By Lee Anna Sherman
One is a mountaineer investigating amphibians. Another is a world traveler studying birds. The third came from China to study ocean-atmosphere interactions, while the fourth is an elite athlete interested in the economics of rangelands.
What links these four students and their diverse scientific interests is climate change. Lindsey Thurman, Sarah Frey, Sihan Li and Seth Wiggins have been granted fellowships from the Northwest Climate Science Center, a program of the U.S. Department of the Interior hosted by the Oregon Climate Change Research Institute (OCCRI) at Oregon State University.
“The purpose of the fellowships is to support promising graduate students whose research is relevant to the Climate Science Center,” says Phil Mote, OCCRI director.
Their academic talents are exceeded only by the energy with which they engage the world. Here are their stories.
Little Nooks and Crannies
Her forest-green Toyota pickup was packed to the gills when Sarah Frey climbed in and steered toward I-90, trailer in tow. The Vermonter was in a bit of a daze. A chance encounter barely a month before had launched her on an unplanned journey across the United States, destination, Oregon.
It all started in 2008 at an American Ornithologists’ Union conference in Portland, where Frey ran into OSU forest ecologist Matt Betts, an acquaintance from an earlier population-modeling workshop. After five years of tramping around the Americas and Pacific Islands doing fieldwork for conservation nonprofits — studying hawk migration in Nevada, banding owls in Michigan, investigating avian pox among forest birds in Hawaii, tracking tropical birds in Ecuador — she had recently finished her master’s thesis at the University of Vermont on Bicknell’s thrush, a rare, high-elevation species. She hadn’t yet mapped out her next move. Then Betts sprung a fellowship offer.
“How about starting your Ph.D. next month?” he asked. A few weeks later, she was enrolled in the College of Forestry with a minor in Ecosystem Informatics.
For the next three field seasons, she monitored birds in the H.J. Andrews Experimental Forest. From mid-May through early July, she and other researchers climbed the rugged slopes, from creek bed to mountaintop, documenting behaviors and population densities of about 50 species. “We went out to 184 sites, stood, listened, and looked for 10 minutes at each site,” she explains. “During 2011, we carried out fiberglass poles and PVC pipe to all of the points for installing temperature sensors.”
Enduring the brutal conditions of fieldwork is an occupational hazard for Frey. Ever since the iconic behavioral ecologist Bernd Heinrich (Mind of the Raven) turned her on to birds during an ornithology field trip when Frey was an undergrad, she has thrown herself into more adventures than Indiana Jones. Braving the tropical forests of Queensland, Australia, for a study-abroad program was one. Another was her Bicknell’s thrush study, which took her up and down a different Appalachian mountain every day for two breeding seasons. Her studies also have taken her to Switzerland where she recently spent two months working with a statistical modeler at the Swiss Ornithological Institute.
Frey’s OCCRI-funded research challenges certain longstanding assumptions that underpin today’s species-climate models. Typically, these models are based on “bioclimatic envelopes” — that is, the mix of temperatures, precipitation levels and other climate variables within which species thrive. She wants to know what other factors might be driving species extinctions and biodiversity in a time of shifting climate. How important is vegetation, for instance? What about competition among species? Where does predation fit in? How do microclimates help birds adapt to climate change?
One of the things she’s investigating is the role of temperature in small-scale species distributions. The buffering capacity of “microclimatic refugia” (habitat havens she characterizes as “little nooks and crannies”) in mountainous terrain could be critical as birds make adjustments to a fluctuating environment in nesting, breeding and foraging.
“I’m trying to tease apart the main drivers of where species occur,” she says. “Most scientists think climate is the primary driver at large scales, while vegetation and other species are the main drivers at small scales.”
To find out, she compared the influence of microclimate on distribution dynamics for three species with different migratory strategies: hermit warbler (a neotropical migrant), chestnut-backed chickadee (a resident) and Pacific wren (a partial migrant).
“There have been very few rigorous tests of these alternative hypotheses,” Frey notes. “Uncovering the relative importance of different drivers of species distribution — climate, land cover, competitors, predators — is critical for both ecological theory and environmental policy.”
Worldwide Weather Warriors
College student Sihan Li gazed in astonishment at the terracotta warriors, massed by the thousands on a silent, earthen battlefield near Xi’an in central China. Little did the Yunnan University undergrad know that soon she would be marshaling her own army from a computer lab in Oregon. But unlike Emperor Qin’s clay troops, built to do battle in the afterlife, Sihan Li’s flesh-and-blood legions are taking up arms against the here-and-now threat of climate change. And instead of spears and swords, her climate warriors are wielding keyboards and barometers.
