How Hot Can Antarctica Get?

Home , Copley (crater), Earthling (Fringe), Kinabatangan River, Signy Research Station

VOL. 98 NO. 5 MAY 2017 Seaﬂ oor in the MH370 Search Area

What Is Snow Drought?

Earth & Space Science News Earth’s Deep Carbon

HOW HOT CAN ANTARCTICA GET?

Earth & Space Science News Contents

MAY 2017 PROJECT UPDATE VOLUME 98, ISSUE 5

Geological Insights from the Search for Malaysia Airlines Flight MH370 A rich trove of marine geophysical data acquired in the search for missing flight MH370 is yielding knowledge of ocean floor processes at a level of detail rare in the deep ocean.

PROJECT UPDATE

Synthesizing Our Understanding of Earth’s Deep Carbon The Deep Carbon Observatory is entering a new phase, in which it will integrate 10 years of discoveries into an overarching model to benefit the scientific community 18 and a wider public.

OPINION COVER Defining Snow Drought Evaluating the Highest Temperature 15and Why It Matters Swings from snow drought to extreme Extremes in the Antarctic winter rainfall make managing reservoirs The record high temperature for regions south of 60°S latitude is a balmy 19.8°C incredibly difficult. But what exactly is (67.6°F), recorded 30 January 1982 at a research station on Signy Island. “snow drought”?

Earth & Space Science News Eos.org // 1 Contents

DEPARTMENTS

Editor in Chief Barbara T. Richman: AGU, Washington, D. C., USA; eos_ [email protected] Editors Christina M. S. Cohen Wendy S. Gordon Carol A. Stein California Institute Ecologia Consulting, Department of Earth and of Technology, Pasadena, Austin, Texas, USA; Environmental Sciences, Calif., USA; wendy@ecologiaconsulting University of Illinois at [email protected] .com Chicago, Chicago, Ill., José D. Fuentes David Halpern USA; [email protected] Department of Meteorology, Jet Propulsion Laboratory, Pennsylvania State Pasadena, Calif., USA; University, University davidhalpern29@gmail Park, Pa., USA; .com [email protected] Editorial Advisory Board Nathan T. Bridges, Planetary Sciences John W. Lane, Near-Surface Geophysics Mark G. Flanner, Atmospheric Sciences Jian Lin, Tectonophysics 43 Nicola J. Fox, Space Physics Figen Mekik, Paleoceanography and Aeronomy and Paleoclimatology Peter Fox, Earth and Space Science Jerry L. Miller, Ocean Sciences Informatics Thomas H. Painter, Cryosphere 34–39 AGU News Steve Frolking, Biogeosciences Sciences Edward J. Garnero, Study of the Philip J. Rasch, Global Environmental Getting to Fair: Recognizing Implicit Earth’s Deep Interior Change Bias and Easing Its Impact; Radio Michael N. Gooseff, Hydrology Eric M. Riggs, Education Brian C. Gunter, Geodesy Adrian Tuck, Nonlinear Geophysics Science and Space Weather Now Kristine C. Harper, History Sergio Vinciguerra, Mineral Available on IEEE Xplore; Outstanding of Geophysics and Rock Physics Student Paper Awards. Susan E. Hough, Natural Hazards Andrew C. Wilcox, Earth and Planetary Emily R. Johnson, Volcanology, Surface Processes Geochemistry, and Petrology Earle Williams, Atmospheric Keith D. Koper, Seismology and Space Electricity 40–43 Research Spotlight Robert E. Kopp, Geomagnetism Mary Lou Zoback, Societal Impacts and Paleomagnetism and Policy Sciences Polar Interlopers in the Aurora; After Decades, High-Altitude Staff Observations Revived at Jicamarca; Production and Design: Faith A. Ishii, Production Manager; Melissa A. Tribur, Senior 7 Production Specialist; Elizabeth Jacobsen, Production and Editorial Assistant; Karen River’s Rise Linked to Oklahoma’s Lomax, Acting Manager, Design and Branding; Travis Frazier and Valerie Friedman, Largest Earthquake; What Electronic Graphics Specialists Proportion of River Nutrients Editorial: Peter L. Weiss, Manager/Senior News Editor; Mohi Kumar, Scientific 3–9 News Content Editor; Randy Showstack, Senior News Writer; JoAnna Wendel, News Writer; Reaches the Open Sea?; Radar Liz Castenson, Editorial and Production Coordinator Lunar Lava Tubes Could Offer Method Shows Promise in Aquifer; Marketing: Jamie R. Liu, Manager, Marketing; Angelo Bouselli and Tyjen Conley, Future Moon Explorers a Safe When Income Goes Up, Does Marketing Program Managers Haven; Study Finds That Coastal Pollution Go Down? Advertising: Tracy LaMondue, Director, Development; Tel: +1-202-777-7372; Email: [email protected] Wetlands Excel at Storing Carbon; Scientists Witness Glacial Outburst ©2017. American Geophysical Union. All Rights Reserved. Material in this issue may 44–48 Positions Available be photocopied by individual scientists for research or classroom use. Permission is Flood Near Mount Everest; Images also granted to use short quotes, figures, and tables for publication in scientific books of Pan, Saturn’s Ravioli Moon, in Current job openings in the Earth and journals. For permission for any other uses, contact the AGU Publications Office. Unprecedented Detail; Kilimanjaro’s and space sciences. Eos (ISSN 0096-3941) is published monthly by the American Geophysical Union, 2000 Florida Ave., NW, Washington, DC 20009, USA. Periodical Class postage paid Iconic Snows Mapped in Three at Washington, D. C., and at additional mailing offices. POSTMASTER: Send address Dimensions. Inside Back Cover: changes to Member Service Center, 2000 Florida Ave., NW, Washington, DC 20009, USA. Postcards from the Field Member Service Center: 8:00 a.m.–6:00 p.m. Eastern time; Tel: +1-202-462-6900; 10–11 Meeting Report Explorers descend into an ice cave Fax: +1-202-328-0566; Tel. orders in U.S.: 1-800-966-2481; Email: service@ agu.org. Cities Smarten Up and Go Green; on Antarctica’s Mount Erebus. Use AGU’s Geophysical Electronic Manuscript Submissions system to submit Using Archives of Past Floods to a manuscript: http://eos-submit.agu.org. Estimate Future Flood Hazards. On the Cover Views expressed in this publication do not necessarily reflect official positions of the American Icicles hang from a melting iceberg Geophysical Union unless expressly stated. 12–17 Opinion near Petermann Island, off the Christine W. McEntee, Executive Director/CEO Airline Flight Paths over the Antarctic Peninsula. Credit: Danita Unmapped Ocean; Defining Snow Delimont/Gallo Images/Getty Drought and Why It Matters. Images.

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orbiter SELENE (Selenological and Engineering Lunar Lava Tubes Could Offer Explorer), also known as Kaguya. What the researchers didn’t know was whether the pit Future Moon Explorers a Safe Haven led to something larger below. Two narrow surface depressions called sinuous rilles, which scientists think represent collapsed portions of lava tubes, stretch away from the unar colonization isn’t mere science fic- flows, with basalt sometimes running as pit. Could the pit be a skylight opening to an tion anymore. Billionaires plan to send molten rivers. In these rivers, the outside intact lava tube’s long, narrow passage? L tourists on once- in- a- lifetime trips, and cools faster than the inside, creating a hard Ancient basaltic lava flows called maria politicians say that they hope to colonize the shell. The remaining lava pours out, leaving a cover much of the Moon, similar to the much Moon in the next few decades. There may even hollow space behind. younger Columbia River basalts in the western be ways for human colonists to harvest water Do similar lava tubes exist on the Moon? United States. Because the Moon’s gravity is from ice that may be permanently shadowed In a presentation on 22 March at the one sixth that of Earth’s, gravity doesn’t in certain caves. 48th Lunar and Planetary Science Conference But where could a human colony actually (LPSC) in The Woodlands, Texas, Junichi live? The Moon has no atmosphere or mag- Haruyama, a senior researcher at the Japan If humans ever got access netic field to shield it from solar radiation, Aerospace Exploration Agency (JAXA), dis- to the tubes, “the science and micrometeorites constantly rain onto its cussed one such lava tube that he suspects surface. That’s no environment for our may be snaking underneath the Moon’s sur- would be amazing.” squishy, earthling bodies. face. Scientists studying the Moon’s surface may have found the answer: Humans could shelter Searching for Lava Tubes in lunar lava tubes. The Moon is covered in In 2009, Haruyama and his team spotted evi- impede lava flow as much, allowing lava to huge swaths of ancient basaltic lava flows. dence of a dark hole in the Moon’s Marius spread widely across the surface. Nonetheless, Earth’s volcanoes can also erupt in similar Hills region in data from the Japanese lunar lunar lava tubes may have formed in an Earth- like way, Haruyama said. Last year, another team spotted gravity anomalies that suggested hollow, narrow spaces around the Marius Hills pit. These data came from NASA’s Gravity Recovery and Inte- rior Laboratory (GRAIL) mission, which con- sists of two spacecraft orbiting the Moon. The orbiters can detect these anomalies by measuring how much the Moon’s gravity tugs on them. Areas of more mass tug on the spacecraft more, whereas hollow areas have less mass and so tug on GRAIL less. To confirm GRAIL’s findings, Haruyama and his colleagues turned again to SELENE’s data, looking closer at the sinuous rilles. They spe- cifically looked at data from SELENE’s Lunar Radar Sounder (LRS), which imaged the subsurface using low- frequency radio waves. The LRS data revealed hollow space more than 100 meters deep in some places and tens of kilometers long underneath one of the rilles near the pit. The pit itself looked to be 50 meters deep. These data led researchers to believe that the pit could, indeed, be a collapsed portion of a lava tube roof. These data also match the gravity readings from GRAIL, Haruyama said.

Exploring the Tubes If humans, via rover or their own two feet, ever got access to the tubes, “the science would be amazing,” said Brent Garry, a geo- physicist at NASA Goddard Space Flight Cen-

NASA/GSFC/Arizona State University State NASA/GSFC/Arizona ter. The tube’s interior tempts with pristine The Marius Hills pit on the Moon, spotted in 2009 by scientists at the Japan Aerospace Exploration Agency. The pit surfaces, absent of lunar soil or bombardment stretches 65 meters across and could be a skylight leading down to a lava tube, the scientists say. by micrometeorites, he said. These surfaces

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could offer answers to questions about the Moon’s origin and formation. Study Finds That Coastal Wetlands In another LPSC presentation on 22 March, Garry described a way to closely explore these Excel at Storing Carbon tubes, using lidar. On Earth, scientists use lidar scanners to map both land and the ocean floor. More recently, they have started using lidar to map Earth’s many cave systems. Over the past 2 years, Garry and his team used a lidar scanner to map the inside of a lava tube at Craters of the Moon National Monument and Preserve in Idaho. The park is named for the otherworldly feel of its basaltic lava flows. Apollo astronauts even studied the geology of the park before ever stepping on its namesake. Lidar scanners work by pinging their sur- roundings with beams of laser light and measuring the time it takes for the light to bounce back. The scanners can take millions of data points every second, allowing for the creation of highly detailed 3-D maps. They also don’t depend on sunlight, which could make them useful in a shadowy lunar pit. Garry suggests that lidar would be extremely useful in mapping centimeter- to millimeter- scale features, helping future explorers determine the structure of a lava tube. How to get the scanner into a tube is another story, one that would involve trans- portation using a rover, Garry said.

Future of Lunar Exploration Bethany Augliere Haruyama and Garry agree that lava tubes Mangroves currently cover 14–15 million hectares around the world but are steadily disappearing. These coastal for- could, in theory, shield humans from the ests trap an estimated 31–34 billion kilograms of carbon every year, making them carbon storage powerhouses. Sun’s unfiltered radiation and the wide surface temperature fluctuations experienced on the Moon: Temperatures over 1 Moon day s humans continually add carbon diox- sequester carbon. There are many solutions, (27 Earth days) can range between 123°C and ide to the atmosphere, getting rid of but deciding which is most effective—oceans, −153°C. In contrast, Earth’s average tempera- A the excess greenhouse gas has become forests, mangroves, or kelp farming, for ture is only about 16°C. a priority. Scientists are searching for new example—can be daunting. In addition, many What’s more, lunar lava tubes likely have ways to remove carbon from the atmosphere studies use different timescales or measure- flat floors like those on Earth, easing the way and put it into long-term lockdown. ments, further muddying carbon storage com- for vehicles or instruments, Haruyama said. The ocean’s ability to soak up carbon like a parisons. However, long-term human colonies on sponge is well known, but researchers are now “The goal of the paper was to try and com- the Moon likely won’t happen in the near— taking a fresh look at ocean shores. Our planet pare apples to apples,” said Jennifer Howard, or even far—future. Ben Bussey, chief explo- has about 620,000 kilometers of coastline, lead author of the paper and marine climate ration scientist for the Human Exploration long enough to wrap around Earth about change director at Conservation International and Operations Mission Directorate at NASA, 15 times. in Arlington, Va. On 1 February, she and her explained during a NASA town hall meeting In a recent paper in Frontiers in Ecology and colleagues published their detailed report at LPSC that NASA’s deep-space habitability the Environment (http:// bit . ly/ Environ2017), online, which compares carbon storage by plans are currently focused on reaching Mars researchers analyzed multiple ways in which coastal blue carbon ecosystems with storage and that “plans don’t call for going onto the nature captures carbon in marine ecosystems, by algae and marine animals. lunar surface before going to Mars.” a reservoir known as blue carbon. They found But if those plans ever change, at least we that coastal mangroves, seagrasses, and tidal Carbon Storage Powerhouses know we might have a place to crash—figu- marshes, or coastal blue carbon, provided par- Plants take carbon out of the atmosphere, ratively, at least. ticularly effective and long-lasting carbon storing it in leaves, roots, and branches. On storage. land, when vegetation falls to the ground, the The 2015 Paris Agreement has intensified bits break down quickly, releasing carbon back By JoAnna Wendel (@JoAnnaScience), Staff pressure on nations that signed the pact to into the atmosphere. Not so in coastal wet- Writer meet carbon goals and find better ways to lands. There, Howard explained, tidally driven

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salt water saturates soil twice a day in mangrove forests and tidal marshes and continuously in sea- grass ecosystems, which are per- petually submerged. Saltwater inundation inhibits the microbial breakdown of plant debris, trap- ping it in the soil. The authors note that 50% to 90% of coastal blue carbon storage occurs in the soil, not the plants. “You can still see intact leaves 3 meters down,” Howard said. “The carbon is stable.”

Vegetation trapped in coastal 0) blue carbon soils can be meters ccby2- thick and hundreds of years old. By contrast, kelp, which also grows in coastal forests, lacks the extensive root systems that collect debris and sediment that become carbon- rich soils typical of coastal wetlands. Living kelp plants trap carbon for only a short time because of their relatively (http://bit.ly/ 2.0 Jack Flanagan, CC BY short life spans. A tidal marsh on the East Coast of the United States. Recent research found that mangrove forests, seagrasses, and salt marshes like Howard said that kelp and other this one, which are the three main types of coastal blue carbon ecosystems, trap and store carbon more effectively than other marine organisms that trap carbon— ecosystems. phytoplankton, corals, and fish— are always discussed at international meetings. She and her colleagues often identified using remote sensing, which According to the Blue Carbon Initiative, a scoured recent research on the abilities of takes satellite scans of Earth and divides the global program focused currently on coastal those organisms and coastal wetlands to hold surface into pixelated blocks. In those images, ecosystems as a bulwark against climate carbon. They consolidated the findings and “it’s very hard to distinguish a marsh from a change, 50% of the world’s mangrove forests used the same units of measurement and field and sometimes even bare ground,” said have vanished over the past 50 years. The timescales to compare coastal blue carbon to Megonigal. “It’s partly a matter of [needing] mangrove disappearance allows the trapped, other ecosystems like phytoplankton and higher- resolution data,” he said. thick, blue carbon soils to be washed away, kelp. Howard notes that although all ocean releasing carbon back into the system. It also ecosystems are important, coastal blue carbon Fifty percent of the eliminates storm buffering, leaving communi- is the standout, not only in how long it can ties much more vulnerable to harsh weather. retain carbon but also in how much it can trap. world’s mangrove forests Managing and restoring mangroves helps off- set carbon emissions while providing valuable Manageable Natural Storage have vanished over the habitat, ecosystem health, and land conserva- The study confirms that “these [coastal blue past 50 years. tion. carbon systems] are hot spots for carbon stor- Coastal blue carbon systems are also adapt- age,” said Patrick Megonigal, associate direc- able to sea level fluctuations, as long as the tor of research at the Smithsonian Environ- changes aren’t too fast. “They can build mental Research Center in Edgewater, Md.; he Mapping by remote sensing is next to themselves up over time, increasing soil was not an author of the study. In addition, impossible for seagrasses because they live height,” said Howard. those coastal ecosystems have the ability to be underwater. “Most people would be surprised Howard noted that 150 countries that signed managed to preserve and extend their bound- that we don’t know where they are,” said on to the Paris Agreement have coastal wet- aries and therefore their impact on carbon Howard. “We rely on awesome remote sens- lands, but only 29 are currently talking about emissions, Megonigal noted. How readily eco- ing, but it only gets you so far with water” in coastal mitigation. Now that the new study is systems respond to human management the way. out, she hopes it will awaken greater interest strongly affects their value in climate mitiga- in that option. “If countries knew how big a tion, he said. Blue Carbon Benefits sink [coastal blue carbon] is,” Howard said, The study found that annually, coastal The researchers noted that nations counter- “they might be excited.” mangroves, tidal marshes, and seagrasses balancing their emissions by fostering coastal each trap and store 2 to 35 times more carbon blue carbon ecosystems could also get other than ocean phytoplankton. The large range benefits. These ecosystems help strengthen By Sarah Derouin (email: sarah . derouin@ gmail results from the challenges in mapping these biodiversity, tourism, fisheries, and storm .com), Science Communication Program Graduate ecosystems. Coastal blue carbon areas are protection. Student, University of California, Santa Cruz

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14 June, the researchers returned to Lhotse Scientists Witness Glacial Outburst Glacier to do fieldwork and reconstruct the path of the floodwater. Flood Near Mount Everest The scientists measured and photo- graphed the terrain and found sinkholes, ponds, uprooted alpine shrubs, and wet sediments, all signs of recent flooding. They awareness of glacial lake outburst also examined satellite imagery of Lhotse floods, a perennial danger for Glacier taken in May and noted 274 ponds those downstream of Imja Lake atop the ice. By measuring the ponds’ areas and its notoriously unstable in the images and using a known relation moraine dam. On the morning of between pond area and volume, the scien- 12 June, some of the scientists tists were able to estimate the total volume were doing fieldwork near Lhotse of all of the visible bodies of water. Glacier, an avalanche- fed glacier Assuming that all of the ponds had that originates at the peak of Lho- drained completely, their total volume tse, the fourth- highest mountain would be only about 20% of the estimated in the world. flood volume, the researchers calculated. Byers remembers hearing what Thus, “a significant amount of the floodwa- sounded like a rockfall. She then ter was stored in the glacier’s subsurface,” saw a “black tongue of water, the authors wrote. boulders, and silt” racing downhill toward the village of Ice like Swiss Cheese Bidhya Sharma Chukhung. She grabbed her cam- Within a glacier, water travels in conduits, A glacial outburst flood from Lhotse Glacier on 12 June 2016 threatens a era and shot the video. which can be as large as several meters across. stone wall adjacent to the village of Chukhung, Nepal. “I have never experienced such Swiss cheese is “a very good analogy” to adrenaline,” Byers said. “I felt explain a glacier’s interior structure, said powerless to help people…and at David Rounce, a glaciologist at the University he black water, heavy with debris, came the same time experienced utter fascination at of Texas at Austin and a member of the tumbling apparently out of nowhere, the geologic process unfolding before my research team. T gushing over the rocky terrain and eyes.” Sometimes those conduits can become pushing boulders around like toys. The glacial outburst flood that Byers and blocked by ice or debris such as sand and boul- This torrent, known as a glacial outburst her colleagues witnessed slowly subsided over ders. When sufficient water pressure builds up flood, forms when water stored deep within a the next hour. But the trail below the behind the natural dam to cause it to burst, glacier is released without warning. A team of researchers had been washed away, and the the torrent that’s released can be substantial, scientists witnessed this rare event firsthand only route to Chukhung was over the glacier like the flooding that the team observed in as one spilled down the Lhotse Glacier near itself, crossing an ice bridge with water still June. Mount Everest on 12 June 2016. moving rapidly below it, Byers recalled. “These floods are particularly difficult to Their view, captured on video, affords The scientists hurried over the ice bridge prepare for because there is often no visual researchers and the public an up close look at and down into Chukhung. They found that all evidence of their threat,” said Duncan the mechanics of a glacial outburst flood. “All of the villagers were accounted for and that Quincey, a glaciologist at the University of of our studying was suddenly brought into the community had lost only one outhouse. Leeds who reviewed the paper. focus, and revised, as we witnessed this The large rock wall that the community had No one can predict when another glacial event,” said Elizabeth Byers, a hydrologist at built 1 year earlier—using donations from the outburst flood might strike, but team mem- the consulting firm Appalachian Ecology in scientists after Nepal’s devastating 2015 bers will have their cameras ready on future West Virginia and a member of the team. The earthquake—had held. “It was twisted in field campaigns. “It’s possible that we’ll wit- team published its scientific findings and some places but was enough to keep the ness another one,” said Rounce. video in a communication brief in February in floodwaters from destroying the village,” said The Cryosphere (http:// bit . ly/ CryoGOF2017). Byers. “Glacial outburst floods are widespread, but The scientists later estimated that more By Katherine Kornei (email: hobbies4kk@ gmail observations of them are rare, especially by than 2 million cubic meters of water—enough .com; @katherinekornei), Freelance Science Jour- scientists,” said Mark Carey, a glacier to fill the Empire State Building twice—had nalist researcher at the University of Oregon not been released in the flood. involved in the study. “This firsthand assessment illuminates more details about how Hidden Deep Within floods work.” Although the scientists were in Nepal to To see a video of the glacial better understand floods from glacial lakes, outburst flood at Lhotse Racing Downhill the glacial outburst flood—in which the In 2016, a team of American researchers was water spilled not from a lake but from within Glacier, visit http://bit.ly/ working in Nepal near Imja Lake, one of the the glacier itself—provided them with an Eos_Flood. region’s largest glacial lakes. They were col- important opportunity to examine flow pat- laborating with local communities to improve terns from sudden events. Beginning on

