts.”

Kent said the Taupo magma system has similarities to many volcanoes around the world, including the Cascade Range in the Pacific Northwest of the United States. A past study by Kent and his colleagues using a different approach found that Mount Hood in Oregon also spent most of its history in a cold, rigid state before moving rapidly into an eruptive phase.

This new study adds more certainty to the method and provides a new tool to apply this work to other volcanoes, the researchers say.

The key to honing in on these long-term geologic processes is understanding the volcanoes’ thermal or temperature history, according to the researchers. Past studies began making inroads into understanding the history of magma temperatures, but they relied on trying to reconcile data from a sample containing many thousands of individual crystals.

Using zircon crystals, which can be dated through analyzing the decay of uranium and thorium, adds more resolution, or precision, to the process. The crystals are like a “black box” flight recorder for studying volcanic eruptions, according to Kari Cooper of the University of California, Davis, corresponding author on the study.

“Instead of trying to piece together what happened from the wreckage,” Cooper said, “the crystals can tell us what was going on while they were below the surface, including the runup to an eruption.”

Zircon crystals occur in magma from many volcanoes and the new technique will have wide applications to volcanoes along the ring of fire – the belt of volcanoes that surround the Pacific Ocean – and elsewhere.

“It removes some uncertainty and gives us a great new tool to go back and look at other volcanoes,” Kent said.

The finding also suggests that if many volcanoes store their magma in this relatively cold state, recognizing volcanoes where warm and mobile magma is present may help researchers find volcanoes in the early throes of producing future eruptions. The technology to monitor volcanoes using seismic waves and other remote techniques is improving all the time, the researchers said.

The Science study was led by Allison Rubin and Cooper of the University of California at Davis. Other researchers included Christy Till and Maitrayee Bose of Arizona State University; Fidel Costa, Nanyang Technological University of Singapore; Darren Gravley and Jim Cole of the University of Canterbury in New Zealand; and Chad Deering, Michigan Technological University.

Kent is on the faculty of the College of Earth, Ocean, and Atmospheric Sciences at Oregon State.

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Mark Floyd, 541-737-0788

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Sediment from Himalayas may have made 2004 Indian Ocean earthquake more severe

CORVALLIS, Ore. – Sediment that eroded from the Himalayas and Tibetan plateau over millions of years was transported thousands of kilometers by rivers and in the Indian Ocean – and became sufficiently thick over time to generate temperatures warm enough to strengthen the sediment and increase the severity of the catastrophic 2004 Sumatra earthquake.

The magnitude 9.2 earthquake on Dec. 26, 2004, generated a massive tsunami that devastated coastal regions of the Indian Ocean. The earthquake and tsunami together killed more than 250,000 people making it one of the deadliest natural disasters in history.

An international team of scientists that outlined the process of sediment warming says the same mechanism could be in place in the Cascadia Subduction Zone off the Pacific Northwest coast of North America, as well as off Iran, Pakistan and in the Caribbean.

Results of the research, which was conducted as part of the International Ocean Discovery Program, are being published this week in the journal Science.

“The 2004 Indian Ocean tsunami was triggered by an unusually strong earthquake with an extensive rupture area,” said expedition co-leader Lisa McNeill, an Oregon State University graduate now at the University of Southampton. “We wanted to find out what caused such a large earthquake and tsunami, and what it might mean for other regions with similar geological properties.”

The research team sampled for the first time sediment and rocks from the tectonic plate that feeds the Sumatra subduction zone. From the research vessel JOIDES Resolution, the team drilled down 1.5 kilometers below the seabed, measured different properties of the sediments, and ran simulations to calculate how the sediment and rock behaves as it piles up and travels eastward 250 kilometers toward the subduction zone.

“We discovered that in some areas where the sediments are especially thick, dehydration of the sediments occurred before they were subducted,” noted Marta Torres, an Oregon State University geochemist and co-author on the study. “Previous earthquake models assumed that dehydration occurred after the material was subducted, but we had suspected that it might be happening earlier in some margins.

“The earlier dehydration creates stronger, more rigid material prior to subduction, resulting in a very large fault area that is prone to rupture and can lead to a bigger and more dangerous earthquake.”

Torres explained that when the scientists examined the sediments, they found water between the sediment grains that was less salty than seawater only within a zone where the plate boundary fault develops, some 1.2 to 1.4 kilometers below the seafloor.

“This along with some other chemical changes are clear signals that it was an increase in temperature from the thick accumulation of sediment that was dehydrating the minerals,” Torres said.

Lead author Andre Hüpers of the University of Bremen in Germany said that the discovery will generate new interest in other subduction zone sites that also have thick, hot sediment and rock, especially those areas where the hazard potential is unknown.

