EOS

Syndicate content Eos
Science News by AGU
Updated: 1 day 1 hour ago

Space Traffic Management: Better Space Weather Forecasts Needed

Thu, 02/27/2020 - 12:30

As our use of satellite applications increases (and hence the number of satellites in orbit increases), there is growing recognition, around the world, of the need for space traffic management, i.e. technical and regulatory provisions that promote the safe launch, operation, and return to Earth of satellites.

Space weather is an important element of the technical provisions because of its many impacts on satellite operations. One of these impacts is to drive changes in the density of the upper atmosphere (the thermosphere), leading to significant uncertainties in forecasts of satellite atmospheric drag and, hence, in the forecast position of satellites in low Earth orbit. These uncertainties can make it difficult to assess the risk of satellite collisions in this increasingly busy region of space.

Berger et al. [2020] provide a call-to-arms for research that will improve our ability to forecast changes in the density of the thermosphere, especially during geomagnetic storms. This will allow more nuanced assessment of collision risks, enabling all concerned with future space traffic management (satellite operators, space agencies, and policymakers) to do their work with greater confidence. In particular, satellite operators will be better able to assess when they can significantly reduce collision risks by using satellite thrusters to make small orbit changes. But, as their commentary shows, this can only be done if we promote research that leads to a better characterization of (and ultimately a reduction in) the uncertainty in forecasts of thermospheric density and satellite drag.

Citation: Berger, T. E., Holzinger, M. J., Sutton, E. K., & Thayer, J. P. [2020]. Flying through uncertainty. Space Weather, 18, e2019SW002373. https://doi.org/10.1029/2019SW002373

—Michael A. Hapgood, Editor, Space Weather

An Exoplanet with Evolving Clouds of Salts

Thu, 02/27/2020 - 12:28

Cloudy exoplanets are fairly common, with many worlds around other stars featuring continuous cloud banks and belts. Now, for the first time, researchers have spotted clouds actually forming and dissipating, changing on timescales of only a few hours. The salt-rich clouds of potassium chloride and sodium chloride on Kepler-434 b condense and rain down on their planet only to evaporate back into gases, rising up in the atmosphere to begin the cycle again.

Researchers have spotted similar cloud changes on other planets that orbit their stars in ellipses, and they suspect the process is widespread. With their relatively high eccentricities, these exoplanets may provide insights into how clouds wax and wane on other worlds.

“These eccentric planets are just these natural laboratories where you’re not changing the planet, you’re just slowly cranking up the heat and seeing what happens,” said Jason Dittmann, an exoplanet researcher at the Massachusetts Institute of Technology. “This is almost as close as a laboratory experiment as you can get.”

Dittmann presented the research at the winter meeting of the American Astronomical Society in Honolulu, Hawaii.

Clouds of Kepler-434 b

Dittmann scoured data from NASA’s planet-hunting Kepler mission to investigate Kepler-434 b, approximately 3 times the mass of Jupiter and the only known planet in its system. Dittmann noted that Kepler-434 b had an unusual light fingerprint, and follow-up observations from the ground revealed that the exoplanet’s path is slightly stretched into an ellipse, changing the amount of radiation it receives over its nearly 13-day orbit.

“It’s like the sun comes up and the fog goes away.”Kepler-434 b’s strange light signals shift in relation to its orbit. When the planet is close to the star, it glows brightly, then fades as it moves away. Dittmann determined that the changing brightness is caused by clouds forming and dissipating with the planet’s shifting temperatures.

When Kepler-434 b is far from its star, temperatures are cool, and gas in the atmosphere collects around solid particles to form fairly stable clouds. As the planet draws closer and temperatures increase, the clouds dissipate into gas in the atmosphere, allowing researchers to observe the bright temperatures of its glowing surface.

“It’s like the sun comes up and the fog goes away,” Dittmann said.

When Kepler-434 b is orbiting in close proximity to its star, its clouds grow too massive to maintain their integrity. At this point, they begin to rain. Because Kepler-434 b is a gas giant, the solid salts don’t fall to solid ground. Instead, they rain into the planet’s interior, where rising temperatures can cause them to evaporate. The rising gas returns to the atmosphere and begins the process again.

“Very Different Types of Clouds”

The new observations are intriguing, according to Laura Kreidberg, a researcher who studies exoplanet atmospheres at Harvard University. Kreidberg is not a part of the Kepler-434 b research. “Characterizing the atmosphere of planets beyond the solar system is difficult in the best of times,” she said. “Detecting the signal of a cloud at all is a major achievement. Detecting variability goes a step further beyond that.”

Dittmann plans to continue to scour the Kepler data in search of other planets with changing cloud cover. “We think this could be a general thing,” he said.

Observing multiple worlds with changing clouds can help researchers to draw better conclusions about the widespread process of cloud formation for distant planets.

“The physics and chemistry in these atmospheres are so complicated that it’s hard to make a statement about just one,” Kreidberg said.

In addition, Kreidberg hopes that theorists will begin to construct models that can explain in greater detail what is happening in the atmosphere of Kepler-434 b. “None of the solar system planets have changes in temperatures like what this planet is experiencing,” she said. “These are very different types of clouds from the Earth and other planets in the solar system.”

—Nola Taylor Redd (@NolaTRedd), Science Writer

Climbing the Occasionally Cataclysmic Cascades

Thu, 02/27/2020 - 12:25

From British Columbia in Canada to Northern California, an oddly straight line of snow-crowned stratovolcanoes towers thousands of meters above the landscape, visible from cities like Seattle, Wash., and Portland, Ore. In the past 200 years, several of these behemoths have erupted. Most spectacular was Mount St. Helens in 1980, in a blast that scattered ash across 11 states.

So how many of these volcanoes will erupt in the next few thousand years? According to geologists, all of them.

