This 3-D view of the magmatic system beneath the Snake River Plain and Yellowstone National Park is inferred from magnetotelluric data. At each point on this surface, the magnetic field has a constant or lower value. The actual locations at which data were collected are shown by the dots on top. Yellowstone is indicated with an open circle. Note the conductive pathway to the Yellowstone caldera from beneath the eastern Snake River Plain. (Figure courtesy of Anna Kelbert. Source: Kelbert A., Egbert G.D., deGroot-Hedlin C. 2012. “Crust and upper mantle electrical conductivity beneath the Yellowstone Hotspot Track” Geology, v. 40, p. 447-450, doi:10.1130/G32655.1)

A geological mystery lies beneath the majestic beauty of Yellowstone National Park. Once thought solved, the enigma continues to unfold through the lens of a young science known as magnetotellurics.

As accepted theory goes, over the past 16 million years a rising plume of magma in the Earth’s mantle produced massive amounts of lava and ash in a path stretching from the Snake River Plain to its current caldera — a volcanic crater in Wyoming, the Yellowstone “supervolcano.” It is widely believed that the Yellowstone caldera currently sits on top of that hotspot, a vertical “blowtorch” in the mantle beneath the Earth’s crust. The North American tectonic plate slowly creeps over the plume of magma, no faster than the rate at which fingernails grow. The plume sometimes oozes and other times violently erupts lava across an area the size of Rhode Island. Adam Schultz, a geophysics professor in Oregon State University’s College of Earth, Ocean, and Atmospheric Sciences, describes this mantle hotspot idea as “almost a cartoon view that Earth scientists have of why you get features like Yellowstone.”

Magnetotellurics (MT), the study of the Earth’s electric and magnetic fields, may turn this cartoon view on its head. The use of magnetotelluric surveys has exploded in the last decade thanks to progress in computing technology and geophysical instrumentation. Schultz’s colleagues at Oregon State — Anna Kelbert and Gary Egbert  — have used magnetotellurics to reveal that large volumes of partially molten rock and potentially superheated water (hydrothermal systems) snake west underneath the crust and into the uppermost mantle west of Yellowstone. This molten trail continues westward along much of the Snake River Plain in Idaho and into Oregon. These findings complicate the expectation that a nearly vertical magma plume lies directly under the present day Yellowstone supervolcano, which was what is anticipated from a hotspot. Magnetotellurics has opened doors to stunning breakthroughs and fascinating discoveries, providing new perspectives that were once invisible to science.

Research assistant Tristan Peery, left, and Adam Schultz are analyzing changes in subsurface rock as part of a geothermal energy study by AltaRock, Inc. (Photo: Dennis Wolverton, courtesy of the Oregon Stater magazine)

From Magnetics to Melted Rock

With magnetotellurics, scientists measure variations in the direction and intensity of the planet’s natural magnetic and electric fields over time. They use these measurements to understand the properties of the rock, one of the most important being electrical conductivity. Generally, greater electrical conductivity can suggest the presence of extensively interconnected bodies of fluid within the rock. West of Yellowstone, magnetotellurics reveal a relatively shallow, hot, highly conductive region under the Snake River Plain.

Schultz compares magnetotelluric surveys to MRIs commonly used in medical diagnostics. In fact the underlying principles are similar. “If you go to a radiology department and they do a CT scan of your head, for example, they see some weird thing, and they’re not quite sure what it is. You have an MRI and go, ‘ah! that’s a brain tumor,’” says Schultz.

In the same way, MT can be thought of as a very large MRI. And just as doctors put together multiple types of scans to see inside our bodies, geophysicists combine seismology, magnetotellurics and measurements of the on-going deformation of the Earth’s surface through GPS and satellite radar data to see what’s underground. Schultz’s focus on the Yellowstone caldera is part of a larger project, the magnetotelluric component (also known as EMScope) of the National Science Foundation’s EarthScope Program.

Topography of Yellowstone-Snake River Plan study area (see inset map for location within the United States), with physiographic provinces outlined in red. USArray magnetotelluric (MT) site locations used for this study are marked with blue dots; 32 sites from the earlier Snake River Plain profiles are denoted by green dots. Smaller gray dots indicate heat flow from an earlier study by Pollack et al. (1991), ranging from 0 (white) to >300 mW/m2 (black) (Figure courtesy of Amna Kelbert; Source: Kelbert A., Egbert G.D., deGroot-Hedlin C. 2012. “Crust and upper mantle electrical conductivity beneath the Yellowstone Hotspot Track” Geology, v. 40, p. 447-450, doi:10.1130/G32655.1)

Schultz, a former program director for the NSF, heads EMScope. In the quest to understand more about the history of the North American continent, EarthScope makes seismic, GPS and MT surveys of the United States and part of Canada. EMScope provides the geomagnetic facet of the survey, producing 3-D images of Earth’s electrical conductivity variations beneath the continent.

Sweeping west to east, scientists are deploying portable arrays of magnetometers and electric field sensors in plastic boxes buried a foot or two in the ground. These small devices silently collect data over a period of one to three weeks, depending on the level of solar storm activity, which provides the source of their signal. Remarkably, the stream of charged particles emitted from the Sun’s atmosphere, the “Solar Wind,” is what makes this all happen. Some of those particles are captured by the Earth’s magnetic field and form gigantic electric currents that flow above the atmosphere, the most famous of which are the aurora (the Northern and Southern Lights). These currents cause other electric currents to flow inside the Earth’s crust and mantle, generating a signal that is detectable by MT devices.

Ancient Rift Revealed

Schultz first encountered geophysics at Brown University in 1979 when MT systems and computers were the size of travel trailers. Instruments today are small, rugged and more mobile. Teams of scientists are currently creating 3D images of the electrical conductivity beneath the comparatively flat landscape of the Midwest. Early results already reveal a billion-year-old ancient rift down the center of the continent, a feature hidden by vast seas of crops and flattened by millions of years of erosion. Magnetotellurics provides a view that goes below the region’s apparent horizon-to-horizon uniformity.

