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A Closer Look at the Sustainability of Our Groundwater Aquifers

Fri, 10/19/2018 - 11:39

The largest aquifers in the world are a vital source of freshwater for agriculture and other human uses. During times of drought, these resources are crucial to food security; understanding groundwater storage and depletion is vital, especially as climate change worsens drought conditions.

Remote sensing allows researchers to get an accurate look at water storage dynamics on a global scale. NASA’s Gravity Recovery and Climate Experiment (GRACE) satellites measure monthly gravitational anomalies that can be used to track changes in aquifer groundwater storage. However, these data alone are not enough to determine the sustainability of aquifers over time or gauge how sustainability may be affected by anthropogenic influences.

To tackle this problem, Thomas et al. paired GRACE data with specific sustainability indicators to analyze the world’s largest aquifers. They incorporated groundwater storage data from their GRACE Groundwater Drought Index (GGDI) tool and focused on three primary performance indicators: reliability, resilience, and vulnerability. These indicators, typically used in water resources systems, characterize the likelihood of the aquifer’s ability to be used dependably in the future.

Aquifers in arid regions like the Sahara, the Arabian Peninsula, and California’s Central Valley exhibited high vulnerability and low resilience. These aquifers are overstressed and nonrenewable; however, their large storage capacity can make up for slow recharge time, so they also ranked as more reliable. In contrast, aquifers in northern latitudes and regions with high precipitation had low reliability scores but high resilience scores due to faster recharge. Because vulnerability is largely influenced by groundwater recharge, the least vulnerable aquifers were found in lush regions like equatorial Africa and northern Europe and Asia.

Next, the researchers calculated a sustainability index to track changes across all three performance indicators. The least sustainable aquifers were located in the Sahara, the Arabian Peninsula, and northern India; the team found that sustainability was determined by patterns in groundwater use, as well as by aquifer response to withdrawals and natural variability. Ultimately, combining GGDI data with the new sustainability indicators provides a new method of quantifying and monitoring aquifer sustainability through time and continued use.

This study demonstrates the importance of an integrated approach to assessing aquifer sustainability and the factors that influence it. A new metric of unique sustainability indicators for aquifers can be used to improve water resources management in a warming world. (Geophysical Research Letters, https://doi.org/10.1002/2017GL076005, 2017)

—Lily Strelich, Freelance Writer

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U.S. Mint Unveils Design for Special Apollo 11 Coin

Fri, 10/19/2018 - 11:38

That’s some small pocket change for mankind.

The U.S. Mint, which manufactures the nation’s legal coinage, has unveiled its commemorative designs for coins that celebrate the 50th anniversary of NASA’s inspirational July 1969 Apollo 11 mission that succeeded in landing the first people on the Moon.

The four commemorative coins that could soon be clinking in your pocket include a $5 gold, $1 silver, half dollar clad, and 5-ounce silver proof coin. All are etched with images and words that evoke Apollo 11 and the culmination of that mission as “one small step for man, one giant leap for mankind.”

The coins, which will go on sale in January 2019, feature on the obverse side an image of a footprint on the lunar surface and inscriptions that recognize NASA’s Mercury, Gemini, and Apollo programs that led up to the first Moon landing. The reverse side shows the visor and part of the helmet of astronaut Buzz Aldrin; the helmet’s reflection portrays astronaut Neil Armstrong, the lunar lander, and the American flag.

Evoking and Honoring the Apollo Legacy

The coins are “a wonderful way to remember the concerted national effort behind the amazing accomplishment, but also a stepping off point to think about what’s next.”The coin design’s unveiling “kicks off the national celebration of the Apollo anniversaries,” said Ellen Stofan, director of the Smithsonian’s National Air and Space Museum, which hosted an 11 October event to announce the design in Washington, D. C. That date was the 50th anniversary of the launch of Apollo 7, which was the first successful crewed Apollo space mission.

The coins, she said, are “a wonderful way to remember the concerted national effort behind the amazing accomplishment, but also a stepping off point to think about what’s next.”

“We honor the legacy of Apollo with a great celebration of the 50-year anniversary of Apollo, but I think we also honor Apollo by going further,” said NASA deputy chief of staff Gabriel Sherman, speaking at the event. “Where we want to go is to Mars, and there is no better proving ground for an eventual journey to Mars than right there on the Moon.”

“Let us hope that the desire to explore will remain a permanent fixture in the history of America and the world.”On hand, too, was Apollo 7 pilot Walter Cunningham, who said that “space is now part of the American character, maybe one of the best parts. Pushing boundaries and embracing exploration is a part of our human spirit. Let us hope that the desire to explore will remain a permanent fixture in the history of America and the world.”

Cunningham recalled his mission and President John Kennedy’s pledge to land an American on the Moon by the end of the 1960s. “We didn’t know everything to expect,” Cunningham said, “but we knew that we didn’t have much time left if we were going to beat the Russians to the Moon by the end of that decade.”

Hoping That the Coins Sell Out

Proceeds from the sale of these coins will support the Air and Space Museum’s Destination Moon exhibit, the Astronauts Memorial Foundation, and the Astronaut Scholarship Foundation. David Ryder, director of the U.S. Mint, said that if the commemorative coin program sells out, it could raise millions of dollars for those programs. “I’m all over that [goal]. I’m going to do whatever I have to do to make sure that happens,” he said.

A snapshot from the 11 October 2018 unveiling ceremony for the design of the Apollo 11 50th Anniversary Commemorative Coin Program. The ceremony was held at the National Air and Space Museum, in Washington, D. C. Walter Cunningham, Apollo 7 astronaut, and Sheryl Chaffee, daughter of Apollo astronaut Roger Chaffee and a representative of the Astronauts Memorial Foundation, unveil the reverse side of the coin. Also pictured, from left to right, are Curtis Brown, representing the Astronaut Scholarship Foundation; Ellen R. Stofan, director of the National Air and Space Museum; and David Ryder, director of the U.S. Mint. Credit: Jim Preston/Smithsonian’s National Air and Space Museum

Congress authorized the commemorative coin program in bipartisan legislation that the House and Senate approved by voice vote before it was signed into law in December 2016. Rep. Bill Posey (R-Fla.), a member of the House Committee on Science, Space, and Technology, was a cosponsor of the legislation.

Posey told Eos that he hopes that the coins might be somewhat of a respite from the current bitter political atmosphere. “One of the least divisive issues in Congress generally has been the space program,” said Posey, who remembers that he was at a friend’s house when the Apollo 11 astronauts walked on the Moon.

“I watched the landing on TV. I was holding my four-month-old daughter up to the TV screen, so she could see,” Posey said. “She didn’t know what she was seeing, but I wanted [her] to say that she saw the first man step on the Moon.”

—Randy Showstack (@RandyShowstack), Staff Writer

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Air Pollution Reduces Arctic Cloud Lifetime, Study Suggests

Fri, 10/19/2018 - 11:38

Fossil fuel emissions from Asia and Europe may be cutting down the life expectancy of Arctic clouds, reducing the clouds’ ability to regulate temperatures in the polar region, according to new research.

A new study published in Geophysical Research Letters, a journal of the American Geophysical Union, suggests pollution plumes coming predominately from Northeast Asia and Northern Europe travel to the Arctic region and allow cloud droplets to freeze at higher temperatures.

This phenomenon triggers earlier than normal snowfall and can reduce the clouds’ lifetime, according to the new research.  The shorter the clouds live, the less they are able to regulate temperatures at the surface, the study’s authors said.

Pollution has been known to disrupt Arctic temperatures by introducing greenhouse gases into the atmosphere, but the new finding suggests another process by which pollution from mid-latitudes can disrupt polar temperatures. This previously unquantified effect represents a valuable piece of the Arctic climate change puzzle, according to the study’s authors.

“The Arctic has a climate that is changing very rapidly, and the warming is more intense than the warming that we have in the middle latitudes,” said Quentin Coopman, an atmospheric scientist at the Institute of Meteorology and Climate Research at Karlsruhe Institute of Technology in Karlsruhe, Germany and lead author of the new study, which was completed while Coopman was a graduate student at the University of Utah and the University of Lille.

Along with increasing temperatures, the Arctic is experiencing record lows of sea ice extent in recent years according to the National Oceanic and Atmospheric Administration.

“We focused on the pollution and cloud interaction, but it is part of a bigger system including the sea ice and the atmosphere of the Arctic and (greenhouse) gas and aerosols for example,” Coopman added. “Our results will help modeling studies better predict the evolution of the climate in the Arctic.”

Not many sources of pollution exist in the Arctic but pollutants from combusted fossil fuels coming from other areas of the world can invade the region through atmospheric circulation patterns, Coopman said. Once the pollution arrives, it becomes trapped for weeks or months under a temperature inversion, where a layer of warm air rests above cooler air near the surface and prevents the pollution from escaping into the upper atmosphere or depositing on the surface.

Clouds can either cool or warm surface temperatures in the Arctic, depending on where they form and how much sea ice is present. Clouds above sea ice trap some of the sunlight reflected and heat emitted by the ice, which can warm the surface. But clouds above ocean water, which is much less reflective than ice, block sunlight and have a cooling effect. Collectively, these processes are key in regulating Arctic surface temperatures.

Pollution plume from Siberia mixing with clouds in the Arctic in July 2012. Contour lines indicate carbon monoxide concentrations. Ice clouds appear blue and liquid clouds appear white and gray. Credit: NASA and Quentin Coopman

Previous research conducted by Coopman and his colleagues showed Arctic cloud properties are extremely sensitive to pollution. They found clouds in the Arctic were two to eight times more sensitive to air pollution than clouds at other latitudes.

In the new study, the researchers wanted to further investigate how air pollution affects Arctic clouds. They combined data from satellite images of Arctic clouds with atmospheric models used to simulate carbon monoxide, a by-product of incomplete combustion used as a tracer for pollution coming from mid-latitudes.

The new study’s results suggest pollution plumes lower the amount of cooling needed for cloud droplets to freeze by about 4 degrees Celsius (7.2 degrees Fahrenheit), a much stronger impact than expected, Coopman said. This means cloud droplets can freeze at higher temperatures. When cloud droplets freeze more readily, snowfall occurs sooner, which can decrease the clouds’ lifetimes and inhibits their ability to regulate temperatures at the surface, according to the study’s authors.

The new study did not examine how much this change in cloud formation is affecting surface temperatures but the study’s authors said previous work suggests a reduction of cloud lifetime would have an overall cooling effect on the surface and a warming effect in the upper atmosphere.