How to Climb a Stratovolcano

Some of the world’s most iconic and dangerous volcanoes are stratovolcanoes, including Mounts Fuji, Pinatubo, Vesuvius, and Kilimanjaro. Stratovolcanoes are identified by steep-sided cones formed by many layers of successive eruptions.

I suspect that many mountaineers earn their ice axes on stratovolcanoes.The first really big mountains I ever climbed were stratovolcanoes: 5,790-meter Cayambe and 5,897-meter Cotopaxi, both in Ecuador. I suspect that many mountaineers earn their ice axes on stratovolcanoes. The climbs tend to be relentless trudges up loose, steep slopes, although some routes require glacier travel skills using ropes, crampons, and ice axes. Vertical rock climbing on stratovolcanoes is rare; the rock is too loose and dangerous. .

My ski partner makes his way past the Devil’s Kitchen, an active fumarole in the crater of Mount Hood (3,429 meters). Mount Hood is home to 12 named glaciers and snowfields, and it is famous for summer skiing. The previous major eruption occurred in 1781, with a minor event in 1907. Credit: Mary Caperton Morton

. The Cascades have enough peaks to keep even the most prolific mountaineer busy for years. Dozens of volcanic features march north to south for over 1,100 kilometers, from the Silverthrone Caldera in southwestern British Columbia, to Lassen Peak in Northern California. The snow-capped stratovolcanoes—including Mounts Baker, Rainier, St. Helens, Hood, and Shasta—are the most visible features in the range, but dozens of calderas, cinder cones, lava domes, and shield volcanoes also occur along this volcanic arc. .

The Cascade Volcanic Arc parallels the offshore Cascadia Subduction Zone. Partial melting of oceanic slabs descending under the North American plate fuels the volcanoes, depicted here by black triangles. Credit: USGS

.

All these diverse volcanic features have one thing in common: They are driven by the Cascadia Subduction Zone just 95 kilometers off the Pacific coast. Here the Gorda, Explorer, and Juan de Fuca tectonic plates are diving under the North American plate at the rate that fingernails grow. As these oceanic plates descend under the continent, the escalating heat and pressure produce hot, buoyant magma that rises and collects in chambers underlying the inland volcanic features.

The existing Cascade volcanoes sit atop the eroded remains of older volcanoes, explained Tom Sisson, a geologist with the U.S. Geological Survey (USGS) in Menlo Park, Calif. “The current Cascade volcanoes are mostly younger than half a million years, and many of them sit atop older volcanoes,” Sisson said. “It’s somewhat arbitrary how we define where the old volcano ends and the younger one begins, but for whatever reason, they seem to form in the same location and have a life span on the order of half a million years.”

Eavesdropping on Sleeping Stratovolcanoes

The volcanoes are relatively active. “If you average things out, there are roughly two eruptions per century in the Cascades, often multiple-year-long eruptions,” Sisson said. Mount St. Helens has hogged the limelight in the past few decades with multiple eruptions in the 1980s and early 1990s, and from 2004 to 2008, but “it would not surprise me if another volcano raised its hand during our lifetimes,” he noted.

In 2018, USGS scientists designated eight volcanoes in Washington and Oregon as “very high threat” based on their eruptive history and proximity to populated areas: Glacier Peak, Mount Baker, Mount Rainier, Mount St. Helens, Mount Hood, Three Sisters, Newberry, and Crater Lake. .

The author stands on South Sister (3,158 meters), the tallest and youngest of the Three Sisters volcanoes in central Oregon. From the summit, Middle Sister, North Sister, and Mount Washington appear in a line to the north, with Mount Jefferson and Mount Hood also visible on clear days. Credit: Mary Caperton Morton

.

Eruptions in the Cascades have the potential to cause extensive damage and loss of life because of their explosive natures, their years-long eruptive cycles, and their proximities to populated areas. Lahars (mudslides caused by rapidly melting snow and ice) can bury everything downstream. Ash plumes ejected high into the stratosphere from even the most remote peaks can travel vast distances and snarl air traffic.

The 1980 eruption of Mount St. Helens devastated the north side of the volcano and blasted nearly 400 meters of elevation off the summit. Credit: USGS

No climbers were on Mount St. Helens during the 1980 eruption, but three rope teams of mountaineers witnessed the event from near the summit of Mount Adams, another stratovolcano 56 kilometers east of St. Helens. “First it was a little puff at the top of the mountain [St. Helens]. Then, within 2 or 3 seconds, it appeared that the north side of the mountain just blew out. The whole top of the mountain was engulfed in the column of smoke. It rose like an atomic explosion…with sort of a shock wave that went to the north. It reminded me of the pictures you see on late-night TV of the world blowing up,” climber Fred Grimm recounted to the American Alpine Club.

A few minutes after the initial eruption, the sky turned black and the rope teams on Mount Adams were pelted with searing ash and pebbles, forcing them to take cover. None of the climbers was seriously injured, but elsewhere in the world, mountaineers have been killed during volcanic eruptions by noxious hot gas, falling debris, and landslides; in 2014 the Ontake stratovolcano in Japan erupted with little to no warning, killing 56 people on the flanks of the mountain.

Only a few of the Cascade volcanoes are sufficiently instrumented due to a combination of logistical and regulatory barriers.Stratovolcanoes have a sneaky reputation for awakening after hundreds or even thousands of years of silence, but there is usually some warning. Seismic, GPS, and other instruments can often detect magma moving deep underground from days to hours before an eruption. However, only a few of the Cascade volcanoes are sufficiently instrumented due to a combination of logistical and regulatory barriers, said Seth Moran, the scientist-in-charge at the Cascades Volcano Observatory in Vancouver, Wash.

“Mount St. Helens is the gold standard for the Cascades, with 25 seismic stations, 20 GPS stations, and other kinds of equipment,” Moran said. “It’s one of the best monitored volcanoes in the world.”