In Oregon, Schultz also leads a magnetotelluric study contributing to the potential geothermal development of Newberry Volcano just south of Bend. Nearly 20 times larger than Mount St. Helens, Newberry is Oregon’s largest volcano. Its flanks slope so gently that it’s hardly visible from any roadside viewpoint. In fact, the city of Bend sits close to the northern flank. The volcano isn’t dead, however. Massive amounts of heat lie just beneath the surface, a potentially large source of alternative energy waiting to be utilized.

The U.S. Department of Energy’s National Energy Technology Lab (NETL) has contracted with Oregon State to monitor and assist in the development of a geothermal system on the caldera’s western rim. AltaRock, a geothermal energy company, aims to demonstrate that sufficient heat can be harnessed from deep beneath the surface. It might be possible to generate electricity at commercially competitive levels. To do so, technicians begin by injecting cold fluids at high pressure into the cracks and crevices in the blistering but otherwise dry basalt underground. Ultimately, those heated fluids could then be extracted to create steam and drive electric turbines to generate power.

Unfortunately, water changes the rock to clay, creating a slimy obstacle that would block the cracks and shut off the water flow back to the surface. However, the fluids also change conductivity, and this property allows geophysicists like Schultz to make 3-D surveys that help identify clogs in the plumbing and keep the water flowing and creating steam.

There’s even a future for magnetotellurics in ocean-wave energy. Turbine buoys used in wave-energy projects generate electromagnetic fields. Since some marine species may be sensitive to electric and magnetic fields, the turbines could potentially disrupt marine ecosystems. To ensure the safety of these fragile areas, Schultz and his team are developing new sensors to gather electromagnetic, seismic and other data. The latest sensor, affectionately called Beaver 1 by the National Geoelectromagnetic Facility, Schultz’s lab, is destined for the ocean floor beneath wave turbines off the Oregon coast.

Continental Collision

Back at Yellowstone, data from MT surveys offer evidence of a more complex explanation for the heat beneath the world’s first national park. While the EMScope sensors have moved on to other areas, early results show the melted remains beneath and to the west of the giant volcano. They whisper of a subducted past. Over 200 million years ago, the Farallon plate, the ancient piece of crust between the North American and Pacific tectonic plates, began to dive beneath young North America. Geologists have known for some time that rather than angling steeply toward the mantle, the Farallon hugged the base of the continent all the way to the current Rocky Mountains. About 16 million years ago, interactions between the diving plate and a mantle plume began forming the volcanic features of the Snake River Plain and Yellowstone before eventually descending to be recycled. All that’s left of the Farallon, mere slivers of its past size, grinds today beneath the coast of North and Central America. Off the Pacific Northwest coast, those remains are called the Juan de Fuca plate.

Geoscientists are still debating what the MT data mean for the evolution of the continent and for specific areas such as Yellowstone. Kelbert, Egbert and Schultz plan to refine their understanding with more magnetotelluric studies of the crust in higher resolution. EMScope is only a first step in 3-D geomagnetic surveys, and the discovery beneath Yellowstone is only a chapter of a complex history. This young science will undoubtedly illuminate more untold stories that lie beneath our feet. Geophysicists will have their hands full for years to come.

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Amanda Enbysk is a senior in the College of Earth, Ocean, and Atmospheric Sciences.

The article contains an account of work sponsored by the Department of Energy and the National Science Foundation, both agencies of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed therein do not necessarily state or reflect those of the United States Government or any agency thereof.

Julia Rosen explains how to extract ancient air from ice samples in OSU’s Ice Core Laboratory (Photo: Jeff Basinger)

A shard of ice sits on the black surface of the lab desk, buoyed in a growing puddle. Three small heads hover above in a tight huddle. “It’s cold,” notes one of the kids. Somehow, this obvious observation always catches me off guard, as if I’ve forgotten the most fundamental quality of water’s solid phase. “That’s true,” I reply, “it’s also 10,000 years old.”

“Wow!” the students chorus, and their eyes widen as they look again with renewed awe at this innocuous specimen that could have come from an ice-cube tray in their freezer. Whether I am visiting loquacious third-graders or shyly curious middle-schoolers, I am always touched by the unjaded willingness of youth to imagine and attempt to grasp the unseen. It’s the reason every scientist falls in love with science.

I analyze ice cores in the Oregon State University Ice Core Laboratory and no longer think about their cool touch. I have learned that, like people, the most interesting things about them lie hidden inside. And, like people, it takes time and patience to understand them. When we succeed, these frozen time capsules from Greenland and Antarctica allow us to reconstruct climate far into the past so that by understanding its natural rhythms and quirks, we can predict what kind of future awaits these students.

But let’s start with the obvious: a clear, smooth cylinder of ice glittering with tiny bubbles like a flute of frozen champagne. Stunningly boring to behold, only an occasional band of volcanic ash or the subtle cloudy layers formed during dusty polar winters break its translucent monotony. However, this continuity is actually an ice core’s greatest strength. It provides a complete, unbroken record of past climates, one that is unavailable in almost any other natural archive.

As detectives of Earth’s history, geologists reconstruct stories from snapshots of ancient seas and whispers of long-dead creatures, piecing together a hazy story of our planet’s past. Ice cores are the long-lost diaries of climate. Every day, they recorded the temperature, sniffed the air and noted the snowfall. They sensed changes far from their polar homes — the amount of dust lofted from Asia, the gurgle of tropical volcanoes and much more. From the top to the bottom of a core lie flakes that witnessed every moment of geologic time that elapsed in between.

Thin Air

Physicists, chemists and geologists have spent 60 years learning to translate the primordial language of ice. Early pioneers of ice-core science discovered that they could estimate temperature using the chemistry of rain and snow. As the air warms, precipitation gathers more heavy molecules and fewer light molecules (known as isotopes) of water. The ratio of these isotopes thus provides a record of temperature. These scientists had the transformative idea of using old ice to reconstruct climate by exploiting this valuable relationship.