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Images of Pan, Saturn’s Ravioli Moon, in Unprecedented Detail

the imaging science team for Cassini and current visiting scholar at the University of California, Berkeley, told Eos. Throughout its orbit around Saturn’s poles, Cassini passes Saturn’s equator and is now “just skimming the outer portion of the rings,” she continued. This close orbit allows the spacecraft to take close-up pictures of moons like Pan, which orbits Saturn at a distance of 134,000 kilometers. The new images of the 35-kilometer-wide moon feature a resolution as fine as 150 meters. NASA/JPL-Caltech/Space Science Institute NASA/JPL-Caltech/Space “It’s just startling. The (Left) A newly released raw image of Pan, one of Saturn’s innermost moons, showing a polar view. (right) Another raw image of Saturn’s detail is startling,” Porco said moon Pan, with its bulging equator at an angle. The ridge is material along Pan’s equator. The new, detailed images have a resolution of of the new images. 150 meters; Pan itself is 35 kilometers wide. Scientists have known about Pan’s tutu-shaped waistline for a long time. Ten t’s a flying saucer! No, a celestial Saturn’s tiny moon Pan and its equatorial years ago, Porco and her team published two empanada! Or space ravioli? Nope—the fringe in unprecedented detail. papers describing how the bulge could have I weird raw images released by NASA’s Jet The Cassini spacecraft, which has been formed. From computer models, the Propulsion Laboratory on 9 March feature orbiting Saturn since 2004, will crash into Sat- researchers suspect that as the moon urn later this year. coalesced, material from Saturn’s rings fell But its final descent onto the tiny moon’s equator and built up its brings the spacecraft disklike silhouette. closer than ever to Over millions of years, Pan blazed a trail Saturn’s rings and through Saturn’s A ring, clearing what’s now offers scientists a known as the Encke Gap. The influx of material wealth of new onto Pan’s equator has decreased but likely research opportuni- continues to some degree to this day, which is ties. why the bulging belt itself looks smoother than This is because the the rest of the moon, Porco noted. spacecraft has “Aside from just the sheer joy of seeing entered its “ring something so alien at such a level of detail,” grazing orbits,” Car- the images will be helpful to scientists olyn Porco, leader of studying small moons, asteroids, or comets, Porco continued. Studying Pan will be particularly helpful when scientists think about Can you spot Pan? It’s how material builds up on a small body that the tiny, bright dot in the has very weak gravity. middle of the Encke Gap, So images like these have “an extension in Saturn’s A ring. For beyond the Saturn system,” she said. millions of years, Pan has You can see more raw images of Pan at been gathering material http://bit.ly/SaturnRaw2017. onto its surface and kick- ing material out of its way to form the 325- By JoAnna Wendel (@JoAnnaScience), Staff

NASA/JPL-Caltech/Space Science Institute NASA/JPL-Caltech/Space kilometer- wide gap. Writer

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batteries, solar panels and chargers, and lap- Kilimanjaro’s Iconic Snows tops. After 6 days of climbing through progres- Mapped in Three Dimensions sively thinner air and sleeping in tents each night, the group reached the broad slope of Kilimanjaro’s summit and set up camp near one edge of the Northern Ice Field, the largest n 1936, Ernest Hemingway described the top sions could enhance scientists’ understanding remaining ice field atop Kilimanjaro. Bohleber of Kilimanjaro as being “as wide as all the of how the remaining ice fields are changing, brushes off the difficulties he and his col- I world, great, high, and unbelievably white Bohleber said. leagues encountered, which included unex- in the sun.” However, the mountain’s ice cap pected delays and altitude sickness. “You’re so has been shrinking in recent decades because Carried Up, Up, Up focused on work up there that you hardly of warming temperatures, and only fragments Although researchers regularly use ground- think about anything else,” he said. of it remain today. penetrating radar to peer inside glaciers, “it’s In new observations of those fragments, never really been done on Kilimanjaro,” A Peek Inside researchers have revealed the thickness and Bohleber told Eos. That’s largely because of Ground- penetrating radar emits radio waves volume of Kilimanjaro’s largest remaining ice Kilimanjaro’s relative isolation, he explained. that travel down through the ice, bounce off field with ground- penetrating radar. Several “In the Alps, we can fly the equipment in internal structures or the bed of loose, silty previous studies documenting the retreat of [using a helicopter].” But finding a helicopter sand below, and return to the receiver. Using Kilimanjaro’s ice used aerial imaging that and pilot able to fly above 5000 meters in the known speed of radio waves through gla- showed changes in only two dimensions. eastern Tanzania isn’t easy, he said, so cial ice, researchers can then calculate the Using ground- penetrating radar, “you basi- “everything has to be carried on the back of a depths at which those reflections occurred and cally see straight down into the glacier,” said porter up the mountain.” map out the size and shape of the glacier. physicist Pascal Bohleber of the Institute for In September 2015, after receiving funding Over the course of 3 days, Bohleber and his Interdisciplinary Mountain Research of the from the National Geographic Global Explo- colleagues obtained thousands of measure- Austrian Academy of Sciences in Innsbruck, ration Fund, Bohleber and four other scien- ments while dragging their radar equipment who led the team that brought ground- tists met at Kilimanjaro International Air- over the surface of the Northern Ice Field. The penetrating radar to Kilimanjaro’s nearly 6000 port. They drove to Kilimanjaro National Park team then calculated the depth of the bed meter high summit for the first time. “It’s like and then hiked the Umbwe trail up the below the ice at many different locations and an X- ray of the glacier.” mountain’s flanks. Roughly 45 porters extrapolated the data to create a map of ice In addition to providing a new perspective accompanied the scientists, carrying the depth. They found that the ice ranged in on the vanishing ice, periodic radar measure- group’s equipment, which included ground- thickness from roughly 6 to 54 meters, with ments of the mountain’s ice in three dimen- penetrating radar antennas and receivers, the thickest section running along a ridge oriented roughly east–west, the researchers reported on 9 Febru- ary in The Cryosphere (http:// bit . ly/ Cryo2017). The team confirmed the accuracy of their ground- penetrating radar measurements using a simple, low- tech test: They showed that the depth calculated along ice cliffs at one edge of the ice field was consistent with the depth measured by hanging a rope off the same edge.

Tracking the Loss “This study provides a strong complement to previous airborne, satellite, modeling, and ice core studies of the Kilimanjaro ice fields,” said Kimberly Casey, a glaciologist affiliated with NASA Goddard Space Flight Center and the U.S. Geological Survey who was not involved in the study. In fact, by comparing their new map of ice depth with data from ice cores sampled by other

iStock.com/MHGALLERY researchers in 2000, Bohleber and Mount Kilimanjaro. his colleagues found that the ice

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the total ice volume improvement over previous studies, which of the Northern Ice simply assumed that the bed was flat, he Field to be roughly explained. 12 million cubic The team also demonstrated that the lay- meters. That’s ering of ice within the Northern Ice Field was enough ice to fill all very regular and horizontal. “At least for the of Manhattan’s Cen- upper 30 meters in the central plateau area, tral Park to a depth it’s like a layered cake,” said Bohleber. That of 4 meters. This discovery means that ice samples from the volume estimate is Northern Ice Field’s exposed walls are repre- useful for monitor- sentative of its interior, good news for scien- ing ice loss, said tists who are studying the ice structure from Bohleber. the outside. Bohleber and his colleagues are looking for- An Edge Below ward to using their methods to trace the evo- the Ice lution of the Northern Ice Field in three

Doug Hardy, UMass Geosciences Doug Hardy, Besides shedding dimensions. He said his team hopes to take This cliff face along an edge of Mount Kilimanjaro’s Northern Ice Field reveals orderly light on the depth of measurements on the summit again in a cou- horizontal layering of the glacier’s ice Kilimanjaro’s ice, ple of years to create a new three-dimensional the new measure- map. Comparing it with the current one would ments also revealed help the researchers track the rate of ice loss field had fallen in height by an average of the topography of the underlying sandy bed. in detail, he explained. 6 meters over 15 years. Other glaciers at lower Kilimanjaro is a dormant volcano, and the elevations on Kilimanjaro have decreased in team detected an edge of one of its crater height even more substantially, said Bohleber. rims below the ice. By Katherine Kornei (email: hobbies4kk@ gmail Using their depth measurements and the “We’re measuring what the bed topogra- .com; @katherinekornei), Freelance Science Jour- known extent of the ice, the team calculated phy looks like,” said Bohleber. That’s an nalist

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Earth & Space Science News Eos.org // 9 MEETING REPORT

of the challenges associated with smart city Cities Smarten Up development. Here are four examples, both good and bad, that stand out. and Go Green Amsterdam, Netherlands: The city cooper- ates with research institutes under the CIENS Urban Conference 2016: Smart and Green Cities—For Whom? umbrella of the Amsterdam Institute for Oslo, Norway, 13 October 2016 Advanced Metropolitan Solutions to develop tailored solutions to become a circular, con- nected, and vital city. Stockholm, Sweden: A former industrial site, Hammarby Sjöstad, is about to be con- verted into an ecocity district. A development of 140,000 new homes will take into account future climate change, biodiversity, and ecological values in addition to property developers’ interests. Technical, building, mobility, communication, and green- blue infrastructure issues were considered in an integrated way. Stakeholder collaboration is evident in the innovative vacuum waste suction system at the site, which collects and sorts waste more effectively than traditional waste systems. The system incinerates nonreusable waste, pro-

SA 2.0 (http://bit.ly/ccbysa2-0) 2.0 SA viding locally generated heat and electricity.

BY- At the same time, the system helps to prevent local air pollution, as garbage trucks are ren- dered obsolete. Trondheim, Norway: Not all development

DJANDY.COM, CC DJANDY.COM, progresses smoothly. Attendees discussed Rooftop gardens, like the one shown here atop Chicago’s City Hall, can improve urban water management while pro- how in Trondheim, officials granted develop- viding additional green spaces for residents. Participants at a meeting in Oslo, Norway, discussed the societal implica- ers permission to erect a several- story- high tions of such “smart and green” urban development that aims to reduce sprawl, shorten commutes, and use space building adjacent to one equipped with solar efficiently. panel walls, considerably reducing electricity production. Smart and green development requires cross- sectoral communication and ccording to the United Nations, two The conference was structured around four collaboration, and when communication thirds of the world’s population will topics: breaks down, smart development falters. live in cities by 2030. As cities around India: In 2016, the central government A the potential of smart and green cities, the world expand, they are pursuing smart and • launched a smart cities mission aimed at including concepts and strategies for devel- green development to reduce sprawl, shorten developing 100 sustainable and citizen– opment; long commutes and their associated pollution, friendly satellite towns to foster the urban sociotechnical and infrastructural changes and use space efficiently. Smart cities use • transition to sustainability. The mission necessary for smart and green city develop- information and communication technologies agenda addresses adequate water and electric- ment; to enhance the use of urban infrastructures. ity supply, sanitation and waste management, societal impacts and challenges of smart In October 2016, the Oslo Centre for Inter- • efficient urban mobility and affordable hous- and green city development; and disciplinary Environmental and Social ing, urban safety and security, health, educa- city case studies and shared experiences. Research (CIENS) invited participants to a • tion, and sustainable management of the 1– day conference in Norway (http://bit . ly/ Several presentations showed the potential environment, as well as robust Internet access SmartGreenCities2016). Approximately of innovation and technological change for and public participation via e-governance. 80 attendees, including urban planners and urban sustainability. Conference participants The conference was funded by CIENS and the entrepreneurs, participated in discussions of learned about modeling approaches to assess Research Council of Norway (grant 261528). the societal potential for and implications of social, economic, and ecological implications smart and green urban development trends. of future urban developments. Participants Strategies like green– blue infrastructure— also discussed indicators of feasibility, such as By Isabel Seifert- Dähnn (email: isabel.seifert@ that is, vegetation aligned with urban water political support or perceived benefits of niva.no), Norwegian Institute for Water Research, bodies—have proven to have a positive impact smart and green developments, along with Oslo, Norway; Marianne Millstein, Norwegian on human health, contribute to good urban how to recognize them. Such indicators can be Institute for Urban and Regional Research, Oslo, water management, and ameliorate the nega- used to help guide development decisions. Norway; and Akershus University College of tive consequences of climate change by The presentations featured case studies of Applied Sciences, Oslo, Norway; and Per Gunnar absorbing excess rainwater runoff or providing cities currently working to become greener Røe, Department of Sociology and Human Geog- a cooling effect during warm periods. and smarter but also drew attention to some raphy, University of Oslo, Oslo, Norway

10 // Eos May 2017 MEETING REPORT

plete regional flood assessments, and a con- Using Archives of Past Floods sideration of statistical and modeling tools that can be applied to flood reconstruction and to Estimate Future Flood Hazards identifying potential forcing mechanisms that include climate and land use change. Cross Community Workshop on Past Flood Variability The workshop highlighted the wealth of Grenoble, France, 27–30 June 2016 existing flood archive data, which span daily to millennial timescales. Despite the wealth of data, it is still challenging to compare different flood archive data sets or integrate these data into risk assessments. Some geographic areas, particularly Africa, Central and South America, and southern Asia, are underrepresented. At the meeting, the PAGES Floods Working Group agreed to create a joint database col- lecting all flood archive information to encourage systematic use of paleoflood indicators. A joint database will help handle different flood archives with different resolu- tions. It will also facilitate the development of hydrological and statistical tools to analyze floods from a multiarchive data set. In addition, the Floods Working Group identified the need to further involve climate modelers, hydrologists, and risk managers to improve understanding of the physical processes controlling the occurrence and magnitude of floods. Attendees agreed that these scientific collaborations and synergies could help contribute to the present debate about

Uta Löser climate drivers and the human impact on Floodwaters in the Elbe River reached an all- time high in August 2002, inundating this street in Dresden, Germany, flood generation. The use of climate and and requiring the evacuation of as many as 33,000 residents. Last June, the Floods Working Group of the Past Global hydrological modeling is critical to testing Changes project hosted a workshop to address the urgent need for better assessments of flood hazards by systemati- climate- flood relationships suggested by cally using evidence from past floods. interpretations derived from paleoflood archives. Within the next 3 years, the PAGES Floods orldwide, floods cause greater eco- events globally. The workshop aimed to coor- Working Group will foster further collabora- nomic damage and loss of human dinate further efforts to share disciplinary tions among scientists from different archive W life than any other type of natural experiences, promote interdisciplinary collab- communities and identify key questions for disaster. We urgently need better assessments orations, and integrate results and analysis. In the broader flood community. The focus will of flood hazards to reduce the societal impact all, 46 researchers from 16 countries attended. emphasize the exchange of experiences with of extreme floods caused by Earth’s rapidly the use of data about past floods; archive- changing climate, among other factors. specific methodological aspects; and the One way of assessing flood hazards is to Despite the wealth of advantages, challenges, and limitations of examine past floods using the records pro- flood archive data, it is each archive. vided by hydrological instruments. We can Researchers interested in joining the Floods extend this knowledge back through the Holo- still challenging to Working Group are encouraged to visit its cene or beyond using historical documents website (http:// bit . ly/ PAGES - floods). Video and natural archives (including alluvial, compare different data recordings of the workshop presentations are marine, and lake sediments; tree rings; and sets or integrate these available online at the meeting website cave formations). These extended records can (http:// bit . ly/ floods - workshop). provide valuable information about long-term data into risk flood trends. To promote the systematic use of paleoflood assessments. By Tina Swierczynski (email: tina . swierczynski@ evidence, the Floods Working Group of the awi.de), Alfred Wegener Institute, Bremerhaven, Past Global Changes (PAGES) project orga- Germany; and European Climate Research Alli- nized the first interdisciplinary workshop on The workshop held three sessions that ance, Brussels, Belgium; Monica Ionita, Alfred past flood variability. The meeting brought focused on a review of available flood archives Wegener Institute, Bremerhaven, Germany; and together geologists, geographers, historians, for the reconstruction of flood occurrence and David Pino, Department of Physics, Universitat meteorologists, climatologists, statisticians, magnitude, an assessment of multiarchive Politècnica de Catalunya and Institute for Space and hydrologists who investigate past flood flood approaches for more precise and com- Studies of Catalonia, Barcelona, Spain

Earth & Space Science News Eos.org // 11 OPINION

southeastern Indian Ocean seafloor had been Airline Flight Paths covered by echo soundings on 8 March 2014, when Malaysia Airlines flight MH370 went over the Unmapped Ocean missing. In mid-2014, the MH370 search area was moved to an area where data coverage was only 1% at the time the aircraft was lost. In January 2017, the search was suspended after 120,000 square kilometers had been mapped in efforts to find the aircraft. This is roughly one third of the area shown in Figure 1 and 0.0336% of the area of Earth’s ocean floor. In contrast, 86% of the eastern Mediterra- nean seafloor is mapped in the region where EgyptAir flight MS804 crashed on 19 May 2016, and 30% of the equatorial Atlantic is mapped where Air France flight AF447 fell on 1 June 2009. Comparing these three search regions at the same scale shows that ocean mapping varies enormously from region to region (Figure 2). The AF447 search region also illustrates the strong bias toward mapping of mid-ocean ridges at the expense of other areas [Smith, 1998].

Following the Airplanes To illustrate the extent of ocean mapping under aviation routes, we compiled a list of these routes using data from the Open Flights

nateemee/iStock.com project on GitHub (http://openflights.org/). Most airline passengers have no idea how little of the ocean floor beneath them has been mapped. These data list the originating and terminat- ing airports of regularly scheduled commercial flights and whether the service is non- arch marked 3 years since Malaysia lack of data and variance in quality hinder stop. Airlines flight MH370 disappeared, searches for missing aircraft, hazard assess- The actual path taken by any particular M and no trace of it on the seafloor has ments, and the pursuit of baseline scientific flight is determined as air traffic controllers yet been found. MH370 is believed to have knowledge. A modest effort could fix this lack direct each flight to a sequence of waypoints deviated from its intended flight path. Yet of data. and may change as weather and traffic loads even the typical routes taken by overseas change. We did not have this level of detail, flights are often over unknown seafloor. Uneven Coverage so we approximated flight routes as great cir- In fact, of the total over-ocean distance Only a small percentage of Earth’s seafloor cles connecting the originating and terminat- covered by all unique overseas flight routes, has been mapped [Copley, 2014; U.S. National ing airports. Because the Open Flights data do 60% is above unmapped areas. The quality of Ocean Service, 2014]. For example, Smith and not indicate the locations of intermediate mapping that does exist varies widely, and the Marks [2014] reported that only 5% of the stops, we analyzed only nonstop routes.

Fig. 1. Shaded relief images of the seafloor terrain in 800- × 600-kilometer regions containing the search areas for (left to right) EgyptAir flight MS804, Malaysia Airlines flight MH370, and Air France flight AF447. Approximate search areas are outlined in red. Seafloor terrain models are fromEMODnet Bathymetry Consortium [2016] and Weatherall et al. [2015]. Note the variances in search area, seafloor resolution, and ship tracks over the search area.

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2004] and mixing [Kunze and Llewellyn Smith, 2004] and climate forecasts [Jayne et al., 2004].

Addressing the Data Shortage All of Earth’s ocean floors deeper than 500 meters (i.e., exclusive of territorial waters and continental shelves) could be mapped by GPS- navigated MBES for 200 ship-years of effort (e.g., 40 ships working for 5 years), at a total Fig. 2. Depth measurements available at the time of the EgyptAir flight MS804, Malaysia Airlines flight MH370, and Air cost of $2–3 billion [Carron et al., 2001]. France flight AF447 crashes (black dots). According to the NASA scientists we con- sulted, this is less than the cost of NASA’s next mission to Europa. Some pairs of airports (e.g., New York’s which we call “available” data, are quite vari- We hope that our survey of the state of John F. Kennedy and London’s Heathrow) are able in their sampling density and in the age, ocean mapping from the perspective of over- served by many airlines flying many flights in technology, and accuracy of the sounding and ocean flight routes makes the relevance of each direction, but our analysis used each navigation systems used. All these variations ocean mapping and the current lack of map- unique pair of airports only once, regardless are irregularly distributed over the globe ping information clear to the public. of the frequency of flights between its air- [Smith, 1993; Wessel and Chandler, ports. 2011]. We generated a great circle route connect- We divided the global seafloor ing each airport pair, sampled that route area into equal-area square tiles every 1 kilometer of distance along its path, 1 nautical mile on a side and con- and then classified each sample point as sidered any tile mapped if it con- being over mapped ocean, over unmapped tained one or more available echo ocean, or not over ocean. We found that the soundings. For context, modern total distance along any individual route hull-mounted multibeam echo includes as many as 9201 kilometers flown sounders (MBES) map a swath of over unmapped ocean (Figure 3, top). Half of the ocean along the ship’s path, all over-ocean routes fly more than 200 kilo- but the vast majority of available meters over unmapped ocean, and 10% of the data (95% of coverage by area) are over-ocean routes fly more than 2000 kilo- point values—one depth mea- meters over unmapped ocean. The longest surement at one place, typically contiguous unmapped ocean segment along an analog measurement made by any one route (Figure 3, middle) is 2293 kilo- a wireline or a single-beam meters, traveled when flying between New acoustic sounder [Smith, 1993]. York’s Kennedy and Beijing’s Chongqing Our method produces a gener- Jiangbei airports. More than 20% of routes ous overestimate, with some tiles have a longest unmapped segment exceeding having only one sounding. In 200 kilometers. On most routes, more than addition, the majority of avail- half of the over- ocean portion is over able data are poorly navigated unmapped ocean (Figure 3, bottom). and error prone [Smith, 1993; We found a total of 19,024 unique nonstop Wessel and Chandler, 2011]. Even routes. Of these, 11,665 fly at least 1 kilometer by this generous definition, how- over ocean, and 10,686 fly at least 1 kilometer ever, only 8% of the global ocean over unmapped ocean. The total route dis- is mapped [Wessel and Chandler, tance is slightly more than 33.4 million kilo- 2011, Figure 8]. meters, 33% of which is over ocean, with 60% In the 92% of ocean area where of the total over-ocean distance being over depth has not been measured, unmapped ocean. These numbers do not satellite altimetry interpolates indicate the probability that an aircraft or a the gaps between available passenger is over unmapped ocean because soundings [Smith and Sandwell, our analysis is unable to account for the 1997; Becker et al., 2009; Weather- number of aircraft and passengers flying each all et al., 2015]. This approxima- route over a given period of time. tion strongly underestimates seafloor topography and rough- Our Criteria ness [Becker and Sandwell, 2008], An analysis like our airline route survey has with a variety of consequences Fig. 3. Great circle routes of commercial airline flights, showing (top) total to define how many depth readings it takes to that affect sciences, from earth- distance along each route that is over unmapped ocean, (middle) the list an area as mapped. Depth measurements quake and tsunami hazard longest segment of any route that is over unmapped ocean, and (bot- that can be readily obtained and used without assessment [Mofjeld et al., 2004] tom) the relative fraction of each route that is over unmapped ocean specialized access, licensing, or payment, to ocean circulation [Gille et al., (ratio of total unmapped ocean distance to total ocean distance).