At the other end of the spectrum is Glacier Peak in northern Washington, “which by some measures is the second most explosive volcano in the Cascades, and yet it has only one seismic station,” said Moran.

Glacier Peak is the most remote of the Cascade volcanoes, and therein lies the problem: The mountain lies entirely within land officially designated as wilderness. “That poses a very substantial permitting problem,” Moran said. The Wilderness Act states that no permanent structures can be erected in designated wilderness areas, but the National Volcano Early Warning and Monitoring System Act authorized by Congress in March 2019 may help overcome that barrier. Last fall the USGS won permission to add monitoring stations within the wilderness zone on Mount Hood, after a 5-year battle. But even with a green light from Congress, logistical issues still abound.

This solar-powered GPS station on Monitor Ridge is one of over 2 dozen monitoring stations installed on Mount St. Helens to detect the early warnings of an eruption. This station was placed by UNAVCO, but the data are freely shared with USGS and other researchers. Credit: Mary Caperton Morton

“We can’t just plop down equipment wherever we want it due to the challenging terrain and unforgiving climate,” Moran said. “All of the Cascade volcanoes are [at] fairly high elevation, and winter is rough on our equipment. It’s not uncommon for instruments to get buried under [10 meters] of snow.”

Installing and maintaining equipment in remote, high-altitude settings sounds like a job for mountaineers, especially in the winter. Some researchers have mountaineering skills, whereas others work with specialists in the National Park Service, such as the Mount Rainier Climbing Rangers, Moran says. Snow presents unique challenges, but because the rocky slopes of stratovolcanoes tend to be dangerously loose during the summer, experienced climbers often aim their expeditions in the winter or early spring, when they can negotiate smooth snow on crampons or skis.

The Cataclysmic Cascades: How Explosive Will the Future Be?

So far, I’ve stood on top of about half of the major high points of the Cascades, and I intend to keep climbing. This spring I’m aiming to ski Mount Shasta! After all, there’s no telling how long the Cascade volcanoes will be gracious hosts. “The eight volcanoes that are considered to be the highest threat have all erupted in the [past] 7,000 years, and we would expect them all to erupt again within that kind of time frame,” Moran said.

On longer timescales, however, the fate of the Cascades will be tied to the evolution of the diminishing Cascadia Subduction Zone, said Ray Wells, a structural geologist with the USGS in Portland. “You need subduction to produce the Cascade Range, and the subduction zone is getting progressively smaller over geologic time.”

As it converges at a rate of 50 millimeters per year, the subduction zone is being shortened by 100 kilometers every 2 million years. “We don’t really know how fast it will wink out,” Wells said. “But in 10 million years, I would expect that both the Cascadia Subduction Zone and the Cascade Range will be very different animals.”

—Mary Caperton Morton (@theblondecoyote), Science Writer

Living in Geologic Time is a series of personal accounts that highlight the past, present, and future of famous landmarks on geologic timescales.

Susan Hough Receives 2019 International Award

Thu, 02/27/2020 - 12:22
Citation Susan Hough

Few scientists have had a greater impact on promulgating earthquake awareness and education in developing nations than Susan Hough. She has tirelessly enriched cooperative projects between the United States and local scientists in Kashmir, Pakistan, Haiti, Nepal, and, most recently, Myanmar—nations reeling from the trauma of recent devastating earthquakes or from political upheavals and uncertainties. Through workshops and training sessions in these countries, her collaborative projects have empowered local scientists to engage in earthquake activities ranging from running their own seismic networks to assessing seismic hazard and reporting scientific results. As part of these programs she has also enriched the experience of foreign scientists by inviting them to participate in visits to scientific establishments and professional meetings here in the United States.

Sue has also authored five books about earthquake science for the general public, several of which have been translated into foreign languages. In her books, not only does Sue distill complex scientific information in a clear and intelligible form for the general public, but she layers it with history, context, and color—and her excitement for the scientific enterprise is contagious throughout.

Perhaps more than anything, her eagerness to promote capacity building has been undertaken with a selfless determination and a complete absence of ego. In many countries, she has found herself disarming local officials with gentle persuasion and demonstrating by example that women in science are first and foremost scientists, able to contribute with equal integrity to pushing forward the frontiers of knowledge.

As an AGU Fellow with over 150 publications to date, Susan Hough is the rare combination of a top-caliber scientist who has also contributed immensely to hazard preparedness and resilience in developing countries. We are pleased to present her with AGU’s International Award.

—Roger Bilham, University of Colorado Boulder

 

Response

I am honored and humbled to receive this award.  Thank you so much, Roger, Morgan, and the others who wrote letters of support and, of course, AGU.

I would also need to acknowledge colleagues who have been vital contributors to Team USGS over the years: Irving Flores, Jason De Cristofaro, Emily Wolin, Dan McNamara, and Nicholas van der Elst, as well as Roger Bilham, who has made some contributions himself in an international arena. And none of my international work would have been possible without the support for the U.S. Agency for International Development, Office of U.S. Foreign Disaster Assistance, which understands the critical importance of long-term risk mitigation, and the dedicated professionals at the U.S. Department of State.

But let’s talk about capacity development. Capacity development is only ever possible when there are existing capacities to be developed. One thing I have learned over the years is there are existing capacities in every country that faces earthquake hazard. It has been the privilege of a lifetime to work with and get to know students and professionals in the countries where I have worked: Myanmar, Nepal, Haiti, India, and Pakistan. I have been awed on a regular basis by the dedication, energy, and talents of partners who face enormous challenges on a daily basis. I’ve told the story of the day I landed in the mother of all traffic jams in Haiti—an adventure I will never forget—and the realization that hit me later, that my epic experience was just one more chaotic day in a lifetime of chaotic days for Haitians, who face daily life with a resilience and resourcefulness beyond what outsiders ever see. There is a hunger for training and resources in so many parts of the world where dedicated professionals and students understand the hazard and yearn to make their countries safer. As scientists we know that Earth science is a global science. But where capacity development is concerned, thinking globally requires acting locally, doing everything we can to strengthen existing local capacities. I accept this award on behalf of the professionals at institutions that continue to do the heavy lifting with risk reduction in their respective countries: the Myanmar Department of Meteorology and Hydrology, the Nepali Department of Mines and Geology and National Society for Earthquake Technology, the Haitian Bureau des Mines et de l’Energie and Université d’État d’Haïti, and others.

