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    Landslides shaped a hidden landscape within Yellowstone

    DENVER — A hidden landscape riddled with landslides is coming into focus in Yellowstone National Park, thanks to a laser-equipped airplane.

    Scientists of yore crisscrossed Yellowstone on foot and studied aerial photographs to better understand America’s first national park. But today researchers have a massive new digital dataset at their fingertips that’s shedding new light on this nearly 1-million-hectare natural wonderland.

    These observations of Yellowstone have allowed a pair of researchers to pinpoint over 1,000 landslides within and near the park, hundreds of which had not been mapped before, the duo reported October 9 at the Geological Society of America Connects 2022 meeting. Most of these landslides likely occurred thousands of years ago, but some are still moving.

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    Mapping Yellowstone’s landslides is important because they can cripple infrastructure like roadways and bridges. The millions of visitors that explore the park each year access Yellowstone through just a handful of entrance roads, one of which recently closed for months following intense flooding.

    In 2020, a small aircraft flew a few hundred meters above the otherworldly landscape of Yellowstone. But it wasn’t ferrying tourists eager for up close views of the park’s famous wolves or hydrothermal vents (SN: 7/21/20, SN: 1/11/21). Instead, the plane carried a downward-pointing laser that fired pulses of infrared light at the ground. By measuring the timing of pulses that hit the ground and reflected back toward the aircraft, researchers reconstructed the precise topography of the landscape.

    Such “light detection and ranging,” or lidar, data reveal details that often remain hidden to the eye. “We’re able to see the surface of the ground as if there’s no vegetation,” says Kyra Bornong, a geoscientist at Idaho State University in Pocatello. Similar lidar observations have been used to pinpoint pre-Columbian settlements deep within the Amazon jungle (SN: 5/25/22).

    The Yellowstone lidar data were collected as part of the 3D Elevation Program, an ongoing project spearheaded by the United States Geological Survey to map the entirety of the United States using lidar.

    Bornong and geomorphologist Ben Crosby analyzed the Yellowstone data — which resolve details as small as about one meter — to home in on landslides. The team searched for places where the landscape changed from looking relatively smooth to looking jumbled, evidence that soil and rocks had once been on the move. “It’s a pattern-recognition game,” says Crosby, also of Idaho State University. “You’re looking for this contrast between the lumpy stuff and the smooth stuff.”

    The researchers spotted more than 1,000 landslides across Yellowstone, most of which were clustered near the periphery of the park. That makes sense given the geography of Yellowstone’s interior, says Lyman Persico, a geomorphologist at Whitman College in Walla Walla, Wash., who was not involved in the research. The park sits atop a supervolcano, whose previous eruptions blanketed much of the park in lava (SN: 1/2/18). “You’re sitting in the middle of the Yellowstone caldera, where everything is flat,” says Persico.

    But steep terrain also abounds in the national park, and there’s infrastructure in many of those landslide-prone areas. In several places, the team found that roads had been built over landslide debris. One example is Highway 191, which skirts the western edge of Yellowstone.

    An aerial image of U.S. Highway 191 near Yellowstone shows barely perceptible signs of a long-ago landslide. But laser mapping reveals the structure and extent of the landslide in much greater detail (use the slider to compare images). It’s one of more than 1,000 landslides uncovered by new maps.

    It’s worth keeping an eye on this highway since it funnels significant amounts of traffic through regions apt to experience landslides, Bornong says. “It’s one of the busiest roads in Montana.”

    There’s plenty more to learn from this novel look at Yellowstone, Crosby says. Lidar data can shed light on geologic processes like volcanic and tectonic activity, both of which Yellowstone has in spades. “It’s a transformative tool,” he says. More

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    Heat waves in U.S. rivers are on the rise. Here’s why that’s a problem

    U.S. rivers are getting into hot water. The frequency of river and stream heat waves is on the rise, a new analysis shows.