Earth & Space Science News Eos.org // 13 OPINION

Smith, W. H. F., and D. T. Sandwell (1997), Global seafl oor topogra- All of Earth’s ocean floors deeper than 500 meters phy from satellite altimetry and ship depth soundings, Science, 277(5334), 1956–1962, https:// doi . org/ 10 . 1126/ science . 277 . 5334 . 1956. U.S. National Ocean Service (2014), How much of the ocean have we could be mapped at a total cost of $2–3 billion. explored?, http:// oceanservice . noaa . gov/ facts/ exploration . html. Weatherall, P., et al. (2015), A new digital bathymetric model of the world’s oceans, Earth Space Sci., 2(8), 331–345, https:// doi . org/ 10 .1002/ 2015EA000107. Wessel, P., and M. T. Chandler (2011), The spatial and temporal distri- Acknowledgments Copley, J. (2014), Just how little do we know about the ocean fl oor?, bution of marine geophysical surveys, Acta Geophys., 59(1), 55–71, Sci. Am., 9 October 2014, http:// www . scientifi camerican. com/ article/ https:// doi . org/ 10 . 2478/ s11600 - 010 - 0038 - 1. Comments by two anonymous reviewers just - how - little - do - we - know - about - the - ocean - fl oor/. improved the manuscript. The views EMODnet Bathymetry Consortium (2016), EMODnet digital bathymetry (DTM), http:// doi . org/ 10 . 12770/ c7b53704 - 999d - 4721 - b1a3 expressed here are solely those of the authors -04ec60c87238. and do not constitute a statement of policy, Gille, S. T., E. J. Metzger, and R. Tokmakian (2004), Seafl oor topogra- By Walter H. F. Smith (email: walter . hf . smith@ decision, or position on behalf of the National phy and ocean circulation, Oceanography, 17(1), 47–54, https:// doi noaa . gov) and Karen M. Marks, Laboratory for .org/ 10 . 5670/ oceanog . 2004.66. Oceanic and Atmospheric Administration or Satellite Altimetry, National Oceanic and Atmo- Jayne, S. R., L. C. St. Laurent, and S. T. Gille (2004), Connections Service Hydrographique et Oceanographique between ocean bottom topography and Earth’s climate, Oceanogra- spheric Administration, College Park, Md.; and de la Marine or the U.S. or French govern- phy, 17(1), 65–74, https:// doi . org/ 10 . 5670/ oceanog . 2004 . 68. Thierry Schmitt, Service Hydrographique et Kunze, E., and S. G. Llewellyn Smith (2004), The role of small- scale ments. topography in turbulent mixing of the global ocean, Oceanography, Oceanographique de la Marine, Brest, France 17(1), 55–64, https:// doi . org/ 10 . 5670/ oceanog . 2004 . 67. Mofj eld, H. O., et al. (2004), Tsunami scattering and earthquake faults References in the deep Pacifi c Ocean, Oceanography, 17(1), 38–46, https:// doi Becker, J. J., and D. T. Sandwell (2008), Global estimates of seafl oor .org/ 10 . 5670/ oceanog . 2004 . 65. For more on efforts to map slope from single- beam ship soundings, J. Geophys. Res., 113, Smith, W. H. F. (1993), On the accuracy of digital bathymetric data, C05028, https:// doi . org/ 10 . 1029/ 2006JC003879. J. Geophys. Res., 98(B6), 9591–9603, https:// doi . org/ 10 . 1029/ the seafloor in the search Becker, J. J., et al. (2009), Global bathymetry and elevation data 93JB00716. at 30 arc seconds resolution: SRTM30PLUS, Mar. Geod., 32(4), Smith, W. H. F. (1998), Seafl oor tectonic fabric from satellite altimetry, 355–371, https:// doi . org/ 10 . 1080/ 01490410903297766. Annu. Rev. Earth Planet. Sci., 26, 697–747, https:// doi . org/ 10 . 1146/ area for Malaysia Airlines Carron, M. J., P. R. Vogt, and W.- Y. Jung (2001), A proposed interna- annurev . earth . 26 . 1 . 697. tional long- term project to systematically map the world’s ocean Smith, W. H. F., and K. M. Marks (2014), Seafl oor in the Malaysia flight MH370, see page 24. fl oors from beach to trench: GOMaP (Global Ocean Mapping Pro- Airlines fl ight MH370 search area, Eos Trans. AGU, 95(21), 173–174, gram), Int. Hydrogr. Rev., 2(3), 49–55. https:// doi . org/ 10 . 1002/ 2014EO210001. Read it first on .

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14 // Eos May 2017 OPINION

as a period of below-average precipitation. Defining Snow Drought “Hydrological drought” refers to water stor- ages and fluxes falling below long-term aver- and Why It Matters ages. Then there’s “anthropogenic drought,” the phenomenon of how most projections of future drought include increases in severity n 12 February, water resource manag- different implications for water supply fore- and duration that reflect increasing water ers at the Oroville Dam in California casting and management. To clarify future demand due to warming [Diffenbaugh et al., O issued an evacuation warning that uses of this terminology, we propose a new 2015]. Add to this the emerging term “snow forced some 180,000 residents to relocate to classification to differentiate “dry snow drought,” and you now have a fairly complex higher ground. The story of how conditions drought,” due to lack of precipitation, from picture. got to this point involves several factors, but “warm snow drought,” where temperatures Although meteorological droughts remain two clearly stand out: the need to prevent prevent precipitation from accumulating on difficult to predict in the western United water shortages during a record drought, fol- the landscape as a snowpack. States, widespread declines in snowpack have lowed by one of the wettest been observed across the region. October– February periods in Cali- These declines, which have been fornia history. We propose a new classification to attributed to warming air tempera- The situation in winter 2016 at tures and related trends, reflect Oroville Dam highlighted difficul- differentiate “dry snow drought” from earlier snowmelt and shifts from ties that many reservoir managers “warm snow drought.” snow to rain [e.g., Hamlet et al., face in managing flood risks while 2007; Harpold et al., 2012]. simultaneously storing water to Despite decades of research on mitigate severe droughts and changing snowpacks, recent smaller snowpacks. Central to this difficulty is Here we use snow conditions during winter extreme lows in snowpacks have revealed the the idea of “snow drought,” a term gaining 2015 on the West Coast of the United States to extent of the unique challenges that snow traction in both scientific and lay literature. illustrate the difference. We also show how droughts pose for water managers. For scien- Snow drought refers to the combination of snow drought, if not properly incorporated tists and resource managers to plan for chal- general drought and reduced snow storage. into management decisions, can heighten the lenges to come, they need to be equipped with However, among references to snow drought, potential for emergency situations like the one solid definitions of all forms of drought, snow we observe conditions that reflect a lack of that unfolded at Oroville Dam. drought included. winter precipitation or a lack of snow accumulation during near-normal winter precipita- Subtle Definitions Winter 2015 on the West Coast: tion. with Important Implications A Tale of Two Snow Droughts These two uses of the term snow drought Drought means different things in different The 2015 winter (from November 2014 through have different scientific underpinnings and contexts. “Meteorological drought” is defined March 2015) highlighted two types of snow drought and their challenges for water management in the westernmost United States. The winter was abnormally warm, with temperatures in the Pacific Northwest (Washing- ton, Oregon, and Idaho) averaging 3.0°C above normal and temperatures in the Sierra Nevada (California and Nevada) averaging 3.4°C above normal. Winter precipitation, on the other hand, varied considerably from north to south, with the Pacific Northwest receiving 70%–120% of its normal precipitation while the Sierra Nevada received only 40%–80% of normal (Figure 1). Despite large differences in the amounts and timing of winter precipitation, the snow water equivalent (SWE) in both regions was less than average. On 1 April 2015, snowpack contained between about 50% of the water it usually holds in the Pacific Northwest and a startlingly low 5% in the Sierra Nevada (Fig- ure 1). These low SWE amounts resulted from two

Max Whittaker/Getty Images Max Whittaker/Getty distinct drivers of snow drought. Snow A snowboarder threads his way through patches of dirt at Squaw Valley Ski Resort on 21 March 2015 in Olympic Val- drought in the Pacific Northwest reflected a ley, Calif. lack of snow accumulation due to warm tem-

Earth & Space Science News Eos.org // 15 OPINION

peratures that increased rainfall and melted snowpacks, despite near-normal precipitation. Snow drought in the Sierra Nevada also reflected similarly warm temperatures but was enhanced beyond the Pacific North- west’s deficits by the lack of winter precipitation.

Effects of Winter 2015 on Downstream Water Resources Streamflow responses to the different snow droughts differed considerably between the regions. The rainfall that replaced snowfall in the Pacific Northwest yielded large winter peak streamflow events (Figure 1). With most of the water leaving basins in winter rather than during the usual snowmelt season, summer streamflow was far below normal. With less precipitation and warmer temperatures, streamflow in the Sierra Nevada lacked both large winter flows and its usual spring snowmelt pulse and fell to extremely low levels early in the summer. Streamflow responses generally depend on topography and geology of a given basin but in this case reflect these different snow conditions across both regions. The distinct responses illustrated here have large implica- PRISM, NRCS/CA DWR; USGS DWR; PRISM, NRCS/CA tions for water management and ecological Fig. 1. (left) Precipitation from 1 November 2014 to 31 March 2015 was near normal in the Pacific Northwest and well water availability. below normal in the Sierra Nevada (colored map), whereas 1 April 2015 snow water equivalent was below average However, the same term, snow drought, across the domain (colored dots). (right) These differences in precipitation and snowpack led to starkly different was used to describe snow conditions in both streamflow responses at two characteristic U.S. Geological Survey stream gauges. regions. A more nuanced definition of snow drought could facilitate discussions of, planning for, and responses to droughts and changing snowpacks. point: Few drought metrics include storage flows, requiring that large winter flows pass and release of snow water. For example, the immediately through the reservoirs to main- Defining and Quantifying Snow Drought Palmer drought severity index (PDSI) used by tain extra storage We propose more precise terms to distinguish the U.S. Drought Monitor treats all precipita- Snow reservoirs, the water stored in moun- between the two different snow droughts tion as rain. This simplification means that tain snowpacks, aid both management pur- observed in the Pacific coast states in winter the PDSI cannot distinguish between warm poses. Snowpacks are particularly important 2015: dry snow drought for precipitation- and dry snow droughts. to western water supplies because they histor- driven snow drought and warm snow drought Physically based models, such as the North ically persisted into summer when water for temperature- driven snow lack. Both types American Land Data Assimilation System demand is the highest and prediction of flows of snow drought have SWE that is notably less (NLDAS) drought monitor, represent accumu- is more accurate (being based on snow on the than normal. lating and melting snowpacks, but their ground rather than on rains to come). The In a warm snow drought, scenarios where results remain spatially coarse and challeng- natural reservoirs of water formed by the SWE is low but precipitation (P) is not (thus a ing to verify over large areas. Given different snowpacks expand the usefulness and reliabil- low SWE:P ratio) reflect that a larger than nor- effects of warm versus dry snow drought on ity of man-made reservoirs by releasing water mal amount of precipitation has fallen as rain water-related decision making, drought mon- predictably and closer to times of high rather than snow, that an unusual amount of itoring needs to better distinguish between demand. melt has occurred, or both [e.g., Cooper et al., the two. Winter precipitation that falls as rain gen- 2016]. If the SWE and precipitation are nearly erates much greater flood risk than when equal (SWE:P is close to 1) and SWE is below Snow Drought and Water Management storms deliver snowfall. So most western normal, winter precipitation must also be A reservoir manager is faced with balancing water management decisions, such as the below normal, and the lack of SWE is likely a the following: amount of water to release from a spillway, reflection of low precipitation—a dry snow • capturing inflows to reservoirs so that rely on accurate forecasts of near-term rains drought. they will still be available for use in the sum- and eventual seasonal streamflow amounts, The challenge of differentiating dry and mer the latter of which depends on the amount of warm snow droughts using drought monitor- • maintaining enough empty space in res- water in the region’s “snow reservoirs,” which ing networks highlights a common weak ervoirs to capture or ameliorate large flood is reduced by snow droughts of either flavor.

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In the context of reservoir management, as much water as possible to provide water managers manage today and plan for the snow drought presents different challenges. during what might be a summer drought. future. During a dry snow drought, streamflows are In the case of Oroville Dam, water managers Another monitoring challenge is the scar- low, and inflows to reservoirs are reduced all battled with a reservoir that was beyond capac- city of precipitation and SWE measurement at year long. If one knew that such a drought ity but that contained only 46% as much water the highest elevations. Although emerging would occur, precipitation and streamflow on the same date in 2015 in the midst of the snow remote sensing methods are suited for moving downstream might be captured and snow drought described above (and only 30% as filling in gaps in traditional observation sys- stored in dam- impounded reservoirs. much water by September 2015; see http://bit tems, expanding ground- based observations In a warm snow drought, streamflow arrives .ly/ OroStorage). Not knowing how the winter of precipitation, SWE, and phase into higher earlier than normal, but the prospects of a rich would play out, California’s water managers elevations soon will be critical to developing spring snowmelt season are limited. Reservoir began storing water during fall rains to buffer the long-term records needed to define snow management is then faced with immediate against a potential developing snow drought, drought and its causes over time [Dettinger, flood risks followed by subsequent drought but instead, they got a record wet winter. 2014]. conditions. Concerted efforts by scientists, agency-run The (Unknown) Hydrological Effects monitoring networks, water managers, and California and the Case of Oroville Dam of Snow Drought policy makers will be needed to address the Western water woes are dynamic. To illustrate The definitions of warm and dry snow drought pending prospects of snow drought and how it how quickly fortunes can change, consider the help to frame science that is fundamental to fits into decision making. For example, what remarkable transition that this past fall and water management challenges facing snow- should water managers do to deal with nearly winter brought to California’s snowpacks and dominated regions: record-breaking snow droughts and flood streamflows after multiple years of drought. • Which form of snow drought (dry or years in rapid succession? We have only to October through December 2016 were very warm) is likely to dominate in different areas look to the reservoir behind Oroville Dam over wet months in northern California (with under future climate scenarios? the past 3 years to see these challenges illus- precipitation totals about 170% of normal by • How and where can monitoring and trated in dramatic ways. 1 January 2017), but because several of the management infrastructure be updated to In response to changing snowpacks and storms were warm rainfall, snowpack in Cal- meet the challenges associated with increas- more extreme droughts, we will need a com- ifornia by 1 January was only 64% of normal ing warm or dry snow drought? mon but nuanced definition of snow drought (http://bit.ly/snowpacklow). The extra pre- Climate models suggest that shifts from to facilitate efforts and better manage our cipitation quickly ran off into impound- mostly dry to increasingly warm snow drought water supplies. With such definitions in hand, ments and wetted the landscape. A long could be a consequence of regional warming we may be better equipped to face future water string of storms that followed in January and [Pierce and Cayan, 2013]. However, shifts to woes in the West. February filled reservoirs, in some cases to warm snow drought are expected to depend the brim. unevenly on elevation, moisture sources and References The early winter snowpack deficits, how- transport, and the timing of precipitation. Cooper, M. G., A. W. Nolin, and M. Safeeq (2016), Testing the recent snow drought as an analog for climate warming sensitivity of Cas- ever, signaled a real possibility that this com- Thus, retrospective analyses of warm versus cades snowpacks, Environ. Res. Lett., 11(8), 084009, https:// doi . org/ ing summer might bring a return to drought dry snow drought are needed to identify areas 10 . 1088/ 1748 - 9326/ 11/ 8/ 084009. conditions, as many of the region’s reservoirs that have begun to shift from dry to warm (or Dettinger, M. (2014), Climate change: Impacts in the third dimension, Nat. Geosci., 7, 166–167, https:// doi . org/ 10 . 1038/ ngeo2096. were still below average following the 2012– to warm and dry) snow drought predomi- Diffenbaugh, N. S., D. L. Swain, and D. Touma (2015), Anthropogenic 2015 drought. So there was a need to impound nance, and networks and sensors for monitor- warming has increased drought risk in California, Proc. Natl. Acad. Sci. U. S. A., 112(13), 3931–3936, https:// doi . org/ 10 . 1073/ pnas ing the full range of .1422385112. snow conditions are Hamlet, A. F., P. W. Mote, and M. P. Clark (2007), Twentieth-century critical to better trends in runoff, evapotranspiration, and soil moisture in the western United States, J. Clim., 20(8), 1468–1486, https:// doi . org/ 10 . 1175/ characterizing cur- JCLI4051. 1. rent and future snow Harpold, A., et al. (2012), Changes in snowpack accumulation and ablation in the intermountain west, Water Resour. Res., 48, W11501, droughts. https:// doi . org/ 10 . 1029/ 2012WR011949. We also need bet- Pierce, D. W., and D. R. Cayan (2013), The uneven response of differ- ter measurements of ent snow measures to human- induced climate warming, J. Clim., 26(12), 4148–4167, https:// doi . org/ 10 . 1175/ JCLI - D - 12 - 00534.1. what phase (rain or Rajagopal, S., and A. A. Harpold (2016), Testing and improving tem- snow) is falling perature thresholds for snow and rain prediction in the western during precipitation United States, J. Am. Water Resour. Assoc., 52(5), 1142–1154, https:// doi . org/ 10 . 1111/ 1752 - 1688 . 12443. events. Mixes of rain and snow from place to place, storm to storm, and year to By Adrian A. Harpold (email: aharpold@ cabnr year are almost .unr . edu; @NV _ Mtn _ Ecohydro), Department of always inferred indi- Natural Resources and Environmental Science, rectly from tempera- University of Nevada, Reno; Michael Dettinger

Adrian Harpold ture or changes in (@Mdettinger), National Research Program, Students from the University of Nevada, Reno, learn how to measure streamflow at SWE [Rajagopal and U.S. Geological Survey, Carson City, Nev.; and Sagehen Creek Field Station in California’s Sierra Nevada during a small rain- on- snow Harpold, 2016]. But Seshadri Rajagopal (@SeshRajagopal), Division event in March 2016. Winter rain during drought, or warm snow drought, has different direct knowledge of Hydrologic Sciences, Desert Research Institute, management implications than dry winters, or dry snow drought. could help water Reno, Nev.

Earth & Space Science News Eos.org // 17 EVALUATING THE HIGHEST TEMPERATURE EXTREMES IN THE ANTARCTIC

By Maria de Los Milagros Skansi, John King, Matthew A. Lazzara, Randall S. Cerveny, Jose Luis Stella, Susan Solomon, Phil Jones, David Bromwich, James Renwick, Christopher C. Burt, Thomas C. Peterson, Manola Brunet, Fatima Driouech, Russell Vose, and Daniel Krahenbuhl

Sunshine over the Antarctic Peninsula. Just how warm can Antarctica get?

18 // Eos May 2017 n 21 July 1983, the lowest temperature committee of climatologists and meteorologists ever recorded on Earth occurred at a associated with Antarctic temperature measure- Russian research station in central Ant- ments to establish the highest temperature extremes arctica: The thermometer at the site of the region. read −89.2°C (−128.6°F). Their investigation verified what is, as of now, the But it’s not just the lowest lows that current record high: a balmy 19.8°C (67.6°F). This Ohave caught the attention of scientists in the Antarc- temperature was observed on 30 January 1982 at Signy tic. Especially in the face of climate change, Research Station at Factory Cove, Borge Bay, on Signy researchers have also begun to investigate how warm Island. This record, collected with instruments that the planet’s southernmost region can get. follow WMO’s standards, has now been made public Officially investigating, documenting, and verify- by WMO (http:// bit . ly/ WMO - Antarctic -Warm). ing such high temperature extremes is the business Also recently made public are two temperature of the World Meteorological Organization (WMO) extremes in two distinct climate regimes of Antarc- Commission for Climatology (CCl). For this purpose, tica: its low- lying ice sheet and continent and its high the WMO CCl has created an international evaluation and dry plateau. On the continent, CCl verified that a oliver.dodd

Earth & Space Science News Eos.org // 19 David Mikolajczyk

Installation and maintenance of an AWS station in the Antarctic of a type similar to the D-80 AWS, which recorded the highest temperature seen on the Antarctic Plateau (−7.0°C on 28 December 1989).

high- temperature extreme of 17.5°C (63.5°F) occurred on The committee then examined the evidence for estab- 24 March 2015 at the Argentine research base Esperanza, lishing the highest temperature of the region as 19.8°C located near the northern tip of the Antarctic Peninsula. An (67.6°F), observed on 30 January 1982 at Signy Research observation of −7.0°C (19.4°F), made on 28 December 1989 at Station (60°43′S, 45°36′W, WMO station 88925) at Factory an automatic weather station (AWS) site, D-80, located Cove, Borge Bay. Signy Research Station is situated on the inland of the Adélie Coast, has been verified by CCl to be the eastern shore of Signy Island (Figure 1). The research sta- highest temperature recorded on the Antarctic Plateau. tion was established in 1947 and operated as a year-round The committee noted that the extremes at the Signy, station until 1996, when it was reduced to summer-only Esperanza, and D-80 stations occurred during periods of operation. Figure 2a shows a photograph of the station in warm-air advection. At Signy and Esperanza, warming from 1967. leeward winds (foehn warming) also contributed, whereas at At the time of the record observation, the Signy D-80 solar heating under clear skies at high elevation was a Research Station was operating a very basic climatological major contributory factor. This investigation highlights the observing program. There were no dedicated meteorolog- need to continually monitor all of the Antarctic region to ical observers at the station, and biological research ensure that we have the best possible data for climate assistants carried out the observations. These assistants change analysis at both regional and global scales. carried out full synoptic observation at 09:00 local time (12:00 coordinated universal time (UTC)) every day. In Highest Temperature for the Antarctic Region: addition, they collected maximum and minimum ther- 19.8°C, Signy Research Station, 30 January 1982 mometer readings at 09:00 and 21:00 local time (12:00 Knowledge and verification of extreme temperatures are and 00:00 UTC, respectively). The station used mercury- important in the study of global and regional climate in-glass thermometers located in a Stevenson screen change. They are also key in the analysis of observation shelter. At 12:00 UTC every day, a duty assistant changed practices and proper equipment selection. Similar to how the mercury-in- steel distant-reading thermometer that WMO has documented extremes for other regions of the provided a continuous record of temperature on a circular world during the past 10 years, an evaluation committee chart. recently finished its examination of record-high extremes Between 25 and 27 January 1982, 12:00 UTC tempera- for the Antarctic region. tures registered just above freezing but rose on and after But what exactly is the Antarctic region? The WMO Ant- 28 January. On 30 January the 12:00 UTC temperature read arctic temperature extremes committee recommended +9.6°C, and the maximum thermometer reading over the that “Antarctic region” be defined as “all of the land and previous 12 hours was logged as +19.8°C (67.6°F), a record ice shelves south of 60°S latitude.” for Signy Research Station.