Thank you again.

—Susan Hough, University of Arizona, Tucson

Cleaner Air Takes Some of the Bite out of European Winters

Wed, 02/26/2020 - 12:57

New findings suggest that cleaner air can have an unexpected effect: fewer very cold days.

A recent study in Nature Climate Change found that restrictions on the emissions of aerosols, which include particles created when coal is burned, resulted in local warming because there were fewer aerosols in the atmosphere to reflect sunlight. The effect of aerosols on radiation in and around the atmosphere is known as radiative forcing, and the researchers say this is the first study to link anthropogenic aerosol forcing with extreme winter weather in Europe and northern Eurasia.

Straightening Out the Jet Stream

The scientists from the California Institute of Technology (Caltech) and NASA’s Jet Propulsion Laboratory (JPL) looked at atmospheric data from 1970 to 2005. They analyzed the movement of the Northern Hemisphere polar jet stream and its undulations, known as Rossby waves, and found there was a marked decline in extreme Rossby wave activity at high latitudes, mainly northern Eurasia. The reduction in Rossby wave activity corresponded to a reduction in aerosol emissions in northern Europe.

On a regional level, aerosols could have a greater effect on extreme winter weather than greenhouse gases.After performing climate simulations, researchers found that the trend of fewer extreme winter cold days also corresponded to the reduction in Rossby wave activity and could be reproduced only after accurately accounting for reduced anthropogenic aerosol forcing.

The findings indicate that on a regional level, aerosols could have a greater effect on extreme winter weather than greenhouse gases, in part because of their destabilizing impact on the jet stream. When the jet stream is relatively stable, it’s less likely to loop southward, bringing with it Arctic chills and a stronger winter bite.

“Our model simulation further illustrated the mechanism of how aerosols affect winter weather by altering jet stream location and waviness,” said Yuan Wang, a research scientist at Caltech and JPL in Pasadena, Calif., and the lead author of the study. “The insight we gained is that the warming due to aerosol reductions in Europe enhances the meridional temperature gradient on the jet’s poleward flank and results in a significant suppression in extreme events over northern Eurasia.”

Scientists are still trying to unravel aerosols’ complex effects on global warming. A 2015 study, for instance, found that aerosols have a strong effect on the reflectivity of Earth’s atmosphere and that they absorb more solar radiation than previously thought. Another study, in 2017, determined that the global average radiative effect of aerosols for 2006 had an overall cooling effect but that different mixtures of aerosols in various regions produced different effects.

Aerosols and Climate Mitigation

The results of the Caltech-JPL study are an example of how aerosols can affect atmosphere dynamics and act as drivers of extreme weather. They also highlight the importance of understanding atmospheric aerosols in predicting extreme weather events, which is crucial for climate mitigation and adaptation strategies, says Megan Willis, an environmental chemist and postdoctoral fellow at Lawrence Berkeley National Laboratory’s Chemical Sciences Division in Berkeley, Calif. Willis was not involved with the new study.

“As someone who studies the detailed chemistry and composition of atmospheric aerosols, this study really highlights for me the importance of understanding that chemistry and of identifying the most important aspects of that chemistry so it can be better included in global models like those used in this study,” Willis adds.

Wang says he and his colleagues plan to continue researching anthropogenic aerosol effects on other high-impact weather and climate extremes on both regional and global scales.

—Tim Hornyak (@robotopia), Science Writer

Sediments May Support the Mediterranean Megaflood Hypothesis

Wed, 02/26/2020 - 12:45

Six million years ago, the Mediterranean Sea was cut off from the Atlantic Ocean. The collision of the African and Eurasian tectonic plates caused the uplift of the Rif and Betic Mountains (in northern Morocco and southern Spain, respectively), closing at least two large straits or channels that connected the water bodies at the time.

This event caused a sudden increase in salinity in the Mediterranean, known as the Messinian Salinity Crisis (MSC), which in turn led to the formation of massive gypsum and salt deposits throughout the Mediterranean.

Scientists are still debating about what happened to sea levels in the Mediterranean after its western waterways closed. One possibility is that water evaporated quickly and sea levels fell by thousands of meters. Only a series of salty or brackish lakes might have survived. Eroded channels and sediment deposits in what might have been the ancient surface of the exposed Mediterranean basin seem to support this theory.

Zanclean Flood Hypothesis

The period of the dry Mediterranean might have ended quickly when the Strait of Gibraltar reopened 5.33 million years ago, causing a massive flood that refilled the empty basin in just 2 years. Seismic reflection imaging, a technique that relies on sound waves to image what lies underground, has revealed that beneath kilometer-deep Quaternary sediments, a huge erosion channel extends across the strait. The ancient channel, several hundred meters deep and 390 kilometers long, stretches from the Gulf of Cádiz (in the Atlantic) to the Algerian Basin (in the Mediterranean). Researchers think that this channel might have been carved during the flood as Atlantic waters rushed in to refill the Mediterranean.

[1/3] These two videos summarize our interpretation of what happened to the Mediterranean ~5 million years ago based on geological & geophysical data. First, the connections between the Atlantic and the Mediterranean may have closed due to tearing and sinking of the lithosphere pic.twitter.com/Jz0YZi29KI

— ∆(Garcia-Castellanos) (@danigeos) February 3, 2020

Looking for evidence to support this theory (called the Zanclean flood hypothesis), an international group of researchers recently identified buried sediments that could have been deposited by the flooding waters. “One of the recurrent questions was ‘Where did all the sediments accumulate after the flood?’” said Daniel Garcia-Castellanos, a geophysicist at the Institute of Earth Sciences Jaume Almera in Barcelona, Spain, who led the search and has studied the Zanclean flood hypothesis over the past decade.