    Like marine heat waves, riverine heat waves occur when water temperatures creep above their typical range for five or more days (SN: 2/1/22). Using 26 years of United States Geological Survey data, researchers compiled daily temperatures for 70 sites in rivers and streams across the United States, and then calculated how many days each site experienced a heat wave per year. From 1996 to 2021, the annual average number of heat wave days per river climbed from 11 to 25, the team reports October 3 in Limnology and Oceanography Letters.

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    The study is the first assessment of heat waves in rivers across the country, says Spencer Tassone, an ecosystem ecologist at the University of Virginia in Charlottesville. He and his colleagues tallied nearly 4,000 heat wave events — jumping from 82 in 1996 to 198 in 2021 — and amounting to over 35,000 heat wave days. The researchers found that the frequency of extreme heat increased at sites above reservoirs and in free-flowing conditions but not below reservoirs — possibly because dams release cooler water downstream.

    Most heat waves with temperatures the highest above typical ranges occurred outside of summer months between December and April, pointing to warmer wintertime conditions, Tassone says.

    Human-caused global warming plays a role in riverine heat waves, with heat waves partially tracking air temperatures — but other factors are probably also driving the trend. For example, less precipitation and lower water volume in rivers mean waterways warm up easier, the study says.

    “These very short, extreme changes in water temperature can quickly push organisms past their thermal tolerance,” Tassone says. Compared with a gradual increase in temperature, sudden heat waves can have a greater impact on river-dwelling plants and animals, he says. Fish like salmon and trout are particularly sensitive to heat waves because the animals rely on cold water to get enough oxygen, regulate their body temperature and spawn correctly.

    There are chemical consequences to the heat as well, says hydrologist Sujay Kaushal of the University of Maryland in College Park who was not involved with the study. Higher temperatures can speed up chemical reactions that contaminate water, in some cases contributing to toxic algal blooms (SN: 2/7/18). 

    The research can be used as a springboard to help mitigate heat waves in the future, Kaushal says, such as by increasing shade cover from trees or managing stormwater. In some rivers, beaver dams show promise for reducing water temperatures (SN: 8/9/22). “You can actually do something about this.” More

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    Tree-climbing carnivores called fishers are back in Washington’s forests

    Holding an antenna above his head, Jeff Lewis crept through an evergreen forest in the Cascade mountains, southeast of Seattle. As he navigated fallen fir logs and dripping ferns, he heard it: a faint “beep” from a radio transmitter implanted in an animal code-named F023.

    F023 is a fisher (Pekania pennanti), an elusive member of the weasel family that Lewis fondly describes as a “tree wolverine.” Resembling a cross between a cat and an otter, these sleek carnivores hunt in forests in Canada and parts of the northern United States. But fur trapping and habitat loss had wiped out Washington’s population by the mid-1900s.

    Back in 2017 when Lewis was keeping tabs on F023, he tracked her radio signal from a plane two or three times a month, along with dozens of other recently released fishers. Come spring, he noticed that F023’s behavior was different from the others.

    Her locations had been clustered close together for a few weeks, a sign that she might be “busy with babies,” says Lewis, a conservation biologist with the Washington Department of Fish and Wildlife. He and colleagues trekked into the woods to see if she had indeed given birth. If so, it would be the first wild-born fisher documented in the Cascades in at least half a century.

    As the faint beeps grew louder, the biologists found a clump of fur snagged on a branch, scratch marks in the bark and — the best clue of all — fisher scat. The team rigged motion-detecting cameras to surrounding trees. A few days later, after sifting through hundreds of images of squirrels and deer, the team hit the jackpot: a grainy photo of F023 ferrying a kit down from her den high in a hemlock tree. The scientists were ecstatic.

    “We’re all a bunch of little kids when it comes to getting photos like that,” Lewis says.

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    Chasing babies

    This notable birth came during the second phase of a 14-year fisher reintroduction effort. After 90 fishers were released in Olympic National Park from 2008 to 2010, the project turned its focus east of Seattle, relocating 81 fishers in the South Cascades (home to Mount Rainier National Park) from 2015 to 2020, and then 89 fishers in the North Cascades from 2018 to 2020. The animals were brought in from British Columbia and Alberta. The project concluded last year, when researchers let loose the final batch of fishers.