“Small changes can have very strong consequences in the Arctic region because the atmosphere is very dry, the temperature is very cold, and the clouds are at the edge of existence, so any addition of pollution will have a strong impact on the clouds,” Coopman said.

Marc Salzmann, a research scientist at the Institute for Meteorology at the University of Leipzig in Germany who was not involved with the new study, noted that although the study suggests combustion aerosols to be the cause of the change in freezing temperature, more research needs to be done to show what exactly about the plumes leads to this shift.

“Carbon monoxide is used as a marker for air pollution in this study, but it is obviously not the carbon monoxide itself that causes this,” Salzmann said. “It would therefore certainly be very interesting to find out which physical processes may cause this correlation.”

The post Air Pollution Reduces Arctic Cloud Lifetime, Study Suggests appeared first on Eos.

Can Coastal Surface Currents Improve Hurricane Forecasts?

Thu, 10/18/2018 - 12:05

The study by Li and Toumi [2018] is the first to explore the possibility of using observed surface currents in order to improve forecasts of hurricane intensity. They use an idealized model set up, which shows promising results. This is an important new methodological development which could potentially improve hurricane intensity forecasts. However, the method would first need to be tested more broadly and in more realistic simulations before it can be considered to be integrated in current forecast systems by the tropical cyclones forecasting agencies, such as the National Hurricane Center.

Citation: Li, Y., & Toumi, R. [2018]. Improved tropical cyclone intensity forecasts by assimilating coastal surface currents in an idealized study. Geophysical Research Letters, 45. https://doi.org/10.1029/2018GL079677

—Suzana Camargo, Editor, Geophysical Research Letters

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Mercury Mission Will Map Morphology and Measure Magnetics

Thu, 10/18/2018 - 12:04

The first planet will soon receive its third visitor from Earth.

The visitor, a spacecraft called BepiColombo, is set to launch as early as this weekend. BepiColombo will contain two orbiters, a propulsion unit, and a strong Sun shield to protect it from solar radiation.

BepiColombo aims to study the geophysics, atmosphere, and magnetosphere of Mercury.BepiColombo aims to study the geophysics, atmosphere, and magnetosphere of Mercury as well as to understand the history of the inner solar system. The spacecraft is a joint mission of the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) and will be ESA’s first mission to travel inward toward the Sun.

Two Missions for One Launch

The mission is primarily composed of two orbital craft, one each developed by ESA and JAXA. ESA’s Mercury Planetary Orbiter (MPO) contains an altimeter as well as multiwavelength imagers and spectrometers to study Mercury’s morphology, geochemistry, and composition. JAXA’s Mercury Magnetospheric Orbiter (MMO) hosts a magnetometer, a spectral imager, and plasma physics instruments to study the origin, strength, and extent of the planet’s magnetic field and exosphere.

“The long journey to Mercury has not yet started, but I feel the two science orbiters already have a strong bond between them, thanks to the long history of this mission,” Go Murakami, BepiColombo project scientist at JAXA, said in a statement. “I believe they will achieve a very successful mission with their joint science measurements.”

BepiColombo will create a high-resolution global map of Mercury’s surface at many wavelengths.To be successful, however, BepiColombo must weather some extreme conditions. Temperatures at Mercury range from extremely hot, up to 450°C, to extremely cold, down to –180°C. MPO’s instruments will use temperature-resistant layers and a coating over its outside as well as radiators and heat pipes to carry away heat created inside the craft. MMO will use a Sun shield before arrival and, afterward, a combination of reflective panels and spinning to reduce and redistribute the heat.

Together, the instruments on BepiColombo will also create a high-resolution global map of Mercury’s surface at many wavelengths. This map, combined with its other investigations, seeks to complement the data collected by previous visits to Mercury. Mercury is the least explored of the four rocky inner planets, having received visits only from NASA missions Mariner 10, from 1974 to 1975, and Mercury Surface, Space Environment, Geochemistry and Ranging (MESSENGER), from 2008 to 2015.

Mysterious Mercury Artist’s rendering of BepiColombo near Mercury. Credit: ESA/ATG MediaLab, NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Mercury is an odd terrestrial planet in many ways. It is the only solar system planet that has a spin-orbit resonance: It spins on its axis three times for every two orbits around the Sun. One year on Mercury is only 88 Earth days long, but a day-night cycle on the smallest planet lasts more than twice as long. It also has the highest orbital eccentricity of any planet and virtually no axial tilt.

That means that some places on Mercury don’t see sunlight for 2 Mercury years, some are in perpetual “high noon” for weeks at a time, and others occasionally see the Sun reverse direction just after rising or just before setting. Some deep impact craters near the poles never see sunlight at all, and scientists have detected water ice deposits trapped within their shadowed basins.

Mercury also is the most heavily cratered of the terrestrial planets, has a solid iron core that dominates its interior structure, and has an evolving orbit that can be explained only using Einstein’s theory of general relativity. It also shows signs of past tectonics and volcanism and has a thin atmosphere. Many of these features were unexpected discoveries from Mariner 10 or MESSENGER.

BepiColombo’s mission scientists hope that studying each of these properties in more detail will provide a deeper understanding of the history of the inner solar system and how planets close to their stars evolve.

Fighting the Sun’s Pull

Traveling in a controlled manner toward the Sun requires more energy than traveling away. The craft must constantly fight the Sun’s gravitational pull to achieve orbital insertion around Mercury. In addition to its solar-electric propulsion system, BepiColombo will control its inward spiral to the Sun by borrowing gravitational energy during a flyby of Earth, two of Venus, and six of Mercury.

BepiColombo’s journey from launch to orbit will take 7 years. Once at Mercury, its mission lifetime will be about 17 months.

BepiColombo is scheduled to launch no earlier than Friday, 19 October, at 9:45 p.m. Eastern time aboard an Ariane 5 rocket. To learn more about BepiColombo’s design and mission goals, watch the video below.

—Kimberly M. S. Cartier (@AstroKimCartier), Staff Writer

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Making Sense of Landslide Danger After Kerala’s Floods

Thu, 10/18/2018 - 12:03

Every summer, monsoon rains come to southwestern India. This summer, however, the deluge brought the worst flooding in a century.

Slurries of water, soil, rock, and vegetation overwhelmed villages, downed power lines, and cut some communities off from receiving immediate aid.The resulting destruction killed nearly 500 people, inundated cities, and collapsed bridges. The rains also caused thousands of landslides in mountainous regions after torrents of water loosened soils from hillslopes. These slurries of water, soil, rock, and vegetation overwhelmed villages, downed power lines, and cut some communities off from receiving immediate aid.

Following the disaster, a team of geoscientists traveled to the devastated state of Kerala to survey landslide damage. Their ground survey, which was finished last month, uncovered new insights into what triggered the dangerous slides in the region.

“We observed that most of the landslides occurred in areas where recent construction had happened,” Thomas Oommen, associate professor at Michigan Technological University, told Eos. The team’s findings also discovered evidence of large subsurface channels flowing under the soil, a new factor they hope to incorporate in future hazard models.

But landslide hazards in the region aren’t over now that the summer monsoon has ceased. The region’s northeast monsoon is slated to begin later this month. More rain means that more slides could occur soon, the researchers warn.

The Monsoon of a Century

Summer monsoon rains began to fall in Kerala last May. In the months following, storm after storm brought 2.4 meters of rain to the state in just 87 days. The amount was well above the region’s usual monsoon levels and nearly triple the amount Elizabethtown, N.C., received from Hurricane Florence last month.

Oommen watched the floods unfold from afar and knew that scientists needed to survey the effects of the rain quickly, while landslide scars were still fresh.The intense rainfall took its toll: More than 493 people died, and the state suffered $2.7 billion in damages. The effort to rebuild continues, with many people still living in relief camps.

Oommen, who is from Kerala, watched the floods unfold from afar and knew that scientists needed to survey the effects of the rain quickly, while landslide scars were still fresh. So in late August after rains had ceased, he reached out to a fund sponsored by the National Science Foundation (NSF) that awards grants to those with the contacts to undertake rapid reconnaissance after disasters.

NSF agreed to send him and a team of landslide geoscientists—Sajinkumar K.S., Richard Coffman, and Vishnu C.L.—to the mountains of Kerala. One week later, Oommen packed his bags and boarded a plane to India.

A First Glimpse at the Floods

On 3 September, the team of researchers met in the Kerala city of Thiruvananthapuram. Their first stop was 3 hours north, in the state’s Alappuzha District, a region that sits along the coast between the inland Vembanad Lake and the waters of the Arabian Sea.

When they got there, the scientists were taken aback by what they found. “To our surprise, there were over 3,500 houses still flooded in the Kainakary area,” Oommen said. They did not expect to see houses still flooded nearly 2 weeks after the rain abated, he said.

(left) A car makes cautious progress through the flooded streets of the Alappuzha District of Kerala, India, on 4 September 2018. (right) A flooded home in Kerala’s Alappuzha District on 5 September 2018. Credit: Thomas Oommen

The region sits below average sea level, and an embankment between agricultural fields and the city had been washed away in the flood. As the city worked to rebuild the wall and pump out water, the damage became apparent: At houses where the water had receded, the scientists saw foundations starting to sink into the ground.

Alappuzha “is known as the ‘Rice Bowl of Kerala’ for its paddy fields,” Oommen explained. The fields were almost ready for harvest before the monsoon came, he noted. But instead they were destroyed by the rains.

The floods, they knew, were just one symptom of the downpours. Another hazard lay upslope in the mountains from which the floodwaters came: landslides. As landslide geologists, the crux of their fieldwork lay there.

Highlands

The researchers drove east, toward the lush Idukki District of Kerala. Idukki lies within the Western Ghats, a mountain range draped with tropical forests that stretches along the west coast of India.

They encountered what they had suspected: The heavy rain from the monsoon had saturated hillsides of the Ghats during the summer months, triggering more than 1,000 landslides according to initial reports that Oommen received from the government. Those estimates indicated that in Idukki alone, the slides buried 161 structures and damaged roughly another 2,000.

Debris from a landslide butts against homes in Idukki, stacking dirt and vegetation onto roofs on 20 August 2018. Credit: I&PRD, Government of Kerala

Traveling around Idukki, often on roads reduced to one lane because of debris, the scientists encountered landslides abutting roadsides and sluicing through villages. They saw gigantic slides that had left whole hillsides bare. The landslides also “severely damaged or totally destroyed” the roads in Idukki, said Oommen, leaving towns stranded for weeks at a time.

Mapping Land on the Move

The team of scientists set out to map some of the recent slides before the forest swallowed the evidence. “Being a tropical climate, all the manifestations of landslides will be erased very soon due to intense growth of bushy vegetation,” said Sajinkumar, a member of the reconnaissance team and an assistant professor of geology at the University of Kerala.