The Cascadia Subduction Zone is one of the most widely studied sites in the world and experts say it may have experienced as many as two dozen major earthquakes over the past 10,000 years.

The sediment at the Cascadia deformation front is between 2.5 and 4.0 kilometers thick, which is somewhat less than the 4-5 kilometer thickness of the Sumatra region. However, because the subducting plate at Cascadia is younger when the plate arrives at the subduction zone, the estimated temperatures at the fault surface are about the same in both regions.

Torres is a professor in Oregon State University’s College of Earth, Ocean, and Atmospheric Sciences.

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Marta Torres, 541-737-2902, mtorres@coas.oregonstate.edu

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Sediment cores

Sediment cores

New study documents aftermath of a supereruption, and expands size of Toba magma system

CORVALLIS, Ore. – The rare but spectacular eruptions of supervolcanoes can cause massive destruction and affect climate patterns on a global scale for decades – and a new study has found that these sites also may experience ongoing, albeit smaller eruptions for tens of thousands of years after.

In fact, Oregon State University researchers were able to link recent eruptions at Mt. Sinabung in northern Sumatra to the last eruption on Earth of a supervolcano 74,000 years ago at the Toba Caldera some 25 miles away.

The findings are being reported this week in the journal Nature Communications.

“The recovery from a supervolcanic eruption is a long process, as the volcano and the magmatic system try to re-establish equilibrium – like a body of water that has been disrupted by a rock being dropped into it,” said Adonara Mucek, an Oregon State doctoral candidate and lead author on the study.

“At Toba, it appears that the eruptions continued for at least 15,000 to 20,000 years after the supereruption and the structural adjustment continued at least until a few centuries ago – and probably is continuing today. It is the magmatic equivalent to aftershocks following an earthquake.”

This is the first time that scientists have been able to pinpoint what happens following the eruption of a supervolcano. To qualify as a supervolcano, the eruption must reach at least magnitude 8 on the Volcano Explosivity Index, which means the measured deposits for that eruption are greater than 1,000 cubic kilometers, or 240 cubic miles.

When Toba erupted, it emitted a volume of magma 28,000 times greater than that of the 1980 eruption of Mount St. Helens in Washington state. It was so massive, it is thought to have created a volcanic winter on Earth lasting years, and possibly triggering a bottleneck in human evolution.

Other well-known supervolcano sites include Yellowstone Park in the United States, Taupo Caldera in New Zealand, and Campi Flegrei in Italy.

“Supervolcanoes have lifetimes of millions of years during which there can be several supereruptions,” said Shanaka “Shan” de Silva, an Oregon State University volcanologist and co-author on the study. “Between those eruptions, they don’t die. Scientists have long suspected that eruptions continue after the initial eruption, but this is the first time we’ve been able to put accurate ages with those eruptions.”

Previous argon dating studies had provided rough ages of eruptions at Toba, but those eruption dates had too much range of error, the researchers say. In their study, the OSU researchers and their colleagues from Australia, Germany, the United States and Indonesia were able to decipher the most recent volcanic history of Toba by measuring the amount of helium remaining in zircon crystals in erupted pumice and lava.

The helium remaining in the crystals is a remnant of the decaying process of uranium, which has a well-understood radioactive decay path and half-life.

“Toba is at least 1.3 million years old, its supereruption took place about 74,000 years ago, and it had at least six definitive eruptions after that – and probably several more,” Mucek said. “The last eruption we have detected occurred about 56,000 years ago, but there are other eruptions that remain to be studied.”

The researchers also managed to estimate the history of structural adjustment at Toba using carbon-14 dating of lake sediment that has been uplifted up to 600 meters above the lake in which they formed. These data show that structural adjustment continued from at least 30,000 years ago until 2,000 years ago – and may be continuing today.

The study also found that the magma in Toba’s system has an identical chemical fingerprint and zircon crystallization history to Mt. Sinabung, which is currently erupting and is distinct from other volcanoes in Sumatra. This suggests that the Toba system may be larger and more widespread than previously thought, de Silva noted.

“Our data suggest that the recent and ongoing eruptions of Mt. Sinabung are part of the Toba system’s recovery process from the supereruption,” he said.

The discovery of the connection does not suggest that the Toba Caldera is in danger of erupting on a catastrophic scale any time soon, the researchers emphasized. “This is probably ‘business as usual’ for a recovering supervolcano,” de Silva said. It does emphasize the importance of having more sophisticated and frequent monitoring of the site to measure the uplift of the ground and image the magma system, the researchers note.