    Baby animals are the key measure of success for a wildlife reintroduction project. As part of Washington’s Fisher Recovery Plan, biologists set out to document newborn kits as an indicator of how fishers were faring in the three relocation regions.

    Before F023’s kit was caught on camera in May 2017, biologists had already confirmed births by seven relocated females on the Olympic Peninsula, where the whole project began. Two of the seven females had four kits, “the largest litter size ever documented on the West Coast,” says Patti Happe, wildlife branch chief at Olympic National Park. Most females have one to three kits.

    Lewis is often asked, why put all of this effort into restoring a critter many people have never heard of? His answer: A full array of carnivores makes the ecosystem more resilient.

    Happe admits to another motive: “They’re freaking adorable — that’s partly why we’re saving them.”

    This agile member of the weasel family is a fearsome predator. Fishers are one of the few carnivores that can hunt and kill quill-covered porcupines.EMILY BROUWER/NPS (CC BY 2.0)

    The missing piece

    Contrary to their name, fishers don’t hunt fish, though they’ll happily munch on a dead one if it’s handy. They mainly prey on small mammals, but they also eat reptiles, amphibians, insects, fruit and carrion. About a meter long, males weigh up to six kilograms, about twice as much as females. Fun facts: Females raise young high above the forest floor in hollowed-out spaces in tree trunks. Fishers can travel face-first down tree trunks by turning their hind feet 180 degrees. They have wickedly sharp teeth and partially retractable claws. And they’re incredibly agile, leaping up to two meters between branches and traveling as much as 30 kilometers in a day.

    Fishers’ stubby legs and unique climbing skills make them a threat to tree-climbing porcupines. It isn’t pretty: A fisher will force the quill-covered animal down a tree and attack its face until it dies from blood loss or shock. Then the fisher neatly skins the prickly prey, eating most everything except the quills and bones.

    These camera trap photos, taken in April 2021, show female fisher F105 carrying one of her four kits down from her tree den near Lake Wenatchee in the North Cascades.NPS

    But these fearsome predators were no match for humans. In the 1800s, trappers began targeting fishers for their fur. Soft and luxuriant, the glossy brown-gold pelts were coveted fashion accessories, selling for as much as $345 each in the 1920s. This demand meant fishers disappeared not only from Washington, but from more than a dozen states across the northern United States. Once fisher populations plummeted, porcupines ran rampant across the Great Lakes region and New England. This wreaked havoc on forests because the porcupines gobbled up tree seedlings.

    Hoping to keep porcupine populations in check, private timber companies partnered with state agencies to bring fishers back to several states in the 1950s and 1960s. Thanks to these efforts and stricter trapping regulations, fishers are once again abundant in Michigan, Wisconsin, New York and Massachusetts.

    But in Washington, like most of the West, fisher numbers were still slim. By the turn of the 21st century, no fisher had been sighted in the state for over three decades.

    As in the Midwest and New England, private timber companies in Washington supported bringing back fishers. Although porcupines are uncommon in Washington, mountain beavers — a large, primitive rodent endemic to the Pacific Northwest — fill a similar role in Washington’s evergreen forests: They eat tree seedlings. And fishers eat them.

    By 2006, the state hatched a plan to bring the animals in from Canada. “It was a big opportunity to restore a species,” Lewis says. “We can fix this.”

    [embedded content]
    This 2009 camera trap vídeo from Olympic Peninsula shows fisher F007 scaling a cedar tree and carrying her four kits to the forest floor, one at a time

    A new home

    Like the other Canadian fishers moved to Washington, F023’s relocation story began when she walked into a box trap in British Columbia, lured by a tasty morsel of meat. The bait had been set by local trappers hired by Conservation Northwest, a nonprofit that is one of the recovery project’s three main partners, along with Washington Fish and Wildlife and the National Park Service. After veterinarians checked her health and administered vaccines and antiparasitics to help her survive in her new home, F023 received a surgically implanted radio transmitter and was driven across the border.