At many of the slides they encountered, the researchers stopped to take photographs, using a thermal camera to measure underlying moisture and drainage channels below the soil. They probed the soil on and around recent slides using a cone penetrometer to check the strength of the soil. And in some cases they traced the perimeter of the slide by foot, plotting the edges with GPS.

After the researchers studied roughly 40 slides, of which they took detailed measurements of nearly a dozen, the scientists began to notice two distinct causes for the landslides: one natural and one human caused.

The researchers found this large hole in a landslide photographed on 7 September 2018 and believe it is evidence of a subsurface piping phenomenon that can destabilize hillslopes. Credit: Thomas Oommen

The natural cause of the landslides was the simple reality of steep terrain being bombarded with too much water. When the torrential rain bore down on the slopes of the Western Ghats, the water percolated under the surface of the soil and tried to flow downhill. In certain areas, subsurface “pipes” formed, carving water channels under the soil. These pipes either quickly drained subsurface water, destabilizing hillslopes, or became clogged, creating a backlog of water that grew larger and larger until the entire slope gave way. In some places, the underground pipes “reached a maximum of 20 centimeters” in diameter, Sajinkumar said.

Human activity triggered most of the slides.But these types of natural slides were in the minority, Oommen noted. The researchers found that human activity triggered most of the slides.

When people build new structures, Oommen explained, “the terrain is typically altered by the cutting of slopes and removal of soil.” Slicing into the slope transforms the runoff pattern and opens up new ways for water to seep underground. “The increased infiltration,” Oommen said, “destabilizes the slope and leads to landslides.”

Building on Shifting Ground

A study released 2 months ago in Natural Hazards and Earth System Sciences documented a steady rise in fatal landslides that had been triggered by human activities, particularly in Asia. Oommen and Sajinkumar saw this playing out in near-real time, with construction practices aggravating the existing landslide hazards.

A massive landslide at Government College in Munnar, India, photographed on 20 September 2018. Credit: I&PRD, Government of Kerala

For example, a massive landslide near Government College in Munnar in Idukki sent soil cascading down the hillside earlier this month, wiping out several newly built buildings, Sajinkumar noted. Fortunately, no one was injured in the landslide.

The college’s authorities extended the campus within the landslide scarp, forgoing the warning from previous studies.This slide came on the heels of other tragic losses in the community: More than a dozen monsoon-related deaths occurred during the month of August, including a family swept away by a landslide in the night.

Sajinkumar said that officials at the college should hardly be surprised by the most recent slide on campus. In that same location, a landslide had previously occurred in 2005, destroying a building in its path. After the 2005 slide, Sajinkumar published a study diagnosing the type of slide (a “head-ward retreating landslide”), and he warned that the slope would likely fail again in strong rainfall.

“However, the college authorities extended the campus within the landslide scarp, forgoing the warning from previous studies,” he said.

More Risks to Come?

Unlike the college, some communities may not have had studies that warn of possible disasters.

“We saw fear on their faces….They are traumatized and live in constant fear of rain.”The scientists visited the village of Panniyarkutty, where five people were killed when a landslide swept over several houses. When the team of scientists visited, residents were still searching for the bodies of three victims.

“While speaking with the neighbors of the deceased, we saw fear on their faces,” Oommen said. “They are traumatized and live in constant fear of rain.”

The researchers said that the cause of the deadly slide in Panniyarkutty was not immediately clear. They didn’t find evidence of recent construction or natural piping. Oommen suspects that the area may serve as a valley that several slopes drain into, but he said that further hydrologic analysis is needed.

The researchers worry that the devastation might not be over for Panniyarkutty and other communities in high-risk zones. “The district is expecting another spell of rain in October” from the northeast monsoon, explained Sajinkumar. Slopes on the verge of collapse, called aborted landslides, could become destabilized and grow into full landslides when another rainstorm strikes.

“These aborted landslides can get reactivated in this spell of rain,” said Sajinkumar. Given the danger, he explained, “it is advisable not to have human habitations in these highly vulnerable areas.”

A view, taken on 7 September 2018, of a landslide in Panniyarkutty that destroyed several houses and killed five people. Two houses lie here beneath this rubble, along with the bodies of three people whose remains had not yet been found. Credit: Thomas Oommen

However, families in Panniyarkutty face substantial difficulties trying to rebuild or relocate. “Many low-income families lost their homes, in which they had invested all their savings,” said Oommen. “Due to the high population density,” Sajinkumar added, “people are forced to occupy the hilly areas without accounting for the landslide susceptibility.”

Turning Disaster into Knowledge

Oommen and Sajinkumar released an atlas of landslide hazards in Kerala last year, and they plan to update their book with the results of their ground survey last month. Specifically, they intend to add the piping phenomenon into their hydrologic estimates.

Despite their warnings, the researchers worry that local governments won’t act decisively to mitigate future hazards.“I think incorporating these subsurface channels could improve our estimates,” Oommen said.

But despite their warnings, the researchers worry that local governments won’t act decisively to mitigate future hazards. Previous reports had indicated many vulnerable areas should be excluded from future development, Oommen noted. “But there has been a lot of pressure from the political parties not to implement that,” he said.

Sajinkumar agreed. The “absence of strong legislation” coupled with “the lack of will to enforce existing regulations” made the risks posed by these hazards worse, he said.

A house knocked off its foundation lies in shambles after a landslide struck it from behind in Mavadi in the Idukki District on 6 September 2018. Credit: Sajinkumar K.S.

The government really needs to step up to resolve these issues,” Oommen added. Otherwise, he noted, “people just carry on the same way. That’s what we have seen in the past.”

But, “hopefully, this time it will be different,” he said.

—Jenessa Duncombe (@jenessaduncombe), News Writing and Production Intern

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Seeing Mars in a Grain of Sand

Wed, 10/17/2018 - 11:13

Dunes are arguably one of the simplest geologic systems there is—piles of sand blown around by wind—and they abound in the solar system. As such, they offer a unique opportunity to test our understanding of how simple sedimentary processes are affected by different environmental conditions.

Until recently, however, the study of extraterrestrial dunes was restricted to orbiter-based imagery and few martian ripple fields observed close-up by the Mars Exploration Rovers, Spirit and Opportunity. Between November 2015 and April 2017, the Mars Science Laboratory (MSL) Curiosity rover traversed, for the first time in humankind, an active dune field on another planet—the Bagnold Dunes of Gale crater.

Curiosity’s scientific campaign at the dunes was organized in two phases. Phase 1 occurred near the northern, trailing edge of the dune field during the low-wind season (southern fall/winter), while Phase 2 occurred near the southern edge of the dune field during the high-wind season (southern summer).

Curiosity’s traverse (white line) and two-phase investigation of the Bagnold Dunes. Inset shows the study location (white rectangle) within Gale crater. Credit: after Lapotre and Rampe, 2018

During Phase 1 (November 2015-February 2016), Curiosity investigated two crescent-shaped dunes (or barchans), Namib Dune and High Dune. A broad range of scientific questions related to wind processes was addressed using the rover’s suite of instruments (Bridges and Ehlmann, 2018) through an extensive campaign spanning wind measurements, detailed observations of sand grains, ripples, and dunes, and a characterization of physical properties as well as the chemical and mineral composition of windblown materials.

Results from Phase 1 were presented in a special issue of JGR: Planets (see also corresponding Editors’ Vox by Ehlmann and Rogers). However, because Phase 1 took place during the low-wind season, several questions related to the dynamics of the dunes remained unanswered. Furthermore, sampling windblown sands in a single location did not permit the characterization of possible spatial variations in composition.

Mosaic of Mast Camera (Mastcam) images showing the downwind face (stoss) of Namib Dune, acquired on sol 1196 during Phase 1 of the science campaign. Credit: NASA/JPL-Caltech/MSSS

The MSL Science Team thus decided to extend the scientific investigation of the dunes to include a second phase further along the rover traverse during the windy season (Lapotre and Rampe, 2018). Phase 2 (February–April 2017) took place near a linear dune, the Nathan Bridges Dune, and a ripple field, Mount Desert Island. In contrast to the barchan dunes investigated during Phase 1, the Nathan Bridges Dune, named by the team in honor of our dearly missed friend and eolian expert Nathan Bridges, is longitudinal to oblique, i.e., its crest is roughly parallel to the average wind direction. Curiosity also inspected a few isolated ripples and ripple fields on its way to higher stratigraphic levels on the crater’s central mound. The results of the second phase investigations are presented within a new special collection of Geophysical Research Letters.

The findings presented in the special collection encompass a broad array of questions that remained unanswered after Phase 1 and integrate across observations made throughout the entire campaign. Some of the key results are described below.

Weitz et al. [2018] present a characterization of grain sizes and shapes within and outside of the active dune field. Although sand is dust free and narrowly distributed within the active portion of the dune field (with a median grain size ~100-150 µm), isolated ripples and ripples in ripple fields south of the Bagnold Dunes have coarser crests (typically ~300-500 µm and up to >1 mm) and some are covered by a thin veneer of dust.

The paper by Lapotre et al. [2018] described the observation of a rich diversity in bedform morphology and dynamics. Specifically, large (meter-scale wavelength) ripples that are alien to Earth’s sandy deserts but are ubiquitous on Mars are found to not only form transversely (like those seen during Phase 1) but also longitudinally or obliquely to the average wind direction.

Mastcam mosaic of transverse coarse-grained ripples. Enchanted Island, sol 1752. Credit: NASA/JPL-Caltech/MSSS

Baker et al. [2018] made estimates of sand fluxes during the windy season based on direct observations of the migration of small, decimeter-scale impact ripples by up to a few centimeters per martian day (or sol).

Curiosity’s shadow over potential sampling targets for compositional analysis at Ogunquit Beach, Mount Desert Island. Navcam mosaic, sol 1648. Credit: NASA/JPL-Caltech/MSSS

O’Connell-Cooper et al. [2018] present in situ measurements of the geochemical composition of windblown materials, including sand and dust. The coarser fractions show enrichments in Fe, Mg, Ni, and Mn, consistent with an enrichment of mafic minerals in coarser grains, an enrichment in felsic components in finer sand, and a depletion of S, Cl, and Zn across all sand sizes.

Gabriel et al. [2018] show that active sands are also shown to contain very low H relative to other soil targets within Gale crater. In contrast, the paper by Lasue et al. [2018] shows that fine dust is found to be enriched in S and Cl.

In addition, Stern et al. [2018] characterized the volatile content of windblown sands, and found that the Bagnold Dunes contain more oxychlorine, carbon, and nitrate than other soils of Gale crater, but less adsorbed water than dusty soils.