20 // Eos May 2017 Weather Conditions graphic interpretation of the Antarctic as a single landmass. During the High- Temperature Extreme One important goal of the committee was to improve public At the time of the observed record temperature, a trough education about the Antarctic’s quite distinct climatic of low surface pressure lay across Drake Passage, connect- regimes. Most of the general public is often surprised to ing low- pressure centers west of the Antarctic Peninsula learn how mild some parts of the Antarctic can be. and west of southern Chile. Simultaneously, a ridge of high Consequently, the committee recommended two new pressure extending southward from the South Atlantic subregional temperature extremes: (1) the highest tem- drove a strong northwesterly pattern of circula- perature recorded on, or immediately adjacent tion in the vicinity of the South Orkney to, the Antarctic continent and (2) the Islands. This can be seen in the Euro- highest temperature recorded at or pean Centre for Medium- Range above 2500 meters (the interior Weather Forecasts’ ERA- plateau region of the Antarctic). Interim reanalysis [Dee et al., 2011], one of the top com- Highest Temperature on puter model reconstruc- the Continent: 17.5°C,

tions of the weather of Esperanza Research

the past 150 years (Fig- n Base, 24 March 2015

ure 3a). This flow P The committee evalu-

resulted in the south- a ated the evidence for an

r U ward movement of observation of 17.5°C

warm midlatitude air e (63.5°F) made on

e from the South Atlantic i 24 March 2015 at the c

sector. l Argentine research base a c i h Although this advec- p Esperanza. If verified, a r g tion of warm air was o this reading would be the e G almost certainly a neces- f highest temperature o l o sary condition for achieving o recorded on the Antarctic h c S these record temperatures, it ity continent. rs ve is likely that local orographic ni Esperanza is located near the e U tat effects also played a role. Signy lies a S northern tip of the Antarctic Penin- zon in the lee of Coronation Island when Ari sula just east of the Antarctic Peninsula the wind flows from the northwest. The mountains, which rise to around 1000 meters island rises to 1265 meters and may thus cause a near this location (Figure 1). This temperature significant foehn warming effect. The distant- reading extreme occurred on the day following a reading of 17.4°C thermometer record shows a rapid increase in temperature (63.3°F) measured at the Argentine research base Maram- around 21:00 local time and a rapid decrease at around bio, about 100 kilometers southeast of Esperanza, on 02:30, both of which are characteristic of foehn events. 23 March 2015. In addition, the hygrograph record shows two very Temperature observations for Esperanza station rapid decreases in humidity on 29 January, the first (63°24'S, 56°59'W, elevation of 13 meters) began in January around 09:00 local time and the second around 21:00, 1953 and have continued since. The instrumentation con- which would support the idea that a foehn effect played sists of a common (mercury- in- glass) maximum/mini- an important role. Although the anemograph does not mum thermometer that was installed on 3 December 2005 show particularly marked wind speed changes at these within a pagoda- style naturally vented meteorological times, there is a transition from almost calm conditions shelter. Figure 2b shows a photograph of the instrument to very gusty, moderate winds at around 22:30 local time shelter in 2016. on 29 January, followed by a dramatic increase in wind ERA reanalysis for this location at the time of the tem- speed at around 02:30 local time on 30 January. perature extreme shows a northwest–southeast warm Past researchers have noted the importance of the high- pressure ridge stretching from South America to the foehn warming in driving Antarctica warm events [e.g., Antarctic Peninsula in concert with a cold trough of low Elvidge and Renfrew, 2016; Cape et al., 2015; Speirs et al., pressure lying over the far South Pacific near 120°W. 2010]. Consequently, after the committee assessed the Together, these features drove a strong northwesterly cir- station’s compliance with WMO standards, as well as culation that was associated with warm air advection and foehn occurrence, it unanimously recommended accep- strong winds perpendicular to the mountain chain in the tance of this observation as the highest temperature northern part of the peninsula, conducive to the develop- recorded for the Antarctic region. ment of a foehn at Esperanza (Figure 3b).

Deﬁning Subregions Following the acceptance of the Signy observation of 19.8°C as the highest temperature recorded in the Antarc- Fig. 1. The area of the United Nations/WMO Antarctic region (all lands tic region (all lands south of 60°S), the committee addressed and ice south of 60°S) with the 2500- meter elevation delineated (using the concern that such an acceptance of an island observa- the digital terrain model of Liu et al. [2001]). Locations of the three high- tion measured at 60°43′S does not match the common geo- temperature extreme stations (Signy, Esperanza, and D- 80) are shown.

Earth & Space Science News Eos.org // 21 A. rence, the committee recommended unanimously to accept the observation of 17.5°C (63.5°F) made on 24 March 2015 at the Argentine research base Esperanza as the highest temperature recorded for the Antarctic continent.

Highest Temperature on the Plateau For the Antarctic Plateau, the committee evaluated the evidence for an observation of −7.0°C (19.4°F) made on 28 December 1989 at D-80 AWS, located in the interior of the Adélie Coast (70°6′S, 134°53′E; see Figure 1). The AWS operated from 14 Janu- ary 1983 to 1 January 2001 at an elevation of 2500 meters [Wendler et al., 1993]. The temperature was recorded with a Weed B. C. platinum resistance thermometer sensor with an accuracy of ±0.5°C. Figure 2c shows a photograph of the station upon installation in 1983. On 28 December 1989, ERA reanalysis showed that a high- pressure ridge situated west of Tasmania around 130°E over the Southern Ocean channeled warm air southward toward D- 80 (Figure 3c). This strong ridge had been persistent over the area for the previous 4 days. The committee noted that at high elevations, insola-

WMO tion under clear skies will warm the air, Fig. 2. Photographs of the three stations evaluated for the Antarctic extreme high tempera- contributing to the record-high temperatures. (a) Signy Research Station in 1985 (60°43′S, 45°38’W; the Stevenson screen may be ture. It was noted that in some cases high seen behind the station buildings in the extreme right of the picture), (b) Esperanza station insolation can cause spurious warming of in 2016 (63°24′S, 56°59′W), and (c) D-80 AWS in 1993 (70°6’S, 134°53’E). the temperature sensor if the sensor is not properly ventilated, but in this situation, the committee concluded that there should Consequently, after careful evaluation of the evidence have been sufficient ventilation of the sensor. with regard to quality of observation, type and calibration Given these considerations and after ensuring that data of equipment, and site placement, as well as foehn occur- were collected in compliance with WMO standards, the

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22 // Eos May 2017 committee recommended unanimously to accept the observation as the highest temperature recorded for the Antarctic Plateau.

Importance of Establishing Antarctic Extremes As with all WMO evaluations of extremes (e.g., temperature, pressure, wind, etc.), the extremes presented here are the highest observed temperatures placed before the WMO for adjudication that passed WMO’s standards for such data. It is possible, indeed, likely, that greater extremes can and have occurred in the Antarctic but have gone unreported. Temperature extremes in the Antarctic are important to evaluate and document in the face of changing regional and global climate. Only through continual monitoring of the entire Antarctic region can we ensure that we have the best possible data for climate change analysis at both regional and global scales.

Acknowledgments Meteorological observations at Signy were funded by the U.K. Natural Environment Research Council. The meteorological observations at the D-80 AWS site are based upon work supported by the Division of Polar Programs, National Science Foundation, under grants ANT-1245663 and PLR-1543305. We thank Institut Polaire Français Paul- Emile Victor for its joint support of D-80 AWS. M.B. and P.J. were supported by the European Union–funded project “Uncertainties in Ensembles of Regional Reanalyses” (UERRA, FP7- SPACE- 2013-1 project number 607193). M.B. was also funded by the Spanish Ministry of Economy and Competitiveness (MINECO) CGL2014- 52901- P grant.

References Cape, M. R., et al. (2015), Foehn winds link climate- driven warming to ice shelf evolution in Antarctica, J. Geophys. Res. Atmos., 120, 11,037–11,057, https:// doi . org/ 10 . 1002/ 2015JD023465. Dee, D. P., et al. (2011), The ERA- Interim reanalysis: Configuration and performance of the data assimilation system, Q. J. R. Meteorol. Soc., 137, 553–597, https://doi.org/10.1002/qj.828. Elvidge, A. D., and I. A. Renfrew (2016), The causes of foehn warming in the lee of mountains, Bull. Am. Meteorol. Soc., 97(3), 455–466, https:// doi . org/ 10 . 1175/ BAMS - D - 14 - 00194. 1. Liu, H., et al. (2001), Radarsat Antarctic Mapping Project digital elevation model, version 2, https:// nsidc .org/ data/docs/daac/nsidc0082_ramp_dem.gd.html, NASA Natl. Snow and Ice Data Cent. Distrib. Act. Arch. Cent., Boulder, Colo. [Accessed 29 August 2016.] Speirs, J. C., et al. (2010), Foehn winds in the McMurdo Dry Valleys, Antarctica: The origin of extreme warming events, J. Clim., 23, 3577–3598, https:// doi . org/ 10 . 1175/ 2010JCLI3382. 1. Wendler, G., et al. (1993), Katabatic winds in Adélie Coast, in Antarctic Meteorology and Climatology: Stud- ies Based on Automatic Weather Stations, Antarct. Res. Ser., vol. 61, edited by D. H. Bromwich and C. R. Stearns, pp. 23–46, AGU, Washington, D. C., https:// doi . org/ 10 . 1029/ AR061p0023. Author Information Maria de Los Milagros Skansi, Departamento Climatología Servicio Meteo- rológico Nacional, Buenos Aires, Argentina; John King, Atmosphere, Ice and Climate Team, British Antarctic Survey, Cambridge, UK; Matthew A. Lazzara, Madison Area Technical College, Madison, Wis.; and University of Wisconsin– Madison; Randall S. Cerveny (email: cerveny@ asu . edu), School of Geographical Sciences, Arizona State University, Tempe; Jose Luis Stella, Departamento Clima- tología Servicio Meteorológico Nacional, Buenos Aires, Argentina; Susan Solo- mon, Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge; Phil Jones, Climatic Research Unit, School WMO of Environmental Sciences, University of East Anglia, Norwich, U.K.; and Center of Excellence for Climate Change Research and Department of Meteorology, King Abdulaziz University, Jeddah, Saudi Arabia; David Bromwich, Byrd Polar and Cli- Fig. 3. The 500- hectopascal height analyses (geopotential mate Research Center, Ohio State University, Columbus; James Renwick, Victoria meters, analogous to the pressure pattern at around University of Wellington, N.Z.; Christopher C. Burt, The Weather Company, IBM, 5 kilometers in altitude, above the highest parts of the Ant- Atlanta, Ga.; Thomas C. Peterson, Commission for Climatology, World Meteoro- arctic Plateau) using the ERA- Interim reanalysis [Dee et al., logical Organization, Geneva, Switzerland; Manola Brunet, Centre for Climate 2011] for (top) 00:00 UTC, 30 January 1982, when Signy Change, University Rovira i Virgili, Tarragona, Spain; and Climatic Research Unit, Research Station recorded a maximum temperature of School of Environmental Sciences, University of East Anglia, Norwich, U.K.; Fatima 19.8°C; (middle) 00:00 UTC, 24 March 2015, when Esper- Driouech, Climate Studies Service, Direction de la Météorologie Nationale, Casa- anza station recorded a maximum temperature of 17.5°C; blanca, Morocco; Russell Vose, National Centers for Environmental Information, and (bottom) 00:00 UTC, 28 December 1989, when D-80 National Oceanic and Atmospheric Administration, Asheville, N.C.; and Daniel AWS recorded a maximum temperature of −7°C. Krahenbuhl, School of Geographical Sciences, Arizona State University, Tempe

Earth & Space Science News Eos.org // 23 GEOLOGICAL INSIGHTS FROM THE SEARCH FOR MALAYSIA AIRLINES FLIGHT MH370

By Kim Picard, Brendan Brooke, and Millard F. Cofﬁ n

24 // Eos May 2017 he tragic disappearance of Malaysia Airlines flight MH370 on 8 March 2014 led to a deep- ocean search effort of unprecedented scale and detail. Between June 2014 and June 2016, geophysical survey teams aboard ships used echo sounding techniques to create state- of- the- art maps of the seafloor topography and profiles of the sediments below the ocean floor in a zone spanning about 279,000 square kilome- Tters of the southeastern Indian Ocean. The curved search swath is 75 to 160 kilometers wide, and it sweeps from northeast to southwest. It centers on Broken Ridge and extends

One by-product of the search for the missing Malaysian Airlines ﬂ ight MH370 is a view with an unprecedented level of detail of the landscape deep in the Indian Ocean. This 3-D image shows seamounts; the largest seamount in this area, about 1.5 kilometers high, appears in the middle. Dropping from the horizon is the Diaman-

Kim Picard and Jonah Sullivan tina Trough. Vertical exaggeration is 3 times.

Earth & Space Science News Eos.org // 25 maps in this region had an average spatial resolution of more than 5 square kilometers, but the new maps resolve features smaller than 0.01 square kilometer (an area slightly larger than a soccer field). Crucially, the new data provided the geospatial framework for the last phase of the search, in which search teams deployed deepwater, high- resolution acoustic and optical imaging instruments with the ability to identify aircraft wreckage (see http:// bit . ly/ MH370 - bathymetry).

A Sharper Focus on the Ocean Floor The global ocean covers 71% of Earth’s surface, yet the ocean floor remains poorly studied compared with the land surface. In particular, knowledge of ocean floor topography is sparse because light cannot penetrate the deep ocean and acoustic mapping techniques are relatively inefficient in mapping its floor. Most of the ocean floor (85%–90%) has been mapped indirectly using satellite-derived gravity data, which yield a spatial resolution of about 5 kilometers [Weatherall et al., 2015]. By comparison, topographic maps of even the most remote land areas on Earth resolve features approximately 50 meters across, and topographic maps of the Moon, Mars, and Venus resolve 100- meter features [Copley, 2014]. Ship-mounted multibeam echo sounders that use sound waves that echo off the ocean floor provide much finer and more accurate topographic data for the deep ocean floor with a spatial resolution (as distinct from a vertical resolution) of at least 100 meters in 5000- Fig. 1. Satellite-derived gravity field (gray) Sandwell[ et al., 2014] and multibeam echo meter water depths. However, only 10%–15% of sounder (color) data were used to produce these maps of the MH370 search area in the the ocean basins have been mapped using mul- southeastern Indian Ocean. The relief models are shown in Sun-illuminated (shaded tibeam echo sounders [Weatherall et al., 2015]. relief) mode. The inset map shows the MH370 search area that was mapped with multi- This technique also records acoustic back- beam echo sounding (shown in red). This map highlights the Southeast Indian Ridge scatter from the ocean floor, which can be used (SEIR) and the Kerguelen Plateau, and it includes estimated spreading rates of the SEIR to distinguish between hard rock and soft sedi- [Argus et al., 2011], lines delineating regions of approximately equal age (isochrons) ment. Such fundamental spatial information is [Müller et al., 2008], and interpretations of SEIR segments (I–VII) [Small et al., 1999]. Other essential for characterizing the physical fea- abbreviations are AAD, Australian-Antarctic Discordance; CIR, Central Indian Ridge; RTJ, tures of the ocean floor, for making inferences Rodriguez Triple Junction; SWIR, Southwest Indian Ridge; WA, Western Australia. The on geological and oceanographic processes, and larger map shows details of the ocean depth mapping effort using multibeam echo for identifying the habitats of species that live sounder bathymetry data. Locations of Deep Sea Drilling Project (Leg 26) and Ocean on the ocean floor. Drilling Program (Legs 121 and 183) Sites 255, 752 to 755, 1141, and 1142 are also indicated, as are the locations of Figures 2, 3, and 4. Figure 4 can be found on Eos.org A Complex Region (http://bit.ly/Eos_MH370). Beyond the continental margins, toward the open sea, the floor of the Indian Ocean is a complex mosaic of normal oceanic crust (not roughly 2500 kilometers from the eastern flank of Batavia associated with hot spots and other anomalies), submarine Seamount to the Geelvinck Fracture Zone (Figure 1). Air- plateaus and ridges, seamounts, sea knolls, and microcon- craft debris found along the shores of the western Indian tinents. Various processes, including seafloor spreading Ocean were consistent with drift modeling that indicates (including ridge jumps), flood and hot spot magmatism, that the aircraft entered the sea in the search area (see and tectonism, produce a variety of features. http:// bit . ly/ MH370 - search). The MH370 search area includes all of the major elements The data set that emerged from this search effort con- of the mosaic, and it covers water depths between 635 and stitutes the largest high-resolution multibeam echo 6300 meters (Figure 1). The search teams mapped most of sounder mapping effort for the Indian Ocean, covering an the area with a 30-kilohertz multibeam echo sounder sys- area about the size of New Zealand. Previous ocean floor tem (Kongsberg EM302, M/V Fugro Equator), and they

26 // Eos May 2017 Fig. 2. Three- dimensional model looking east of the rifted southern flank The southern flank of Broken Ridge, known as the of Broken Ridge (northern part of the rift valley) along the Diamantina Diamantina Escarpment, documents the rifting, plung- Escarpment. Slopes commonly exceed 10°, and they increase to more ing more than 5100 meters from its crest (638 meters of than 35° along the margins of the Diamantina Trench. Large- scale water depth) into a deep trough (5800 meters of water ocean floor features include escarpments (as much as 1200 meters depth). This rifted flank includes escarpments rising high), detachment blocks, grabens, and areas of planar floor within the more than 1000 meters above the ocean floor, slopes as trench as wide as 10 kilometers. High backscatter intensity and angular steep as 67°, and fault blocks about 12 × 25 kilometers in morphology indicate that bedrock is exposed, in a few places at and size and rising more than 1200 meters above their base near the top of the ridge and on the flank down to depths of about 1350 (Figure 2). meters. Parallel west-southwest to east-northeast lineations on some The new multibeam echo sounder data, integrated with scarps, extending to water depths of about 2400 meters, most likely preexisting seismic reflection and drilling data, illuminate represent exposed, steeply dipping bedding planes. Mass wasting, a exposed igneous basement rock, prerift sedimentary sec- downslope movement of loose rocks and sediment during and after the tions, and overlying sediment that accumulated on the rifting process, has incised the escarpment, and significant sediment has ocean floor during (hemipelagic sediment) and after accumulated in the grabens and at the bottom of the Diamantina Trench (pelagic sediment) rifting. (see Figure 1 for location). The morphology and seismic stratigraphy of the Dia- mantina Escarpment indicate that the mode of rifting resembled an orthogonal rift model, in which faults develop parallel to the axis of spreading. Between the mapped much smaller areas with 12-kilohertz systems, faults, a series of elongated blocks of crustal material, gra- which can reach the deeper ocean floor (Kongsberg EM122, bens, step down into a deep trough and abut the spreading M/V Fugro Supporter; Reson SeaBat 8150, Chinese PLA Navy ridge volcanics [Karner and Driscoll, 1993]. ship Zhu Kezhen). Here we highlight three examples from this shipboard Seafloor Erosion multibeam echo sounder data set that are helping to illu- North of its rifted southern flank, Broken Ridge generally minate the geologic development of this portion of the has subtle relief, with igneous basement rocks overlain by Indian Ocean.

Submarine Plateau Rifting and Breakup For an additional image of seafloor in the Broken Ridge and the Kerguelen Plateau formed mostly as search area, view this article on Eos.org: a contiguous large igneous province in Cretaceous time http://bit.ly/Eos_MH370. For more about [Coffin et al., 2000]. They subsequently experienced rifting and were eventually separated by seafloor spreading along how much of the seafloor under commercial the Southeast Indian Ridge (SEIR) 43 million years ago flight paths remains unmapped, see page 12. [Mutter and Cande, 1983].

Earth & Space Science News Eos.org // 27 Handout/Getty Images News/ Getty Images

A U.S. Navy helicopter carries supplies from the USNS Cesar Chavez to the HMAS Success in April 2014, during the search in the Indian Ocean for Malaysia Airlines Flight MH370.

sedimentary rock and pelagic sediment [e.g., Coffin et al., meters northeast of the crest of Broken Ridge (Fig- 2000]. In places, slides and debris flows have reworked ure 3). Numerous crosscutting retrogressive slides sediment downslope. (where the collapsing area extends progressively higher A large depression, about 90 kilometers in diameter up the slope) and debris flows dissect the flanks of the and with about 500 meters of relief, lies some 70 kilo- depression, recording episodes of sediment flow, with

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28 // Eos May 2017 Gaining Useful Knowledge from a Tragic Event The new multibeam echo sounder data highlight the topographic complexity of the ocean floor and provided a framework for deploying deepwater instruments in the search for MH370 wreckage. The data also reveal details of the tectonic, sedimentary, and volcanic processes that formed this region of the ocean. This effort demonstrates the breadth and depth of knowledge that will be gained as the remaining 85% to 90% of the global ocean is mapped at similar resolution.