“The hazards from a supervolcano don’t stop after the initial eruption,” de Silva said. “They change to more local and regional hazards from eruptions, earthquakes, landslides and tsunamis that may continue regularly for several tens of thousands of years.

“Toba remains alive and active today.”

As large as the Toba eruption was, the reservoir of magma below the caldera is much, much greater, the researchers say. Studies at other calderas around Earth, such as Yellowstone, have estimated that there is between 10 and 50 times as much magma than is erupted during a supereruption.

Mucek and de Silva are affiliated with OSU’s College of Earth, Ocean, and Atmospheric Sciences. The study was supported by the National Science Foundation. A video of them explaining their research is available at: http://bit.ly/2raULAx

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Adonara “Ado” Mucek, 541-908-1437, muceka@geo.oregonstate.edu;

Shanaka “Shan” de Silva, 541-737-1212, desilvas@geo.oregonstate.edu;

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laketoba

Southward view of the northern third of the Lake Toba depression produced by the supereruption 74,000 years ago.

“Narco-deforestation” study links loss of Central American tropical forests to cocaine

CORVALLIS, Ore. – Central American tropical forests are beginning to disappear at an alarming rate, threatening the livelihood of indigenous peoples there and endangering some of the most biologically diverse ecosystems in North America.

The culprit? Cocaine.

The problem is not the cultivation of the coca plant – which is processed into cocaine – that is causing this “narco-deforestation.” It results from people throughout the spectrum of the drug trade purchasing enormous amounts of land to launder their illegal profits, researchers say.

Results of the study, which was funded by the Open Society Foundations and supported by the National Socio-Environmental Synthesis Center, have just been published in the journal Environmental Research Letters.

“Starting in the early 2000s, the United States-led drug enforcement in the Caribbean and Mexico pushed drug traffickers into places that were harder to patrol, like the large, forested areas of central America,” said David Wrathall, an Oregon State University geographer and co-author on the study. “A flood of illegal drug money entered these places and these drug traffickers needed a way that they could spend it.

“It turns out that one of the best ways to launder illegal drug money is to fence off huge parcels of forest, cut down the trees, and build yourself a cattle ranch. It is a major, unrecognized driver of tropical deforestation in Central America.”

Using data from the Global Forest Change program estimating deforestation, the research team identified irregular or abnormal deforestation from 2001-2014 that did not fit previously identified spatial or temporal patterns caused by more typical forms of land settlement or frontier colonization. The team then estimated the degree to which narcotics trafficking contributes to forest loss, using a set of 15 metrics developed from the data to determine the rate, timing and extent of deforestation.

Strongly outlying or anomalous patches and deforestation rates were then compared to data from the Office of National Drug Control Policy – considered the best source for estimating cocaine flow through the Central American corridor, Wrathall pointed out.

“The comparisons helped confirm relationships between deforestation and activities including cattle ranching, illegal logging, and land speculation, which traffickers use to launder drug trafficking profits in remote forest areas of Central America,” Wrathall said.

They estimate that cocaine trafficking may account for up to 30 percent of the total forest loss in Honduras, Guatemala and Nicaragua over the past decade. A total of 30 to 60 percent of the forest losses occurred within nationally and internationally designated protected areas, threatening conservation efforts to maintain forest carbon sinks, ecological services, and rural and indigenous livelihoods.

“Imagine the cloud of carbon dioxide from all of that burning forest,” Wrathall said. “The most explosive change in land use happened in areas where land ownership isn’t clear – in forested, remote areas of Honduras, Guatemala and Nicaragua, where the question of who owns the land is murky.”

“In Panama, the financial system is built to launder cocaine money so they don’t need to cut down trees to build ranches for money laundering. In Honduras, land is the bank.”

Farming and cattle ranching aren’t the only money laundering methods threatening tropical forests, the researchers say. Mining, tourism ventures and industrial agriculture are other ways drug money is funneled into legitimate businesses.

Wrathall said the impact affects both people and ecosystems.

“The indigenous people who have lived sustainably in these environments are being displaced as the stewards of the land,” he said. “These are very important ecological areas with tremendous biodiversity that may be lost.”

The authors says the solutions include de-escalating and demilitarizing the war on drugs; strengthening the position of indigenous peoples and traditional forest communities to be stewards of the remaining forest lands; and developing regional awareness of the issue.

“We are cruising through the last of our wild spaces in Central America,” Wrathall said. “Obviously, ending the illegal drug trade would be the best solution, but that isn’t going to happen. In fact, when drug enforcement efforts are successful, they often push the activity into remote areas that haven’t had issues before, such as remote biodiversity hotspots.”

Wrathall is an assistant professor in Oregon State University’s College of Earth, Ocean, and Atmospheric Sciences. He specializes in the impact of climate change on the distribution of the human population and other factors that affect human migration.