Li’s army, enlisted by a global project called climateprediction.net, comprises more than 50,000 weather geeks. They have volunteered to collect information on local precipitation, temperature, humidity and other weather events and load it onto their home computers. Li’s job is to analyze the data from the western United States — one of three regions being studied worldwide with funding from the U.S. Geological Survey. To do that, she is using BOINC (Berkeley Open Infrastructure for Network Computing), a software system for volunteer computing.
“Usually, communities feel removed from the research going on around them,” notes Li, who goes by Meredith. “But volunteers for climateprediction.net become personally involved and committed to the project.”
The experiment, characterized by Li as “unprecedented” in its scope and reach, is a perfect fit for this 23-year-old Ph.D. student in OSU’s College of Earth, Ocean, and Atmospheric Sciences. To the young atmospheric scientist, only the colorful richness of humanity rivals topics like wind-ocean circulation dynamics and heat-flux transfer on the list of fascinating things to study and experience. As an undergraduate, Li explored the far corners of China with a train ticket and a backpack whenever she wasn’t taking classes and working on regional climate modeling. The ancient city of Xi’an, home of the Terracotta Army, enchanted her with its palpable sense of history. “You can almost smell the culture in the air,” she says.
Like humanity, climate is infinitely complex. So far, computer models designed to predict future climate scenarios have been hobbled by one of two problems: too broad a scope that glosses over the finer details of geography, or too narrow a range that fails to capture the larger context. The army of weather volunteers will remedy these deficiencies, Li says, by collecting data broadly and finely simultaneously. The result will be “super ensembles” — suites of large-scale simulations — for the western U.S., Europe and southern Africa.
“This research,” says Li, “is not only scientifically groundbreaking, but likely to provide the greatest value to date in assisting the western region as we attempt to cope with and plan for climate change.”
Along with Oxford University, OCCRI’s partner on the project, OSU is consulting closely with stakeholders, including the U.S. Bureau of Land Management, the California Department of Water Resources and the Water Utility Climate Alliance.
“Science is, in the end, to be of service to people — to make the world a better place for people to live in,” says Li.
Carbon, Cattle and Costs
These days, Seth Wiggins spends long hours staring at a computer screen in his lab at OSU. But the master’s student is not a natural habitue of chairs, swivel or otherwise. In 2009 his dead-accurate aim and rocket-fast arm won him a gold medal in Ultimate Frisbee at the World Games in Taiwan. The next year he pedaled his Giant OCR2 road bike from Seattle to New York, spinning 3,000 miles in six weeks, solo. The biggest challenge, he says, was getting enough calories. “I would go to these all-you-can-eat pancake places and eat them out of business,” he reports. “My record was 23.” Pancakes, that is. With butter and syrup.
Soon after his cross-country ride, Wiggins got serious about his other passion — saving the planet — and enrolled in graduate school. But instead of choosing a field like forest ecology or conservation biology, the 27-year-old from Corvallis is taking a less-usual path to planetary protection: economics.
“What I care about are environmental issues, specifically climate change,” says Wiggins, who earned his bachelor’s in econ and international studies at the University of Oregon. “But in this society, things don’t happen unless money is attached.”
Take CO2 reduction, for example. Attaching a dollar figure to greenhouse gasses is the idea behind cap and trade, which lets companies exchange carbon credits on the free market. In Oregon, where rangelands comprise about one in nine acres, grasses soak up carbon dioxide by the ton. By capturing and holding (“sequestering”) CO2 from the atmosphere, Oregon’s vast rangelands create a powerful sink for pollutants that would otherwise be warming the atmosphere. If policymakers were to offer economic incentives to ranchers, Wiggins suggests, the state could lock up significant quantities of emissions every year.
“This is an enormous land resource,” says Wiggins. “Carbon sequestration on rangelands could potentially have a huge effect.”
To test that potential in the Pacific Northwest, he is looking at ranching operations across Oregon, Washington and Idaho with at least 100 acres and cattle sales grossing $10,000. Using a statistical model designed by Professor John Antle in the Department of Agricultural and Resource Economics, Wiggins is analyzing data from the most recent Census of Agriculture to weigh various assumptions — costs, returns, profits, and so on — that underlie the sequestration concept. The study’s goal is to find the optimal price point where ranchers could be persuaded to join a sequestration program and improve their land management practices.