    She was met by members of the fisher recovery team, who released her just south of Mount Rainier National Park. The forest’s towering Douglas fir, western red cedar and western hemlock trees were full of cubby holes and cavities to hide in, and the undergrowth held plenty of small mammals to eat. At the release, upward of 150 people gathered around F023’s box, part of the team’s effort to engage the public in championing fisher recovery. Everyone cheered as a child opened the door and the furry female bounded into the snowy woods, out of sight in a flash.

    The team monitored each relocated fisher for up to two years to see if the project met key benchmarks of success in each of the three regions: more than 50 percent of the fishers surviving their first year, at least half establishing a home range near the release site, and a confirmed kit born to at least one female.

    “We met those marks,” says Dave Werntz, science and conservation director at Conservation Northwest.

    The effort may have been aided by a series of bypasses built over and under a roughly 25-kilometer stretch of Interstate 90 east of Seattle. One of these structures is the largest wildlife bridge in North America, an overpass “paved” with forest. In 2020, a remote camera caught an image of what looks like a fisher moving through one of the underpasses.

    Speeding vehicles on busy highways pose a threat to fishers and other migrating wildlife. This new bridge east of Seattle is “paved” with trees and plants to let animals safely cross I-90 to find habitat, food or mates on the other side.WASHINGTON STATE DEPT. OF TRANSPORTATION

    “Male fishers go on these huge walkabouts to find females,” Werntz says. While biologists assumed fishers would cross the freeway to search for mates, having photographic proof “is pretty wonderful,” he says.

    Happe and others hope to also see wildlife crossings along Interstate 5 one day. The freeway, which runs north-south near the coast, is the main obstacle keeping the Olympic and Cascade populations apart, she says. “We’re all working on wildlife travel corridors and connectivity in hopes the two populations hook up.”

    Learning curve

    The majority of the initial 90 fishers relocated to the Olympic Peninsula settled nicely into their new homes, according to radio tracking. In the year following release in that location, the fisher survival rate averaged 73 percent, but varied based on the year and season they were released, as well as sex and age of the fishers.

    Males fared better than females: Seventy-four percent of recorded deaths were of females, partly because they are smaller and more vulnerable to predators, such as bobcats and coyotes. Of 24 recovered carcasses where cause of death could be determined, 14 were killed by predators, seven were struck by vehicles, two drowned and one died in a leg-hold trap, Lewis, Happe and colleagues reported in the April 2022 Journal of Wildlife Management.

    Because the first fishers relocated to the Olympic Peninsula were released in several locations, the animals had trouble finding mates. As a result, only a few parents sired the subsequent generations.

    The researchers became concerned when they looked at the genetic diversity of fishers on the Olympic Peninsula six years post-relocation. Happe and colleagues set up 788 remote cameras and hair-snare stations: triangular cubbies open on either end with a chicken leg as bait in the middle and wire brushes protruding from either side to grab strands of fur. DNA analysis of the fur raised red flags about inbreeding, Happe and Lewis say.

    “Models showed we were going to lose up to 50 percent of genetic diversity, and the population would wink out in something like 100 years,” Happe says. To expand the gene pool, the team brought 20 more fishers to the Olympic Peninsula in 2021. These animals came from Alberta whereas the founding population had hailed from British Columbia.

    [embedded content]
    Two fishers from Canada are released from wooden crates, quickly disappearing into Olympic National Park in November 2021. Both wear radio tracking devices so that researchers can monitor their well-being.

    As the reintroduction effort moved into the Cascades, the team adapted, based on lessons learned from the Olympic Peninsula. For instance, to increase the likelihood of fishers finding each other more quickly, the animals were released at fewer sites that were closer together. The team also released the animals before January, giving females ample time to settle into a home range before the spring mating and birthing season.