Acknowledgments We thank the Geoscience Australia team, especially Tanya Whiteway and Maggie Tran, for project management; Maggie Tran, Justy Siwabessy, Michele Spinoccia, Jonah Sullivan, and Jonathan Weales for data processing and mapping; and Silvio Mezzomo and David Arnold for the figures. We are thankful for insightful reviews by Scott Nichol and Ron Hackney of Geoscience Austrialia and two Fig. 3. The differences in resolution between multibeam andsatellite- derived bathyme- anonymous reviewers. The search for MH370 try data for the northern flank of Broken Ridge are apparent here. Numerous mass was managed by the Australian Transport wasting features are evident, including slides and debris flows (delineated by their head Safety Bureau and the Joint Agency Coordina- scarps) that crosscut and run out as debris fans into the large semicircular depression tion Centre for the Malaysian government. (see Figure 1 for location). We thank the Fugro Survey Pty. Ltd. team from Perth, Australia, and the masters and crews of M/V Fugro Equator, M/V Fugro Sup- slide scarps as much as 180 meters high and 10 kilome- porter, and Zhu Kezhen for shipboard multibeam echo ters wide and debris fans more than 150 kilometers sounder data acquisition. long. References Tectonic Spreading Fabric Argus, D. F., R. G. Gordon, and C. DeMets (2011), Geologically current motion of 56 plates relative to the no net rotation reference frame, Geochem. Geophys. Geosyst., 12, South of Broken Ridge, normal oceanic crust of the Q11001, https:// doi . org/ 10 . 1029/ 2011GC003751. Australian-Antarctic Basin has formed along the SEIR at Coffin, M. F., F. A. Frey, and P. J. Wallace (2000), Proceedings of the Ocean Drilling Pro- intermediate spreading rates of 59–75 millimeters per year gram, Initial Reports, vol. 183, 101 pp., Ocean Drill. Program, College Station, Texas. Copley, J. T. (2014), Just how little do we know about the ocean floor?, Conversation, [Small et al., 1999; Müller et al., 2008]. The shipboard multi- 9 Oct. 2014, http:// theconversation . com/ just - how - little - do - we - know - about - the - ocean beam echo sounder data swath traverses a region of crust -floor - 32751. north of the SEIR that is some 10 million to 40 million Karner, G. D., and N. W. Driscoll (1993), Rift flank topography and extensional basin archi- tecture: Formation of Broken Ridge, southeast Indian Ocean, An. Acad. Bras. Cienc., years old, obliquely cutting across tectonic seafloor spread- 65, suppl. 2, 263–294. ing fabric consisting of elongated abyssal ridges and frac- Müller, R. D., M. Sdrolias, C. Gaina, and W. R. Roest (2008), Age, spreading rates, and spreading asymmetry of the world’s ocean crust, Geochem. Geophys. Geosyst., 9, ture zones (Figure 1). Q04006, https:// doi . org/ 10 . 1029/ 2007GC001743. Oceanic crust in this region, which lies in water Mutter, J. C., and S. C. Cande (1983), The early opening between Broken Ridge and the depths of 2200 to 5000 meters, is characterized by SEIR Kerguelen Plateau, Earth Planet. Sci. Lett., 65, 369–376, https:// doi . org/ 10 . 1016/ 0012 -821X(83) 90174 - 7. and paleo-SEIR segments some 200 to 500 kilometers Sandwell, D. T., R. D. Müller, and W. H. F. Smith (2014), New global marine gravity model long (Figure 1) [Small et al., 1999]. In the search area, from Cryo- Sat- 2 and Jason- 1 reveals buried tectonic structure, Science, 346, 65–67, fracture zone valleys are as much as 900 meters deep https:// doi . org/ 10 . 1126/ science . 1258213. Small, C., J. R. Cochran, J.-C. Sempéré, and D. Christie (1999), The structure and segmen- and 12 kilometers wide. The abyssal ridges have as tation of the Southeast Indian Ridge, Mar. Geol., 161, 1–12, https:// doi . org/ 1 0 . 1016/ S0025 much as 200 meters of relief and are more than -3227(99) 00051 - 1. 70 kilometers long (Figure 4 at http://bit.ly/Eos Weatherall, P., K. M. Marks, and M. Jakobsson (2015), A new digital bathymetric model of the world’s oceans, Earth Space Sci., 2, 331–345, https:// doi . org/ 10 . 1002/ _MH370). 2015EA000107. Discontinuities along the paleo-SEIR not associated with transform faults and more than 150 sea knolls and Author Information seamounts are also common. Volcanoes occur in isolation Kim Picard (email: [email protected]) and Brendan Brooke, and in chains, forming semiconcentric structures, some Geoscience Australia, Canberra, ACT; and Millard F. Coffin, as high as 1500 meters, with diameters of about 500 Institute for Marine and Antarctic Studies, University of Tasma- meters to more than 15 kilometers and slopes of about 10° nia, Hobart, Australia; and Woods Hole Oceanographic Institu- to 30°. tion, Woods Hole, Mass.

Earth & Space Science News Eos.org // 29 SYNTHESIZING OUR UNDERSTANDING OF EARTH’S DEEP CARBON By Marie Edmonds and Craig Manning

Volcanoes bring carbon-containing gases from Earth’s depths to the surface. Volca- nologists use aerial vehicles to sample these gas plumes.

30 // Eos May 2017 The Deep Carbon Observatory is entering a SYNTHESIZING OUR new phase in which it will integrate 10 years of discoveries into an overarching model to beneﬁ t UNDERSTANDING OF the scientiﬁ c community and a wider public.

arbon is one of the most important elements much carbon resides in the deep Earth, its form, and how it on our planet; its distribution on and in Earth moves between deep and shallow reservoirs. affects the global climate system, the ori- Addressing these questions has been the core research gin and evolution of life, and the types and goal of the Deep Carbon Observatory (DCO) program. Deep availability of energy resources. The geologi- carbon science has emerged as a new scientific discipline, cal cycling of carbon, driven by plate tecton- aimed at understanding the quantities, movements, forms, ics over long timescales, is the main factor influencing the and origins of carbon in Earth’s crust, mantle, and core, Csize of Earth’s shallow carbon reservoirs. Until recently, where we now know that more than 90% of Earth’s carbon however, we had only a fragmented understanding of how resides. The program has amassed 7 years’ worth of dis- Trail by Fire Team Trail

Earth & Space Science News Eos.org // 31

SA 3.0 3.0 SA BY- Stapanov Alexander, CC Alexander, Stapanov (http://bit.ly/ccbysa3-0)

Understanding how carbon cycles deep in Earth’s crust, mantle, and core may inform scientists about how this element underpins a range of terrestrial processes, including diamond formation. Shown here is an aerial view of the Udachnaya pipe deposit diamond mine in Sakha Republic, Russia.

coveries about carbon in Earth’s depths. Over the next carbon-bearing minerals on Earth have histories that 3 years, the program will integrate these discoveries into closely mirror such major events in Earth’s history as the an overarching model of carbon in Earth and create lega- Great Oxidation Event, when biologically mediated free cies for the scientific community and wider public. oxygen first appeared in our atmosphere, opening the way for the aerobic organisms we know today [Hazen et al., DCO’s First 7 Years: A New Understanding 2013b]. of Deep Carbon Recent research has extended the known limits to DCO research encompasses many related topics. How do microbial life; one study showed that microbes thrive as subduction and volcanic and tectonic degassing cause car- deep as 2.5 kilometers in the oceanic crust [Inagaki et al., bon to cycle into and out of the mantle? What is the extent 2015]. Another study has identified unique microbial and diversity of the deep microbial biosphere? What forms organisms that thrive as deep as 2 kilometers beneath the and structures do carbon- bearing melts and minerals take surface under the hot, highly saline conditions associated in the mantle and core? What is the nature of deep sources with the hydraulic fracturing of shale [Daly et al., 2016]. of such carbon- based fluids as methane and higher hydro- We’ve also improved our understanding of the volcanic carbons, and what processes control their formation output of carbon into our atmosphere: Novel instrument [Hazen et al., 2013a]? networks reveal that volcanic flux of carbon dioxide is One highlight of our research is the discovery of what twice what researchers previously thought [Burton et al., happens when carbon is carried from Earth’s crust into the 2013]. mantle through subduction. For example, diamonds, which Other studies measure the fluxes of reduced carbon (e.g., can contain geochemical signatures of organic material methane) in diverse crustal environments. Next- from Earth’s surface, may form as a result of pH shifts in generation mass spectrometry allows scientists to pre- mantle fluids [Sverjensky and Huang, 2015]. Deeply sub- cisely identify the isotopic makeup of methane molecules ducted carbonate minerals transform to a novel structure (isotopologues) to trace them back to their sources in the that features carbon in tetrahedral coordination with oxy- crust and mantle [Young et al., 2016]. Still other studies gen, rather than the triangular coordination more typical have led to the discovery of “ancient water,” more than a of minerals near the surface [Boulard et al., 2015]. billion years old. This discovery provides evidence for the Closer to the surface, the geosphere and biosphere show existence of early crustal environments perhaps capable of a complex linked evolution. The diversity and ecology of harboring life [Holland et al., 2013].

32 // Eos May 2017 Synthesizing a Decade of DCO Science As the DCO completes its first decade of focused research, its emphasis is shifting toward scientific synthesis. For example, our workshops now center around unifying themes. Special publications and review articles will contain the underpinning science and discoveries that have emerged from the DCO and guide future scientific endeavors. An important synthesis effort is the development of models and visualizations. We are developing models over a range of spatial and temporal scales to describe carbon mineralogy, carbon partitioning, fluxes between carbon reservoirs, and the extent and diversity of microbial life. Already, new models of the processes by which subduction causes Earth’s mantle to take in and release gas

suggest that subducting slabs transport car- Maarten de Moor bon more efficiently toward Earth’s surface DCO researcher at Poás volcano, Costa Rica, using a multigas instrument [Aiuppa et al., than previously thought [Kelemen and Man- 2007] to measure carbon to sulfur molar ratios in the gas plume. ning, 2015]. Scientists have attempted to extend such analyses back in time to the early Earth [Dasgupta, 2013]. Boulard, E., et al. (2015), Tetrahedrally coordinated carbonates in Earth’s lower mantle, Models of mantle melting beneath mid-ocean ridges Nat. Commun., 6, 6311, https:// doi . org/ 10 . 1038/ ncomms7311. [Rosenthal et al., 2015; Behn and Grove, 2015] show that small Burton, M. R., G. M. Sawyer, and D. Granieri (2013), Deep carbon emissions from volca- amounts of carbonated melts and their reactive flow play noes, Rev. Mineral. Geochem., 75(1), 323–354, https:// doi . org/ 10 . 2138/ rmg . 2013 . 75 . 11. Daly, R. A., et al. (2016), Microbial metabolisms in a 2.5- km- deep ecosystem created critical roles in mantle dynamics [Keller and Katz, 2016]. by hydraulic fracturing in shales, Nat. Microbiol., 1, 16146, https:// doi . org/ 10 . 1038/ Another key modeling effort focuses on the nature of nmicrobiol . 2016 . 146. carbon-bearing fluids by integrating existing thermody- Dasgupta, R. (2013), Ingassing, storage, and outgassing of terrestrial carbon through geologic time, Rev. Mineral. Geochem., 75, 183–229, https:// doi . org/ 10 . 2138/ rmg . 2013 namic models of magmas in the crust (MELTS; http://melts .75.7. .ofm - research . org) [Ghiorso and Sack, 1995] and fluids in Ghiorso, M., and R. Sack (1995), Chemical mass transfer in magmatic processes IV. A revised and internally consistent thermodynamic model for the interpolation and the mantle (Deep Earth Water (DEW); http:// bit . ly/ DEW extrapolation of liquid- solid equilibria in magmatic systems at elevated temperatures -model) [Sverjensky et al., 2014a, 2014b] to form a frame- and pressures, Contrib. Mineral. Petrol., 119(2–3), 197–212, https:// doi . org/ 10 . 1007/ BF00307281. work for modeling mass transfer of carbon and other ele- Hazen, R., A. Jones, and J. Baross (Eds.) (2013a), Carbon in Earth, Rev. Mineral. Geo- ments. chem., 75, 698 pp. Hazen, R. M., et al. (2013b), Carbon mineral evolution, Rev. Mineral. Geochem., 75, Reaching a Broader Audience 79–107, https:// doi . org/ 10 . 2138/ rmg . 2013 . 75. 4. Holland, G., et al. (2013), Deep fracture fluids isolated in the crust since the Precambrian DCO scientists are striving to share what they have learned era, Nature, 497(7449), 357–360, https:// doi . org/ 10 . 1038/ nature12127. about the global deep carbon cycle with fellow scientists, Inagaki, F., et al. (2015), Exploring deep microbial life in coal- bearing sediment down to future students, and an interested public. We will share ~2.5 km below the ocean floor, Science, 349(6246), 420–424, https:// doi . org/ 10 . 1126/ science . aaa6882. many of the findings through peer- reviewed publications, Kelemen, P. B., and C. E. Manning (2015), Reevaluating carbon fluxes in subduction but DCO is also dedicating resources to creating films, zones, what goes down, mostly comes up, Proc. Natl. Acad. Sci. U. S. A., 112(30), infographics, and books. For more information, review E3997–E4006, https:// doi . org/ 10 . 1073/ pnas . 1507889112. Keller, T., and R. F. Katz (2016), The role of volatiles in reactive melt transport in the asthe- DCO’s midterm report (see http:// bit . ly/ DCO - Midterm) on nosphere, J. Petrol., 57(6), 1073–1108, https:// doi . org/ 10 . 1093/ petrology/ egw030. the observatory’s website (https:// deepcarbon . net) and Rosenthal, A., E. Hauri, and M. Hirschmann (2015), Experimental determination of C, F, follow DCO on Twitter (@deepcarb) and Facebook (http:// and H partitioning between mantle minerals and carbonated basalt, CO2/Ba and CO2/ Nb systematics of partial melting, and the CO2 contents of basaltic source regions, bit . ly/ DCO - FB). Earth Planet. Sci. Lett., 412, 77–87, https:// doi . org/ 10 . 1016/ j . epsl . 2014 . 11 . 044. Sverjensky, D. A., and F. Huang (2015), Diamond formation due to a pH drop during fluid- Acknowledgments rock interactions, Nat. Commun., 6, 8702, https:// doi . org/ 10 . 1038/ ncomms9702. Sverjensky, D. A., V. Stagno, and F. Huang (2014a), Important role for organic carbon in DCO distributes seed funding from the Alfred P. Sloan subduction-zone fluids in the deep carbon cycle, Nat. Geosci., 7, 909–913, https:// doi Foundation via four research communities to leverage sci- .org/ 10 . 1038/ ngeo2291. entific endeavors addressing DCO’s goals. Robert Hazen, Sverjensky, D. A., B. Harrison, and D. Azzolini (2014b), Water in the deep Earth: The dielectric constant and the solubilities of quartz and corundum to 60 kb and 1200° C, Craig Schiffries, Katie Pratt, and Darlene Trew Crist pro- Geochim. Cosmochim. Acta, 129, 125–145, https:// doi . org/ 10 . 1016/ j . gca . 2013 . 12 . 019. vided valuable input. Young, E. D., et al. (2016), A large- radius high- mass- resolution multiple- collector isotope ratio mass spectrometer for analysis of rare isotopologues of O2, N2, CH4 and other gases, Int. J. Mass Spectrom., 401, 1–10, https:// doi . org/ 10 . 1016/ j. ijms . 2016 . 01 . 006. References Aiuppa, A., et al. (2007), Forecasting Etna eruptions by real-time observation of Author Information volcanic gas composition, Geology, 35(12), 1115–1118, https:// doi . org/ 10 . 1130/ G24149A. 1. Marie Edmonds (email: me201@ cam . ac . uk), Earth Sciences Behn, M. D., and T. L. Grove (2015), Melting systematics in mid- ocean ridge basalts: Department, University of Cambridge, Cambridge, U.K.; and Application of a plagioclase-spinel melting model to global variations in major element Craig Manning, Department of Earth and Space Sciences, Uni- chemistry and crustal thickness, J. Geophys. Res. Solid Earth, 120(7), 4863–4886, https:// doi . org/ 10 . 1002/ 2015JB011885. versity of California, Los Angeles

Earth & Space Science News Eos.org // 33 AGU NEWS

delight, some 250 conference attendees regis- Getting to Fair: Recognizing tered for the workshop. Implicit Bias and Easing Its Impact Tactics Against Implicit Bias It was heartening to see such widespread interest in this important topic at the workshop. Below, we provide some additional information, starting with the following six tactics to reduce the impact of implicit bias in the geosciences: • Build awareness of the scientific contributions made by women colleagues. Have they been nominated for awards for which they are qualified? Visit the AGU Honors website (http:// bit . ly/ aguhonors) and see the lists of awardees posted there; then think hard of women colleagues whose names are missing. • Notice whether women in meetings are interrupted or their ideas are heard respect- fully. Research demonstrates that when hink of a nurse, and whom do you pic- or to maintain a particular status quo. women in a mixed group speak for more than ture? Likely, it’s a woman. Think of a Implicit thinking that makes use of prepro- about 25% of the time, both men and women T scientist, and whom do you picture? grammed schemas and assumptions is nec- perceive that “women did all the talking” (see Likely, it’s a man. This may not seem like a essary to get through the day. We can’t stop http:// bit . ly/ TalkBias). very big deal, but under many circum- and think when a lion is racing toward us, “Is • Look for telltale signs of bias in nomina- stances—for instance, when evaluating some- this one of the nice lions?” Folks who do that tion and support letters. Many studies show one’s job performance or an application for are gone from the gene pool! We don’t face that letters of nomination and recommenda- honors or graduate school—social mores of rampaging lions much anymore, yet the sur- tion written for men tend to be to be longer, which we are unaware may surface to direct vival instincts we acquired in those bygone have more superlatives, and directly address our conscious thought. A number of studies eras are still part of our nature. It therefore the curriculum vitae. Letters written for have shown that conscious, willful thinking is takes some effort to combat implicit bias—in women, on the other hand, tend to be shorter, only the tip of the iceberg as our brains pro- other words, to be fair. have more personal references (e.g., to marital cess information leading to a decision. Around Dozens of studies have revealed the effects status, motherhood, “nice” qualities), and 2% of brain activity is conscious; the rest is of implicit bias on evaluation outcomes. As have considerably less written about scholas- below the level of consciousness, or implicit, members of AGU’s Honors and Recognition tic achievements and qualifications. often leading to unintended consequences. Committee, we see those effects in the form We write letters for men with more “agen- Within a given cultural group, members of fewer women being nominated for or win- tic” terms (i.e., agents of effectiveness) and share the same implicit thoughts and ning scientific awards and fewer being letters for women with more “communal” assumptions that are absorbed through life selected as Fellows. On the other hand, we terms (gets along with people). It’s nice to be experience. If there is a bias in favor of women see disproportionately more women receiving described as agreeable and pleasant, but agen- in the United States, nearly all of us in the service and teaching awards. Among other tic attributes get us the job, get us noticed, get country share it, without realizing it. If the impacts, we see disproportionately few peo- us nominated for awards (see http:// bit . ly/ bias is negative, we share that, too. ple of color and women working in our scien- recLetters). These implicit assumptions slant whom we tific fields, and fewer people from outside the Most recently, Kuheli Dutt of Lamont- nominate, whom we listen to, how qualified United States nominated for or winning Doherty Earth Observatory and her colleagues we think someone is for a job, and whether awards. examined 1224 letters of recommendation for their qualifications seem to fit our ideas about postdoctoral positions in the geosciences and the “ideal worker.” Psychologist Virginia Val- Avoiding the Automatic found that women were only half as likely as ian of Hunter College calls this slight bias at If this is how our brains work, what can we do men to have an excellent letter written for each career step “the mountain made of to bypass this automatic mechanism? their applications (see http:// bit . ly/ LetterBias). molehills” that impedes women’s careers (see Research into solutions is ongoing and focuses If letters for a nominee are clearly biased in http:// bit . ly/ unsaid - beliefs). For AGU publica- for now on promoting awareness that this is this manner, the AGU Honors Committee can tions, it leads to fewer women being suggested how our brains work, that this seemingly ask that they be rewritten. A set of guidelines to review journal articles, a necessary activity small bias has a negative impact on our col- for writing good letters of nomination and of for career advancement in science, technol- leagues in certain underrepresented groups, support and recommendation is provided on ogy, engineering, and mathematics (STEM) and that taking more time (not feeling time the AGU Honors website. fields (see http:// bit . ly/ too - few - women - refs). pressure) helps to reduce this barrier. • Ensure that each section and focus group A workshop hosted by our committee at the nomination committee has a canvassing com- From Survival to Evaluation 2016 AGU Fall Meeting aimed to raise aware- mittee charged with finding worthy nominees It’s important to emphasize that we are not ness about implicit bias in evaluations. We and colleagues to nominate them. making biased decisions on purpose. Nor do had hoped to reach at least 40 AGU members • Provide each selection committee (and we make them to be mean or discriminatory with our “Getting to Fair” event. To our any committee evaluating applicants for per-

34 // Eos May 2017 AGU NEWS

formance) with a clearly written set of criteria for the award/selection before the nomina- Radio Science and Space Weather tions are submitted for review. We have all witnessed the phenomenon whereby one year Now Available on IEEE Xplore we select a colleague on the basis of number of publications, and then the following year this evaluation criterion is less important and the letters of reference are elevated in impor- Thousands of IEEE Xplore tance. The committee’s criteria should be con- users worldwide will now be able sistent, clearly articulated, and arrived at by to find more than 7000 articles consensus. from these two journals. Within • Step up, women colleagues, and nomi- this database of more than 4000 nate other women! Women are less likely to publication titles, users can per- submit nominations (for men or women). form full-text searches and use Women need to be in the game before every- tools that refine results by title, one plays fair. author, affiliation, publication, publication date, and more. Including Non-Majority Voices Brooks Hanson, director of In the long run, addressing inequity will AGU Publications, noted, “Now require changing the culture of the system that these articles are more dis- that trains new scientists. Some 65 academic coverable by the broader engi- institutions in the United States have received neering community, we are ADVANCE grants from the National Science increasing the likelihood they Users of the IEEE Xplore database can now find articles from AGU’s Foundation. These are designed to increase will be read and cited. And we Radio Science and Space Weather journals. the number of STEM women on the faculty by also hope that this cross- addressing ingrained, often unchallenged, pollinates new relationships gender-biased procedures, policies, and pro- wo of AGU’s journals, Radio Science and between engineers and Earth and space sci- cesses that determine who is on our faculty. Space Weather, are now indexed in IEEE entists.” In the United States, many academic insti- T Xplore, a digital library of scholarly tutions require that some “nonmajority” per- research focused on the topics of computer son serve on each search committee for new science and engineering (http:// bit . ly/ IEEE By Jamie Liu (email: jliu@ agu . org), Marketing faculty as well as on other selection commit- -Xplore). Manager, AGU tees. This process has backfired by overbur- dening women and faculty of color with extra service work. North Dakota State University, following the lead of the University of California, Irvine, Read it first on . and many other ADVANCE institutions, has created a “male advocates and allies” program, wherein men learn about implicit bias and how to combat it and serve as the Articles are published on Eos.org before they appear in the magazine. “minority voice” on committees. AGU Honors committees could benefit by having at least Visit http://eos.org daily for the latest news and perspectives. one bias awareness–trained male advocate on each committee to help members learn about implicit bias and its impact and develop strat- • Explaining Unexpected Twists in the Sun’s Magnetic Field egies to minimize that impact. http://bit.ly/EOS_Magnetic_Field

By Mary Anne Holmes (email: agu _ unionhonors • Why Do Great Earthquakes Follow Each Other at Subduction Zones? @ agu . org), Sam Mukasa (chair), and Donald Schwert, Honors and Recognition Committee, http://bit.ly/EOS_Subduction_Zone AGU • What Regions Are Most at Risk for Ice Loss in East Antarctica? Read more articles on Eos.org that http://bit.ly/EOS_Ice_Loss_Risk address gender bias: http://bit.ly/Eos_women-scientists http://bit.ly/Eos_cryosphere-diversity • AGU Board Vacancy Filled, Council Leaders Chosen http://bit.ly/Eos_support-networks http://bit.ly/EOS_Council http://bit.ly/Eos_gender-parity