“The surge of violence in Central America that has accompanied drug trafficking is recognized as a major driver of migration in the region.”

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David Wrathall, 541-737-8051, david.wrathall@coas.oregonstate.edu

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Central American forests are giving way to pasture land for cattle ranches.

New book: Rivers are like the stock market, with boom and bust cycles

CORVALLIS, Ore. – Rivers have long captured the imagination of poets, essayists and other writers, who have used them to tell iconic stories like “Huckleberry Finn,” “The Heart of Darkness,” and “Wind and the Willows.”

Oregon State University geophysicist and author Sean Fleming explores rivers from different angles – where they come from, why they may flood one year and dry up the next, and how almost every aspect of our lives revolves around water.

In his new book “Where the River Flows,” published by the Princeton University Press, Fleming explains that mathematics and physics give us a fresh way to look at rivers. Not to worry, though – it is a book aimed at the lay public and presented in a unique style. He asks questions such as “how do rivers remember?” and “how do clouds talk to fish?” as a way to introduce new topics.

“Ultimately, almost everything revolves around water, from the food we eat and the beer we drink, to hydroelectric power and recreation,” Fleming said. “Rivers are essential to civilization and even life itself, but people rarely delve into what makes them work. And in an interesting way, mathematical ideas underlie the science of rivers and underscore the importance of interconnectedness.”

Fleming uses debris flows as an example. This flood and landslide hybrid, which poses threats around the world, can be explained using a computer simulation called “cellular automata,” which originally was created to explore artificial life.

“It also reveals something about the origins of fractal patterns, which occur in everything from tree branches, to galaxies to the stock market,” Fleming said. “Recognizing that ideas from one field can be so powerful in another is important for pushing science forward.”

In his book, Fleming also points out some oddities about rivers across the world. For example, most rivers have seasonal “heart-beats,” he pointed out, with one peak per year – like the Columbia River’s springtime snowmelt freshet. Across the globe, however, Africa’s Congo River is so big and covers so much territory on either side of the equator that it has two peaks and two troughs because when it is summer in one part of the river it is winter in the other.

The Colorado River provides another oddity. In the upper Colorado, the water flow is impressive, attracting white water rafters for its massive rapids and thrills. But the river doesn’t even end up flowing into the Pacific Ocean any longer because of the demand of people living along its path. That is well-documented. The backdrop to the water usage, however, is not as widely known, Fleming noted.

“The allocations for water from the Colorado River were made in the early 1900s,” he said. “They were based on the observed weather and stream flow at the time, which were expected to remain roughly the same. But little did they know that it turned out to be one of the wettest periods in the basin’s history.

“So the allotments then – and today – were made on the assumption that the river’s flow would be much greater than it actually is.”

Fleming also explores issues of water security and the increasing demand worldwide for fresh water.

“That demand is expected to increase 55 percent by the year 2050, so we may be looking at increased opportunities for cooperation, but also conflict,” he said. “Some people have even predicted water wars. To better manage the resource, we need to make a quantum leap forward in understanding how rivers work and that means looking at them from all angles.”

“Where the River Flows: Scientific Reflections on Earth’s Waterways” is available through the Princeton University Press at: http://press.princeton.edu/titles/10978.html and at Amazon at: http://amzn.to/2r3eOR4

Fleming is a courtesy faculty member in Oregon State’s College of Earth, Ocean, and Atmospheric Sciences.

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Sean Fleming, fleminse@oregonstate.edu

Magnesium within plankton provides tool for taking the temperatures of past oceans

CORVALLIS, Ore. – Scientists cannot travel into the past to take the Earth’s temperature so they use proxies to discern past climates, and one of the most common methods for obtaining such data is derived from the remains of tiny marine organisms called foraminifera found in oceanic sediment cores.

These “forams,” as they are called, are sand-grained-sized marine protists that make shells composed of calcite. When they grow, they incorporate magnesium from seawater into their shells. When ocean temperatures are warmer, forams incorporate more magnesium; less when the temperatures are cooler. As a result, scientists can tell from the amount of magnesium what the temperature of the seawater was thousands, even millions of years ago. These proxies are important tools for understanding past climate.

However, studies of live forams reveal that shell magnesium can vary, even when seawater temperature is constant. A new study published this week in the journal Nature Communications affirms that magnesium variability is linked to the day/night (light/dark) cycle in simple, single-celled forams and extends the findings to more complex multi-chambered foraminifera.