The papers by Johnson et al. [2018] and Rampe et al. [2018] present remote and in situ measurements of mineral composition of actively transported sand. Combined with observations made during Phase 1, these measurements indicate an overall basaltic composition with subtle spatial variations in composition with position on individual bedforms and across the dune field. These variations likely reflect wind-driven sorting of sand by grain size and composition, and the possible incorporation of materials derived from local bedrock.

Finally, Miller et al., [2018] explore in situ constraints on the influence that sand dunes have on local, high-frequency temperature fluctuations.

Altogether, observations made by Curiosity at the Bagnold Dunes further our understanding of modern martian eolian processes at scales that are unachievable by current orbiting cameras and spectrometers. They also help to refine the sedimentological and geochemical models used to interpret ancient rocks on other planets.

—Mathieu G. A. Lapotre (email: mlapotre@fas.harvard.edu), Harvard University, Cambridge, Mass.

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Energetic Electrons Can Penetrate the Stratosphere

Wed, 10/17/2018 - 11:10

Precipitations of energetic electrons from the radiation belts influence the Earth’s atmosphere. Using polar satellites and a ground-based radar in Antarctica, Kavanagh et al. [2018] show that electrons with energies of more than 30 kiloelectron volts penetrate the slot region even under modest geomagnetic activity. The precipitation lasts 10 days on average and penetrates to the stratopause (55 kilometers altitude). Such energetic electrons likely contribute to the destruction of ozone at such low altitudes and cause changes in the atmospheric chemistry to be taken into account in models.

Citation: Kavanagh, A. J., Cobbett, N., & Kirsch, P. [2018]. Radiation Belt slot region filling events: Sustained energetic precipitation into the mesosphere. Journal of Geophysical Research: Space Physics, 123. https://doi.org/10.1029/2018JA025890

—Viviane Pierrard, Editor, JGR: Space Physics

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Antarctic Ice Shelf “Sings” as Winds Whip Across Its Surface

Wed, 10/17/2018 - 11:09

Winds blowing across snow dunes on Antarctica’s Ross Ice Shelf cause the massive ice slab’s surface to vibrate, producing a near-constant set of seismic “tones” scientists could potentially use to monitor changes in the ice shelf from afar, according to new research.

The Ross Ice Shelf is Antarctica’s largest ice shelf, a Texas-sized plate of glacial ice fed from the icy continent’s interior that floats atop the Southern Ocean. The ice shelf buttresses adjacent ice sheets on Antarctica’s mainland, impeding ice flow from land into water, like a cork in a bottle.

When ice shelves collapse, ice can flow faster from land into the sea, which can raise sea levels. Ice shelves all over Antarctica have been thinning, and in some cases breaking up or retreating, due to rising ocean and air temperatures. Prior observations have shown that Antarctic ice shelves can collapse suddenly and without obvious warning signs, which happened when the Larsen B ice shelf on the Antarctic Peninsula abruptly collapsed in 2002.

To better understand the physical properties of the Ross Ice Shelf, researchers buried 34 extremely sensitive seismic sensors under its snowy surface. The sensors allowed the researchers to monitor the ice shelf’s vibrations and study its structure and movements for over two years, from late 2014 to early 2017.

Ice shelves are covered in thick blankets of snow, often several meters deep, that are topped with massive snow dunes, like sand dunes in a desert. This snow layer acts like a fur coat for the underlying ice, insulating the ice below from heating and even melting when temperatures rise.

When the researchers started analyzing seismic data on the Ross Ice Shelf, they noticed something odd: Its fur coat was almost constantly vibrating.

When they looked closer at the data, they discovered winds whipping across the massive snow dunes caused the ice shelf’s snow covering to rumble, like the pounding of a colossal drum. Listen to the ice sheet’s “song” here:

They also noticed the pitch of this seismic hum changed when weather conditions altered the snow layer’s surface. They found the ice vibrated at different frequencies when strong storms rearranged the snow dunes or when the air temperatures at the surface went up or down, which changed how fast seismic waves traveled through the snow.

“It’s kind of like you’re blowing a flute, constantly, on the ice shelf,” said Julien Chaput, a geophysicist and mathematician at Colorado State University in Fort Collins and lead author of the new study published today in Geophysical Research Letters, a journal of the American Geophysical Union.

Researchers lay the conduit that connects the seismometer to the solar power system (background) and recording components at a Ross Ice Shelf seismic station. Credit: Rick Aster

Just like musicians can change the pitch of a note on a flute by altering which holes air flows through or how fast it flows, weather conditions on the ice shelf can change the frequency of its vibration by altering its dune-like topography, according to Chaput.

“Either you change the velocity of the snow by heating or cooling it, or you change where you blow on the flute, by adding or destroying dunes,” he said. “And that’s essentially the two forcing effects we can observe.”

The hum is too low in frequency to be audible to human ears, but the new findings suggest scientists could use seismic stations to continuously monitor the conditions on ice shelves in near real-time. Studying the vibrations of an ice shelf’s insulating snow jacket could give scientists a sense of how it is responding to changing climate conditions, according to Douglas MacAyeal, a glaciologist at the University of Chicago who was not connected to the new study but wrote a commentary about the findings also published today in Geophysical Research Letters.

Changes to the ice shelf’s seismic hum could indicate whether melt ponds or cracks in the ice are forming that might indicate whether the ice shelf is susceptible to breaking up.

“The response of the ice shelf tells us that we can track extremely sensitive details about it,” Chaput said. “Basically, what we have on our hands is a tool to monitor the environment, really. And its impact on the ice shelf.”

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Can You Express Your Science in 17 Syllables?

Tue, 10/16/2018 - 12:20

Lines of lyrical lucidity and true confessions of experiments gone awry: what else would a scientific haiku contest bring?

Last week, the AGU Hydrology Section Student Subcommittee challenged scientists traveling to the Fall Meeting this December to explain their research in a single haiku. The format of a haiku—a poem split between three lines, with the first line having five syllables, the second seven, and the third five—dares poets to be brief, descriptive, and profound.

Are you heading to @theAGU Fall Meeting? Tweet a haiku about your research with the tags #HaikuYourResearch and #AGU18 and the haikus with the most likes + retweets will win a prize!! Contest ends Nov 5th! pic.twitter.com/pFuGt9RGd5

— AGU Water Students (@AGU_H3S) October 3, 2018

Since the competition was unveiled last week, submissions have been pouring in via the Twitter hashtag #HaikuYourResearch. The contest is still ongoing, and the competition is fierce. Think you have what it takes?

To inspire your inner poet, we grabbed a few haikus for your reading pleasure. So fix a cup of tea, and sit back and enjoy the sweet simplicity of scientific minimalism. Then, go write your own poem! .

But Soft, What Light Through Yonder Cloud Breaks?

Clouds come high and lowIce crystals and liquid dropsReflecting sunlight #HaikuYourResearch #AGU18

— Bastiaan van Diedenhoven (@CloudsBastiaan) October 5, 2018

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Rhyming “Mass Spectrometry” Is Impressive

Forams of the seaPast is key to the presentMass spectrometry#HaikuYourResearch

— Jennifer Hertzberg (@PaleoForams) October 4, 2018

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Nothing Survives the Robot Army

Our robot armyCaptured months of flux data.R can't handle it.#AGU18 #HaikuYourResearch pic.twitter.com/QMydhfEc0V

— Holly Andrews (@HMAndrewsEco) October 5, 2018

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You Do Matter, Manganese! Don’t Let Anyone Tell You Otherwise

Arsenic UptakeIrrigation scheme matters!Manganese does, too.#HaikuYourResearch #AGU18 pic.twitter.com/zfJaleE7lJ

— Lena Abu-Ali (@LenaAbuAli1) October 4, 2018

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Can “Sounds of Dirt” Please Be a Band Name?

#HaikuYourResearch #AGU2018 Sounds bounce off of dirtLike bats, we can see the soundsSeismic for the win

— Derek Gibson (@dkgibson02) October 4, 2018

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#RealTalk

ICPMSPlease do not break down todayI must graduate#HaikuYourResearch

— Ryan Glaubke (@OcnOgrphr) October 4, 2018

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Cute Mammals to the Rescue!

Vanishing wetlandsWilderness scarred by drought, fireBeavers save the day#AGU2018 #AGU18 #HaikuYourResearch pic.twitter.com/lg2qIofvUv

— Emily Fairfax (@EmilyFairfax) October 4, 2018

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We’re Glad Yellow Was Not Included…

Colour of snowWhite, blue, brown, red even blackMelt is quicker than expected

#HaikuYourResearch #AGU18 #NationalPoetryDay

— Veronica Chan (@c_gaga) October 5, 2018

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“Think About Direction; Wonder Why You Haven’t Before”*

In the Earth's crust sitmagnetic minerals thatmess with your compass#HaikuYourResearch #AGU18

— Brian (@magnetman42) October 5, 2018

*This link is for you, millennials! .

The Symphonies of Space

Songs we can't hear playon magnetic violinsfor twirling protons. #HaikuYourResearch #AGU18 #SpaceWeather pic.twitter.com/rLtTo5tCn7

— Dr. Kristine Sigsbee (@Sputnik6400) October 9, 2018

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Devonian-ly Puzzling

The magnetic fieldDuring the DevonianWhat was it doing?#HaikuYourResearch #AGU2018

— Annique van der Boon (@Anniquevdb) October 5, 2018

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I Guess You Could Say the Lasers See the Trees for the Forest?

Laser all the trees. See how they make up the woods. Does it matter? Yes!#HaikuYourResearch

— jeff -kins(@atkinsjeff) October 6, 2018

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Ye, Plume of Old, Hark!

O plume, revealThyself! By your data andYour earthly precepts#HaikuYourResearch #AGU18https://t.co/WwlLv44MFj

— Jeremy Bennett (@driftingtides) October 5, 2018

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It’s OK, We Like Talking to Rocks Too

I speak with old rocks full of past climate’s secrets Sometimes, they share them! #HaikuYourResearch #AGU18 #Paleoclimate pic.twitter.com/eRXynxeeJO

— Fatima Husain (@FatimagulHusain) October 5, 2018

. Of course, these are just a sliver of the competition’s entries—there are oh so many more haikus tagged with #HaikuYourResearch on Twitter. Retweet or like the poems that catch your fancy to weigh in on the competition!

And if the spirit moves you, tweet your own haiku tagged with #HaikuYourResearch to give your studies the 17-syllable spotlight!