    Finding their food

    As the experiment went on, more unanticipated findings popped up. Fishers released in the southern part of the Cascades were more likely to survive the first year (76 percent) than those relocated north of I-90 (40 percent), according to the final project report, released in June. Remote-camera data suggest that’s because there are less prey and slightly more predators in the North Cascades, says Tanner Humphries, community wildlife monitoring program lead for Conservation Northwest.

    And in both the Cascades and the Olympic Peninsula, fishers are using different types of habitat than biologists had predicted, Happe says. The mammals — once assumed to be old-growth specialists — are using a mosaic of young and old forests. Fishers require large, old trees with cavities for denning and resting. But in younger managed forests where trees are thinned or cut, prey may be easier to come by.

    Live traps in the South Cascades support that idea. Fishers’ preferred prey — snowshoe hares and mountain beavers — were most abundant in young regenerating forests. In older forests, traps detected mainly mice, voles and chipmunks, which are not substantial meals for fishers, Mitchell Parsons, a wildlife ecologist at Utah State University in Logan, reported with Lewis, Werntz and others in 2020 in Forest Ecology and Management.

    North America’s fisher populations are blossoming, helping to rebalance forest ecosystems.Emily Brouwer/NPS (CC BY 2.0)

    The future is re-wild

    After F023’s baby was caught on camera five years ago, the mother’s tracking chip degraded as designed — the hardware lasts less than two years. Since then, many more fisher kits have been born in Washington.

    In fact, these furry carnivores are one of the most successfully translocated mammals in North America. According to Lewis, 41 different translocation efforts across the continent have helped fisher populations blossom. The animals now occupy 68 percent of their historical range, up from 43 percent in the mid-1900s.

    With the last batch of fishers delivered to Washington in 2021, the relocation phase of the project has ended. Lewis, Happe and their partners plan to continue monitoring how these sleek tree-climbing carnivores are faring — and how the ecosystem is responding. For instance, fishers are indeed feasting on seedling-eating mountain beavers, according to research reported by Happe, Lewis and others in 2021 in Northwestern Naturalist.

    Given climate change, species loss and ecosystem degradation, animals worldwide face difficult challenges. The fact that fishers are thriving once again in Washington offers hope, Lewis says.

    “It’s a hard time, it’s a hard world, and this feels like something we’re doing right,” he says. “Instead of losing something, we’re getting it back.” More

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    Climate change could turn some blue lakes to green or brown

    Some picturesque blue lakes may not be so blue in the future, thanks to climate change.

    In the first global tally of lake color, researchers estimate that roughly one-third of Earth’s lakes are blue. But, should average summer air temperatures rise by a few degrees, some of those crystal waters could turn a murky green or brown, the team reports in the Sept. 28 Geophysical Research Letters.

    The changing hues could alter how people use those waters and offer clues about the stability of lake ecosystems. Lake color depends in part on what’s in the water, but factors such as water depth and surrounding land use also matter. Compared with blue lakes, green or brown lakes have more algae, sediment and organic matter, says Xiao Yang, a hydrologist at Southern Methodist University in Dallas.

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    Yang and colleagues used satellite photos from 2013 to 2020 to analyze the color of more than 85,000 lakes around the world. Because storms and seasons can temporarily affect a lake’s color, the researchers focused on the most frequent color observed for each lake over the seven-year period. The researchers also created an interactive online map that can be used to explore the colors of these lakes.

    The approach is “super cool,” says Dina Leech, an aquatic ecologist at Longwood University in Farmville, Va., who was not involved with the study. These satellite data are “just so powerful.”

    The scientists then looked at local climates during that time to see how they may be linked to lake color around the world. For many small or remote water bodies, records of temperature and precipitation don’t exist. Instead, the researchers also relied on climate “hindcasts” calculated for every spot on the globe, which are pieced together from relatively sparse records. 