Using computer simulations to recreate the opening of the strait and the subsequent flood, Garcia-Castellanos and his team identified low-flow areas that were likely to accumulate sediments. Then, they looked at seismic profiles of these areas to see if they could find the sediments.

A composite seismic profile shows the Messinian erosion surface (MSC, purple line) on the eastern side of the Strait of Gibraltar. This unconformity is interpreted as the erosion channel excavated into Miocene sediments during late Messinian Salinity Crisis or earliest Pliocene. Credit: Garcia-Castellanos et. al., CC BY 4.0

On the lee side of an ancient volcanic cone in the predicted path of the flooding, they found a large sediment deposit. It appears as an amorphous blob in the seismic profile, in contrast to the neatly stratified layers of marine sediments around it, suggesting rapid sedimentation. Its shape and size also seem to match the likely direction of the flood.

“This shape is compatible with the numerical models and with what we see in other megaflood settings,” Garcia-Castellanos said.

In 2018, the same group of researchers found similar deposits near a deep underwater gorge in the Malta Escarpment, the natural barrier separating the eastern and western Mediterranean basins. This gorge, known as the Noto Canyon, is the most likely location where the flood might have spilled over the escarpment to refill the eastern Mediterranean basin.

The main limitation of these simulations is the lack of knowledge about ancient seafloor topography. “We used the present-day seafloor morphology since we don’t know how it was in the past,” explained Garcia-Castellanos. “Nevertheless, these simulations give us a quantitative idea of how far can such a flow transport each grain size.”

The researchers published their findings in a paper reviewing the Zanclean flood hypothesis in Earth-Science Reviews.

To Flood or Not to Flood

The Zanclean flood hypothesis has its detractors. Many researchers studying the MSC are not even sure the Mediterranean actually desiccated much below its modern-day level.

One of the main problems with the desiccation theory is the utterly massive amounts of salt and gypsum thought to have been deposited during the MSC. If its waters had instantly evaporated, the present-day Mediterranean Sea would leave behind a layer of salt no thicker than 30 meters. In comparison, the salt layers associated with the MSC are up to a kilometer thick in some areas.

To accumulate so much salt, critics of the Zanclean hypothesis say, water had to be able to flow into the sea from the open ocean, albeit in a restricted way that could limit the escape of the denser, briny water. This dense water would sink to the deepest parts of the sea, where minerals could precipitate.

“This debate won’t end tomorrow.”Another controversial line of evidence is the networks of ancient channels thought to be the remains of ancient river systems. Current research suggests that these channels could have been carved by the flow of dense, salty water as it sank to the deepest areas of the sea. A similar effect could have formed the erosion channel at the bottom of the Strait of Gibraltar.

Looking for a different way to assess the problem, Javier Garcia Veigas, a researcher at the University of Barcelona not involved in the new research, looked at the isotopic signatures of Messinian gypsum deposits at several points in the Mediterranean. Biological activity and other factors can change the ratios of heavy to light isotopes of certain chemical species in seawater. These differences should be measurable in the minerals formed in aquatic environments with different isotopic compositions. However, Garcia Veigas didn’t find significant isotopic differences between rocks formed in the eastern and western Mediterranean basins, suggesting that they remained connected.

“I think that the consensus in the community is slowly drifting away from the megaflood hypothesis and increasingly moving towards a scenario where the Mediterranean did not fully desiccate,” Garcia Veigas said. “However, we won’t have definitive proof until a drilling campaign can reach the deep Mediterranean basin and confirm that what we see in the seismic profile is really salt formed during the Messinian.”

Garcia-Castellanos acknowledges that not everybody is on board with the Zanclean flood hypothesis. “All of the evidence that has been summarized in this article may have other possible interpretations,” he said. “So this debate won’t end tomorrow.”

—Javier Barbuzano (@javibarbuzano), Freelance Science Journalist

“Electron Wings” Can Interfere with Spacecraft Measurements

Wed, 02/26/2020 - 12:28

Spacecraft that take measurements of plasmas in the solar system—like the solar wind—or in Earth’s magnetic field are designed to avoid potential interference from the spacecraft itself. Because a spacecraft’s metal body is a conducting surface, currents of ions and electrons flowing through it can produce electric and magnetic disturbances as the spacecraft plows through space plasmas, like a boat producing a sheath of waves around it and a wake directly behind it.

Usually, spacecraft designers avoid these effects by placing instruments on the ends of meters-long booms that extend outside a spacecraft’s sheath and wake. But now Miyake et al. have identified another form of spacecraft interference that they have dubbed electron wings—features that are broader and not as easily avoided as previously known sources of interference.

The researchers’ computer simulations, run using the electromagnetic spacecraft environment simulator (EMSES) software, show that these wings are generated when a few conditions are met. First, the spacecraft must be negatively charged. Second, it must be traveling nearly perpendicular to the direction of the local magnetic field. Third, the spacecraft must be as large as or larger than the average electron gyroradius (the radius of electrons’ circular motion).

Under these conditions, a negatively charged satellite will repulse incoming electrons, pushing them off to its sides if the spacecraft is traveling fast enough through plasma. The electrons will be directed along magnetic field lines in jetlike flows that resemble wings in the researchers’ models, extending tens or even hundreds of meters to the sides of the spacecraft.

These expansive wings are hard to avoid even with booms: Spacecraft are often placed in slow spins to stabilize them, so booms would pass through the electron wings twice per rotation, creating data artifacts. Indeed, the team identified anomalies in electric field readings from the Freja spacecraft that correspond to their predictions.