To understand how forams develop and what causes magnesium variability, the team of scientists from Oregon State, University of California, Davis, University of Washington and Pacific Northwest National Laboratory grew the multi-chambered species, Neogloboquadrina dutertrei, in a laboratory under highly controlled conditions. They used high-resolution imaging techniques to “map” the composition of these lab-grown specimens.

“We found that high-magnesium is precipitated at night, and low-magnesium is added to the shells during the day, similar to the growth patterns of the single-chambered species,” said Jennifer S. Fehrenbacher, an ocean biogeochemist and paleoceanographer at Oregon State University and lead author on the study. “This confirms that magnesium variability is driven by the same mechanism in two species with two different ecological niches. We can now say with some level of confidence that magnesium-banding is intrinsically linked to shell formation processes as opposed to other environmental factors.

“The variability in magnesium content of the shells doesn’t change the utility of forams as a proxy for temperature. Rather, our results give us new insights into how these organisms build their shells and lends confidence to their utility as tools for reconstructing temperatures.”

Other co-authors on this study are Ann Russell, Catherine Davis, and Howard Spero at the University of California, Davis; Alex Gagnon at the University of Washington, Zihua Zhu and John Cliff at the Pacific Northwest National Laboratory, and Pamela Martin.

The study was funded by the National Science Foundation and the Department of Energy. Fehrenbacher is an assistant professor in Oregon State’s College of Earth, Ocean, and Atmospheric Sciences.

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 Jennifer Fehrenbacher, 541-737-6285, fehrenje@coas.oregonstate.edu

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N. dutertrei

N. dutertrei grown in a laboratory

Oregon State part of new NSF research program in the Arctic

CORVALLIS, Ore. – Oregon State University and five other universities this week received an award to initiate a new Long-Term Ecological Research (LTER) project in the Arctic that will explore how relationships between the land and water affect coastal ecosystems along the northern Alaskan coast.

The project has been funded by a five-year, $5.6 million grant from the National Science Foundation and will join 25 existing and two recently awarded coastal LTER sites that form a network of terrestrial and aquatic biomes worldwide.

Two of the new coastal sites, the Northern Gulf of Alaska and the Northeastern U.S. Shelf, are in very productive regions for fisheries. The third site, The Beaufort Sea Lagoons, is the first marine ecosystem LTER in the Arctic Ocean. The project, “Beaufort Sea Lagoons: An Arctic Coastal Ecosystem in Transition,” is supported by NSF’s Office of Polar Programs.

 “It is a very rich, very important ecosystem and we don’t have a good understanding of how it works,” said Yvette Spitz, one of two OSU oceanographers who are principal investigators with the project. “There are chemicals, nutrients and other organic materials that are transported from the land to the ocean, passing through lagoons along the way.”

“One of the goals of the project is to understand how the transport of these materials is affected by changing precipitation, sea ice and melting permafrost – and what effect that has on biological productivity. These changes are presently occurring and are the most rapid in the Arctic”

Scientists at the University of Texas at Austin are leading the project, in collaboration with researchers at Oregon State, University of Alaska Fairbanks, University of Texas El Paso, University of Massachusetts at Amherst and University of Toronto Mississauga.

Also participating will be young scientists from the native Iñupiat communities of Utqiagvik (formerly Barrow) and Kaktovik, and the U.S. Fish and Wildlife Service, which manages the Arctic National Wildlife Refuge.

“An important aspect of this LTER is the collaboration between scientists and the Iñupiat residents of the Beaufort Sea coast, which will greatly deepen our comprehensive understanding of these ecosystems,” said William Ambrose, director of the Arctic Observing Network in the NSF Office of Polar Programs.

The research will be based in Kaktovik, Utqiagvik, and Prudhoe Bay, Alaska. It will focus on a series of large, shallow (5-7 meters deep) lagoons that play a role in the transition of materials from land to sea.

Byron Crump, the other OSU oceanographer who is a principal investigator on the project, will focus on the smallest but most abundant organisms in the ecosystem – phytoplankton, bacteria, and other microbes.

“The old school of thinking was that bacteria were important in warmer ecosystems but not so much in colder regions like the Arctic,” Crump said. “We’re finding that isn’t true at all. Bacteria and other tiny organisms play critical roles in maintaining the food web that supports everything from krill to whales as well as important fisheries.”

Crump will look at the growth rates and genomic diversity of microbes, while Spitz will develop computer models that will evaluate how microbes, plankton and other small organisms influence the ecosystem and how they will be affected in the future under different scenarios of warming, increased precipitation and changes in groundwater.

Spitz and Crump are faculty members in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

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Yvette Spitz, 541-737-3227, yspitz@coas.oregonstate.edu;

Byron Crump, 541-737-4369, bcrump@coas.oregonstate.edu

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Photo of Beaufort lagoons (left): https://flic.kr/p/Sp3DZ5

 

 

 

Coastal erosion

Coastal erosion is one of the processes researchers will study.