Each new analytical tool that becomes available to scientists provides another Rosetta Stone for decoding long-lost archives of the ice. Today, we can measure trace amounts of chemical impurities deposited on the ice sheets as dust and aerosols. They tell us how sea ice waxed and waned and which way the wind blew. They reveal the fingerprints of individual volcanic eruptions. While only the pristine inner core provides suitably clean ice for these highly sensitive measurements, the “snow dust” from cutting and cleaning the core does not go to waste. It can be used, for example, to reconstruct concentrations of a rare element, beryllium-10. Produced by cosmic rays high in the atmosphere, the abundance of this element reflects shifts in solar radiation.

Lit by an Arctic midnight sun, this iceberg was spawned by one of Greenland’s fastest moving glaciers near Illulissat. About 400 feet high, it covered an area larger than a city block. (Photo: Julia Rosen)

Of all the stories that ice cores tell, however, the bubbles of air embedded within them actually contain the most impressive secrets. As snow accumulated over thousands of years, slowly hardening into solid ice and forming the massive polar ice sheets, it sealed off little breaths of ancient air between the grains of snow — the very same air we would have inhaled if we had stood on top of the ice sheet 8,000 years ago, or 80,000 or 800,000. From those microscopic samples, we can retrace the evolution of our planet’s atmosphere across almost a million years of Earth history, a period that encompasses nearly all of human existence.

Revelations

In Antarctica, where extreme cold and meager snowfall limit the flow of ice, these cores stretch back across eight glacial cycles. During each, the Earth oscillated between periods of cold climate and expansive ice, including a vast glacial blanket that smothered northern North America, and a time of balmy warmth with ice sheets comparable in size to those on Earth today. Wobbles in the planet’s orbit periodically brought it closer to and farther from the sun’s furnace, setting the rhythm of the climatic metronome.

Across these dramatic changes, carbon dioxide and other greenhouse gases rose and fell with the global temperature as the Earth’s oceans and biosphere adjusted to a changing environment. These gases both responded to climate change and amplified it through their potent ability to trap the Earth’s outgoing energy. But never in the past 800,000 years did these gases reach concentrations even remotely approaching current levels, and never did they rise so quickly, or shoot up at the end of an interglacial period when the receding sun should have lulled the Earth back into an icy slumber.

At the other pole, ice cores in Greenland felt those same changes, although the records of climate before 120,000 years ago crept away through the unstoppable march of glaciers to the sea. Nonetheless, these cores tell us something else completely new. Throughout the last cold period on Earth, which our ancestors waited out in the mild climates of Africa, the Northern Hemisphere experienced a barrage of climate changes so swift and so huge that certain places on Earth warmed by 20 degrees Fahrenheit in a matter of decades. The cause of these dramatic jolts remains a mystery, but their power to radically reorganize the Earth system attests to the inherent volatility of the world in which modern civilization has only recently made a home.

We are slowly beginning to understand the anatomy of global climate and how it changes, its geographic fingerprint and its tempo. Ice cores paint a complex and sometimes surprising picture, one that generations of scientists will spend decades trying to fully understand. We now know the correct greenhouse gas concentrations to feed into our calculations as we simulate past climates in order to validate models for the future.

Ice cores have made one thing abundantly clear: Humans are in uncharted territory. In 800 millennia of records, no entries document a climate like the one we live in today. Even as you read this, we are busy writing the next page of the ice-core diaries.

Illustration by Hank Osuna

Time to Listen

These observations from opposite poles forewarn a perilous future for our planet. We know without question that we’ve entered a period in geologic history for which there is no natural analog, and we know that the Earth’s climate can respond dramatically to perhaps even the smallest nudge.

However, the most terrifying lesson I learned from ice cores did not come from drilling into the past, but from just standing on the surface. At 80 degrees North, well above the Arctic Circle in the empty white wilds of the Greenland ice sheet, I watched a supply plane on skis repeatedly try to lift off. First the crew dumped cargo and then off-loaded all their fuel except what they needed to get home. Finally, on their seventh attempt, they succeeded.

The problem? The snow had warmed to the freezing point, and microscopic drops of water on the surface made the friction between the skis and the ice too great to break. Last summer, 97 percent of the surface of Greenland experienced temperatures above freezing, more than any year in NASA’s 30 years of satellite observations.

The ice cores have told us all they know, and now it’s up to us to listen.

Editor’s note: Julia Rosen is working toward her Ph.D. in the Oregon State University Ice Core Laboratory under the guidance of Ed Brook, professor in the College of Earth, Ocean, and Atmospheric Sciences and a Fellow of the American Association for the Advancement of Science. Support for the lab has come from the National Science Foundation’s Office of Polar Programs.

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For more information:

Analysis of Greenland Ice Cores Adds to Historical Record and May Provide Glimpse into Climate’s Future (Jan. 24, 2013)

Antarctic Ice Core Contains Unrivaled Detail of Past Climate, (Feb. 5, 2013)

Dinoflagellate Ceratium with star-shaped Acantharians in the background (Photo: Angelicque White)

During a Pacific Ocean research cruise, Angel White peers into her microscope. The ship rides gentle swells and sways side to side. In her field of view, organisms the size of dust motes rise and fall through their own watery world. “It can be disorienting and enthralling at the same time. The microbes are dying as I look at them, and it doesn’t always make for the best photos,” she says.

White studies plankton, the microorganisms that power the marine food chain, pump oxygen into the atmosphere and regulate global chemical cycles. In the course of her research, she has recorded an astonishing diversity of living shapes, forms, colors and patterns: spiny Radiolarians, fat copepods, football-shaped ostracods and coiled threads of Trichodesmium that coalesce into filamentous balls. Under fluorescent light, her photos reveal organisms within organisms, glowing constellations that rival images from the best space telescopes.

White’s science is strictly down to Earth. The assistant professor in the College of Earth, Ocean, and Atmospheric Sciences aims to reveal how plankton consume and release nutrients such as nitrogen and phosphorus and how, in turn, these abundant organisms respond to variations in temperature and water chemistry. Her tools run the gamut from high-tech instruments to old-school nets towed behind a ship. In the lab, her camera has become invaluable in her exploration of a world that is largely invisible to the naked eye.