The authors wrote that this previously unidentified effect may occur commonly at Earth’s magnetic poles, where the magnetic field lines are approximately vertical. The magnetic poles are an area of great interest for both orbiting satellites and suborbital sounding rockets, so researchers should take steps to identify and eliminate this interference in their data analysis, they noted. (Journal of Geophysical Research: Space Physics, https://doi.org/10.1029/2019JA027379, 2019)

—Mark Zastrow, Freelance Writer

Brian May Receives 2019 Athelstan Spilhaus Award

Wed, 02/26/2020 - 12:26
Citation Brian May

Dr. May’s contributions to public awareness and appreciation of the space sciences are literally unique on the planet. World famous as the lead guitarist for the rock band Queen, he also holds a Ph.D. in astrophysics, which he was awarded in 2007 by Imperial College London for his studies of the zodiacal light. Just by being a rock star who went back to complete his doctoral studies, he conveyed to the public in a way that no one else could that science is cool. Dr. May has used his celebrity as a science collaborator on NASA’s New Horizons mission to Pluto and the Kuiper Belt, the European Space Agency’s Rosetta comet mission, and the Japan Aerospace Exploration Agency’s Hayabusa2 asteroid mission.

Dr. May was an avid promoter of New Horizons during and after its 2015 Pluto encounter. He not only participated in numerous interviews and public appearances but harnessed the power of his Twitter account, which has almost 1 million followers. His work generating and publicizing stereo images from all these missions lets the public see the worlds we have explored with new eyes.

For New Horizons’ 2019 encounter with the Kuiper Belt object Ultima Thule, Dr. May raised his impact to a new and extraordinary level: He wrote and recorded a new song, “New Horizons,” to celebrate the mission. Coming as it did just a couple of months after the release of the enormously successful film about Queen, Bohemian Rhapsody, May’s involvement in the Ultima Thule encounter was an incredible boost to the mission’s visibility. Even readers of Guitar World’s website learned that Ultima Thule was giving us, in Dr. May’s words, “precious clues about how our solar system was born.”

The official video for “New Horizons” has been viewed 1.7 million times on YouTube, and countless more have heard the song on TV and webcasts. All have heard the world’s only astrophysicist/rock star singer.

Limitless wonders in a never-ending sky We may never, never reach them That’s why we have to try!

By using his rock star charisma to the show the world not just what we explore, but why, Brian May is truly worthy of the 2019 Athelstan Spilhaus Award.

—Andrew Chaikin, Arlington, Vt.; and John Spencer, Southwest Research Institute, Boulder, Colo.

 

Response

My love of astronomy began when, as a boy in the early 1950s, I begged to be allowed to stay up late to watch Sir Patrick Moore present BBC TV’s Sky at Night series. Around 1970, I began my Ph.D. studies at Imperial College London but left without completing my Ph.D., for a break to pursue my hobby of rock music—a break which turned into more than 30 years performing and touring the world with my band, Queen. It was Patrick Moore who encouraged me to resume work on my Ph.D. thesis, “A Survey of Radial Velocities in the Zodiacal Dust Cloud,” which I completed in in 2007.

This opened the doors for me to return to the world of astronomy and astrophysics. Soon afterward, I entered into my first collaboration in authorship, along with Sir Patrick and Dr. Chris Lintott: We wrote and published the popular science book Bang! The Complete History of the Universe.

In all my travels around the world, I have never been far away from astronomy, and recently, I have been able to contribute to several space missions through another lifelong passion, stereophotography.

In 2015 I was invited by principal investigator (PI) Alan Stern to join his NASA New Horizons team as a science team collaborator, and I worked on creating the very first stereo images of Pluto. Four years and a billion miles later, Alan invited me back to write a song to accompany New Horizons’ close encounter with the Kuiper Belt object Ultima Thule. My “New Horizons” single was released on New Year’s Day 2019 and premiered on NASA TV, to coincide with the flyby.

In 2015 I also worked with PI Matt Taylor on the European Space Agency’s Rosetta mission, creating stereo images of comet 67P/Churyumov-Gerasimenko. This year, in collaboration with the Japan Aerospace Exploration Agency’s Hayabusa2 team I created stereo images of asteroid Ryugu, the first C-type (carbonaceous) asteroid to be imaged at close quarters. Many of the stereos created from data sent back to Earth by these remote scientific space vehicles have been made with the help of my own collaborator, Claudia Manzoni, and I would like to acknowledge her and thank her for her expert and invaluable work.

I note that this award is for public appreciation and awareness of the space sciences; if, by sharing my experiences in words, 3-D images, and music with those who follow my activities, I have done something to help bring to the public the excitement of space exploration and the associated science, I am content. But receiving this award is a wonderful and unexpected bonus!

My grateful thanks to AGU.

—Brian May, Commander of the Most Excellent Order of the British Empire (CBE)

Novel Simulations of Upper Atmosphere Gravity Wave Dynamics

Tue, 02/25/2020 - 12:30

Small-scale gravity waves play a major role for the transports of energy and momentum from the lower to the upper atmosphere, and strongly impact upper level circulations. However, the details of gravity wave behavior and interactions across scales are complex and poorly understood.

Dong et al. [2020] make a new contribution to understanding gravity waves in the upper atmosphere from high-resolution numerical simulations. The simulations are the first to describe the propagation, breaking, and the resulting secondary generation of waves throughout the whole middle atmosphere and into the lower thermosphere (up to 260 kilometers altitude).

A rich phenomenology is revealed, raising fundamental questions about which phenomena matter for the coupling of different atmospheric layers. The results are leading to improved understanding of coupling of the lower and upper atmosphere.