—Jenessa Duncombe (@jenessaduncombe), News Writing and Production Intern

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Arctic Sea Ice Decline Driving Ocean Phytoplankton Farther North

Tue, 10/16/2018 - 12:14

Phytoplankton blooms that form the base of the marine food web are expanding northward into ice-free waters where they have never been seen before, according to new research.

A new study based on satellite imagery of ocean color reveals phytoplankton spring blooms in the Arctic Ocean, which were previously nonexistent, are expanding northward at a rate of 1 degree of latitude per decade. Although blooms, or large explosions of phytoplankton, did not previously occur in this area, phytoplankton were present in the Arctic’s central basin at low biomass. The study also found the primary productivity of the phytoplankton, or the rate at which phytoplankton are converting sunlight into chemical energy, is increasing during the spring blooms.

The decline in Arctic sea ice over the past several decades has made way for areas of open water where phytoplankton can thrive, driving their northward expansion, according to the study’s authors. The researchers are unsure what effect this expansion will have on the food web, but the results suggest the decline of ice cover is impacting marine ecosystems in unforeseen ways.

If sea ice continues to decline, it could drive phytoplankton spring blooms farther north and increase primary productivity even more. These changes could affect the fate of the Arctic Ocean as a carbon source or a carbon sink, according to the study.

“If the ice pack totally disappears in summer, there will be consequences for the phytoplankton spring bloom,” said Sophie Renaut, a Ph.D. student at Laval University in Quebec City, Canada, and lead author of the new study in Geophysical Research Letters, a journal of the American Geophysical Union. “We cannot exactly predict how it will evolve, but we’re pretty sure there are going to be drastic consequences for the entire ecosystem.”

Phytoplankton in the Ecosystem

Phytoplankton are microscopic organisms that live in water, consume carbon dioxide and release oxygen through photosynthesis. In this process, they convert sunlight into chemical energy. Phytoplankton form the base of the marine food web, indirectly feeding everything from small fish to multi-ton whales.

Phytoplankton growth depends on the availability of carbon dioxide, sunlight, nutrients, water temperature and salinity, water depth and grazing animals, according to the NASA Earth Observatory. When conditions are ideal, phytoplankton population growth can explode, or bloom. While a bloom may last several weeks, the lifespan of an individual phytoplankton is seldom more than a few days.

Phytoplankton in the Arctic Ocean typically bloom every spring. In the past, phytoplankton blooms have been virtually absent from the highest Arctic latitudes, because these areas are usually covered by sea ice. In recent decades sea ice has declined, breaking up earlier in the spring or not forming at all in some areas of the Arctic.

In the new study, Renaut and her colleagues wanted to see if recent sea ice declines have had any effect on spring phytoplankton blooms. They used satellite observations of ocean color—which provide estimates of phytoplankton biomass and primary productivity—to track changes of the blooms each spring from 2003 to 2013.

They found the spring blooms are expanding farther north and increasing in primary productivity. In the spring and summer months, net primary productivity in the Arctic Ocean increased by 31 percent between 2003 and 2013, according to the study. The researchers also found that these blooms in the Barents and Kara Seas, north of Russia, are expanding north at a rate of 1 degree of latitude per decade.

Unexpected Effects of Sea Ice Decline Estimates of annual trends in daily flux of primary productivity (PP) during the phytoplankton spring bloom determined from satellite ocean color data. Green pixels correspond to new phytoplankton spring blooms observed since 2010. Credit: NOAA Environmental Visualization Laboratory and Geophysical Research Letters/AGU

Sea ice melt occurring earlier in the season creates larger open water areas that act as incubators for phytoplankton growth and elongate their growing season, according to Renaut.

The authors suspect spring blooms could someday extend into the Arctic’s central basin, which encompasses almost everything north of 80 degrees latitude. Primary productivity, though, would likely remain low due to a lack of nutrients. Less ice cover means spring blooms and under-ice blooms may also have to compete for light and nutrients, thus altering the flow of the marine ecosystem. The results suggest a large change in this region, which has never been free of ice cover.

“The polar regions—the Southern Ocean and the Arctic Ocean—they’re really important because they play a critical role in regulating the global climate,” Renaut said. “If sea ice disappears completely in summer in the Arctic Ocean, which is what we expect in some decades, it’s going to have an impact on the ecosystem but also likely on the climate.”

Patricia Yager, professor of Marine Sciences at the University of Georgia who was not involved with the new study, said the earlier algal bloom growth they observed in some areas could have considerable impacts if animals are not yet ready to graze on the phytoplankton.

“Such a mismatch in time could cause major changes to the Arctic food web, impacting not only the local animals and the people who live there, but also the global population of migrating animals who depend on these Arctic resources,” Yager said. “What happens in the Arctic does not stay in the Arctic.”

Cecile Rousseaux, a research scientist at the Universities Space Research Association, who was not involved in the new study, said the study advances research in this area by investigating individual regions of the Arctic for phytoplankton productivity, and represents evidence of the effects that reduced ice cover have on the biochemical cycle of the Arctic Ocean. However, Rousseaux noted that the study does have limitations.

“It is also important to remember that we are currently limited by the amount of data available to study these changes,” Rousseaux said. Longer time series of satellite data will allow us to confirm whether these trends in phytoplankton productivity

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Long-term Dataset Reveals How Management Affects River Biology

Tue, 10/16/2018 - 12:13

The Murray-Darling Basin in South Australia, like many of Earth’s major river systems, is an important source of water resources for agricultural use, and urban water supply. It also sustains natural communities of macroinvertebrates, such as insects, crustaceans, and mussels.

River flow is sustained by groundwater that has accumulated a high salt content over millennia because of low rainfall rates and high rates of evapotranspiration (or water lost to the atmosphere). Irrigated agriculture has raised groundwater table levels, resulting in increased inputs of saline groundwater into the Murray River. This has posed a health risk to humans, while flood management and the effects of agriculture on river water chemistry have impacted the macroinvertebrates.

Paul et al. [2018] include an analysis of an impressive dataset collected over a 33-year study of water chemistry and biology along the 2,300-kilometer length of the Murray River. The data are rich in terms of both temporal and spatial coverage of species, hydrology, and groundwater chemistry (i.e., salinity), and provides new insights on the effects of land management on river systems and their biology. Among other findings from this work is a better understanding of the roles played by salinity reduction on restoring the biological health of the river. The results address globally important issues in water research—floods, droughts, salinity, and management of large river systems.

Citation: Paul, W. L., Cook, R. A., Suter, P. J., Clarke, K. R., Shackleton, M. E., McInerney, P. J., & Hawking, J. H. [2018]. Long‐term Monitoring of Macroinvertebrate Communities Over 2,300 km of the Murray River Reveals Ecological Signs of Salinity Mitigation Against a Backdrop of Climate Variability. Water Resources Research, 54. https://doi.org/10.1029/2018WR022976

—D. Scott Mackay, Editor, Water Resources Research

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How Do We Accomplish System Science in Space?

Mon, 10/15/2018 - 12:07

“When hoping to understand the behaviors of a complex system, one needs to analyze not only how different components work together to form the behaviors of the whole system but also the behaviors of the individual parts. Without deep and specific comprehension of the behaviors of the individual parts, there will be no way to capture the behaviors of the complex system.”

These words, from Systems Science: Methodological Approaches by Yi Lin et al., summarize the ethos of the Exploring Systems-Science Techniques for the Earth’s Magnetosphere-Ionosphere-Thermosphere meeting held this summer. The meeting took on the task of characterizing the current state of the study of Earth’s space environment and defining future directions for the system science approach.

To foster an environment with an appropriate diversity of expertise, the 26 participants came together from a group of disparate scientific disciplines: plasma physics, magnetosphere-ionosphere-thermosphere (M-I-T) science, space systems engineering, big data analytics, complex systems research, applied mathematics, and data science.

An interdisciplinary group was charged with assessing the current state, future needs, and means to progress “system science” for the M-I-T system.This interdisciplinary group was charged by the organizing Space Science Institute to assess the current state, future needs, and means to progress “system science” for the M-I-T system. Three provocative questions were posed to the leaders in attendance:

What are the system properties of the M-I-T system? What new mathematical techniques and methodologies are required to progress M-I-T system science? In the context of funding, observational limitations, and the advent of sophisticated new tools to perform data-driven discovery, how can M-I-T system science be advanced?

The outcome was a rich conversation, taking place across the 3-day meeting, about previous efforts, current challenges, and new ideas to accomplish M-I-T system science. Discussions were organically structured around three topics in particular: (1) coupled modeling, (2) statistical inference, and (3) system complexity.

Participants embraced these themes and created a new definition for system science (see Figure 1). Despite being only one possible arrangement of system science, it provided a useful foundation on which to build an understanding of the current capabilities and shortcomings of M-I-T system science and new areas of need (e.g., the intersection of statistical inference, perhaps in the form of machine learning, and coupled models). The group reached several conclusions:

Sophisticated tools from the field of data science will allow researchers to use available data to study the M-I-T system in new, comprehensive ways. Existing observational capabilities must be augmented, emerging technologies must be tapped, and innovative approaches must be explored. New funding avenues, likely accessed through interdisciplinary collaborations, must be embraced to progress M-I-T system science. The term “integrative science” was used during discussions as a call for thinking about the entire system, integrating across the disciplines, and using a diversity of techniques. Fig. 1. One possible presentational arrangement for system science. Embedded within the NASA Heliophysics System Observatory and related observing networks are coupled models (blue), complexity (red), and statistical inference (green). Each is a critical component to accomplish system science. Credit: Nick Watkins, Jeff Thayer, and Ryan McGranaghan

The outcomes of the meeting, particularly a new possible definition for system science, have a resounding message across scientific disciplines, reaching beyond the M-I-T system.

—Ryan McGranaghan (email: ryan.mcgranaghan@jpl.nasa.gov), University Corporation for Atmospheric Research, Boulder, Colo.; also at NASA Jet Propulsion Laboratory, Pasadena, Calif.; Joseph E. Borovsky, Space Science Institute, Boulder, Colo.; and Michael Denton, Space Science Institute, Boulder, Colo.

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Roger G. Barry (1935–2018)

Mon, 10/15/2018 - 12:07

Roger G. Barry died in Louisville, Colo., on 19 March 2018 at the age of 82.

Roger was a key figure in the development of scientific data stewardship, from its first halting steps to petabyte-scale archives at data centers.Roger’s career spanned more than 60 years, from the International Geophysical Year in 1957–1958 through the fourth International Polar Year in 2007–2009 and beyond. He contributed to widely diverse areas of cryospheric research, from paleoclimatology to the analysis of satellite data and modeling.