Three isopods clutch one another (Photo: Angelicque White)

“Photography is a wonderful outlet for creativity and discovery,” she adds. “Plankton show an amazing array of different adaptations to their environment. If you concentrate them in a drop of ocean water and look through the microscope, you will see organisms feeding, swimming, gliding, tumbling and floating. There are blues and reds, jaws and antennae — whole alien worlds.”

Call to Artists

In 2012, 35 Oregon artists took up a call from The Arts Center of Corvallis for works based on White’s plankton images. Submissions came from painters, fabric and glass artists, sculptors, potters and an expert in the ancient Japanese art of stencil dyeing. They comprised a show, The Art of Plankton, Form Follows Function.

The range of art gave White a new view of a world that she has explored through her research. “I’ve been fortunate over the years to look through a microscope and be thrilled with the familiar and the mysterious,” she says. “And now to have a whole range of creative people re-envision what I saw the first time is very cool. The natural world can be astonishingly beautiful.

“The general view is that scientists pick it apart and explain it through cold and methodical equations. It is easy to get lost in the details and lose a sense of wonder. This collaboration — merging the perspectives and talents of artists with science — is refreshing. It reminds me what it was like that first time at sea, the first time I realized that, ‘oh no, really, the ocean teems with life, glorious tiny life.’ That sense of discovery is what I felt talking to the artists.”

Drifters 1, Leah Wilson, Eugene

Leviathan, Rakar West, Eugene

Parum Aqua Flora, Sidnee Snell, Corvallis

Emiliana Coccolithophore, Ella Rhoades, Corvallis

Drifters, Sara McCormick, Portland

Blue Button, Sandra Schock-Houtman, Corvallis

Tondos, Jenny Gray, Corvallis

Benthos, Jerri Bartholomew, Corvallis

The Collection, Chi Meredith, Corvallis

Mount Hood's crater is rimmed with unstable cliffs, which can collapse and send an avalanche of rock down the mountain. Timberline Lodge is located on the remnants of one such event. (Photo: Adam Kent)

Mount Hood last erupted more than 200 years ago, but at Crater Rock, not far from the summit, the signs of volcanic activity are unmistakable. Gas vents and hot springs emit sulfur fumes. Vapors rising from deep under the mountain carve snow caves, which can seem like sanctuaries for climbers but often hold deadly concentrations of CO2 and other gases. Rocks fall frequently from the steep unstable cliffs of the partially collapsed crater.

Odds are low that Oregon’s tallest mountain will erupt any time soon, but when it does, scientists have a pretty good idea of what will happen. Driven by the grinding of tectonic plates deep in the planet’s crust, hot magma will infuse cooler lava chambers closer to the surface (an event geologists call “recharge”). Pressure will build. Rocks will begin to crack.

In some volcanoes, not much happens after recharge. The lava chambers may be hotter and ready to burst, but the lid stays on, and the molten rock gradually cools. It takes quite a punch to force a mass the consistency of oatmeal up through miles of tortuous fractures.

Hood, however, is impatient. Within weeks of recharge, lava starts moving and gases start bubbling out through the crater. Melting snow and ice generate debris flows down the mountain’s flanks sweeping away forests and filling rivers with sand and rock. (In the distant past, such events have careened down the Hood River valley and across the Columbia River.) Eventually, lava emerges and snakes down the mountainsides, adding to Hood’s bulk and remaking its classic profile.

That’s been the story for more than a half-million years, says Adam Kent, Oregon State University geologist. When he first arrived in Oregon in 2003, the Australia native learned that while scientists from the U.S. Geological Survey’s Cascade Volcano Observatory knew a lot about hazards posed by eruptions, Hood’s underground plumbing remained largely a mystery.

Since then, Kent has analyzed the remnants of old lava flows to learn how the mountain behaves. He and post-doctoral researcher Alison Koleszar have climbed to the crater, brought samples back to their labs and squeezed clues from rocks. The chemical composition of Hood’s lava flows has remained amazingly uniform over the centuries, and they have found that the mountain may represent an extreme end of volcanic systems and may in fact be unique in the Cascades. Unlike Mount St. Helens, Mount Jefferson and others in this spectacular range, Hood doesn’t explode; it oozes.

Crystal Visions

Kent keeps a piece of Mount Hood in his office. This flat gray rock looks like some kind of exotic concrete. It sparkles with crystals. Irregular, coffee-colored spots about the size of a quarter dot its surface. Dark flecks of hornblende (composed of iron, calcium, silicon and magnesium) are scattered across its surface like pepper on a fried egg.

“When this rock came to the surface,” Kent says, “it was partly liquid. It records information about the last stage of the eruption. But if you want to know more about the long-term conditions in the crust where this magma was being stored, you need to look at the crystals.”

Like tree rings, crystals grow from the inside out over time, says Kent. At their heart are the original minerals — formed out of common elements such as calcium, iron, silicon, magnesium and aluminum. As hot rock pulses up from below, crystals go through warming and cooling phases. Mineral layers form on the outside edges and create a record of temperature, pressure and chemistry. Each ring tells a story about a new pulse of melted rock that cycled the crystal through heating and cooling.

This false color image of a feldspar crystal embedded in a rock from Mount Hood shows the rings generated by pulses of magma from deep in the crust. The outer edge was created during the event that caused the mountain to erupt. (Photo: Adam Kent)

Crystals also trap tiny remnants of some of the original parent material, melted rock that is created as tectonic plates grind against each other. Analysis of these trapped particles — what geologists call “melt inclusions” — provides a picture of the minerals and volatile gases (water, carbon dioxide, sulfur, chlorine and fluorine) that emerge from deep in the crust and can give a mountain shape and personality. When concentrations of those gases are high, explosive eruptions are more likely.

To find out what distinguishes Hood from its neighbors, Kent, Koleszar and their team separate crystals from surrounding rock. In the Oregon State geology lab, they subject samples of the mountain to diamond-tipped saws, acids and devices that pound stones into dust or polish them to a fine sheen (Polishing can be pricey. Grinding pastes that contain diamond particles can cost upwards of $300 for half an ounce). They separate crystals further by exposing rock fragments to magnetic fields or dropping them in dense liquids.