Citation: Dong, W., Fritts, D. C., Lund, T. S., Wieland, S. A., & Zhang, S. [2020]. Self‐acceleration and instability of gravity wave packets: 2. Two‐dimensional packet propagation, instability dynamics, and transient flow responses. Journal of Geophysical Research: Atmospheres, 125, e2019JD030691. https://doi.org/10.1029/2019JD030691

—William J. Randel, Editor, JGR: Atmospheres

New Editor in Chief of Paleoceanography and Paleoclimatology

Tue, 02/25/2020 - 12:30

We are delighted to announce that Matthew Huber has just taken over as Editor in Chief of Paleoceanography and Paleoclimatology. We asked him some questions about his own research interests and his vision for the journal.

What are your own areas of scientific interest?

I love to think about the interplay between climate and life, so I study the dynamics of past climates and their paleobiological linkages, with an eye toward projecting into the future. Specifically, I study the ocean-atmosphere dynamics and radiative interactions that together govern the equator-to-pole temperature gradient, how these change as global average temperature rises, and the interactions between quantities and the biosphere.

During my student days, from being a geophysics undergraduate at the University of Chicago, to a Masters student at University of California, Los Angeles in atmospheric science, and then PhD student in Earth Sciences at University of California Santa Cruz, I learned to apply the tools of theoretical climate dynamics to understanding massive changes in temperature gradient revealed by data from Earth’s past, in order to develop more robust theories and models.

During those years I did not seriously think that the climate changes caused by humans would be of sufficient scale to rival the major disruptions in the paleoclimate record. Now I know better. The magnitude of change we are causing is truly ‘geological’ in magnitude, and the rapidity with which it is happening is nearly unprecedented. This means what was a purely theoretical or historical scientific endeavor—to me and many others in the field—has taken on a new sense of urgency and relevance. With this relevance comes some new responsibilities for the field: we must endeavor to generate more accurate information, with better characterized uncertainties, and to go beyond speculations to develop more rigorous and falsifiable theories.

What does it mean to you to serve as Editor in Chief of Paleoceanography and Paleoclimatology?

Being Editor in Chief of Paleoceanography and Paleoclimatology is a huge honor and responsibility. From its founding by the inimitable giant Jim Kennett all the way to the two most recent, amazing editors, Ellen Thomas and Stephen Barker, the journal has maintained high quality and impact while the field itself has broadened, deepened, and matured. I want to keep the unique ‘voice’ of the field that speaks through this journal and help make it louder and clearer. I want the voice of the past to roar so loud that the future cannot help but hear it.

How do you plan to take the journal forward in the coming years?

My first job is simple: Don’t screw it up! Honestly that will be my goal for the first year. Maintain the journal’s key strengths and high standards.

I’m very happy to announce that Ulla Rohl has agreed to be Editor of the journal as well, and I am so happy to have such an experienced and accomplished sea-going paleoceanographer sharing the helm.

Second, I want to enhance the diversity of voices heard throughout all steps of the journal process from submission, review, editing, publication and dissemination. That includes and is not limited to gender, country of origin, discipline, and subject matter. We are looking closely at metrics currently and refreshing the pool of Associate Editors and reviewers to better reflect the diversity of the field. My aim is to bring on a third Editor to help round-out the background and expertise at the editorial level as well. I hope in a year or so to be able to announce progress on making Paleoceanography and Paleoclimatology more inclusive.

The third major task I see—and it is shared across all AGU journals—is the fundamental alignment toward FAIR (Findable, Accessible, Interoperable, and Reusable) data practices. This is not just a procedural issue of submitting a spreadsheet when a paper is submitted, although it is that too. To be truly FAIR means rethinking what a journal is in a digital, online, machine-readable age.

We need to adopt practices more common in other fields including community curated repositories and community governed data standards, thorough and pervasive citation of underlying datasets, meta-analyses and syntheses, and containerized publication of all data and code necessary to reproduce an entire analysis. This will require a community-wide adjustment of practices, but given the long history of sample and data sharing as exemplified by the decades of success of scientific ocean drilling, I think this community is well-posed to emerge of leaders in FAIR practice within the geosciences. I am committed to placing Paleoceanography and Paleoclimatology at the forefront of AGU journals as an agent of change in the area of FAIR data, which I believe will ultimately result in more diverse, inclusive, sound and impactful science.

—Matthew Huber (huberm@purdue.edu; 0000-0002-2771-9977), Department of Earth, Atmospheric, and Planetary Sciences, Purdue University

Between Past and Future

Tue, 02/25/2020 - 12:29

Scientists reconstructing climates, environments, and ecosystems of the past can be seen as balancing between past and future: on one hand we use observations in the present world as a key to understand what happened in the past, but on the other hand—and increasingly so—we  use what we see in non-analog past worlds as a way to predict a potentially non-analog near future. Having recently ended my term as Editor in Chief of Paleoceanography and Paleoclimatology, I feel somewhere between past and future of the journal.

Expanded scope, change in name

I started my term in December 2015 as Editor in Chief of Paleoceanography, to end my term as EiC of Paleoceanography and Paleoclimatology in December 2019. The change in name occurred instantaneously on 01 January 2018. However, we can interpret this change (as I did in 2017) as a tipping point, i.e., a sudden change reflecting a much longer-term evolution, running invisibly below the surface.

In 2014, my predecessor Chris Charles announced that the scope of the journal had expanded to embrace all aspects of global paleoclimatology, as reflected in an informal name change Paleoceanography: An AGU Journal exploring Earth’s Paleoclimate. The AGU Focus Group (now Section) Paleoceanography and Paleoclimatology was deeply involved in the decision to formalize this name change, and its president Figen Mekik organized a survey in 2016: more than 65% of the 751 respondents voted in favor.

Over the life time of the journal Paleoceanography (1986-2017), our scientific undertaking vigorously evolved, from using mainly ocean-based data to our present investigations of global change involving linkages between open-ocean sediment proxy records and records from a broad range of environments and recorders: corals, ice cores, coastal marshes, speleothems and lakes, and building ever-expanding two-way connections between data and understanding through earth system and climate modeling. It is fully in line with this evolutionary process that my successor, Matt Huber, is a climate modeler, with no primary home-base on land or in the sea.