OSU to expand sediment core collection to one of largest in the world

CORVALLIS, Ore. – One of the nation’s most important repositories of oceanic sediment cores, located at Oregon State University, will more than double in size later this year when the university assumes stewardship of a collection of sediment cores taken from the Southern Ocean around Antarctica.

OSU has received a pair of grants from the National Science Foundation to assume the curatorial stewardship of the Antarctic and Southern Ocean National Collection of Rock and Sediment Cores, housed at Florida State University since the mid-1960s. Oregon State will house the expanded collection in a sophisticated new facility located just off-campus.

NSF manages the U.S. Antarctic Program, whose logistical support and awards to researchers allowed many of the cores to be obtained.

The OSU Marine and Geology Repository will be available to scientists around the world to study the sediment cores, which provide evidence of the Earth’s climate over the past millions of years, oceanic conditions, the history of the magnetic field, plate tectonics, seismic and volcanic events, ice ages and interglacial periods, and even the origin of life.

“These cores are time capsules, allowing scientists today to compare the conditions on the Earth we live in with the way it was eons ago,” said Thom Wilch, Earth Sciences program manager at NSF. “This collection of cores and samples is an incredible resources that has yielded many important scientific findings about the past. Preservation and curation by OSU ensures that the cores are available for future research by the national and international scientific communities.”

Oregon State has operated a sediment core lab since the 1970s, but its origins were rather modest, according to Joseph Stoner, a geologist in the College of Earth, Ocean, and Atmospheric Sciences and co-director of the OSU Marine and Geology Repository. Lacking a storage facility, the first cores were kept in a cooler at a Chinese restaurant in Corvallis.

From those humble beginnings, the repository has grown into a treasure trove for scientists, storing thousands of cores – mostly from the Pacific Ocean, with a few from the Arctic, Bering Sea, and many terrestrial lakes. The collection also includes dry terrestrial cores and dredged rocks from submarine volcanoes and the ocean floor.

“The expanded collection will include some 35 kilometers, or about 22 miles, of sediment cores, more than doubling the size of our current repository at Oregon State,” Stoner said. “OSU already shares on average 5,000 subsamples of the cores with scientists each year – a number that will more than double with the expansion.”

When completed over the next two years, the expanded repository will give Oregon State the premier collection of sediment cores from the Pacific and Southern oceans. It is difficult to put a dollar value on the cores, OSU researchers say, though their worth can be calculated in a different way.

“If we had to replace the cores in our current OSU repository, it would cost roughly a half billion dollars just in ship time to go collect them,” Stoner said. “That doesn’t include the cost of the people involved. To replace the Antarctic collection would easily cost more than $1 billion, since the Southern Ocean is so remote, travel is difficult, and you can only work two or three months out of the year.”

The real worth, though, is the cores’ scientific value, noted Anthony Koppers, co-director of the OSU repository and also a faculty member in the College of Earth, Ocean, and Atmospheric Sciences. The OSU collection includes cores that have sediments as old as 50 million years, and from as deep as a kilometer below the Earth’s surface.

The new Antarctic collection has the most complete set of cores from the Southern Ocean in the world and those cores provide an important look into the Earth’s climate history over the last few million years. The Southern Ocean collection also includes numerous cores gathered under the NSF-funded international Antarctic DRILLing Project (ANDRILL) program and provides clues to the history of the Antarctic Ice Sheet over the past 17 million years.

“This will bring a lot of researchers from around the world to Oregon State,” Koppers said. “The Antarctic research community is very active, very enthusiastic, and very diverse. With our new facility, we will have the capacity to work with researchers in numerous disciplines studying a variety of scientific questions.”

Oregon State will spend the next several months preparing the new facility, which will be unlike almost every other repository in the world. It will have a refrigerated industrial storage space of 18,000 square feet, the researchers note, providing plenty of room for the collection to grow over the next five decades.

The size of the facility likely will lead to other collections moving to Oregon State, Koppers predicted.

“Most core repositories are starving for space,” he said. “We anticipate hearing from them as word about the transfer and our new facility gets out.”

The new repository facility will occupy much of the former Nypro Building in Corvallis. In addition to the enormous refrigerated storage area, which has 28-foot-high ceilings for both cold and dry storage, it will include:

  • Up to 11 laboratory areas, including facilities for core splitters, imagery, microscopy, rock analysis, sediment analysis CT scanning and other scanning techniques;
  • Freezer storage for frozen ice cores from Greenland and Antarctica;
  • A laboratory where researchers can work on eight different cores at once while using digital imaging and data from the individual cores displayed on large-screen computer monitors;
  • A seminar room for 35 people, where cores can be brought in for classes and presentations;
  • Office space for resident scientists, staff, and visiting scientists.