One of Roger’s greatest legacies is that he was a key figure in the development of scientific data stewardship, from its first halting steps to petabyte-scale archives at data centers. He also received numerous national and international fellowships and awards over his career and played central roles in major climate programs, including at the World Meteorological Organization (WMO) and on the Polar Research Board of the National Academy of Sciences.

Early Work and the Power of Computing

Roger began his career in England, receiving a bachelor of arts with honors in geography from the University of Liverpool in 1957. Subsequently, he conducted climatological research in Labrador, Canada, before obtaining a M.Sc. in geography from McGill University in 1959 and a Ph.D. in climatology from the University of Southampton in 1965. He then joined the University of Colorado Boulder (CU Boulder), where he served as an associate professor and then as a professor of geography at the university’s Institute of Arctic and Alpine Research from 1968 to 1980. He served at the university’s Cooperative Institute for Research in Environmental Sciences from 1980 to 2018.

During the 1960s, he was instrumental in defining the new field of synoptic climatology, marking a transition from description to explanation.Roger was among the first to recognize the value of computers for processing and storing Earth science data; one of his earliest papers described the potential uses of punched cards for analyzing geographic data. During the 1960s, he was instrumental in bringing scaling concepts into climatology and in defining the new field of synoptic climatology, marking a transition from description to explanation.

Other early work focused on Arctic water vapor fluxes, which Roger later extended to the global hydrological cycle. Scientists recognized the implications of this research for late Pleistocene glaciation, and Roger and colleagues at the National Center for Atmospheric Research (NCAR) were the first to apply a global climate model to simulate ice age climate.

Subsequent work included sea ice–climate interactions and polar amplification (the intensification of climate change effects near Earth’s poles). He also did extensive research on the mountain climates of the Colorado Rockies, tropical New Guinea, and Venezuelan Andes, including modeling the spatial distribution of solar radiation and precipitation at high elevations.

Sharing Cryospheric Data Around the World

“Roger, as one of the pioneers of numerical climatology, had the recording and preservation of data in his DNA, inculcated this in his students, and this ethos found a ‘permanent’ life as the NSIDC.”Roger was the founding director of the National Snow and Ice Data Center (NSIDC) from 1982 until 2008. Ellsworth LeDrew, one of Roger’s students, now at Canada’s University of Waterloo, recalled Roger’s role in establishing this center: “Roger, as one of the pioneers of numerical climatology, had the recording and preservation of data in his DNA, inculcated this in his students, and this ethos found a ‘permanent’ life as the NSIDC.”

NSIDC’s roots were the World Data Center (WDC) A for Glaciology, which moved to CU Boulder in 1976. NSIDC, which grew under Roger’s leadership into a center with a multimillion-dollar budget each year, archives and distribute petabytes of cryospheric data. A major step in this evolution came in 1993 when NSIDC became the host for the NASA Snow and Ice Distributed Active Archive Center, charged with managing cryosphere-related remote sensing data collected during NASA’s Earth Observing System (EOS) missions.

Even before the EOS missions, Roger had recognized the importance of earlier satellite passive microwave data. This data series, which continues to this day, is the source of time series of sea ice and snow cover and ice sheet surface melt—key indicators of climate change.

Roger promoted collaborative international research and data exchange through founding roles in programs like the WMO Global Digital Sea Ice Data Bank and the World Climate Research Programme’s Climate and Cryosphere project. Early in his career, Roger learned Russian through a BBC radio program. From the mid-1980s to the mid-2000s, NSIDC/WDC hosted several Russian scientists. Roger’s numerous visits to Russia during the 1990s paved the way for several data exchange projects. A visit to China helped establish the WDC for Glaciology in Lanzhou. All of these collaborations were aided by his fluency in Russian, German, and French, as well as conversational Chinese, Spanish, and Italian.

Teaching the Next Generation of Scientists (and the Next…)

Over the course of his career, Roger advised more than 50 graduate students (36 received Ph.D.’s) and postdoctoral research scientists covering diverse aspects of the climate system. Many have gone on to distinguished careers. All of his students and colleagues have benefited from Roger’s encyclopedic knowledge. Roger was an ardent supporter of gender equality in science. His recognition and kindness also reassured many starting scientists and support staff that they had made the right career choice.

Beyond his students, postdocs, and support staff, Roger influenced many more researchers through his numerous textbooks on the cryosphere and the climate. His first book, Atmosphere, Weather and Climate, published with coauthor Richard Chorley in 1968, is now in its ninth edition. Other textbooks include Mountain Weather and Climate, The Arctic Climate System (with coauthor Mark Serreze), and, most recently, The Global Cryosphere: Past, Present and Future (with coauthor Thian Yew Gan; the second edition is to be published in 2019–2020).

An Active Late Career

Following his retirement from CU Boulder, Roger remained active, writing, traveling, and contributing to the scientific community. He served as director of the World Climate Research Programme’s International Climate Variability and Predictability (CLIVAR) project office from August 2012 to March 2014.

He continued to attend scientific meetings, often using his encyclopedic memory to bring relevant references to the presenter’s attention. In early March 2018, he was still reading proofs of his now-published book Polar Environments and Global Change (coauthored with Eileen McKim).

“Persevere with what you consider to be important; continually retool your techniques; know who is doing what…network with others of the clan!”In one of his last papers, Roger reflected on his more than half century in climate science. Through the paper, he offered this advice to “third-generation” students: “persevere with what you consider to be important; continually retool your techniques; know who is doing what, not only in the English-speaking world, but internationally; network with others of the clan!”

We thank Konrad Steffen, Ellsworth LeDrew, Mark C. Serreze, Mark Parsons, Roger S. Pulwarty, Andrew Carleton, and Jack D. Ives for their contributions to this article.

Ronald L. S. Weaver, Walt Meier (email: walt@nsidc.org), and Florence Fetterer, National Snow and Ice Data Center, Boulder, Colo.

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2018 AGU Election Statistics

Mon, 10/15/2018 - 12:06

In its most recent biennial election, for which voting ended last month, AGU membership chose 57 new leaders to serve 2-year terms in 2019–2020. Union officers, Board members, section officers, and student and early-career representatives to the Council were elected. Here the AGU Leadership Development/Governance Committee takes a look back at the voting this year and how 2018 stacked up in comparison to prior elections.

See the accompanying Eos.org article entitled “Lozier to Be AGU President-Elect/AGU Leadership Transitions” for election results and an overview of the leadership transition that’s now getting started.

Electronic Voting

Members voted electronically, and access to voting was provided to all eligible voters for a period of 30 days. All members who joined or renewed their membership by 13 August 2018 were eligible to vote in this year’s leadership election.

Survey and Ballot Systems, Inc. (SBS) conducted the voting. SBS, which offers election planning and management services, provided unique login links and other support services for eligible voters throughout the election. On 27 September, the company certified the results, which were then reviewed by the AGU Leadership Development/Governance Committee.

Participation Rate Tops 20%

More than 89% of voters continue to be satisfied or very satisfied with the voting process. Voters provided many comments and suggestions, which AGU will analyze and discuss over the coming weeks.The total number of ballots validated in the election was 9,141. The number of eligible voters was 45,491, making the participation rate 20.09%. This is slightly lower than in AGU’s last election in 2016 in which the participation rate was 21.13%.

SBS provided all voters the opportunity to rate their satisfaction with the 2018 voting process. In response to this election, 4,259 comments were received. This is a good indication of voter engagement, and 89.5% of voters continue to be satisfied or very satisfied with the voting process. Voters provided many comments and suggestions, which AGU will analyze and discuss over the coming weeks. Voter feedback is very important, and comments received in 2016 were instrumental in helping the Leadership Development/Governance Committee plan for the 2018 election.

Getting the Word Out

The election was supported by articles in Eos.org and other communications throughout this year. The Leadership Development/Governance Committee published the proposed slate in Eos.org on 7 June and the final slate on 17 July.

A special election website was created to aid members with the voting process. Promotion of the election included the AGUniverse newsletter, Eos print ads, Eos Buzz ads, the AGU home page carousel, Facebook, Twitter, and emails. The election vendor sent reminder emails to eligible voters throughout the election, as did section leaders.

Notifications

The Leadership Development/Governance Committee expresses its gratitude to all candidates and to all AGU members who voted.After reviewing the election report provided by SBS, the committee kicked off the process to notify candidates and announce the results. The process required that all 114 candidates be notified before the election results could be publicly announced. Each of the 23 sections participating in the 2018 election provided a single point of contact to receive results and contact candidates. Leadership Development/Governance Committee members contacted Board candidates and the student and early-career candidates. Results were released online on 10 October 2018.

The Leadership Development/Governance Committee expresses its gratitude to all candidates and to all AGU members who voted.

—Leadership Development/Governance Committee: Margaret Leinen (Chair; email: AGU_Governance@agu.org), Robert A. Duce, Luis Gonzalez, Hans Lechner, Catherine McCammon, Jim Pizzuto, Sabine Stanley, George Tsoflias, Vaughan Turekian, Tong Zhu, Chris McEntee, and Cheryl Enderlein

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Lozier to Be AGU President-Elect/AGU Leadership Transitions

Mon, 10/15/2018 - 12:05

AGU members have elected physical oceanographer Susan Lozier as the organization’s next president-elect, as well as 56 other Union officers, Board members, section officers, and student and early-career representatives to the AGU Council for the 2019–2020 leadership term.

In voting that ended on 25 September, Lozier, a distinguished professor at Duke University’s Nicholas School of the Environment in Durham, N.C., was chosen to serve a 2-year term as president-elect starting in 2019, after which she will become AGU president in 2021. A renowned oceanographer, Lozier leads an international research program on the ocean’s overturning circulation and has pioneered mentoring programs for early-career scientists, particularly women, in the geosciences.

Lozier and other newly elected leaders will take office on 1 January 2019, and about half of the current AGU Board and Council members will rotate off. New members of the Council Leadership Team will be elected after the first of the year, and committees and task forces will continue their work in support of AGU’s mission and the Board and Council work plan.

An accompanying Eos.org article by the AGU Leadership Development/Governance Committee, entitled “2018 AGU Election Statistics,” discusses the participation, timing, communications, and other details of this year’s election process.

Planning for the 2019–2020 Term

Members who volunteer can make a real difference. It is rewarding work to advance AGU’s mission and vision in collaboration with colleagues from around the world.Newly elected Board and Council members will start orienting to their roles in the next few weeks and will observe the December 2018 Board or Council meetings before taking office in the new year. Continuing Board and Council members will join new members for leadership orientation in the first quarter of 2019.