Earth & Space Science News Eos.org // 35 AGU NEWS

Keith Jennings, University of Colorado, Boulder, Assess- Outstanding Student Paper Awards ing the climate sensitivity of cold content and snowmelt in seasonal alpine and subalpine snowpacks Emily Kane, University of California, Irvine, Measuring short term velocity changes of Kangilerngata Sermia, West The following AGU members received Outstanding Student Paper Awards at the 2016 Fall Meeting in Greenland, using a gamma portable radar interferometer San Francisco, Calif. Winners have individual pages on AGU’s website (see http://bit.ly/Eos_OSPA). Christian Kienholz, University of Alaska Fairbanks, Inte- grating in- situ observations, remote sensing and modeling to Atmospheric and Space Electricity calibration, and initial evaluation of a high- density CO2 sur- constrain the mass balance evolution of Black Rapids Glacier, face network Alaska, 1980–2015–2100 Coordinator: Morris Cohen Jennifer Walker, California Institute of Technology, Onset Aaron Mohammed, University of Calgary, Vadose zone Gregory Bowers, University of California, Santa Cruz, TGF and withdrawal of the large- scale South Asian monsoon: A dynamics governing snowmelt infiltration and groundwater ground observations from a winter thunderstorm in Japan: dynamical definition using change point detection recharge in a seasonally frozen, semi- arid landscape First ground observation of a multipulse TGF & evidence of Simon Wild, University of Birmingham, Extra- tropical Kira Olsen, Columbia University in the City of New York, neutron production from a TGF cyclones and windstorms in seasonal prediction models Regional and local glacial-earthquake patterns in Green- Vanna Chmielewski, Texas Tech University, An analysis of Brandon Wolding, Colorado State University, Destabiliza- land small changes in environment which resulted in diverse tion of the Madden–Julian Oscillation in present and future Kevin Schiele, Ulster University, Offshore–onshore cor- charge structures on 4 June 2012 in West Texas climates relations refining the glacial history of western Ireland Xiyue Zhang, California Institute of Technology, Arctic Atmospheric Sciences mixed- phase clouds in large- eddy simulations and a mixed- Earth and Planetary Surface Processes layer model Coordinators: Shannon Capps, Ross Salawitch Coordinator: Roman DiBiase

Rachel Elizabeth Bartlett, University of Edinburgh, Do dif- Biogeosciences William Jesse Hahm, University of California, Berkeley, ferences in future sulfate emission pathways matter for near- Ecohydrological consequences of Critical Zone structure in Coordinators: Noel Aloysious, Justin Dodd, Maggie Lau, term climate? A case study for the Asian monsoon the Franciscan Formation, northern California Coast Sue Natali, Kunwar Singh Di Chen, State University of New York at Albany, Depen- Ranges dence of estimated precipitation frequency and intensity on Jotautas Baronas, University of Southern California, Mix- Alexander Horton, Cardiff University, Modification of river data resolution ing as a driver of temporal variations in river hydrochemistry: meandering caused by tropical deforestation along the Hong Chen, University of Colorado, Boulder, Using air- Concentration- runoff dynamics in the Andes- Amazon Kinabatangan River, Borneo craft observations to improve passive remote sensing of Zichong Chen, University of Minnesota, Twin Cities, Parti- Katherine Lininger, Colorado State University, Geomor- clouds in the Arctic tioning N2 O emissions within the US corn belt using an phic controls on floodplain organic carbon storage in sedi- Eliza Dawson, University of Washington, Variability of the inverse modeling approach ment along five rivers in interior Alaska Inter-Tropical Convergence Zone related to changes in inter- Amber Churchill, University of Colorado, Boulder, Alpine Virginia Marcon, Pennsylvania State University, Evaluat- hemispheric dust load plant community controls on ecosystem N pools under the influ- ing the effect of lithology on porosity development in ridge- Amanda Giang, Massachusetts Institute of Technology, ence of N deposition using an enriched 15N tracer experiment tops in the Appalachian Piedmont Implications of climate variability for monitoring the effec- Alison Hoyt, Massachusetts Institute of Technology, Meth- Ryan Sincavage, Vanderbilt University, Patterns of down- tiveness of global mercury policy ane oxidation in a tropical peatland stream fining and facies change reflecting differing modes of Alexander Hegedus, University of Michigan, Simulating Malcolm Itter, Michigan State University, A model- based mid-Holocene sediment disperal across the Ganges- 3D spacecraft constellations for low frequency radio imaging approach to infer shifts in regional fire regimes over time Brahmaputra- Meghna Delta Stephanie Henderson, Colorado State University, The using sediment charcoal records Alexandra Skrivanek, University of Florida, Evidence for extratropical influence of the Madden–Julian Oscillation on Yanlan Liu, Duke University, Increasing atmospheric tectonism based on differential uplift of the Falmouth Forma- wintertime blocking humidity and CO2 concentration alleviate forest mortality risk tion of Jamaica Huancui Hu, University of Illinois at Urbana- Champaign, Lauren Lowman, Duke University, Predicting phenologic Introducing water tracers in the Noah- MP land surface model response to water stress and implications for carbon uptake Earth and Space Science Informatics Xiaomeng Jin, Columbia University in the City of New across the Southeast U.S. Coordinators: Mohamed Aly, Anita Dewaard, York, Evaluating a space- based indicator of surface ozone Lynsay Spafford, Saint Francis Xavier University, Sudhir Shrestha, Brad Zavodsky sensitivity to emissions of NOx vs. NMVOC over major north- Temporally- resolved study of atmosphere- lake net CO2 ern midlatitude source regions exchange at Lochaber Lake, Nova Scotia, Canada Ankit Rai, University of Illinois at Urbana-Champaign, Richie Kaur, University of California, Davis, Aqueous reac- Begum D. Topcuoglu, University of Massachusetts, Meth- Identifying green infrastructure from social media and tions of triplet excited states with allylic compounds anogenic hydrogen syntrophy among thermophiles: A model crowdsourcing—An image based machine-learning Feiyu Lu, University of Wisconsin–Madison, Understand- of metabolism, adaptation and survival in the subsurface approach ing the control of extratropical atmospheric variability on Ellen Ward, Stanford University, Strategy to conduct quan- ENSO using regional coupled data assimilation titative ecohydrologic analysis of a UNESCO World Heritage Education Erin McDuffie, University of Colorado, Boulder, The win- Site: The Peace- Athabasca Delta, Canada Coordinator: Stacie Bender tertime fate of N2 O5: Observations and box model analysis for the 2015 WINTER Aircraft Campaign Cryosphere Sean Czarnecki, Angelo State University, New mapping in Elin McIlhattan, University of Wisconsin–Madison, Every the Sand Springs Range of western Nevada clarifies and con- Coordinators: Ellyn Enderlin, Dan McGrath, Lucas Zoet day is a snow day: Leveraging A- Train observations to evalu- strains regional deformation sequences of the Lining- ate Arctic liquid containing cloud processes in the Commu- Cenlin He, University of California, Los Angeles, A Fencemaker thrust belt nity Earth System Model physically- based parameterization for BC- snow interaction Yi- Ling Hwong, University of New South Wales, What Alexis Shusterman, University of California, Berkeley, The with application to snow albedo reduction over the Tibetan makes you tick? An empirical study of space science related Berkeley Atmospheric CO2 Observation Network: Design, Plateau social media communications using machine learning

36 // Eos May 2017 AGU NEWS

Geodesy Bernardo Carvalho Trindade, Cornell University, Time Ryan J. McCarty, Stanford University, NMR technique for evolving multi-city dependencies and robustness tradeoffs determining transition metal cation distribution at low con- Coordinators: Yuning Fu, Emily Montgomery- Brown, for risk-based portfolios of conservation, transfers, and centrations demonstrated using periclase (MgO) and CaO Bob Wang cooperative water supply infrastructure development path- Roberto Emanuele Rizzo, University of Aberdeen, Riding Mary Grace Bato, Institut des Sciences de la Terre, Vol- ways the right wavelet: Detecting fracture and fault orientation cano deformation and eruption forecasting using data assim- Levon Demirdjian, University of California, Los Angeles, scale transitions using Morlet wavelets ilation: Building the strategy Improving the statistical modeling of the TRMM Extreme Pre- Priyamvada Nanjundiah, Nanyang Technological Univer- cipitation Monitoring System Natural Hazards sity, Tectonic and geomorphic setting of the Pamir Plateau— Johanna Engstrom, University of Florida, Hydropower in Coordinators: Naresh Devineni, Phu Nguyen, Yadu Pokhrel, Insights from InSAR, seismic and optical data for the 2015 southeastern United States—A hydroclimatological perspec- Armin Sorooshian Mw 7.2 Darwas- Karakoram earthquake tive Talib Oliver, University of Miami, Detection of sinkhole Sarah Fletcher, Massachusetts Institute of Technology, Maya Buchanan, Princeton University, Amplification of activity in centra Florida using high- spatial- resolution InSAR Uncertainty categorization, modeling, and management for flood frequencies with localsea- level rise and emerging time series observations water supply planning flood regimes Margaret Garcia, Tufts University, Modelling per capita Karoline Messenzehl, University of Bonn, Structural and Geomagnetism, Paleomagnetism, water demand change to support system planning thermal controls on the frequency and magnitude of small- and Electromagnetism Lidiia Iavorivska, Pennsylvania State University, Inputs of size rockfall events (European Swiss Alps) organic carbon to watersheds via atmospheric deposition: Katherine Serafin, Oregon State University, Location, Coordinator: Julie Bowles Variation across spatial and temporal scales location, location! Regional differences in morphologic and Stanislava Akimova, Institut de Physique du Globe de Cyndi Kelly, Stanford University, Back- projection imaging hydrodynamic controls on extreme total water levels along Paris, New archeointensity data from late Neolithic Yarim of extended pre-, co-, and post- eruptive seismic sources the West Coast of the United States Tepe 1 and 2 settlements (northern Iraq) dated from the pre- through multiple eruption cycles at Jefe geyser, El Tatio gey- Halaf and Halaf periods (7th–6th Millennia BC) ser field, Chile Near- Surface Geophysics Lydian Boschman, Utrecht University, On the enigmatic Xiuyuan Li, Lehigh University, Assessing the influence of Coordinators: Xavier Comas, Fred Day- Lewis, Sarah Kruse, birth of the Pacific plate within the Panthalassa Ocean climate variables on the past floods in continental USA George Tsoflias Pauline Le Maire, University of Strasbourg, 2D potential Theodore C. Lim, University of Pennsylvania, Beyond theory using complex algebra: New perspectives for interpre- imperviousness: A statistical approach to identifying func- Daniel Blatter, University of California, San Diego, Bayes- tation of aeromagnetic data tional differences between development morphologies on ian inversion of 2D models from airborne transient EM data Daniel Maxbauer, University of Minnesota, Magnetic min- variable source area-type response in urbanized watersheds Chao Gao, University of Maryland, Quantifying the erals in soils across the forest–prairie ecotone in NW Minne- Nathaniel Looker, University of Minnesota, Twin Cities, uncertainties and multi-parameter trade-offs in joint inver- sota Effects of land use/cover and landform on upper soil physical sion of receiver functions and surface wave velocity and properties in the highlands of Veracruz, Mexico ellipticity Global Environmental Change Kimberly Manago, Colorado School of Mines, Evaluating Samuel B. Kachuck, Cornell University, Sloppy inversion relationships between urban land cover composition and and optimal experiment design for Last Glacial Maximum Coordinators: Pierre Gentine, Lucy Hutyra, Dan Li, evapotranspiration in semi- arid regions Barents Sea ice sheet configuration Wenhong Li, Hui Su Stephen Maples, University of California, Davis, How to Farzaneh Mahmood Poor Dehkordy, University of Con- Stephen Decina, Boston University, Patterns and drivers recharge a confined alluvial aquifer system necticut, Studying exchange with less- mobile porosity at the of inorganic and organic nitrogen and phosphorus deposi- Christopher Marsh, University of Saskatchewan, The laboratory scale: Experimentation and multiphysics simulation, cycling, and loss throughout a metropolitan area Canadian Hydrological Model (CHM): A multi- scale, variable- tions Kira Hoffman, University of Victoria, Ecological legacies of complexity hydrological model for cold regions Adam Nielson, Colorado State University, Using synthetic indigenous fire management inhigh- latitude coastal temper- Natalie Nelson, University of Florida, Uncovering cyano- forward seismic models of channelized deepwater slope ate rainforests, Canada bacteria ecological networks from long- term monitoring data deposits to inform stratigraphic interpretation, Tres Pasos Richard Vachula, Brown University, A comprehensive using Granger causality analysis Formation, Magallanes Basin, Chile reconstruction of Alaskan Arctic fire history over the last Preston Pound, Georgia Southern University, Bacterial Kirk Scanlan, University of Alberta, Difficulties in interpret- 30,000 years as inferred from a novel multi-proxy suite of flux by net precipitation from the phyllosphere to the forest ing ballast degradation level estimates from synthetic organic geochemical and paleoecological methodology floor ground- penetrating radar data Daniel Wilusz, Johns Hopkins University, Can a simple Hydrology lumped parameter model simulate complex transit time dis- Nonlinear Geophysics tributions? Benchmarking experiments in a virtual watershed Coordinators: Terri Hogue, Rolf Hut, Alicia Kinoshita, Coordinators: Joern Davidsen, Steven Fletcher Margaret Zimmer, Duke University, Shallow and deep Kolja Rotzoll groundwater contributions to ephemeral streamflow genera- Sahani Pathiraja, University of New South Wales, Improv- Jane Barlow, University of Arizona, Assessing hydrologic tion ing forecasts through realistic uncertainty estimates: A novel impacts of future land cover change scenarios in the South data driven method for model uncertainty quantification in Platte River Basin (CO, WY, & NE) and the San Pedro River Mineral and Rock Physics data assimilation Basin (U.S./Mexico) Coordinator: Heather Watson Rachel Baum, University of North Carolina at Chapel Ocean Sciences Hill, Tradeoffs in risk and return of financial hedging solu- John A. Krantz, Brown University, Noble gas recycling: Coordinators: James Dykes, Donya Frank, Chris Hayes, tions to mitigate drought- related financial risks for water Experimental constraints on Ar, Kr, and Xe solubility in ser- Stephan Howden, Heidi Sosik utilities pentinite Danielle Boshers, University of Connecticut, Oxygen iso- Kathryn Kumamoto, Stanford University, Olivine strength Dylan Anderson, Oregon State University, Instantaneous tope composition of nitrate produced by freshwater nitrifica- in the low- temperature plasticity regime measured via spher- sediment bed level response to wave- induced pore- pressure tion ical nanoindentation gradients on a surfzone sandbar

Earth & Space Science News Eos.org // 37 AGU NEWS

Katie Bigham, University of Washington, Interpretation of Peiyun Zhu, University of Michigan, The influence of ice– Lukas Preiswerk, Swiss Federal Institute of Technology, the relationship between benthic fauna, geologic distribu- ocean interactions on Europa’s overturning circulation Zurich, Monitoring unstable glaciers with seismic noise inter- tions, and methane seeps at Southern Hydrate Ridge, Ore- ferometry gon Continental Margin Public Affairs Kathrin Spieker, University of Bergen, Fine- scale crustal Julius Busecke, Columbia University in the City of New structure of the Azores Islands from teleseismic receiver Coordinators: Denise Hills, Linda Rowan York, Time variable eddy mixing in the global sea surface functions salinity maxima Marshaun Montgomery, University of Illinois at Ruijia Wang, University of Alberta, An integrated investi- Yassir Eddebbar, University of California, San Diego, Urbana-Champaign, A framework for using rural markets gation of the induced seismicity near Crooked Lake, Alberta, Impacts of ENSO on air–sea oxygen exchange: Observations to analyze local food shortage resilience and mitigation Canada, in 2016 and mechanisms potential in sub-Saharan Africa based on evidence from Marcel Kleinherenbrink, Delft University of Technology, Zambia Space Physics and Aeronomy Separating steric sea level and ocean bottom pressure in the Amanda Sorensen, Rutgers, The State University of New Coordinators: Lindsay Glesener, Betsey Mitchell, tropical Asian seas Jersey, A case study of framing and project design impacts Allan Weathermax Lauren Kuntz, Harvard University, The Pacificventi- on participant identity, views, and trust of science in a phe- lated thermocline and its impact on global temperatures nology public participatory program Jeffrey Broll, University of Texas at San Antonio, Observa- Tianjia Liu, Columbia University in the City of New York, tions and simulations of specularly reflected He++ at Earth’s Global salinity predictors of western United States precipita- Seismology quasiperpendicular bow shock tion Sebastian De Pascuale, University of Iowa, Determining Coordinators: Miaki Ishii, Eric Kiser Julia Moriarty, Virginia Institute of Marine Science, The core plasmaspheric electron densities with the Van Allen effect of resuspension and deposition on biogeochemical Michael Afanasiev, Swiss Federal Institute of Technol- probes cycles in the northern Gulf of Mexico: Numerical modeling ogy, Zurich, Salvus: A flexible open-source package for Katherine Goodrich, University of Colorado, Boulder, results waveform modelling and inversion from laboratory to Classifying large- amplitude parallel electric fields along the Ajda Savarin, University of Miami, Diurnal cycle of convec- global scales magnetopause and their effect on magnetic reconnection tion and air–sea–land interaction associated with MJO over Yaochieh Chen, National Taiwan Normal University, Nils Peter Janitzek, University of Kiel, Differential stream- the Maritime Continent Research of repeating earthquakes and fault character in ing at 1 AU observed with SOHO/CELIAS/CTOF and ACE/ Meghan Shea, Stanford University, Use of a land- based, Chihshang Fault, Taiwan SWICS dual-parameter analyzer for tracking ocean acidification in Wenyuan Fan, University of California, San Diego, Zixu Liu, University of California, Los Angeles, Observa- nearshore coastal habitats Back-projection of large earthquakes: Advances and cave- tions of a new foreshock region upstream of a foreshock Elizabeth Weidner, University of New Hampshire, Quanti- ats bubble’s shock fication of methane gas flux and bubble fate on the eastern Dara Goldberg, University of California, San Diego, Earth- Andrew Marsh, University of California, Santa Cruz, Siberian Arctic shelf utilizing calibrated split- beam echo- quake early warning with seismogeodesy: Detection, loca- Hard X- ray detectability of small- scale coronal heating sounder data tion, and magnitude estimation events Kenneth Hudson, University of California, Santa Barbara, Tyler Mixa, University of Colorado, Boulder, Fine structure Paleoceanography and Paleoclimatology Site response during and after nonlinear soil behavior has influences on gravity wave propagation in the mesosphere occurred and lower thermosphere Coordinator: Matt Kirby Andrew J. Lloyd, Washington University, Full waveform Sam Schonfeld, New Mexico State University, Correcting Jeremy Caves, Stanford University, The Neogene de- adjoint seismic tomography of the Antarctic plate F10.7 for use in ionospheric models greening of Central Asia Kathryn Materna, University of California, Berkeley, Mea- Akshay Suresh, Indian Institute of Science Education and Danielle P. Santiago Ramos, Princeton University, Paired suring aseismic slip through characteristically repeating Research Pune, Wavelet based characterization of low radio measurements of K and Mg isotopes and clay authigenesis in earthquakes at the Mendocino Triple Junction, Northern Cali- frequency solar emissions marine sediments fornia Keith Wood, Auburn University, Field aligned currents Karen Vyverberg, University of Florida, New constraints Yajun Peng, Princeton University, Investigating complex derived from pressure profiles obtained from TWINS ENA from the Seychelles on the timing and magnitude of peak slow slip evolution with high- resolution tremor catalogs and images for geomagnetic storms that occurred on 01 June global mean sea level during the Last Interglacial numerical simulations 2013 and 17 March 2015 Maayan Yehudai, Columbia University in the City of New York, Changes in equatorial Atlantic Ocean thermohaline circulation across the mid- Pleistocene transition Planetary Sciences Get Eos highlights Coordinators: Nathan Bridges, Rosaly Lopes Michael E. Evans, Texas A&M University, Stepped acid in your inbox every Friday. extractions of CO2 from ancient carbonates in Martian nakh- lites (MIL 03346, 090030, 090032, 090036) show distinct δ18O and δ13C isotopic values compared to secondary terres- To sign up for the Eos Buzz newsletter, go to trial carbonates formed on ordinary chondrites (OC) collected from Antarctica publications.agu.org, scroll down, and enter your Daniel D. B. Koll, University of Chicago, Interpreting atmo- information in the “SIGN-UP FOR EOS BUZZ spheric circulations of rocky exoplanets as heat engines NEWSLETTER” section. Joseph O’Rourke, California Institute of Technology, Sus- taining a global magnetic field on Earth but not Venus with mantle dynamics

38 // Eos May 2017 AGU NEWS

Study of the Earth’s Deep Interior Daniel Evan Portner, University of Arizona, New finite- Chelsea Allison, Arizona State University, Improved frequency teleseismic P -wave tomography of the Anato- understanding of H2 O–CO2 solubility in alkali basalts at mid- Coordinator: Laurent Montesi lian sub- continent and the fate of the subducted Cyprean crustal pressures Eugenia Hyung, Harvard University, 142Nd/ 144Nd heteroge- slab Robert Bogue, Occidental College, Simultaneous in situ neity in the Proterozoic to Phanerozoic mantle and implica- Daniel Rasmussen, Columbia University in the City of CO2 soil flux and isotopic analysis in a high CO2 flux environ- tions for mantle mixing New York, Run-up to the 1999 sub-Plinian eruption of Shishal- ment at Mammoth Mountain, CA Kuangdai Leng, University of Oxford, AxiSEM3D: A new din volcano unveiled using petrologic and seismic Kara Brugman, Arizona State University, Clinopyroxene fast method for global wave propagation in 3- D Earth models approaches diffusion chronometry of the Scaup Lake rhyolite, Yellow- with undulating discontinuities Florian Schmid, Alfred Wegener Institute, Microseismicity stone Caldera, WY reveals extreme types of oceanic lithosphere, deep reaching Clare Donaldson, University of Cambridge, Relative seis- Tectonophysics fluid circulation and active diking at the Southwest Indian mic velocity variations correlate with deformation at Kīlauea Ridge volcano Coordinators: Kristin Morell, Julia Morgan Brandon Shuck, University of Texas at Austin, Evolution of Melissa Drignon, Oregon State University, Modeling the Susie Boote, University of South Carolina, Precambrian the upper lithosphere in the ENAM area from 3- D wide- angle re-equilibration processes between melt inclusions and their origin of the Brunswick magnetic anomaly: New insights seismic data host plagioclase megacrysts in plagioclase ultraphyric from the revised extent of the Suwannee Basin offshore Nicholas Stewart, University of Nice Sophia Antipolis, A basalts Jorge Alberto Castillo Castellanos, California Institute of new MATLAB code to automatically measure lateral and ver- Erin Fitch, University of Hawaii at Manoa, The mecha- Technology, Transition of the slab geometry at the eastern tical fault offsets in topographic data nisms and dynamics of high- energy lava– water explo- end of the Trans- Mexican Volcanic Belt from ambient noise Matthew Tarling, University of Otago, Slip dynamics and sions and earthquake surface waves the effects of metasomatism on fault rheology in ultramafic Elisabeth Gallant, University of South Florida, Terrestrial Helen A. Janiszewski, Columbia University in the City of rocks, the Livingstone Fault, New Zealand radar survey of Momotombo volcano, Nicaragua New York, Shoreline- crossing shear- velocity structure of the Josefine A. M. Nanne, Durham University, Osmium stable Juan de Fuca plate and Cascadia Subduction Zone from sur- Volcanology, Geochemistry, and Petrology isotope composition of chondrites and iron meteorites: Impli- face waves and receiver functions cations for planetary core formation Hannah Mark, Massachusetts Institute of Technology, Coordinators: Eric Brown, Sarah Brownlee, Brian Dreyer, Nick Joey Nelson, Stanford University, Effects of crystallinity on Seismic coupling at divergent plate boundaries from rate- Dygert, Brian Jicha, Sarah Lambart, Noah McLean, Sean Zn isotope fractionation during adsorption onto silica sur- and- state friction models Mulcahy, Wendy Nelson, Tyrone Rooney faces