“Some samples are crumbly and fall apart easily,” says Koleszar. “Those are harder to work with. Nice clean pure volcanic glass is great. It polishes like butter. It’s so soft compared to some of the minerals we use.”

Once separated, sliced and mounted on slides, crystals undergo analysis by electron beam that reveals fine structural details or laser and mass spectrometry that tell scientists what trace elements are present in each crystal ring. The result is an accumulation of evidence that allows geologists to explain Hood’s eruption process and compare the mountain to other volcanoes.

More Fizz, No Pop

In a paper published in the Journal of Volcanology and Geothermal Research in 2012, Koleszar and co-authors Kent, William Scott of the USGS and Paul Wallace of the University of Oregon described their findings. They reported that Hood’s magma contains the ingredients for explosive eruptions: magma pumped regularly into the mountain from below, a chemical profile similar to that of other explosive volcanoes and high levels of volatile gases. However, at Hood, those gases tend to escape readily like fizz from an open can of soda. That’s because a 100 degree increase in temperature — an increase that happens as hot rock flows into magma chambers under the mountain — makes the flowing rock five to 10 times less thick.

“Imagine you are blowing into a straw in a milkshake,” says Koleszar. “It’s so thick that the bubbles don’t come out right away, but when they do, they burst and throw stuff up in the air. Compare that to blowing into a straw in a glass of milk. Bubbles just come easily to the surface. That’s more like what we see at Mount Hood.”

Alison Koleszar, left, and Tyler Lomax, a junior from Albany, Oregon, collected rock samples from the 590,000-year-old Cloud Cap lava flow on the eastern side of Mount Hood. Composition of the rocks there is thought to reflect the original parent magma. Koleszar and Lomax also trekked through lava fields on the southern flank where flows are less than 30,000 years old. (Photo: Jeff Basinger)

Mount Hood may be unique in the Cascades, but it joins a select group of volcanoes worldwide (Mount Unzen in Japan, Soufriére Hills Volcano in Montserrat, Mount Dutton in Alaska) that tend to ooze instead of explode. Nevertheless, volcanoes can also demonstrate both types of behavior, and there’s no guarantee that Hood will always operate as it has in the past. Two well-known explosive volcanoes — Mount Pelée in the Caribbean and Mount Pinatubo in the Philippines — have exhibited both types of eruptions. Moreover, geologists know that pulses of hot magma, which occur at Mount Hood, can cause explosions such as the 1980 Mount St. Helens eruption.

“We’re still trying to figure out why Hood only erupts right after a recharge event,” says Koleszar. “It may be that it just doesn’t have the oomph to erupt at other times.

“It seems like such a boring volcano,” she adds. “It erupts the same thing all the time; it doesn’t seem to do anything interesting. It’s an icon, it’s a beautiful volcano and it’s Oregon’s volcano. But when you start to tease things apart a little bit, it does get interesting, exactly because it is so boring.”

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Download an animation of magma rising into a volcanic crater. Scientists can sample the resulting airborne plume to understand how the volcano is likely to erupt. (Produced by the Johnston Ridge Observatory at Mount St. Helens in collaboration with the U.S. Geological Survey)

WeiLi Hong (Photo: Lee Sherman)

When the Earth burps, WeiLi Hong listens. Whether Earth’s gaseous emissions bubble up from “mud volcanoes” on the planet’s surface or seep out of fissures on the ocean floor, the Oregon State University Ph.D. student has his monitoring gear to the ground.

And sometimes, he’s actually in the ground.

“I fell in twice,” Hong admits, describing the hazards of surveying mud volcanoes in his home country of Taiwan. “I was trapped in thick mud up to my waist. There was nothing solid to grab onto. I had to kind of roll across the surface of the mud until I could pull myself out.”

Which brings up a couple of questions: What is a mud volcano, anyway? And why would anyone risk life and limb traipsing around these oddities of nature?

The answer is methane — millions and millions of tons of it trapped in ancient sediments. Under pressure from the bumping and grinding of tectonic plates, the gas migrates upward through Earth’s crust, seeking the atmosphere. Certain countries, such as Taiwan, Indonesia, Pakistan and Azerbaijan, are “burping gas like overfed infants,” to borrow a metaphor from one New York Times writer on the subject of methane emissions. As the methane escapes, creating a slurry of fluids and dissolved solids, volcano-like mud domes mound up across the landscape. They can be as small as a toddler’s backyard swimming pool and as big as several kilometers in diameter.

Mud can act like quicksand. WeiLi Hong needed a helping hand during his research in southern Taiwan. (Photo courtesy of WeiLi Hong)

WeiLi Hong conducts mud volcano science in Taiwan. (Photo courtesy of WeiLi Hong)

But that’s not the only way methane migrates. It comes up through the bottom of the ocean, too. On the seafloor, where it’s super-cold, seeping methane gets locked into ice-like structures called “hydrates,” Hong explains. Studying methane emissions on land, despite the pitfalls, is a walk in the park compared to studying them 2,000 feet beneath the sea.

“With mud volcanoes, we’re looking at how much methane is emitted to the atmosphere,” says Hong, who specializes in chemical oceanography in the College of Earth, Ocean, and Atmospheric Sciences. “With cold seeps, we’re looking at how much methane is emitted to the water column. To do that, we need a vessel with the ability to drill.”

The discomforts of being at sea for two months didn’t deter Hong two summers ago when, along with OSU researcher Marta Torres, he joined an exploratory expedition to Korea’s East Sea hunting for hydrates aboard the research ship Fugro Synergy. His job was to analyze the physical properties of sediment samples taken from the depths.

Methane hydrate will burn when lit. The inset image shows the structure of methane hydrate; the green and grey molecule in the center is methane and the red cage is the ice structure. (Photo courtesy of the National Oceanic and Atmospheric Administration)

For scientists and engineers, this trapped methane presents both threats and opportunities. On one hand, Hong says, melting hydrates could trigger Earth-warming greenhouse-gas emissions and tsunami-causing landslides. On the other hand, methane could be an energy bonanza — if it could be safely harnessed. That’s why the Korean government and the U.S. Department of Energy cosponsored the 2010 Ulleung Basin Gas Hydrate expedition.