Members who volunteer can make a real difference. It is rewarding work to advance AGU’s mission and vision in collaboration with colleagues from around the world. In addition to Board and Council positions, there are many volunteer opportunities for member participation in sections and Union-level committees and task forces. Time commitment depends on specific roles and responsibilities. Best of all, volunteering for AGU offers you a chance to work with other leaders, develop new skills, and influence the Earth and space science community. Watch for more information about how to volunteer in the weeks ahead.

Newly Elected Officers

The Leadership Development/Governance Committee is pleased to announce the newly elected members of the AGU Board and Council. Please join us in congratulating these incoming leaders, who will begin their 2-year terms on 1 January 2019.

AGU Board of Directors

President-elect: Susan Lozier General Secretary: Jana Davis International Secretary: Carlos Nobre Director, Position 1: Richard “Rick” Murray Director, Position 2: Jill L. Karsten Director, Position 3: Jenny Riker 

Council: Student and Early Career

Student, Position 1: Paige Martin Student, Position 2:  Joshua R. Jones Student, Position 3: Antonio Meira Early Career, Position 1: Rosie L. Oakes

AGU Sections

Atmospheric and Space Electricity President-elect: Morris Cohen Secretary: Sonja A. Behnke 

Atmospheric Sciences President-elect: Paul A. Newman Secretary, Physics, Dynamics and Climate: Susan C. van den Heever

Biogeosciences President-elect: Margaret S. Torn Secretary: Jennifer Pett-Ridge

Cryosphere President-elect: Michele Koppes Secretary: Peter Neff

Earth and Planetary Surface Processes President-elect: Gordon E. Grant

Earth and Space Science Informatics President-elect: Jeff de La Beaujardière Secretary: Sarah Ramdeen

Geodesy President-elect: Anny Cazenave Secretary: Jennifer Susan Haase

Geomagnetism and Paleomagnetism President-elect: France Lagroix Secretary: Ioan Lascu

Global Environmental Change President-elect: Julie Brigham-Grette Secretary: Wenhong Li

Hydrology President-elect: Ana Barros

Mineral and Rock Physics President-elect: Sébastien Merkel Secretary: Jin Zhang

Natural Hazards President-elect: Dalia Kirschbaum Secretary: Suzana J. Camargo

Near-Surface Geophysics President-elect: Burke J. Minsley Secretary: Kisa Mwakanyamale

Nonlinear Geophysics President-elect: Juan M. Restrepo Secretary: Raffaele Marino

Ocean Sciences President-elect: Clare E. Reimers Secretary, Biological Oceanography: Kendra Daly Secretary, Physical Oceanography: Janet Sprintall

Paleoceanography and Paleoclimatology President-elect: Ingrid Hendy Secretary: Branwen Williams

Planetary Sciences President-elect: Michael Mischna Secretary: David A. Williams

Seismology President-elect: Suzan van der Lee Secretary: Heather DeShon

Societal Impacts and Policy Sciences President-elect: Julie Vano Secretary: Maya K. Buchanan

Space Physics and Aeronomy President-elect: Geoff Reeves Secretary, Aeronomy: Romina Nikoukar Secretary, Solar and Heliospheric Physics: Christina O. Lee

Study of the Earth’s Deep Interior President-elect: Kanani K. M. Lee Secretary: Jessica Irving

Tectonophysics President-elect: Jean-Philippe Avouac Secretary: Suzanne Carbotte

Volcanology, Geochemistry, and Petrology President-elect: Dominique Weis Secretary, Geochemistry: Matt Jackson Secretary, Volcanology and Petrology: Christy Till

Continuing Board Members

As many new leaders join AGU’s governance structure on 1 January, others will continue in their current offices for 2019–2020 or assume new roles according to the succession rules specified in the AGU bylaws. Current president-elect Robin Bell will become AGU president and will chair the Board of Directors and the Executive Committee. Now AGU president Eric Davidson will become past president and serve as chair of the Leadership Development/Governance Committee.

AGU established a Board rotation strategy to ensure leadership continuity from term to term. The goal is to carry over about half of the elected positions. Those continuing for 2019–2020 will be President Bell and Past President Davidson; Board members Chris Ballentine, Lisa Graumlich, and Kerstin Lehnert; and Executive Director/CEO Chris McEntee. Four additional Board positions will be selected or reappointed by early next year: chair of the Development Board, vice chair of the Council, and two at-large members.

Continuing Council Leaders

As incoming president-elect, Susan Lozier will chair the AGU Council. A new Council Leadership Team will be elected by Council members after the first of the year to assist her in leading the Council. Bell and McEntee will remain as Council members to help ensure a smooth leadership transition. Also continuing to serve on the AGU Council will be early-career representatives Catalina Oaida and Tim van Emmerik, together with current section presidents-elect who move up to serve as presidents:

Maribeth Stolzenburg, Atmospheric and Space Electricity James Hurrell, Atmospheric Sciences Elise Pendall, Biogeosciences Lora Koenig, Cryosphere Dorothy Merritts, Earth and Planetary Surface Processes Denise Hills, Earth and Space Science Informatics M. Meghan Miller, Geodesy Catherine Johnson, Geomagnetism, Paleomagnetism, and Electromagnetism Philip Mote, Global Environmental Change Scott Tyler, Hydrology Wenlu Zhu, Mineral and Rock Physics Seth Stein, Natural Hazards Xavier Comas, Near-Surface Geophysics Sarah Tebbens, Nonlinear Geophysics Bob Anderson, Ocean Sciences Petra Dekens, Paleoceanography and Paleoclimatology Rosaly Lopes, Planetary Sciences Anne Sheehan, Seismology Maggie Walser, Societal Impacts and Policy Sciences Christina Cohen, Space Physics and Aeronomy Scott King, Study of the Earth’s Deep Interior Julia Morgan, Tectonophysics Michael Manga, Volcanology, Geochemistry, and Petrology

The current leaders for the GeoHealth section will continue to serve on the AGU Council, and the newly appointed leaders for the Education section will join the Council immediately. These two new sections will elect leaders in the 2020 AGU election.

This is a great time to be involved in AGU as 2019 is AGU’s Centennial year and will offer people around the world new opportunities to engage with science.Aubrey Miller, GeoHealth president Claire Horwell, Geohealth president-elect Mark Moldwin, Education president Tanya Furman, Education president-elect

Joining these presidents and presidents-elect are

Ben Zaitchik, GeoHealth Secretary Vincent Tong, Education Secretary

This is a great time to be involved in AGU as 2019 is AGU’s Centennial year and will offer people around the world new opportunities to engage with science. AGU continues to lead in many ways: making scientific data open and accessible, growing a diverse and inclusive workforce, accelerating the exchange of scientific knowledge, making a positive societal impact, evolving governance excellence and mission-aligned financial stewardship, practicing organizational adaptation, and renovating a headquarters building that lives our values.

Congratulations to these newly elected volunteer leaders and thanks to all members who volunteer their time and talents to AGU.

—Margaret Leinen (email: AGU_Governance@agu.org), Past President and Leadership Development/Governance Committee Chair, AGU

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Hydrology Dictates Fate of Carbon from Northern Hardwood Forests

Fri, 10/12/2018 - 11:45

From forested coastal wetlands to northern boreal forests, forests are considered essential cogs in the global carbon cycle. Generally, forests act as “sinks” by absorbing more carbon from the atmosphere through photosynthesis than they release, but they still do emit a considerable amount of carbon dioxide. Much of this release happens through respiration by soil microbes.

However, not all carbon lost by forests escapes to the atmosphere: A small but significant amount is exported into aquatic systems via dissolved organic carbon, which derives from soil material like plant litter and peat. Compared to atmospheric carbon export, aquatic export is small, but it is still considered a critical carbon flux.

In a new study, Senar et al. investigated how hydrologic connectivity controls carbon transport in the ecosystem and how carbon is partitioned between the atmosphere and waterways in Canada’s northern hardwood forests. The researchers hypothesized that hydrologic connectivity—the water-mediated transfer of matter and energy between landscape positions—determines carbon’s fate in the ecosystem. The flow of water between habitat types is closely tied to soil moisture, water table depth, and stream discharge.

The research took place in the Turkey Lakes Watershed, an experimental watershed located approximately 60 kilometers north of Sault Ste. Marie, Ontario, Canada. The researchers collected stream samples for 5 years to monitor dissolved organic carbon, and they monitored carbon dioxide emissions using flux chambers placed across habitat types. Other measurements included soil temperature, moisture, and organic carbon.

The results indicated that hydrologic connectivity between uplands, ecotones (regions of transition), and wetland habitats does indeed control the fate of carbon—both atmospheric and aquatic—in the northern hardwood forest; however, the study unexpectedly found that hydrological connectivity also dictates the magnitude of carbon exported from the ecosystem. In water-limited habitats, like uplands, the increase in soil water stimulated microbial activity and, subsequently, carbon dioxide released from respiration. In contrast, as wetlands and other water-saturated areas became hydrologically linked to the surrounding uplands, the increase in soil water tamped down the soil bacteria liveliness in the resulting anaerobic soils.

The study also found that hydrologically connected habitats resulted in an increase in aquatic transport of carbon. In other words, as more water entered the ecosystem, more carbon washed downstream into streams and lakes. The findings showed a distinct seasonal pattern, with increased aquatic transport during periods of high hydrologic connectivity, namely, spring snowmelts and fall storms.

Future climate predictions project a trend toward higher temperatures and prolonged periods of disconnected hydrology. The authors suggest that under those circumstances, northern hardwood forests will initially increase atmospheric carbon emissions from upland and ecotone habitats, with an eventual decrease as water becomes limited. The reduction in hydrologic connectivity will also result in less aquatic carbon transport downstream. (Journal of Geophysical Research: Biogeosciences, https://doi.org/10.1029/2018JG004468, 2018)

—Aaron Sidder, Freelance Writer

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Subsurface Imaging Sheds Light on Dead Sea Sinkholes

Fri, 10/12/2018 - 11:43

On 3 January 1998, an 8-meter-deep sinkhole suddenly opened up at a campsite bordering the Dead Sea, swallowing up a member of the camp’s staff. Since then, thousands of other sinkholes have developed in the area—a matter of great concern in this region, which draws tourists seeking to stand at Earth’s lowest point on land and float in water 10 times saltier than the oceans.

These maws, some of which are several tens of meters in diameter, have destroyed numerous buildings and roads and have forced local farmers to abandon their fruit orchards. Researchers now have used seismic waves to study an area near the southeastern tip of the Dead Sea that is riddled with sinkholes. They showed that the layering of buried sediments, rather than a thick band of salt, as was previously thought, likely predisposes the region to sinkhole formation.