    Lakes in places with average summer air temperatures that were below 19° Celsius were more likely to be blue than lakes with warmer summers, the researchers found. But up to 14 percent of the blue lakes they studied are near that threshold. If average summer temperatures increase another 3 degrees Celsius — an amount that scientists think is plausible by the end of the century — those 3,800 lakes could turn green or brown (SN: 8/9/21). That’s because warmer water helps algae bloom more, which changes the properties of the water, giving it a green-brown tint, Yang says.

    Extrapolating beyond this sample of lakes is a bit tricky. “We don’t even know how many lakes there are in the world,” says study coauthor Catherine O’Reilly, an aquatic ecologist at Illinois State University in Normal. Many lakes are too small to reliably detect via satellite, but by some estimates, tens of thousands of larger lakes could lose their blue hue.

    If some lakes do become less blue, people will probably lose some of the resources they have come to value, O’Reilly says. Lakes are often used for drinking water, food or recreation. If the water is more clogged with algae, it could be unappealing for play or more costly to clean for drinking.

    But the color changes wouldn’t necessarily mean that the lakes are any less healthy. “[Humans] don’t value lots of algae in a lake, but if you’re a certain type of fish species, you might be like ‘this is great,’” O’Reilly says.

    Lake color can hint at the stability of a lake’s ecosystem, with shifting shades indicating changing conditions for the critters living in the water. One benefit of the new study is that it gives scientists a baseline for assessing how climate change is affecting Earth’s freshwater resources. Continued monitoring of lakes could help scientists detect future changes.

    “[The study] sets a marker that we can compare future results to,” says Mike Pace, an aquatic ecologist at the University of Virginia in Charlottesville, who was not involved with the study. “That’s, to me, the great power of this study.” More

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    Gas flares are leaking five times as much methane than previously thought

    In many oil and gas producing regions, flames light the sky. The flares burn off 98 percent of the escaping natural gas, oil and gas companies claim. But observations of three U.S. oil and gas fields show efficiency is only around 91 percent, scientists report in the Sept. 30 Science. Making up the difference would be the equivalent of taking nearly 3 million cars off the road. 

    The natural gas escaping is primarily methane. This greenhouse gas lingers for only nine to 10 years in the atmosphere, but its warming potential is 80 times that of carbon dioxide. So oil and gas companies light flares — burning the methane to produce less-potent carbon dioxide and water. The industry and the U.S. government assumed those flares worked at 98 percent efficiency. But previous studies said that might be too optimistic, says Genevieve Plant, an atmospheric scientist at the University of Michigan in Ann Arbor (SN: 4/22/20).

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    Plant and her colleagues sent planes to sample air over more than 300 flares in the Bakken Basin in North Dakota and the Permian and Eagle Ford basins in Texas, which account for more than 80 percent of the flaring in the country. The samples showed five times as much methane unburned than previously estimated.

    The drop from 98 to 91 percent efficiency might seem small, but the effects are large, says Dan Cusworth, an atmospheric scientist at the University of Arizona in Tucson who was not involved in the study. “Any percentage that is in the methane phase instead of CO2 phase is substantially more problematic.”

    Half of the difference is due to flares that aren’t burning. “We expected that flares might show a range of efficiencies, but we did not expect to see so many unlit flares,” Plant says. Between 3 and 5 percent of flares weren’t working at all. If those fires were lit, and 98 percent efficiency achieved, the result could remove the equivalent of about 13 million metric tons of carbon from the atmosphere. Light ‘em up.  More

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    Jacky Austermann looks to the solid earth for clues to sea level rise

    It’s no revelation that sea levels are rising. Rising temperatures brought on by human-caused climate change are melting ice sheets and expanding ocean water. What’s happening inside Earth will also shape future shorelines. Jacky Austermann is trying to understand those inner dynamics.

    A geophysicist at Columbia University’s Lamont-Doherty Earth Observatory, Austermann didn’t always know she would end up studying climate. Her fascination with math from a young age coupled with her love of nature and the outdoors — she grew up hiking in the Alps — led her to study physics as an undergraduate, and later geophysics.