Florida State University made the decision in 2015 not to compete for renewal as its Earth, Ocean, and Atmospheric Science program was moving in a different academic direction. Koppers and Stoner submitted a bid for Oregon State to acquire the collection and were awarded two grants from NSF to transfer the Antarctic collection and to provide stewardship for it.

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Joseph Stoner, 541-737-9002, jstoner@coas.oregonstate.edu;

Anthony Koppers, 541-737-5425, akoppers@coas.oregonstate.edu

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Scientists: Warming temperatures could trigger starvation, extinctions in deep oceans by 2100

CORVALLIS, Ore. – Researchers from 20 of the world’s leading oceanographic research centers today warned that the world’s largest habitat – the deep ocean floor – may face starvation and sweeping ecological change by the year 2100.

Warming ocean temperatures, increased acidification and the spread of low-oxygen zones will drastically alter the biodiversity of the deep ocean floor from 200 to 6,000 meters below the surface. The impact of these ecosystems to society is just becoming appreciated, yet these environments and their role in the functioning of the planet may be altered by these sweeping impacts. 

Results of the study, which was supported by the Foundation Total and other organizations, were published this week in the journal Elementa.

“Biodiversity in many of these areas is defined by the meager amount of food reaching the seafloor and over the next 80-plus years – in certain parts of the world – that amount of food will be cut in half,” said Andrew Thurber, an Oregon State University marine ecologist and co-author on the study. “We likely will see a shift in dominance to smaller organisms. Some species will thrive, some will migrate to other areas, and many will die. 

“Parts of the world will likely have more jellyfish and squid, for example, and fewer fish and cold water corals.”

The study used the projections from 31 earth system models developed for the Intergovernmental Panel on Climate Change to predict how the temperature, amount of oxygen, acidity (pH) and food supply to the deep-sea floor will change by the year 2100. The authors found these models predict that deep ocean temperatures in the “abyssal” seafloor (3,000 to 6,000 meters deep) will increase as much as 0.5 to 1.0 degrees (Celsius) in the North Atlantic, Southern and Arctic oceans by 2100 compared to what they are now. 

Temperatures in the “bathyal” depths (200 to 3,000 meters deep) will increase even more – parts of this deep-sea floor are predicted to see an increase of nearly 4 degrees (C) in the Pacific, Atlantic and Arctic oceans.

“While four degrees doesn’t seem like much on land, that is a massive temperature change in these environments,” Thurber said. “It is the equivalent of having summer for the first time in thousands to millions of years.” 

The over-arching lack of food will be exacerbated by warming temperatures, Thurber pointed out.

“The increase in temperature will increase the metabolism of organisms that live at the ocean floor, meaning they will require more food at a time when less is available.” 

Most of the deep sea already experiences a severe lack of food, but it is about to become a famine, according to Andrew Sweetman, a researcher at Heriot-Watt University in Edinburgh and lead author on the study.

“Abyssal ocean environments, which are over 3,000 meters deep, are some of the most food-deprived regions on the planet,” Sweetman said. “These habitats currently rely on less carbon per meter-squared each year than is present in a single sugar cube. Large areas of the abyss will have this tiny amount of food halved and for a habitat that covers half the Earth, the impacts of this will be enormous.” 

The impacts on the deep ocean are unlikely to remain there, the researchers say. Warming ocean temperatures are expected to increase stratification in some areas yet increase upwelling in others. This can change the amount of nutrients and oxygen in the water that is brought back to the surface from the deep sea. This low-oxygen water can affect coastal communities, including commercial fishing industries, which harvest groundfish from the deep sea globally and especially in areas like the Pacific Coast of North America, Thurber said.

“A decade ago, we even saw low-oxygen water come shallow enough to kill vast numbers of Dungeness crabs,” Thurber pointed out. “The die-off was massive.” 

Areas most likely to be affected by the decline in food are the North and South Pacific, North and South Atlantic, and North and South Indian oceans.

“The North Atlantic in particular will be affected by warmer temperatures, acidification, a lack of food and lower oxygen,” Thurber said. “Water in the region is soaking up the carbon from the atmosphere and then sending it on its path around the globe, so it likely will be the first to feel the brunt of the changes.” 

Thurber, who is a faculty member in Oregon State’s College of Earth, Ocean, and Atmospheric Sciences and the OSU College of Science, has previously published on the “services” or benefits provided by the deep ocean environments. The deep sea is important to many of the processes affecting the Earth’s climate, including acting as a “sink” for greenhouse gases and helping to offset growing amounts of carbon dioxide emitted into the atmosphere.