Read the rst articles: Relating Coccidioidomycosis (Valley Fever) Incidence to Soil Moisture Conditions E. . Coopersmith, . E. Bell, . Benedict, . Shriber, O. McCotter, and M. . Cosh Mitochondria-mediated oxidative stress induced by desert dust in rat alveolar macrophages Michal ardo, Itzhak atra, ames . Schaeur, and Yinon Rudich Impact of hypoxia on gene expression patterns by the human pathogen, Vibrio vulni cus, and bacterial community composition Volume 1 • Issue 1 • June 2016 • Pages 1-57 in a North Carolina estuary Britney L. hippen and ames D. Oliver A Conceptual Model to Assess Stress-Associated Health E ects of Multiple Ecosystem Services Degraded by Disaster Events in the Gulf of Mexico and Elsewhere aul A. Sandifer, Landon C. napp, Tracy . Collier, Amanda L. ones, Robertaul uster, Christopher R. elble, Richard . wok, ohn V. Miglarese, Lawrence A. alinkas, Dwayne E. orter, Geoﬀ rey I. Scott, Lisa M. Smith, William C. Sullivan, and Ariana E. SuttonGrier

Submit your manuscript at geohealth.agu.org

Earth & Space Science News Eos.org // 39 RESEARCH SPOTLIGHT

Polar Interlopers in the Aurora Alexander Gerst/NASA Several times a day, the edges of Earth’s auroral rings brighten and arc toward the poles in events called poleward boundary intensifications, which a new paper suggests are caused by ionospheric polarization and flows of plasma from polar regions into the auroral oval.

arth’s aurora appears as a ring of high Fast polar cap flows, which transport iono- polarization. For another, PBIs last as long conductance around each pole, shifting spheric plasma from the dayside to nightside as the polar cap flow is touching the auroral E and undulating as the hours go by. The auroral oval across the polar cap, are strongly oval, a correlation that is difficult to explain poleward edge of this auroral oval also marks correlated to PBIs: The two occur together if they are caused by distant reconnection. a conductance boundary, often coinciding about 90% of the time. When these flows PBIs are also wider than polar cap flows: If with the boundary of the polar cap, where the make contact with the auroral oval, the PBIs were caused by distant reconnection, topology of Earth’s magnetic field lines polarization of the ionosphere at the edge of the reconnection would have to be inexplica- changes from closed loops at lower latitudes the auroral oval causes a field-aligned current bly triggered simultaneously inside and out- to open to the solar wind at higher latitudes. (FAC), a current of electrons that stream side the flow channel. Finally, PBIs are often Many times every day, the edge of the along Earth’s magnetic field lines. The followed by the movement toward the equa- aurora brightens in a poleward boundary authors hypothesize that FACs, if directed tor of the open-close boundary marking the intensification (PBI). PBIs have been studied upward, are accompanied by enhanced elec- edge of the polar cap, connecting PBIs to the extensively for decades, but researchers have tron precipitation, which would cause auroral enhanced polar cap convection. not yet conclusively determined their source. intensification, in other words, a PBI. These statistical characteristics, when Here Ohtani and Yoshikawa present an expla- This idea is supported by a number of considered together, suggest that the vast nation of how PBIs may be caused by iono- characteristics of PBIs. For one, PBIs start majority of PBIs are caused by ionospheric spheric convection, rather than the popular immediately when a polar cap flow touches polarization. ( Journal of Geophysical Research: idea that they could be caused by magnetic the auroral oval and have the same duration Space Physics, https://doi.org/10.1002/ reconnection far from Earth in the magneto- as the polar cap flow, which can be explained 2016JA023143, 2016) —Leah Crane, Freelance sphere. by the instantaneous nature of ionospheric Writer

40 // Eos May 2017 RESEARCH SPOTLIGHT

After Decades, High- Altitude Observations Revived at Jicamarca

hen the Jicamarca Radio Observa- to reproduce them was lost, as transmitters tory made its first observations of fell offline and Jicamarca focused on targets W Earth’s ionosphere in the early closer to the ground. 1960s, it was one of the most impressive Today, more than 50 years later, interest in facilities in the nascent field of space physics. high-altitude observations is on the rise, this Its massive square array of dipole antennas time driven by a desire to understand how was laid out in the Peruvian desert east of plasma behaves during geomagnetic storms. Lima, nearly 300 meters on each side. The Jicamarca remains one of the most important enormous radar facility was designed to probe space physics radar facilities, and fortunately, the ionosphere directly above Earth’s equa- recent upgrades have restored the facility’s tor; electrons in the ionosphere scatter the ability to carry out high-altitude observa- radar beams, but a faint return signal gives an tions. On 31 May 2016, Jicamarca fired up its indication of their density. transmitters and focused its antennas on In its initial observing runs, scientists high-altitude incoherent scatter in a study Alastair Philip Wiper/VIEW included measurements at very high alti- conducted by Hysell et al. Dipoles of the telescope at Jicamarca Radio Observa- tudes, an exercise meant to map out the In a 24-hour period of observations, the tory near Lima, Peru. Construction of the observatory space surrounding Earth. They also pushed team found that Jicamarca could profile the was completed in 1962, around the time this photo was the facility to its limits, requiring powerful electron density up to an altitude of roughly taken. radar pulses from all four of its transmitters 6300 kilometers. That’s high enough to use- and many people to operate them. Soon, fully overlap with data from ground-based only two transmitters, the data quality was however, high-altitude operations were can- magnetometers, which can cover a range similar to that of the 1965 data, with a celed; the last runs occurred in 1965. from roughly 3000 kilometers to 16,000 kilo- slightly better dynamic range. The team As the facility began to focus on more pop- meters. The data analysis also revealed that notes that future observations using all four ular areas of research, the unpublished high- different filtering methods did not change transmitters will be more sensitive and altitude records languished. Many were lost. the results much, which makes it easier to should push the observatory’s range occa- The details of the observations and analysis— interpret historical data. sionally up to 10,000 kilometers. ( Journal of such as which filtering methods, if any, were The authors used just two of Jicamarca’s Geophysical Research: Space Physics, https://doi used—faded away, limiting the surviving four transmitters, all of which have been .org/10.1002/2016JA023569, 2017) —Mark Zas- data’s usefulness. Eventually, the capability restored to operational status. Even with trow, Freelance Writer

River’s Rise Linked to Oklahoma’s Largest Earthquake

arthquakes do much more than literally In early September 2016, an earthquake heavy rains obscured the data. The pattern make the earth quake. The shifting of reaching 5.8 moment magnitude (an earth- of data collected is reminiscent of water E massive sheets of rock has an effect on quake rating scale used for the largest level fluctuations following past earth- all sorts of hydrogeological processes, affect- quakes) struck Pawnee, Okla., setting a state quakes. ing groundwater and surface water like rivers, record. If it was indeed a wastewater- The amount of extra water recorded is just lakes, and reservoirs. induced quake, it would be the largest such a fraction of the area’s annual water budget Some of this activity, however, is not natu- earthquake on record. The team of research- and will not affect residents’ water supply, ral. For example, geologists have extensively ers concluded that the quake was most likely the researchers say. But the Black Bear Creek documented that when wastewater is injected triggered by one or more of the 26 wastewa- case is important in that it proves that this deep into the Earth, as a means of disposal, it ter disposal wells within a 20-kilometer method of wastewater disposal has an can induce seismic activity, which could, in radius, given that it was a strike-slip event, impact on groundwater systems. Further- turn, have hydrogeological effects. As overall the type of earthquake most commonly more, if the number of induced earthquakes induced seismic activity has increased in fre- associated with induced quakes in Okla- continues to increase as it has, events like quency in recent years, scientists seek to learn homa, and had several other telltale physical this are likely to become more widespread. more about the secondary and potentially characteristics. To track this progress, the researchers hope residual impacts of human-induced quakes. Several hours into the Pawnee quake, the to continue to monitor and expand the exist- A recent study by Manga et al. is the first U.S. Geological Survey stream gauge nearest ing network of stream gauges. (Geophysical documented instance in which an earthquake the epicenter, located at Black Bear Creek, Research Letters, https://doi.org/10.1002/ that was most likely induced by wastewater began recording rising water levels. The 2016GL071268, 2016) —Sarah Witman, Freelance injection had a visible effect on surface water. increase continued for a full week, until Writer

Earth & Space Science News Eos.org // 41 RESEARCH SPOTLIGHT

What Proportion of River Nutrients Reaches the Open Sea?

lthough it is widely recognized that 6000 rivers to develop geograph- the world’s rivers deliver substantial ically based estimates of nutrient A amounts of dissolved nitrogen and delivery. phosphorus to coastal waters each year, the Their results suggest that 75% proportion of important nutrients that ulti- of nitrogen and 80% of phospho- mately reaches the open ocean is not pres- rus cross the continental shelves, ently known. Such estimates are crucial to delivering a total of 17 teragrams understanding how anthropogenic activity of nitrogen and 1.2 teragrams of and global climate change may affect global phosphorus from rivers to the biogeochemical cycles. open ocean each year. These sup- Most current nutrient cycling models unre- plies, however, vary depending alistically assume that all or none of the riv- upon several factors, including ers’ loads of dissolved nitrogen and phospho- the width of the continental rus reach the open sea. To improve upon this shelf, each river’s nutrient load, Madison and the MODIS science team all-or-nothing approach, Sharples et al. have and latitude. Latitude’s effect on

developed a new method for estimating the nutrient export varies between University of Space Science and Engineering Center, Liam Gumley, Wisconsin- proportion of nutrients that reaches the open 70% and 80% for nitrogen and Every year rivers deliver 55 million tons of nutrients to coastal seas. In a ocean following biogeochemical processing between 70% and 90% for phos- new study, researchers assess just how much of this river nutrient supply along the continental shelf. phorus. ends up in the open ocean. Using a mechanistic model that uses our Because these results ignore knowledge of how plumes of fresh river water nutrient processing within estu- behave after entering the sea, the team cre- aries, a parameter that is more difficult to understanding needs to be incorporated into ated a worldwide map of the average length estimate, these numbers should be consid- global geochemical models to realistically of time a given nutrient lingers within shelf ered upper limits, according to the team. project the response of coastal and oceanic ecosystems. The researchers then combined Despite this limitation, the study is an ecosystems to future warming. (Global Bio- these average durations with information important step forward in our understanding geochemical Cycles, https://doi.org/10. 1002/ about nutrient cycling in aquatic systems and of the spatial variability of nutrient process- 2016GB005483, 2017) —Terri Cook, Freelance a database of nutrient loads for more than ing on continental shelves. This improved Writer

Radar Method Shows Promise in Aquifer

he fine- scale structure of an aquifer is ground, limiting the clarity of perceived well as the output of traditional GPR analysis. difficult to determine, posing chal- underground features. In the newer approach Overall, full-waveform inversion analysis T lenges for scientists trying to predict used by the team, a technique called full- showed a strong correspondence with the underground water flow and transport. In a waveform inversion more accurately recon- hydrogeological data. new paper, Gueting et al. demonstrate the structs the wave’s path, allowing for In one hydrogeological experiment, a tracer potential for recent advances in ground- improved resolution. injected into a borehole flowed downstream, penetrating radar (GPR) to image aquifer The researchers used full- waveform inver- where its concentration was detected at vari- structure in unprecedented detail. sion of cross- borehole GPR data to investi- ous points. Full-waveform inversion analysis The researchers used a new approach to a gate underground water dynamics at an allu- suggested the presence of a thin layer of sand method known as cross- borehole GPR. In vial aquifer near Cologne, Germany. Using that would explain the observed tracer con- this technique, a transmitter placed in a several densely spaced boreholes, they took centrations. This sand layer was not detected borehole emits an electromagnetic wave that measurements along cross sections that were using traditional GPR data analysis, demon- travels to a receiver in another borehole sev- 50 meters long and 10 meters deep. Repeated strating the strength of full- waveform inver- eral meters away. Underground features dis- measurements with the transmitter and sion. rupt the wave as it travels, so the altered receiver placed in slightly different positions Currently, this study is one of just a few wave picked up by the receiver contains allowed them to construct images of the that have investigated GPR full-waveform information about the structure of these aquifer structure with a resolution at the inversion. The scientists hope that their features. Analysis of the wave data can then scale of decimeters. results will encourage a growing number of reveal these structures. To determine the true benefit of the full- researchers to use the new technique. (Water Traditional GPR data analysis uses a math- waveform inversion technique, the scientists Resources Research, https://doi.org/10. 1002/ ematical method that strongly simplifies the then compared its output with data gathered 2016WR019498, 2017) —Sarah Stanley, Freelance presumed path of the wave through the using standard hydrogeological methods, as Writer

42 // Eos May 2017 RESEARCH SPOTLIGHT

When Income Goes Up, Does Pollution Go Down? iStock.com/Alexmia

oes economic development always damage water quality, or 1985 to 2006. Over the same period, they used economic growth with does increased income actually help decrease pollution? per capita income, available from the U.S. Bureau of Economic Analy- D Researchers have been studying the question for a long time, sis. and its answer may help communities or countries better predict their Because the researchers were looking at multiple pollutants, they environmental future. decided to use a seemingly unrelated partially linear model (SUPLM) One hypothesis is that for a time, a region’s environmental degra- for the study. This model is often used in economics to combine dation will increase as wealth increases, but at a certain income level multiple equations that are related only through their errors. the environment will start to recover. For water quality and air qual- The results indicated that nitrogen did follow a Kuznets curve, as ity, scientists have found data supporting this idea in research at the did dissolved oxygen, meaning that water quality in Louisiana country level, in both developed and developing countries. The bell- improved with increased wealth. Phosphorus and mercury both told shaped environmental Kuznets curve (EKC) graphs a hypothetical a different story: Although phosphorus pollution did decrease when relationship between pollution and the average income earned per state per capita income rose to $14,000, the pollution increased person in a given area. again after a per capita income of $17,000. A similar problem hap- In a recent study, Pandit and Paudel used models to look at the rela- pened with mercury, indicating that mercury pollution rose the sec- tionship between water pollutants in watersheds and income in the ond time perhaps because of the increased demand for power and state of Louisiana to see whether an EKC exists that shows eventual energy. water quality recovery due to increased incomes in the state. The mixed results show that the factors that fix pollution are com- The scientists focused on nitrogen, phosphorus, dissolved oxygen, plicated, but some pollutants, like nitrogen, could be reduced by eco- and mercury to test water quality. So-called flow pollutants like nitro- nomic growth. What this study does not answer, as the authors point gen and phosphorus (typically associated with agricultural pollution) out, is whether this pollution automatically fell with income growth or can be absorbed back into the environment. These types of pollutants whether it was the result of environmentally protective policies in the contrast with “stock pollutants” such as mercury, which, once put state. The authors suggest that a combination of these factors likely into the environment, will not disappear or be absorbed. Instead, they had some relation to improvement in water quality. will continue to cause damage and cycle through the environment for- This research did not find that economic growth will naturally solve ever. Mercury is usually locked away in rocks and coal but is released pollution and water quality issues, but this growing area of research into the environment when coal is burned to produce electricity or will be of interest to both environmentalists and economists investi- when burning hazardous waste. gating the connection between industrial development and water pol- The authors used watershed data (including data on water pollu- lution. (Water Resources Research, https://doi.org/10. 1002/ tion) covering 53 counties in Louisiana over a 21-year period, from 2016WR018655, 2016) —Alexandra Branscombe, Freelance Writer

Earth & Space Science News Eos.org // 43 POSITIONS AVAILABLE

Jiann Lin ([email protected]) Atmospheric Sciences AGU’s Career Center is the main resource for and/or Lucas Harris (lucas.harris@ noaa.gov). recruitment advertising. Postdoctoral Research Associate, Princeton University is an equal Princeton University opportunity/affirmative action The Atmospheric and Oceanic Sci- employer and all qualified applicants All Positions Available and additional job postings can ences Program at Princeton Univer- will receive consideration for employ- be viewed at https://eos.org/jobs-support. sity, in association with NOAA’s Geo- ment without regard to age, race, color, physical Fluid Dynamics Laboratory religion, sex, sexual orientation, gen- (GFDL), seeks a postdoctoral or a more AGU offers printed recruitment advertising in Eos to der identity or expression, national senior scientist to conduct frontier origin, disability status, protected vet- reinforce your online job visibility and your brand. studies on the predictability and gene- eran status, or any other characteristic sis mechanisms of severe convective protected by law. Visit employers.agu.org to view all of the packages storms over the continental Unites available for recruitment advertising. States using available satellite and radar observations to validate a Geochemistry newly-developed global cloud- resolving model (supported by the Part- Time Lecturer, Tufts SIMPLE TO RECRUIT Next Generation Global Prediction University– Mineralogy and Petrol- System project) with two-way global- ogy • online packages to access our Career Center audience to-regional nested grid capability, Tufts University invites applica- • 30-day and 60-day options available with the ultimate goal of transitioning tions for a one-year appointment as the prediction capability into opera- part-time lecturer in the Department • prices range $475–$1,215 tional forecasting. of Earth and Ocean Sciences (EOS) to The selected candidate will have a teach a 2-semester sequence in Min- CHALLENGING TO RECRUIT Ph.D. in meteorology, atmospheric eralogy (Fall 2017) and Igneous and sciences, or a related field. The candi- Metamorphic Petrology (Spring 2018). • online and print packages to access the wider AGU community dates should have substantial back- The successful candidate will be • 30-day and 60-day options available grounds in observations, theory, and/ expected to teach these courses along or modeling in tropical meteorology with their labs to mostly undergradu- prices range $795–$2,691 • (e.g., tropical cyclones), convective- ate Geology and Geological Sciences scale storms (e.g., supercell thunder- majors. The EOS Department is well- DIFFICULT TO RECRUIT storms and derechoes), and associated equipped for undergraduate study in analysis skill, to develop tools to aid mineralogy and petrology with a • our most powerful packages for maximum multimedia exposure model developers in building a next teaching lab that has petrographic to the AGU community generation multi-scale prediction sys- microscopes, a comprehensive collec- tem for high-impact weather events. tion of minerals and igneous and met- • 30-day and 60-day options available The positions are for one year amorphic rocks, rock saws, thin sec- • prices range $2,245–$5,841 renewable for up to three years pend- tion preparation equipment, and a ing satisfactory progress and contin- scanning electron microscope with FREE TO RECRUIT ued funding. The positions are subject EDS capability. Tufts University is to Princeton University’s background located in the Boston area and is near check policy. a diverse array of different igneous packages apply only to student and graduate student • Applicants must apply online and and metamorphic rock terrains con- roles and all bookings are subject to AGU approval submit a CV, publication list, contact ducive to field trips in New England. information for at least 3 references, Preferred qualifications include a • eligible roles include: student fellowships, internships, and a one-to-two page statement of Ph.D. in mineralogy or petrology and assistantships, and scholarships research interests should be submit- teaching experience in these disci- ted to https://www.princeton.edu/ plines. All application materials must acad-positions/position/1261. For be submitted via Interfolio at https:// additional information contact Shian- apply.interfolio.com/40440. Please • Eos is monthly. Deadlines for ads in each issue are published at http://sites.agu.org/media-kits/eos- published advertising-deadlines/.