    As Austermann dug deeper into Earth’s geosystems, she learned just how much the movement of hot rock in the mantle influences life on the surface. “I got really interested in this entire interplay of the solid earth and the oceans and the climate,” she says.

    Big goal

    Much of Austermann’s work focuses on how that interplay influences changes in sea level. The global average sea level has risen more than 20 centimeters since 1880, and the yearly rise is increasing. But shifts in local sea level can vary, with those levels rising or falling along different shorelines, Austermann says, and the solid earth plays a role.

    “We think about sea level change generally as ‘ice is melting, so sea level is rising.’ But there’s a lot more nuance to it,” she says. “A lot of sea level change is driven by land motion.” 

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    Understanding that nuance could lead to more accurate climate models for predicting sea level rise in the future. Such work should help inform practical solutions for communities in at-risk coastal areas.

    So Austermann is building computer models that reconstruct sea level changes over the last few million years. Her models incorporate data on how the creeping churning of the mantle and other geologic phenomena have altered land and sea elevation, particularly during interglacial periods when Earth’s temperatures were a few degrees higher than they are today.

    Standout research

    Previous studies had suggested that this churning, known as mantle convection, sculpted Earth’s surface millions of years ago. “It pushes the surface up where hot material wells up,” Austermann says. “And it also drags [the surface] down where cold material sinks back into the mantle.”

    In 2015, Austermann and colleagues were the first to show that mantle-induced topographic changes influenced the melting of Antarctic ice over the last 3 million years. Near the ice sheet’s edges, ice retreated more quickly in areas where the land surface was lower due to convection.

    What’s more, mantle convection is affecting land surfaces even on relatively short time scales. Since the last interglacial period, around 130,000 to 115,000 years ago, mantle convection has warped ancient shorelines by as much as several meters, her team reported in Science Advances in 2017.  

    Jacky Austermann builds computer models that reconstruct sea level changes over the last few million years. The work could improve models that forecast the future.Bill Menke

    The growing and melting of ice sheets can deform the solid earth too, Austermann says. As land sinks under the weight of accumulating ice, local sea levels rise. And as land uplifts where the ice melts, water falls. This effect, as well as how the ice sheet tugs on the water around it, is shifting local sea levels around the globe today, she says, making it very relevant to coastal areas planning their defenses in the current climate crisis.

    Understanding these geologic processes can help improve models of past sea level rise. Austermann’s team is gathering more data from the field, scouring the coasts of Caribbean islands for clues to what areas were once near or below sea level. Such clues include fossilized corals and water ripples etched in stone, as well as tiny chutes in rocks that indicate air bubbles once rose through sand on ancient beaches. The work is “really fun,” Austermann says. “It’s essentially like a scavenger hunt.”

    Her efforts put the solid earth at the forefront of the study of sea level changes, says Douglas Wiens, a seismologist at Washington University in St. Louis. Before, “a lot of those factors were kind of ignored.” What’s most remarkable is her ability “to span what we normally consider to be several different disciplines and bring them together to solve the sea level problem,” he says.

    Building community

    Austermann says the most enjoyable part of her job is working with her students and postdocs. More than writing the next big paper, she wants to cultivate a happy, healthy and motivated research group. “It’s really rewarding to see them grow academically, scientifically, come up with their own ideas … and also help each other out.”

    Roger Creel, a Ph.D. student in Austermann’s group and the first to join her lab, treasures Austermann’s mentorship. She offers realistic, clear and fluid expectations, gives prompt and thoughtful feedback and meets for regular check-ins, he says. “Sometimes I think of it like water-skiing, and Jacky’s the boat.”

    For Oana Dumitru, a postdoc in the group, one aspect of that valued mentorship came in the form of a gentle push to write and submit a grant proposal on her own. “I thought I was not ready for it, but she was like, you’ve got to try,” Dumitru says.

    Austermann prioritizes her group’s well-being, which fosters collaboration, Creel and Dumitru say. That sense of inclusion, support and community “is the groundwork for having an environment where great ideas can blossom,” Austermann says.