These habitats are not only threatened by warm temperatures and increasing carbon dioxide; they increasingly are being used by fishing and explored by mining industries for extraction of mineral resources. 

“If we look back in Earth’s history, we can see that small changes to the deep ocean caused massive shifts in biodiversity,” Thurber said. “These shifts were driven by those same impacts that our model predict are coming in the near future. We think of the deep ocean as incredibly stable and too vast to impact, but it doesn’t take much of a deviation to create a radically altered environment.

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Andrew Thurber, 541-737-4500, athurber@coas.oregonstate.edu; Andrew Sweetman, +44 (0) 131 451 3993, a.sweetman@hw.ac.uk

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Sea pig (Image Courtesy of Ocean Networks Canada)

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Methane seep (Image by Andrew Thurber, OSU)

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2015-16 weather event took toll on California beaches; not so much for Oregon, Washington

CORVALLIS, Ore. – The 2015-16 El Niño was one of the strongest climate events in recent history with extraordinary winter wave energy, a new study shows, though its impact on beaches was greater in California than in Oregon and Washington.

The reason, researchers say, is that the Pacific Northwest had experienced comparatively mild wave conditions in the years prior to the onset of the El Niño, while California was experiencing a severe drought and “sediment starvation.”

Results of the study are being published this week in Nature Communications.

“Rivers still supply the primary source of sand to California beaches, despite long-term reductions due to extensive dam construction,” said Patrick Barnard, a geologist with the U.S. Geological Survey and lead author on the study. “But as California was in the midst of a major drought, the resulting lower river flows equated to even less sand being carried to the coast to help sustain beaches.

“Therefore, many of the beaches in California were in a depleted state prior to the El Niño winters, and thereby were subjected to extreme and unprecedented landward erosion due to the highly energetic winter storm season of 2015-16.”

The West Coast, on average, experienced a “shoreline retreat” – or degree of beach erosion – that was 76 percent above normal and 27 percent higher than any other winter on record, eclipsing the El Niño events of 2009-10 and 1997-98. Coastal erosion was greatest in California, where 11 of the 18 beaches surveyed experienced historical levels of erosion.

Peter Ruggiero, an Oregon State University coastal hazards expert and co-author on the study, said Oregon and Washington were not affected to the same extent.

“You would have thought that there would be massive damage associated with erosion in Oregon and Washington with the strength of this El Niño,” said Ruggiero, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “But the previous three years had mild winters and therefore the sand buildup was much higher than in California. It helped the Northwest offset the potential erosion from the El Niño.”

Oregon and Washington also have broader beaches than in California, Ruggiero pointed out, which also eases the erosion of sand dunes and impacts to development.

The 2015-16 El Niño, in some ways, was stronger than the 1982-83 event, which caused an estimated $11.5 billion in damages, the researchers say in the study. Only a portion of the damage was directly related to coastal erosion, with damage to houses and roads, they note. Most of the impact was from related storms, flooding and other damage that occurred inland.

The Nature Communications study is important, the authors say, because it is one of the first attempts to document the oceanographic “forcing” directly related to beach impacts created by El Niño. The study documents the amount of power created by winter storm waves, using height and “period” – or the length of time between waves. It is the level of forcing, along with relative beach health, that dictates the amount of erosion that occurs and the associated impacts from that erosion.

“During an El Niño, the nearshore experiences higher water levels because of the storms and the fact that the water is warmer and expands,” Ruggiero said. “In Oregon, the water was about 15-17 centimeters (roughly 6-7 inches) higher than average, which led to higher storm tides.”

Although Northwest beaches were buffered from catastrophic damage, Ruggiero said, they did experience significant retreat. And it may take a while for the beaches to rebuild.

“We’re not completely recovered yet, and it may take years for some beaches to build back up,” he said. “After the 1997-98 El Niño, it took some beaches a decade to recover.”

Ruggiero, his students and colleagues have been monitoring Northwest beaches since 1997, and in 2015, they received a National Science Foundation rapid response grant to study the impact of El Niño on beaches. Ruggiero also receives support from the Northwest Association of Networked Ocean Observing Systems (NANOOS) and the U.S. Army Corps of Engineers for additional monitoring.

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Peter Ruggiero, 541-737-1239, pruggier@coas.oregonstate.edu; Patrick Barnard, 831-460-7556, pbarnard@usgs.gov

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South Beach, Oregon
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(Left: Crescent Beach in Callifornia. Photos by Nick Cohn, Oregon State University. https://flic.kr/p/RwDLsb)