An Artificial Earthquake

“Suddenly sinkholes appear. It’s a big problem.”Sinkholes around the Dead Sea are not just destructive, explained Hussam Alrshdan, a geophysicist at the Ministry of Energy and Mineral Resources in Amman, Jordan. They’re also unpredictable. “Suddenly sinkholes appear,” he said. “It’s a big problem.”

In this new study, Alrshdan and his colleagues relied on a technique called shear wave reflection seismic imaging to trace how materials like clay, silt, salt, and sediments were layered in an alluvial fan near Ghor Al-Haditha, Jordan. Using a wheelbarrow-mounted vibrating source, the scientists launched seismic waves into Earth. “It’s an artificial earthquake,” Alrshdan said of the method.

These waves penetrated to a depth of roughly 200 meters. Seismic waves travel through different materials with different telltale velocities. By studying how quickly the waves propagated underground before being picked up again by seismic receivers positioned some distance away, the researchers could, in essence, take an “ultrasound” of the buried material.

With this ultrasound, Alrshdan and his colleagues inferred the composition and layering of the material in the alluvial fan with meter-scale resolution. Although the researchers studied only this one alluvial fan, these features are found around the Dead Sea in other areas characterized by sinkholes, the team noted.

“We were surprised that we didn’t find any salt layer.”One finding immediately stood out in the data. “We were surprised that we didn’t find any salt layer,” said Alrshdan. Previously, scientists studying the Dead Sea had suggested that a 2- to 10-meter layer of compacted salt lay roughly 40 meters below the surface. This salt, the reasoning went, played a key role in sinkhole formation: As freshwater runoff down nearby valleys slowly eroded this layer, it would weaken and produce cavities that eventually would turn into sinkholes.

But Alrshdan and his colleagues didn’t find any evidence of salt: The seismic wave speeds they recorded were several times slower than what would be expected if salt were present. Furthermore, two boreholes drilled in Ghor Al-Haditha down to 45 and 51 meters, respectively, showed no evidence of a salt layer. What then was responsible for the numerous sinkholes pockmarking the area, the team wondered?

Weakening Layers

Water washed away fine-grained sediments like sand from the upper layers of the ground, weakening those layers’ structure.The researchers found their answer in their seismic imaging, which showed regions that reflected seismic waves poorly. Instead of forming compact, ordered layers, the material in these areas was “loosening and cracking,” the team reported late last month in Solid Earth. The team hypothesized that water washed away fine-grained sediments like sand from the upper layers of the ground, weakening those layers’ structure. Over time, as these sediments were transported to the Dead Sea, they would leave behind an increasingly porous matrix of coarser materials—gravels and boulders—that would eventually give way and create a sinkhole, Alrshdan and his colleagues proposed.

The results indicate that shear wave reflection seismic imaging can be applied to help determine the factors that help form sinkholes in other settings and at other locations, noted Pauline Kruiver, a geophysicist at Deltares, an independent research institute in the Netherlands, who was not involved in this work.

On a more immediate level, this research is important for ensuring that future construction projects in the Dead Sea region aren’t built on sinkhole-prone ground, said Alrshdan. He knows that he and his team can’t stop nature; all of this work, Alrshdan says, is to help people “live in peace with these sinkholes.”

—Katherine Kornei (email: hobbies4kk@gmail.com; @katherinekornei), Freelance Science Journalist

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Mentoring365: New and Improved Mentoring Interface

Thu, 10/11/2018 - 20:17

As AGU embarks upon its Centennial, both reflecting back on a century of discoveries, innovations, solutions, and collaborations and looking forward to the next century of exciting possibilities, it is clear that our mission to promote discovery in Earth and space science for the benefit of humanity will soon rest in the hands of the next generation of scientists. Mentorship provides a critical opportunity for professionals at any stage.What will that generation of scientists look like, and what challenges will they face?

Mentorship provides a critical opportunity for professionals at any stage to learn from the insights and experiences of established scientists as they navigate their careers and define their professional goals. To help enable a diverse community of Earth and space scientists to succeed in their chosen fields, AGU and its partners, the Society of Exploration Geophysicists, the Association for Women Geoscientists, the American Meteorological Society, and the Incorporated Research Institutions for Seismology, are proud to announce a suite of new enhancements to the successful Mentoring365 program.

Mentoring That Transcends Boundaries

Mentoring opportunities can often be inaccessible to many because of socioeconomic constraints, limited local scientific networks, or an inability to attend annual society meetings where professional relationships are often forged. Enter Mentoring365.Key to the program’s success is its ability to transcend geographic boundaries.

First launched in 2017, Mentoring365 is a year-round program that brings together early- and advanced-career Earth and space scientists to help facilitate the sharing of professional knowledge, expertise, skills, and insights. So far, the program has already matched 168 mentors and mentees via its online platform. Key to the program’s success is its ability to transcend geographic boundaries. More than half of mentees (51%) and 38% of mentors came from outside the United States. Furthermore, nearly two thirds of mentees chose a mentor from a different country, helping connect scientists from all over the world.

Improved Facilitation of Mentorship The new interface makes it easy to find your match in the Mentoring365 community. Credit: AGU

Now, a year after its inception, Mentoring365 is getting an upgrade. The improved platform offers a more diverse mentor pool with expertise spanning industry, academia, and government. The new Mentoring365 platform uses algorithms to match mentees with scientists whose research interests and mentoring goals more closely align with their own. The update also offers in-platform messaging and a mobile app. Additionally, mentors and mentees can track progress toward goals and receive messages from Mentoring365 that help enhance resource sharing and discussion facilitation.

Free to all members of the Mentoring365 partner societies, the improved platform creates a high-impact sharing experience that will prove vital in ensuring that the geosciences promote an increasingly inclusive, interconnected, and knowledgeable workforce prepared to face the challenges of the next 100 years.

Give Back to the Scientific Community

The effectiveness of our science on the world around us, including economic, environmental, and human health conditions around the globe, will depend upon growing a diverse and inclusive community of researchers.If you are an early-career scientist looking for career guidance in your field or if you are an experienced Earth and space scientist looking to give back to your scientific community, I hope that you will consider becoming a part of Mentoring365. The effectiveness of our science on the world around us, including economic, environmental, and human health conditions around the globe, will depend upon growing a diverse and inclusive community of researchers ready to lead the way. There is more to this transition than simply passing a baton across generations. Effective mentoring can help open doors to new possibilities for a new generation of scientists to lead us into our next century of scientific discovery for the benefit of humanity.

—Eric A. Davidson (email: president@agu.org), President, AGU

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Analysts Forecast Midterm Election’s Impact on Climate Change

Thu, 10/11/2018 - 12:53

If Democrats take back majority control of the House of Representatives in the midterm election on 6 November, it could be a mixed bag for climate change efforts in Congress, according to policy experts at a recent forum.

A predicted blue wave, with Democrats capturing the House, could bring a lot more focus on climate change and on oversight of the Trump administration, analysts said at an election-themed forum at the Society of Environmental Journalists’ annual conference in Flint, Mich., on 5 October. However, a significant loss of moderate Republicans could chill bipartisan efforts on climate change, the panelists indicated.

If Democrats win one of the two chambers of Congress, “climate change will no longer be a four-letter word.”If Democrats win one of the two chambers of Congress, “climate change will no longer be a four-letter word,” said panelist Ana Unruh Cohen, managing director of government affairs for the Natural Resources Defense Council’s (NRDC) Action Fund. The fund builds political support for the goals of NRDC, an environmental group headquartered in New York. “We’ll be back to actually talking about it.”

If Democrats do, in fact, take the House, Cohen said that she anticipates they will likely introduce various pieces of legislation to deal with climate change, whether the bills focus on a carbon tax, caps for greenhouse gas emissions coupled with a market for trading emissions allowances (cap and trade), energy, or a more comprehensive approach to the issue.

“Climate change is a multifaceted problem, and it requires many different types of solutions,” Cohen, the former policy director for climate, energy, and natural resources for Sen. Ed Markey (D-Mass.), said. “If you think about baseball for a moment, you’ve got to hit some singles and doubles to load the bases for a grand slam. So that’s what, legislatively, people will be looking to do: to build some smaller policies up to take the time to rebuild people’s understanding of the urgency of addressing climate change.”

Even if climate-related bills do not see a lot of movement in the current political scene, they “could be important building blocks for later action,” she added.

A Plug for a Carbon Tax

A tax on carbon could be a winner, explained panelist Alex Flint, executive director of the Washington, D. C.–based Alliance for Market Solutions, which favors a carbon tax policy consistent with a progrowth conservative agenda. Such a tax, he said, would help to curb greenhouse gas emissions while using the money for other priorities.

“One of the best ways to address the large-scale change in the economy that has to occur to reduce greenhouse gas emissions is not to make it just a discussion about greenhouse gas emissions,” said Flint, who was a member of President Trump’s transition team. He said that a “reasonable” carbon tax of $30–$50 per ton of greenhouse gases could raise $1.5 trillion over 10 years and that the proceeds could go to shortfalls in the Highway Trust Fund and other areas.

Could Bipartisan Efforts on Climate Change Be Weakened?

“If we agree that we really need to solve climate at a scale for the duration, our contention is that we need both parties involved.”Flint and Cohen both said that they worry about what might happen to the bipartisan House Climate Solutions Caucus if a number of moderate Republican representatives lose their seats in the election. The caucus, which currently has 90 House members and advocates for a bipartisan approach to dealing with climate change, includes many Republicans who “have been among the first to reconsider the Republican orthodoxy,” Flint said.

“If we agree that we really need to solve climate at a scale for the duration, our contention is that we need both parties involved,” he said. “We need to somehow make it safe for Republicans to take initial steps to join the [caucus] even if it doesn’t take any action, but at least because they recognize they need a fig leaf on this.”

Flint forecast that there will be “a lot of turnover” on the caucus after the election. The caucus is going to have to decide what to do going forward, including whether to maintain its balance of having an equal number of Republican and Democratic members, he added.

Will Trump Deal with Democrats?

At a federal level, passage of climate change legislation rests to a large extent on President Trump, whose administration has been combing through environmental regulations passed during the Obama administration with an intent “to undermine them,” Cohen said.“It’s hard for me to see the president really be willing to engage in negotiations with Democrats. But he did write The Art of the Deal.”

A lot depends on how President Trump “responds to what I anticipate will be some pretty vigorous oversight by Democratic [committee] chairs of his administration,” she said, adding, “it’s hard for me to see the president really be willing to engage in negotiations with Democrats. But he did write The Art of the Deal.”

—Randy Showstack (@RandyShowstack), Staff Writer

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