    Want to nominate someone for the next SN 10 list? Send their name, affiliation and a few sentences about them and their work to sn10@sciencenews.org. More

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    ‘Fen, Bog & Swamp’ reminds readers why peatlands matter

    Fen, Bog & SwampAnnie ProulxSimon & Schuster, $26.99

    A recent TV ad features three guys lost in the woods, debating whether they should’ve taken a turn at a pond, which one guy argues is a marsh. “Let’s not pretend you know what a marsh is,” the other snaps. “Could be a bog,” offers the third.

    It’s an exchange that probably wouldn’t surprise novelist Annie Proulx. While the various types of peatlands — wetlands rich in partially decayed material called peat — do blend together, I can’t help but think, after reading her latest book, that a historical distaste and underappreciation of wetlands in Western society has led to the average person’s confusion over basic peatland vocabulary.

    In Fen, Bog & Swamp: A Short History of Peatland Destruction and Its Role in the Climate Crisis, Proulx seeks to fill the gaps. She details three types of peatland: fens, which are fed by streams and rivers; bogs, fed by rainwater; and swamps, distinguishable by their trees and shrubs. While all three ecosystems are found around most of the world, Proulx focuses primarily on northwestern Europe and North America, where the last few centuries of modern agriculture led to a huge demand for dry land. Wet, muddy and smelly, wetlands were a nightmare for farmers and would-be developers. Since the 1600s, U.S. settlers have drained more than half of the country’s wetlands; just 1 percent of British fens remains today.

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    Only recently have the consequences of these losses become clear. “We are now in the embarrassing position of having to relearn the importance of these strange places,” Proulx writes. For one, peatlands have great ecological value, supporting a variety of wildlife. They also sequester huge amounts of carbon dioxide, and some peatlands prevent shoreline erosion, while buffering land from storm surges (SN: 3/17/18, p. 20). But the book doesn’t spend too much time on nitty-gritty ecology. Instead, Proulx investigates these environments in the context of their relationship with people.

    Known for her fiction, Proulx, who penned The Shipping News and “Brokeback Mountain,” draws on historical accounts, literature and archaeological digs to imagine places lost to time. She challenges the notion that wetlands are purely unpleasant or disturbing — think Shrek’s swamp, where only an ogre would want to live, or the Swamps of Sadness in The Neverending Story that swallow up Atreyu’s horse.

    Proulx jumps back as far as 20,000 years ago to the bottom of the North Sea, which at the time was a hilly swath called Doggerland. When sea levels rose in the seventh century B.C., people there learned to thrive on the region’s developing fens, hunting for fish and eels. In Ireland, “bog bodies” — many thought to be human sacrifices — have been preserved in the peat for thousands of years; Proulx imagines torchlit ceremonies where people were offered to the mud, a connection to the natural world that is hard for many people to comprehend today. These spaces were integrated into the local cultures, from Renaissance paintings of wetlands to British lingo such as didder (the way a bog quivers when stepped on). Proulx also reflects on her own childhood memories — wandering through wetlands in Connecticut, a swamp in Vermont — and describes how she, like writer Henry David Thoreau, finds beauty in these places. “It is … possible to love a swamp,” she says.

    Fens, bogs and swamps are technically distinct, but they’re also fluid; one wetland may transition into another depending on its water source. This same fluidity is reflected in the book, where Proulx flits from one wetland to another, from one part of the world to another, from one millennium to another. At times didactic and meandering, Proulx will veer off to discuss humankind’s destructive tendency not just in wetlands, but nature in general, broadly rehashing aspects of the climate crisis that most readers interested in the environment are probably already familiar with. I was most enthralled — and heartbroken — by the stories I had never heard before: of “Yde Girl,” a redheaded teenager sacrificed to a bog; the zombie fires in Arctic peatlands that burn underground; and the ivory-billed woodpecker, a bird missing from southern U.S. swamps for almost a century.

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