“We were looking at porosity, permeability, texture, composition,” he says. “We used an X-ray machine to get 3-D images of the cores.” Opening his laptop, he clicks on a grainy gray image from the bathysphere. As he toggles the image this way and that, he points out traces of long-dead organisms in the long-buried layers. “On the computer,” he notes, “you can rotate the sediment column to see how the geosphere, hydrosphere and biosphere interact.”

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For more information about education abroad opportunities for OSU students, contact the International Degree & Education Abroad (IDEA) office at 541-737-3006.

(Photo: Video, Following the Plastic Trail)

Bear with me; here’s the problem. Plastic mulch — those shiny sheets spread across row upon row of veggies, strawberries and other crops — enables farmers to produce more types and greater quantities of food. It makes farming more profitable, preserves soil moisture, reduces weeds and saves on labor costs. But this type of mulch lasts for only a single growing season. After that, it gets dumped in landfills or is torched in the field — right here in the Willamette Valley and as far away as China.

Mark Ingman and a team of fellow Oregon State students are looking for alternatives to plastic mulch. At a national competition for sustainable technologies sponsored by the U.S. Environmental Protection Agency, they impressed the judges enough to walk away with a promise of a $90,000 grant to develop a cost-effective, biodegradable option made out of flax straw and low-grade wool.

They are now exploring a collaboration with a Canadian company, Naturally Advanced Technologies Inc., which is conducting flax trials in the Willamette Valley in cooperation with Oregon State scientists.

Other students engaged in the project are Kara DiFrancesco, Alison Doniger, Tucker Selko, Dustin DeGeorge, Courtney Holley, Isaiah Miller, Michelle Andersen, Randi Ponce, Veronica Nelson and Caity Clark. Faculty advisers  are Mary Santelmann in Oregon State’s Water Resources Graduate program, Hsiou-Lien Chen and Brigitte Cluver in Design and Human Environment, and James Cassidy in Crop and Soil Science.

Waves from a powerful storm crash into the seawall at Depoe Bay, Oregon. (Photo: Erica Harris, Oregon State University)

If you love big surf, go to Depoe Bay on the Oregon coast during a winter storm. As swells rise and break offshore, winds whip ocean spray high into the air, but the waves move inexorably toward the harbor (the “world’s smallest navigable harbor,” reads a road sign), channel through rocks and, with a resounding shudder, launch a geyser over Hwy. 101. Enthralled tourists standing along the seawall sometimes yelp as they get a cold shower.

It all makes for good fun, but the pounding water carries a warning. Data from offshore buoys indicate that the largest waves are getting bigger. Coupled with slowly rising sea levels and the occasional El Niño, when warm waters pile up along our shores (as much as 19 inches higher than normal, due to thermal expansion), storms are eroding West Coast beaches and undermining bluffs at an increasing rate.

Examples of damage aren’t hard to find. In 2010, a series of El Niño storms “eroded the beaches to often unprecedented levels at sites throughout California and vulnerable sites in the Pacific Northwest,” said coastal geologist Patrick Barnard in a U.S. Geological Survey news release. Damage to a highway lane south of San Francisco cost $5 million to repair.

In 2006, residents of Gleneden Beach found their homes tottering on the edge of a cliff when a weekend storm removed nearly 20 feet of shoreline. In nearby Oceanside, during the El Niño of 1997-98, a 32-home development at The Capes was threatened by collapse of the bluff on which it stood. In southern Oregon during that winter, a storm breached dunes and destroyed Port Orford’s sewage treatment plant drain field. California coastal communities reported more than $100 million in property damage.

In the journal Geophysical Research Letters, Barnard and other West Coast researchers, including Peter Ruggiero of Oregon State University and Jonathan Allan of the Oregon Department of Geology and Mineral Industries (DOGAMI), raised the likelihood of increasing erosion risk in a changing climate and added: “If these trends continue, the combination of large waves and higher water levels, particularly when enhanced by El Niños, can be expected to be more frequent in the future, resulting in greater risk of coastal erosion, flooding, and cliff failures.”

While beaches wax and wane seasonally in a complex dance between land and sea, recent erosion losses have left some Oregon communities more vulnerable to the next storm. DOGAMI’s beach monitoring program has shown that in Tillamook County, beaches have not recovered from the 1997-98 El Niño. They have eroded landward an average of 30 to 60 feet and, in some areas, up to 150 feet. Rockaway Beach alone has lost an estimated 2.5 million cubic yards of sand. At Neskowin, beach retreat has enabled storm waves to threaten homes, flood streets and undermine rock-reinforcement — a.k.a. “rip rap” — in front of the dunes.

Wrestling with Risk

“Neskowin is at the head of the pin in terms of coastal erosion in Tillamook County. The community wishes to be proactive in addressing this problem,” says Mark Labhart, chair of the Neskowin Coastal Hazards Committee and a Tillamook County commissioner. “OSU research papers and direct access to professors have been invaluable in providing factual data on what has been happening in the past and what we might expect in the future so the community, the county and the state can plan for the next steps.”

Waves crawl up against the lower level of a structure in Neskowin, Oregon, during a storm in January, 2008. (Photo: Armand Thibault, Neskowin)

At stake, he adds, are property values, roads, state park facilities and the relaxed quality of life for which the Oregon coast has become famous. Neskowin’s quiet, family-oriented character has lured vacationers for more than a century. According to local historical documents, Sarah Page and her husband settled on what was known as Slab Creek in the 1880s. She opened the first post office and called it Neskowin after she heard a Nestucca Indian refer to the creek by that name, meaning it had plenty of fish.

Today, the community has 408 homes (less than a quarter of which are occupied year around), a golf course and a condominium development, the Proposal Rock Inn. Nestled against Cascade Head to the south, Neskowin mirrors much of coastal Tillamook County, which has the highest percentage of second homes of all the state’s shoreline counties, according to the Oregon Coastal Zone Management Association (OCZMA).