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44 // Eos May 2017 POSITIONS AVAILABLE

submit the following: 1) a letter of through departmental support. CHWR relevant research experience and world- leading research university, to application including a statement of will provide strong supports to the suc- interests, and the contact information lead the higher education reform in teaching philosophy and experience in cessful candidates to apply for national for two referees. Send all documenta- China, to serve the needs of innovation- both teaching and research or practice and provincial research grants. tion in 1 PDF file please. oriented national development and the in mineralogy and petrology, 2) a cur- All candidates must hold a Ph.D. in needs of building Shenzhen into a mod- riculum vitae, and 3) the names (with hydrology, water resources, ecology, Interdisciplinary ern, international and innovative met- contact addresses) of three references. and other related fields. The candidates ropolitan. These positions are created Questions about the position can be should demonstrate a strong publica- Assistant/Associate/Full Professors- with a significant development to estab- directed to Professor Jack Ridge, Chair, tion potential in hydrology, water Physical and biological Oceanogra- lish a vigorous research program in Department of Earth and Ocean Sci- resources, and other related fields (at phy, marine geophysics/geology, The oceanography at SUSTech to serve the ences, at [email protected]. Review least 2 first-author papers published in Southern University of Science and national call for China’s important role of applications will begin on March 10, internationally recognized journals). Technology in deep sea research and resource- 2017 and will continue until the posi- Total income is up to 210,000 RMB/ The department of oceanography at oriented exploration in the world tion is filled. year (appx. 30,000USD/Year) and com- the Southern University of Science and oceans. Tufts University, founded in 1852, mensurate with research outputs. Technology of China (SUSTech) invites To apply send a cover letter, com- prioritizes quality teaching, highly Review of applications will begin upon applications for tenure-track (or ten- plete vitae with list of publications, competitive basic and applied research receipt until the position is filled. ured) faculty positions at the ranks of and three names of references to and a commitment to active citizen- Materials should be sent to: tao.yang@ Assistant, Associate, and Full Profes- [email protected], or to Dr. Y. John ship locally, regionally and globally. hhu.edu.cn. sors. Applicants must have earned Chen, Chair Professor at Department Tufts University also prides itself on doctoral degrees in marine geophysics/ of Oceanography, Southern University creating a diverse, equitable, and inclu- Post- Doctoral Opportunity – Uncer- geology, physical oceanography, bio- of Science and Technology, No 1088, sive community. Current and prospec- tainty in Climate Change Modeling, logical oceanography and ocean engi- Xueyuan Rd., Xili, Nanshan District, tive employees of the university are University of Manitoba neering or closely related fields. Suc- Shenzhen, Guangdong, China 518055. expected to have and continuously We are seeking a highly motivated cessful applicants will be expected to develop skill in, and disposition for, post-doctoral researcher with strong establish a robust, externally funded Cluster Hiring in Geo- positively engaging with a diverse pop- academic experience in hydrologic research program and demonstrate Bioinformatics/Environmental ulation of faculty, staff, and students. modeling and statistical analyses to strong commitment to undergraduate Genomics and Organic Biogeochem- Tufts University is an Equal Opportu- examine the impacts of regulation and and graduate teaching, student men- istry, The Southern University of nity/ Affirmative Action Employer. We climate change on freshwater inputs to toring, and professional services. Science and Technology are committed to increasing the diver- Hudson Bay. The successful candidate These positions will remain open until The Southern University of Science sity of our faculty and staff and foster- for this position will be working with filled. and Technology (known as SUSTech or ing their success when hired. Members the freshwater systems team of the SUSTech is a young university at SUSTC) (http://www.sustc.edu.cn/en) of underrepresented groups are wel- BaySys project (an NSERC-funded col- Shenzhen, China (next to Hong Kong) was founded in 2011 with public fund- come and strongly encouraged to apply. laborative research project) to quantify since 2010 which is set to become a ing from Shenzhen, a dynamic city If you are an applicant with a disability the relative contributions to changes who is unable to use our online tools to in magnitude and timing from climate search and apply for jobs, please contact change, model uncertainty, and regu- us by calling Johny Laine in the Office of lation of the Nelson and La Grande Equal Opportunity (OEO) at 617.627. Rivers. Candidates will work in close 3298 or at [email protected]. collaboration with industry (Manitoba Applicants can learn more about Hydro, Hydro Quebec) and will be requesting reasonable accommodations expected to contribute to presenta- at http://oeo.tufts.edu. tions for the industrial partners, and author peer-reviewed publications. Hydrology Applicants should have a strong background in the areas of hydrologic Multiple Post- doctoral Positions in modeling and statistical analyses spe- Water Sciences, Hohai University cifically related to uncertainty assess- Established in 1915, Hohai Univer- ment, and preferably have experience sity (HHU) is the leader of innovation with climate change simulation. Special and development of higher education consideration will be given to those in hydraulic engineering and water sci- candidates who have had exposure to ences in China. HHU is located at Nan- programming in R, Matlab, and For- jing, Jiangsu, China. Nanjing is the tran. internationally recognized capital of The successful candidate will study Jiangsu province, one of the largest cit- jointly within the Faculty of Engineer- ies in China. ing (Department of Civil Engineering) The College of Hydrology and Water and Centre for Earth Observation Sci- Resources (CHWR) at HHU invites ence (CEOS) at the University of Mani- applications for multiple postdoctoral toba, Winnipeg MB, Canada. Housed positions in water sciences, to start as within the Clayton H. Riddell Faculty of early as March 2017. The positions are Environment Earth and Resources, open until filled, including (1) 3 posi- CEOS is home to 15 full time faculty, tions in watershed hydrological simu- and approximately 70 other students lation, (2) 3 positions in water and staff devoted to the study of Arctic resources management, water marine science. The Centre is located in resources planning, water resources the newly developed Nellie Cournoyea utilization and protection, or water Arctic Research Facility. Graduate stu- resource policy, and (3) 3 positions in dents have access to state-of-the-art atmospheric- hydrological coupled field and laboratory facilities. CEOS is a modeling system, land surface model, founding member of the new interna- or ecohydrology. tional Arctic Science Partnership. The successful candidates will con- Applications should be emailed duct independent, externally funded Dr. Trish Stadnyk (Tricia.Stadnyk@ research programs in their field of umanitoba.ca) expertise. Support for developing an Please include in your application a active research agenda is provided CV, transcripts, a short statement of

Earth & Space Science News Eos.org // 45 POSITIONS AVAILABLE

that has been viewed as the vanguard Program (http://www.sustc.edu.cn/en/ of China’s development in science and faculty_en). technology. The goal of SUSTech is to Applicants are required to have a become a top-tier international uni- Ph.D. degree in earth sciences, biology, versity that excels in interdisciplinary chemistry, computer science, or related research, talent development and disciplines. Post- doctoral experiences knowledge discovery. are preferred but not required. Candi- Siting at the mouth of the Pearl dates must have a proven and consistent River flowing to the South China Sea, track record of high-quality scientific the newly born (2015) Department of publications and good communication Ocean Science and Engineering at SUS- skills. Chinese and English are required Tech aims to become a major player in languages for teaching. To apply, please education and research in ocean sci- submit the following material electroni- ences in China. It will be housed in a cally to [email protected]: 1) Cover brand new building on the beautiful letter; 2) Curriculum vitae (with a com- SUSTech campus, with ample labora- plete list of publications); 3) Statement tory space that is equipped with the lat- of research and teaching interests; 4) est technology for conducting cutting Reprints of three recent papers; and 5) edge research. The 5000 ton R/V Shen- Names and contact information for zhen is in the planning stage of con- three references. All positions remain struction, which is expected to be built open until filled. by 2022. The Institute for Geo-Omics Faculty Positions available in the Research (TIGOR) at SUSTech aims to School of Environmental Science become an open platform for world and Engineering, The Southern Uni- class research in microbial oceanogra- versity of Science and Technology phy and geomicrobiology, and an invit- The Southern University of Science ing home for domestic and overseas and Technology (known as SUSTech or scientists to exchange ideas and SUSTC) (http://www.sustc.edu.cn/en) together advance the field of ocean sci- was founded in 2011 with public fund- ences. In the early stage of TIGOR’s ing from Shenzhen City. A thriving growth, the priority will be to build two metropolis of 20 million people bor- research strengths: Geo- Bioinformatics/ dering Hong Kong, Shenzhen has often Environmental Genomics and Organic been referred to as the “Silicon Valley Biogeochemistry. The integration of of China” with strong telecommunica- these strengths will allow us to study tion, biotechnology and pharmaceuti- systematically the evolution of life on cal sectors. The goal of SUSTech is to early Earth, microbial ecology impacted become a top-tier international uni- by human activity, mechanisms of bio- versity that excels in interdisciplinary organic interactions in the deep ocean, research, talent development and and fundamentals of biogeochemistry knowledge discovery. English is the (e.g. lipid biosynthesis and bio- language of instruction. fractionation of isotopes of life- The School of Environmental Sci- essential elements). ence and Engineering at SUSTech was In Geo- Bioinformatics/Environ - established in May 2015 to provide a mental Genomics hiring, we seek new platform for performing cutting- highly qualified candidates (at the edge research and for training a new assistant or associate professor levels) generation of environmental scien- who are able to apply bioinformatics tists, engineers and managers who are techniques (metagenomics, multi- interdisciplinary, innovative and omic integrative analysis, in silico global- thinking. Currently the school lead discovery from microbial metab- has 18 full time faculty members olites and computational biology (http://ese.sustc.edu.cn/en/) with 30 or algorithm/server development) to more tenure- track/tenured positions analyze data from the next- to be filled. In addition to a generous generation sequencing and other startup package to each tenured or high- throughput sequence profiling tenure track faculty position, the to address fundamental questions school was recently awarded a 3-year mentioned above. Candidates with grant of 50 million RMB (~7 million strong ecological backgrounds are USD) to strengthen its 5 core areas of particularly encouraged to apply. research. Moreover, the school is in In Organic Biogeochemistry hiring, line to receive 120 million RMB (~18 we seek highly qualified candidates (at million USD) for research instrument the assistant, associate or full profes- capability development. sor levels) with strong skills in mass Applications are invited for faculty spectrometry and isotope geochemis- positions at all ranks. Areas of interest try. The candidates are expected to include, but are not limited to, water apply GC-MS, LC-MS (Orbitrap or ion pollution and treatment, environmen- mobility Q-TOF), FT-ICR MS, or AMS tal (soil, groundwater, ecosystem) to address questions mentioned above. remediation and restoration, hydrology Highly competitive salaries and and water resources engineering, bio- benefit packages will be provided to geochemistry, environmental microbi- the hired candidates, who may also be ology, atmospheric chemistry, air pol- eligible for additional government lution control, air quality engineering, support such as the Shenzhen City’s solid waste treatment and utilization, Peacock Program and the Chinese environmental health risk assessment, Government’s One Thousand Talents environmental health interventions,

46 // Eos May 2017 POSITIONS AVAILABLE

remote sensing of the environment, Hydrographic Science Faculty Posi- global change, and environmental tion, University of Southern Missis- management. Highly competitive sala- sippi ries and benefit packages will be pro- The University of Southern Missis- vided to tenure- track/tenured faculty. sippi’s School of Ocean Science and New hires may be eligible for additional Technology (SOST), Division of Marine government support such as the Shen- Science (DMS; http://www.usm.edu/ zhen City’s Peacock Program and the marine/) at the NASA John C. Stennis Chinese Government’s One Thousand Space Center (SSC) is offering a posi- Talents Program (http://www.sustc tion in hydrographic science at the .edu.cn/en/faculty_en). tenure-track, Assistant or Associate Applicants are required to have a Professor level. Applicants should Ph.D. degree in environmental sci- hold a Ph.D. in a hydrographic science and engineering, earth and ence, marine science, geomatics engi- METER Group, Inc. USA is seeking a Product atmospheric sciences, or related dis- neering, ocean engineering, or closely Development Scienti st (Product Owner) ciplines. Post-doctoral experiences related field. Applicants will have at the M.S. or Ph.D. level with some are preferred but not required. Candi- demonstrated field and research dates must have a proven and consis- experience in acoustic and LIDAR- micrometeorology or atmospheric science fi eld tent track record of high-quality sci- based hydrographic and bathymetric instrumentati on experience and opti mally also entific publications and good surveying, and precise positioning at communication skills. Chinese lan- sea. Proficiency in commercial soft- plant science experti se. This individual will guage skill is a plus but not required. ware packages used to collect and work with a dedicated team of engineers and To apply, submit the following mate- process hydrographic data is scienti sts to develop new instrumentati on for rials electronically to [email protected]. expected. Also desirable is an interest cn: 1) Cover Letter; 2) Curriculum in applying hydrographic technolo- Environmental/Ag/Atmospheric/Plant Science Vitae (with a complete list of publica- gies to collaborative opportunities in researchers. tions); 3) Statement of research and marine science, including biological, teaching interest; 4) Selected reprints chemical, physical, geological and of three recent papers; and 5) Names fisheries oceanography. A nationally Responsibiliti es: and contact information for five ref- recognized record of publication, erences. All positions remain open demonstrated successful grantsman- until filled. For additional informa- ship, and at least 5 years service at a • Provide product ownership of METER’s ATMOS tion, contact Xiaoli Wang, Email: degree-granting institution or equiv- and PHYTOS product lines, which include [email protected], phone: +86- alent service at a non-degree granting 755-8801-0821. institution are needed at the atmospheric and plant measurements Associate-level. A successful candi- • Lead dedicated product development team, Graduate Student Research and date is expected to conduct an active acti ng as the subject matt er expert Teaching Assistantships- Env, Earth research program and participate in & Atmos Sciences, University of the hydrographic science master’s • Regularly interact with customers at Massachusetts, Lowell program, which is recognized at the tradeshows, customer sites, etc., to develop The Department of Environmental, Category-A (Cat-A) level by the Inter- Earth, and Atmospheric Sciences national Hydrographic Organization. product vision and allow development team to (EEAS) at the University of Massachu- The latter efforts include curricula iterate and make bett er products setts Lowell (www.uml.edu/sciences/ review, delivery and development of eeas) offers several graduate research the program, and faculty experience and teaching assistantships for moti- in delivering a Cat-A hydrographic Minimum Qualifi cati ons include: vated students for the Fall 2017 science curricula are highly desirable. semester. Several positions are cur- The development of courses for a new rently open, including in: Geochronol- hydrography emphasis in the under- • M.S. or Ph.D. with research/coursework in ogy and Isotope Geochemistry (Prof. graduate Marine Science degree pro- Environmental Biophysics, Atmospheric Science, Richard Gaschnig), Extreme Precipita- gram is also expected. Climatology, Micrometeorology, or related fi eld tion in the Northeast US (Prof. Mat- Along with DMS, SOST integrates thew Barlow), Arctic Greenhouse Gas the Gulf Coast Research Laboratory, • Field instrumentati on experience during Cycling (Prof. Daniel Obrist), Clima- the Division of Coastal Sciences, and research program tology of Snow Squalls in the Eastern the University’s fleet of five research U.S. (Prof. Frank Colby), Buried Ice in vessels, to form a regionally, nation- • Plant science coursework or research Antarctica (Prof. Kate Swanger), and ally and internationally recognized • Excellent verbal and writt en communicati on Environmental Mercury Cycling (Prof. leader in marine science. DMS is skills Daniel Obrist). Further information home to an interdisciplinary program about these positions can be found on of graduate and undergraduate study • General knowledge of current research and our webpage. and research in marine environments. monitoring needs in these areas and willingness The University of Massachusetts Seventeen on-site faculty conduct Lowell (also known as UMass Lowell) research and teach courses in biologi- to routi nely communicate with researchers to is an urban public research university cal oceanography, marine chemistry, learn more in Lowell, Massachusetts, with nearly geological oceanography, physical • Ability to travel as much as 3 weeks/quarter 1,150 faculty members and 18,058 stu- oceanography, remote sensing, dents. EEAS offers unique interdisci- numerical modeling, and hydrography • Ability to manage complex projects from start plinary study programs encompassing to ~50 full-time graduate students at to fi nish, oft en with competi ng prioriti es Geosciences, Meteorology, Hydrology, SSC and ~40 undergraduates at the and Environmental Chemistry. EEAS USM Gulf Park campus. The Division • Background check results sati sfactory to offers undergraduate and graduate offers Marine Science B.S., M.S. and METER degrees in Environmental Sciences, Ph.D. degrees and a Hydrographic Sci- with concentrations in Environmental ence M.S. Located at SSC, Marine Sci- • At least three professional or academic Studies, Geosciences, and Atmo- ence is strategically situated at the references will be required during the interview spheric Sciences. Graduate School single largest concentration of ocean- process admission policies are found under ographers and hydrographers in the https://www.uml.edu/grad/. world. Faculty interact with research

Earth & Space Science News Eos.org // 47 POSITIONS AVAILABLE

scientists at government agencies senior candidate for research related hydroclimate, climate dynamics, techniques as applied to marine located on site and at the Joint Air- to how cryosphere-aerosol interac- snow hydrology, cryosphere science, microfossils from sediment cores and borne Lidar Bathymet y Center of tions affect hydroclimate variability or a closely related field; (b) experi- with demonstrated accomplishments Excellence (JALBTCX) including the over High Mountain Asia. A key focus ence using and analyzing advanced in related research areas. Please apply Naval Oceanographic Office, Naval will require comparing observations climate models and observational at http://www.whoi.edu/jobs. Meteorology and Oceanography Com- and high-resolution global climate datasets (including remote sensing mand (CNMOC), Naval Research Lab- model output to understand hydrocli- data); (c) strong diagnostic skills in Planetary Sciences oratory (NRL-SSC), USACE, NOAA, mate variability over High Mountain analyzing large data sets. USGS, and NASA. Asia with a particular emphasis on Candidate must have a PhD. Initial Research Scientist–Mars Science, Applicants should submit a letter the cryosphere-aerosol interactions appointment is for one year with the Jet Propulsion Laboratory (JPL) of interest outlining their qualifica- and related processes. This will possibility of renewal subject to sat- The Planetary Science section at tions for the position, including a include an assessment of presently isfactory performance and available the Jet Propulsion Laboratory (JPL) in research plan, teaching philosophy available and future developmental funding. Pasadena, CA is looking to fill a posi- with a curricular plan, a curriculum satellite-based data products and Complete applications, including a tion for a researcher in areas relevant vitae, and names and contact infor- other regional observational or CV, publication list, at least 3 letters to future planetary sample return mation of at least four references. model-based reanalyses. This will of recommendation, and a short missions. Applications must be submitted also include an assessment of statement of research interests The position is to conduct Mars- online at https://jobs.usm.edu. For aerosol-climate interactions in the should be submitted by May 5, 2017 related scientific research within one inquiries about the position, contact region and targeted analysis to better for full consideration. of the following fields: Geology, Geo- Stephan Howden, Chair of the Search understand how aerosol deposition Applicants must apply online to chemistry, Geomorphology, Astrobi- Committee, at 1-228-688-5284 or and its variability may affect regional https://www.princeton.edu/acad ology, and Petrology. The candidate [email protected]. Review of hydroclimate in both the historical -positions/position/1221. For addi- should have a PhD in planetary sci- applications begins 1 February 2017 record and the future. The research tional information, you may contact ence, or related scientific discipline, and continues until the position is will also examine how the cryosphere Dr. Sarah Kapnick (sarah.kapnick@ along with demonstrated experience filled, with an anticipated start date of and hydroclimate respond to natural noaa.gov) or Dr. Paul Ginoux (paul in conceiving, defining, and conduct- August 2017. variability and radiative forcing .[email protected]). ing independent scientific research, AA/EOE/ADAI changes over the next 100 years. This This position is subject to the Uni- with a strong interest in applying position will provide the opportunity versity’s background check policy. those efforts to problems related to Postdoctoral Research Associate in for collaboration within GFDL and Princeton University is an equal the origin, evolution and/or habit- Understanding Cryosphere-Aerosol Princeton University, as well as with opportunity/affirmative action ability of Mars including the study of Interactions Over High Mountain members of the NASA High Mountain employer and all qualified applicants results from orbital and in situ Mar- Asia, Princeton University Asia Team at various institutions. will receive consideration for tian measurements and/or extrater- The Atmospheric and Oceanic Sci- Travel to meet with collaborators will employment without regard to age, restrial samples. ences Program at Princeton Univer- be encouraged, but not required. race, color, religion, sex, sexual ori- It is expected that the successful sity, in association with NOAA’s Geo- The selected candidate will have entation, gender identity or expres- candidate will pursue new mission physical Fluid Dynamics Laboratory one or more of the following attri- sion, national origin, disability sta- and/or instrument opportunities (GFDL), seeks a postdoctoral or more butes: (a) a strong background in tus, protected veteran status, or any focusing on Martian exploration other characteristic protected by law. through advocacy and outreach within the scientific and stakeholder Ocean Sciences community. This pursuit will involve working closely with science and Postdoctoral Investigator, Woods engineering teams at JPL to design Hole Oceanographic Institution solar system sample return and Mar- As part of a project funded by the tian exploration missions and instru- National Science Foundation, a posi- mentation. tion for a Postdoctoral Investigator is The candidate is also expected to available in the Department of Geol- participate in long-lead activities ogy and Geophysics at Woods Hole related to humans-to-Mars being Oceanographic Institution. We invite coordinated by the Mars Program PLACE applications for the position to Office. This may involve participating investigate abrupt changes in ocean in engineering-led planning teams, circulation during the last glacial interaction with personnel involved cycle. The initial appointment is for in similar efforts at other NASA loca- one year with the possibility of an tions, helping to play a coordination extension based on funding and per- role with the interested external formance. Review of applications community, participation in relevant will begin immediately and continue committees, involvement in subject until the position is filled. The start conferences, and maintaining exter- YOUR AD date is flexible, but preference will nal visibility through publication. be given to qualified candidates who The position may include a signifi- are available to begin by August 1, cant start up funding package. 2017. To view the full job description and The institution has a top-rated apply to the position, please visit: postdoctoral program that supports a www.jpl.nasa.gov/opportunities/, dynamic postdoctoral community (see Requisition # 2017-7983). Candi- with formal mentoring and career dates should submit a CV that guidance programs. While the pri- includes a list of publications and an HERE mary focus of the work will be in introductory cover letter (no more research, the postdoctoral investiga- than 2 pages) that includes research, tor will have an opportunity to partic- research goals and the names and ipate in educational and outreach contact information of references. activities associated with the project. JPL is a Federally-Funded Research (www.whoi.edu/postdoctoral/) and Development Center operated by Visit Careers.agu.org to learn more about employment advertising with AGU Desired education and experience: the California Institute of Technology Recent Ph.D. in Earth or Ocean Sci- for NASA. JPL/Caltech is an equal ences or related disciplines, experi- opportunity/affirmative action ence with trace element analytical employer.

48 // Eos May 2017 Postcards from the Field

Hi, Folks.

Artist Mike Carroll and I went to Mount Ere- bus in Antarctica, under the auspices of the National Science Foundation’s Writers and Artists Program, to do a book comparing landscapes on Erebus with those on icy moons. Here I am (in red) descending into Hut Cave on the slopes of Erebus, aided by mountaineer Evan Miller (in blue). These ice caves are truly otherworldly features, and we can imagine that they might exist on Europa or Enceladus.

—Rosaly Lopes, Jet Propulsion Laboratory, Pasadena, Calif.

View more postcards at http://americangeophysicalunion.tumblr .com/ tagged/postcards-from-the-ﬁ eld. Editors in Chief Needed

AGU is looking for two dynamic, well-organized scientists with high editorial standards and strong leadership skills to serve a 4-year term as editor in chief (EIC) for Reviews of Geophysics or Global Biogeochemical Cycles. The EIC is the principal architect of the scientific content of the journal. The EIC is an active scientist, well-known and well-regarded in his/her discipline, and must be active in soliciting the best science from the best scientists to be published in the journal. Working with the other editors and AGU staff, the EIC is the arbiter of the content of the journal. Among other functions, the EIC is responsible for: • Act as an ambassador to the author/editor/reviewer/ scientist community. • Set the strategy for the journal. • Lead the editor selection process. • Assign and balance review work load. • Decisions of ethics. • Review and contribute to periodic monitoring reports. • Conduct and attend meetings. If you would like to be considered, send your CV with a letter of interest via email to [email protected]. If you would like to nominate a highly qualified colleague, send a letter of recommendation to the same email address. Please make sure to include the name of the journal in the subject line.

Application Deadline: 15 May 2017