“Currently, much of the rangeland is overgrazed,” says Wiggins. “It’s cheaper for ranchers to add more cows than to maintain healthy grasslands.”
Attractive economic incentives would encourage ranchers to adopt eco-friendly methods, such as rotational grazing or intensive pasturing — methods that allow soils to absorb carbon in the atmosphere, according to Wiggins. The way he sees it, practices that are affordable as well as environmentally sound allow people to align their actions with their values without taking a hit in the pocketbook.
“Right now there’s a disconnect between our values and our actions,” he says. “No one wants to leave a deteriorating environment to generations going forward, but many people act as if they do. Figuring out how to get people to act in accordance with their values seems incredibly interesting to me.”
Blue Crabs to Cascades Frogs
The little girl with the sunburned nose and whorl of sun-bleached hair felt as much at home swimming and diving in Florida’s Santa Rosa Sound as did the blue crabs she loved to trap. Since those carefree days on the Gulf Coast, Lindsey Thurman has stalked wildlife both cold-blooded and warm. She has monitored sea turtle nests from Pensacola to Alligator Point as an undergraduate at the University of Florida, Gainesville. Netted freshwater fish in Okefenokee National Wildlife Refuge for the Florida Museum of Natural History. Sampled tissues from snakes and other reptiles in Ocala National Forest for the U.S. Geological Survey. Tracked carnivores in California’s Sierra Nevada range for a U.S. Forest Service study.
And she did all this before she was admitted to graduate school at OSU.
“I’m a field biologist at heart,” says the Ph.D. student in the Department of Fisheries and Wildlife, which she chose because of its No. 1 national ranking. “I’m fascinated by phylogeny — how species are arranged on the tree of life. I like the challenge, physically and mentally. I like the serenity of being out there by myself.”
These days, “being out there” means trekking through the Cascades, her backpack stuffed with topo maps and sampling kits for collecting live amphibians. In alpine ponds, creek beds and leaf litter, she seeks to discover how high-elevation frogs and salamanders are coping with climate change. With her yellow Lab, Sierra, loping merrily beside her, the 25-year-old is already blazing new trails in amphibian research. Her master’s project, carried out under the guidance of Assistant Professor Tiffany Garcia, revealed that long-toed salamanders have modified their egg-laying behavior to protect their progeny from the interplay of mounting temperatures and UV (ultraviolet) radiation, which are dangerously strong in the upper reaches. Instead of laying masses of eggs at the water’s surface, Thurman discovered, the salamanders are depositing their eggs singly under protective rocks or silt at high elevation.
For her new study, she’s pondering a wider range of variables — what she calls the “litany of threats” to the survival of mountain-dwelling amphibians.
“The impacts of environmental stressors on amphibian populations typically have been studied independently,” Thurman notes. “My study will contribute a broader analysis of climate change variables on multiple species across diverse, freshwater ecosystems.”
Scientists know that amphibians’ permeable skin and soft-shelled eggs make them hypersensitive to changes in temperature, moisture and UV rays. But there are all sorts of other questions demanding answers, Thurman says. For example, How do the animals’ “plastic” (quickly adaptable) developmental traits mitigate climate stressors? What happens to animals living in ephemeral ponds and meadows (those that dry up part of the year)? What is the impact of inter-species competition?
“I’ve always wanted to look at these variables on a landscape scale,” says Thurman. “Climate change is a global issue, and the variables are not independent. It’s hard to tease them apart.”
To find out how amphibians respond to the synergies of climate and high elevation, her ambitious study has three parts: field work, lab experiments and theoretical modeling. In the field, she will document frog and salamander populations in three watersheds at elevations above 1,000 meters from southern Oregon to southern British Columbia. In the lab, she will run climate and population scenarios (wetter, drier, hotter, more animals per tank) on the Cascades frog, the western toad, the Pacific chorus frog and the long-toed salamander. In the computer lab, she will use models to predict climate-driven changes in ecology and species distribution.
“Mountain amphibians are losing suitable breeding habitat rapidly,” Thurman says. “These species are going extinct at a disproportionate rate worldwide. With new baseline data, land managers will be able to fast-track conservation strategies for high-elevation freshwater ecosystems in time to make a difference.”