Dedicated to protecting this idyllic enclave is a local group appointed by the county commission in 2009. The Neskowin Coastal Hazards Committee is composed of property owners and local and state officials and facilitated by Pat Corcoran, a coastal hazards specialist with Oregon Sea Grant. It has met with Ruggiero, Allan and other scientists. It has reviewed options (known as “Hazard Alleviation Techniques” or HATs) for reducing erosion hazards. With Corcoran’s help, it identified emerging research and delved into erosion processes and trends.

Working with Mitch Rohse, a planning consultant from Salem, the committee published a proposed legal policy in 2011 for counties to deal with the mounting risks: Adapting to Coastal Erosion Hazards in Tillamook County: A Framework Plan. Local planners and the county planning commission must review the document before it goes to the county commission for approval. Concurrently, the committee has raised more than $27,000 from private contributors, the Neskowin Homeowners Assn. and the Oregon Dept. of Land Conservation and Development for an engineering analysis of options and costs to protect the shoreline.

A first for Oregon, the draft framework plan calls on the county to adopt policies that help communities reduce their vulnerability to storm damage and erosion. Reflecting current state and local regulations, it draws from a variety of scientific sources, including former OSU master’s student Heather Baron’s 2011 thesis, in which she focused on “coastal hazard zones.” For her degree in Marine Resource Management, she evaluated the probability of erosion in each zone for 18 different climate change scenarios. Each scenario reflects a combination of risk factors: sea level rise, extreme wave heights and El Niño frequency and intensity. Her work builds on research by Ruggiero, Allan and their colleagues, who have used beach, wave and landscape data to define such zones along the Oregon coast.

If the plan were approved, properties in each zone would be subject to standards that reflect their vulnerability to the risk of future storm damage. Neskowin committee members expect that idea to generate debate over issues from development rights to property values. “Any time you put colored lines on a map that potentially affect property values, you get people’s attention in a hurry,” says Labhart.

Coastal Change

The threat faced by Neskowin and other communities doesn’t arise over night. It grows gradually from a series of seemingly harmless events, chief among them the construction of homes and condos and the seawalls that protect them. “A recent storm may have washed away a beach or destroyed homes lining the shore,” wrote retired OSU coastal oceanographer Paul Komar in The Sciences in 2000, “but merely blaming the weather is simplistic. Almost always, subtle factors have been acting over time to weaken the coast and make it more susceptible; the storm, when it comes, simply delivers the coup de grâce.”

Waves pound a beach and structure between Depot Bay and Boiler Bay on the Oregon coast. (Photo: Erica Harris, Oregon State University)

Neskowin’s case is puzzling, says Komar. When he started investigating erosion problems in the 1970s, Neskowin homeowners had problems with too much sand building up the dunes, blocking ocean views and even threatening to bury homes. “The change to erosion began with the 1982-83 El Niño and accelerated during the ‘one-two punch’ of the 1997-98 El Niño and storms of the following winter,” he says. Today, he adds, the community is a “classic example of ‘hot spot’ El Niño erosion. Normally during the next few years following an El Niño winter, we expect the beach sand to be carried back to the south by the ‘normal’ waves, but this has not happened yet at Neskowin, and it’s not clear why it hasn’t.”

Over the last decade, with support from Oregon Sea Grant and agencies such as the National Oceanic and Atmospheric Administration, scientists have been zeroing in on those subtle factors. Basic questions motivate them: How do coastal systems work? How do currents carry sand onto and off a beach, piling it up in some years and draining it away in others? Is sand accumulating on the coast or moving permanently into the deep ocean?

Just as importantly, they are providing communities like Neskowin with the knowledge to reduce property risks in the future. “We’re getting great data about the Oregon coast now. Compared to what we had 10 or 15 years ago, the observational data we have today are like night and day,” says Onno Husing, executive director of the OCZMA.

Citizens, elected officials and policymakers can see those data at the click of a mouse. Researchers regularly profile beaches from Gold Beach to Astoria and publish charts that show present and past sand heights relative to mean low and high water levels (see “Beach and Shoreline Mapping” at www.nanoos.org). They monitor wave heights and wave “run-up” on beaches. They estimate future flood risks and how many homes, roads and businesses are in harm’s way. And they meet with citizens to share the results.

Although the broad direction of changes over at least the last decade is clear, Ruggiero emphasizes that uncertainty casts a shadow over the likelihood that any home or community will suffer damage in the future. The range of estimates for climate change only adds to the difficulty of forecasting future risk.

Speaking of just one factor, increasing wave heights, he says: “Attributing it to climate change is very difficult. I don’t do that, but the bottom line is that the waves have increased over the last several decades, and that could be for a variety reasons. Any time you look way out into the future, uncertainty is huge.”

What is certain is that big waves will continue to hit the West Coast and attract sightseers to places like Neskowin, Rockaway and Depoe Bay. How coastal communities will adapt is an open question.

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Read a National Academy of Sciences report, Sea-Level Rise for the Coasts of California, Oregon, and Washington: Past, Present, and Future (2012)

Three Sisters in the Oregon Cascades (Photo: University Marketing)

That’s what happened in early November 2006, says OSU geoscientist Anne Nolin. On virtually every Cascade peak from Mt. Rainier in Washington to Mt. Hood in Oregon, a “perfect storm” of driving rain, balmy temperatures and receding glaciers sent torrents of rock and mud tearing downhill.

“It was raining almost to the top of Mt. Hood,” recalls Nolin, an internationally known expert in mountain hydroclimatology. On her laptop, she clicks open a photo of Mount Hood with one of her graduate students standing beside a jumble of debris that had spewed out of Eliot Creek into a grove of evergreens during the storm, which dumped over 13 inches of rain on Mt. Hood in 36 hours.

“This area used to be soft forest duff,” Nolin explains, pointing to the photo. “Now it’s full five feet in boulders and logs.”

Collecting data with sophisticated technologies (satellites, lasers and computer models), as well as traditional methods (boots on the ground), Nolin is leading an investigation that will more fully describe the forces energizing alpine debris flows.

“There’s an enormous amount of sediment up there — pyroclastic debris from volcanoes, till ground up by glaciers,” she says. “Once it’s no longer held in place by the ice, it becomes unstable. Add water, and these unstable sediments are mobilized.”

The study, supported by more than $350,000 in National Science Foundation (NSF) stimulus funds, also will help foresters, park managers and mountain communities better predict events like the 2006 deluge, which washed out bridges, swept away campgrounds, closed roads and set the stage for future floods by choking river channels.

Pineapple Express

Snow is Nolin’s medium. Practically born with skis on her feet, she has plied the slopes from Killington Mountain in Vermont, near where her family has a home, to Mt. Hutt in New Zealand, where she spent three and a half months of her 2009-2010 sabbatical. The other eight months she lived (and skied) in the Vaud and Valais regions of Switzerland. (The Northern and Southern Hemispheres together gave her back-to-back winters — something only a lifelong snow lover would deem delightful.) While overseas, she gave a flurry of presentations about debris flows, as well as conferring with fellow researchers at the University of Canterbury in Christchurch, the Ecole Polytechnique Federale de Lausanne and the University of Zurich.

The Cascades will see more rain, less snow and changing water flows as climate shifts precipitation patterns, says Anne Nolin of OSU’s Dept. of Geosciences. In addition to analyzing debris flow risks, Nolin focusing on snowpack and water availability in the McKenzie River Basin. (Photo: Karl Maasdam)

All of these scientists are seeing the same thing on their local mountaintops: a steady nibbling away of glacial edges. Satellite images of Hood and Rainier show glaciers shrinking by 14 percent between 1987 and 2005, Nolin reports. That’s a loss of nearly 1 percent ice volume per year.

It is at this ragged glacial edge, where ice is fragmented and meltwater is leaking down the ultra-steep terrain of towering peaks, that most debris flows begin. Nolin and her team are trying to pin down the triggering mechanisms. One culprit could be the so-called Pineapple Express — those notorious storms nicknamed for the warm temperatures and monsoon-like quantities of rain they bring from their origins in the tropical Pacific. They are examples of “atmospheric rivers” — airborne water plumes that shoot extraordinary amounts of vapor through the atmosphere. Nolin describes them as “laser beams of moisture,” which blast into the Northwest from time to time, including the 2006 storm that ranked as the decade’s worst.

“We’re trying to understand the character of these storms and their impact on mountain sediments,” she says. “Basically, we want to know how climate change affects rain-induced debris flows in the Northwest and other mountain regions worldwide.”

After Year One of the three-year study, Nolin and her team of colleagues and graduate students have found a clear link between debris flow events and unusually high freezing levels — the elevation where precipitation falls as snow instead of rain.

“The freezing altitudes of nearly all the storms that caused debris flows are at least one standard deviation higher than other significant rainfall events occurring in the same season,” Nolin writes along with her co-investigators Stephen Lancaster, an OSU geomorphologist, and Gordon Grant, a courtesy professor from the U.S. Forest Service, in their annual report to NSF. “Further, nearly all debris-flow events were coupled with … atmospheric river-like conditions.”

Yet because of the complex interplay of mountain systems, storm dynamics and debris-flow mechanics, Nolin says, “the conclusive story continues to elude us.”

Upslope, Downslope

“Water flows downhill, but policy flows uphill,” Nolin told members of the international Mountain Research Initiative in Perth, Scotland, last fall.

On the “upslope-downslope continuum,” it’s the big population centers in the valleys and on the coasts that pass the laws and set the agendas for timber harvest, land use, energy resources, air quality, water allocation and just about everything else that affects the highlands, she explained.

Policy isn’t the only thing that rises. Greenhouse gasses produced by cities and by fossil fuel users in the lowlands have caused temperatures to rise in the mountains. Research reveals that this warming is altering the foothills and forests of Oregon’s Cascades in measurable ways. Spring is arriving a full month sooner than it did 50 years ago in some parts of the H.J. Andrews Experimental Forest, Nolin says, citing the research of OSU atmospheric scientist Christoph Thomas. Winters’ final frosts, he found, are falling ever earlier on the calendar. Water levels in the McKenzie River are dropping. Lower elevation snowpack — accumulated layers of snowfall that build up and compact during the winter — is disappearing.

“When snow melts earlier, we lose water storage,” says Nolin. “Snowpack is a reservoir for us.”

In Oregon’s Hood River Valley, 50 to 80 percent of the water that irrigates crops comes from Mt. Hood’s glaciers and snowpack. If early melting trends continue, that priceless meltwater is in danger of dwindling by early- to mid-summer, leaving farmers in short supply during the hottest months when they need it most.

“Climate change,” Nolin says, “disproportionately affects mountain regions.” One reason is found in the physical properties of light and frozen H2O — properties she studied along with satellite remote sensing as a Ph.D. student at U.C. Santa Barbara. After having previously worked as a soil and water scientist, she became entranced by the elegant physics of light interacting with ice particles.

“Soil and snow are both particulate, porous substances,” she says. “But snow is so much more simple and clean. Radiative transfer theory is a very straightforward way to monitor snow from satellites.”

In fact, the glittering white of snow and ice is what explains the vulnerability of mountains to climate change. Whiteness, Nolin explains, reflects sunlight back into the atmosphere. As light-reflecting snowcaps and ice sheets shrink, more sunlight gets absorbed into the earth instead of bouncing off.

Melting accelerates as ever more light and heat are captured and held. Scientists call this phenomenon the “ice-albedo feedback.” As a vicious cycle, it causes temperatures to actually rise faster in ice-laden places than elsewhere on the planet.

Those ice-laden places include the North Atlantic island of Greenland, where as an early-career scientist, Nolin spent several summers studying polar climatology.

“It’s flat and white as far as you can see,” she recalls. But if that sounds like a complaint about the frozen landscape, she quickly sets the record straight. “It glitters,” she says. “It’s very pretty.”

On the Web: See more about OSU’s Mountain Hydroclimatology Research Group.