The data challenges

Important for our journal has been the adoption by AGU of the FAIR data standards (Findable, Accessible, Interoperable, and Reusable. In practice, this change involved the requirement that authors place data in an online repository, making them easier to find and access than data in supplements of varying formats.

It does not need saying that since its inception in 1986, Paleoceanography has been at the forefront of data-sharing: the field of research obviously requires comparing data across time and space. However, even after addressing the F and A in FAIR data, we have far to go to ensure the I and R, and we need community input to reach that goal.

As a simple but widely experienced example, far too many paleoceanographers have spent too much of their time trying to figure out, redo, and standardize numerical age models and accumulation rates. I am therefore thrilled that Paleoceanography and Paleoclimatology published a paper entitled PaCTS 1.0: A Crowdsourced Reporting Standard for Paleoclimate Data, by Deborah Khider and more than 90 co-authors which opens a dialog for working on the standards needed to ensure that our data are truly interoperable and reusable by our colleagues.

Hopes for the future of the journal

One of my hopes for the future of the journal is that it will remain a community resource for collaboration in ensuring that our hard-won proxy data are as well and extensively used as possible, and for keeping communication lines open within the community. A related hope for the future is that Paleoceanography and Paleoclimatology will remain and further develop as the journal where we as a community can look at an honest analysis of the precision and accuracy of our proxies, as well as potential boundary conditions for their use.

More and more stable isotope, organic biomarker and trace element proxies are being developed for more and more environmental parameters. With environmental parameters for which we now have multiple proxies, such as sea surface temperature, we have the opportunity to see more and more discrepancies (for example, Lawrence & Woodard, 2017; Zhang & Liu, 2018; Gray & Evans, 2019). Evaluation of differences between proxies is fundamentally important, since we need it to understand our proxies and their limitations.

I hope that Paleoceanography and Paleoclimatology will persist in offering quantitative and integrative analysis of coupled ocean-atmosphere-biosphere processes, as well as thoughtful explorations of limitations as well opportunities, being not just a place to publish papers, but a forum for our community to discuss how we practice our craft.

I am confident that I leave the journal in the best of hands, and that the new Editor in Chief Matt Huber and co-editor Ursula Röhl will keep the journal in excellent shape at a time of continual changes in the world of scientific publishing, with ongoing developments as to open access for the global community.

Thanks

I want to end by expressing my heartfelt thanks to all current and former members of our editorial team for their readiness to give their time, enthusiasm and professionalism: co-editors Heiko Pä­like and Steve Barker, as well as Associate Editors Helen Bostock, Gabe Bowen, Min-Te Chen, Oliver Friedrich, Nathalie Goodkin, Guy Harrington, Bärbel Hönisch, Sandy Kirtland-Turner, Matt Lachniet, Zhifei Liu, Chris Poulsen, Isabella Raffi, Chris Reinhard, Jim Russell, Joellen Russell, Dani Schmidt, Liz Sikes, Ryuji Tada, and Dave Thornally. Thank you all so much, all that work was much more yours than mine.

Finally, thanks to the staff in the AGU Publications Department: Robert Dawdy, Randy Townsend, Paige Wooden, and Sara Young. Despite my tendency to complain loudly and repeatedly to you all, I truly appreciate your assistance, without which I could not have functioned.

—Ellen Thomas (ellen.thomas@yale.edu;  0000-0002-7141-9904), Department of Geology & Geophysics, Yale University

Los Incendios del Amazonas Contribuyen al Derretimiento de los Glaciares Andinos

Tue, 02/25/2020 - 12:29

This is an authorized translation of an Eos article. Esta es una traducción al español autorizada de un artículo de Eos.

El verano pasado, los incendios que se extendieron por el Amazonas, recibieron atención a nivel mundial. En agosto de 2019, se triplicaron los incendios forestales activos en la Amazonía brasileña en comparación con  agosto de 2018, y hubo más que en cualquier agosto desde 2010. Este aumento se atribuye en gran medida al desbroce de tierras para la tala y la agricultura: En julio de 2019 hubo casi 4 veces más deforestación que el promedio de julio de 2016 a 2018.

A medida que la biomasa ardía, producía enormes columnas de humo que iban hacia la atmósfera. Científicos mostraron en una nueva investigación, que las partículas de carbono negro del humo pueden caer sobre los glaciares andinos hacia el oeste, haciendo que se derritan más rápido. Este material (hollín), producido cuando la biomasa y otros combustibles a base de carbono no se queman por completo, reduce la capacidad de reflexión del hielo y la nieve, y aumenta la cantidad de calor que absorben de la luz solar.

Se sabe que el carbono negro de los combustibles fósiles y la quema de biomasa en el hemisferio norte, ha acelerado el derretimiento de los glaciares en el Ártico, dijo Newton de Magalhães Neto, investigador de la Universidad Estatal de Río de Janeiro en Brasil y líder de este estudio. En América del Sur, explicó, “la cuenca del Amazonas es la mayor fuente de carbono negro, a través de la quema de biomasa,” y está cerca de los glaciares andinos tropicales.

La circulación de aire de este a oeste en la región tropical ecuatorial puede transportar aerosoles desde la quema de biomasa en el Amazonas hasta los glaciares tropicales andinos, principalmente en Bolivia y Perú.Para evaluar el impacto del carbono negro amazónico en los glaciares, los investigadores estudiaron el glaciar Zongo en Bolivia, centrándose en los años 2007 y 2010, cuando hubo más incendios de lo habitual en el Amazonas.

Después de identificar las principales fuentes de columnas de humo en la cuenca del Amazonas durante los incendios, el equipo modeló el movimiento de las partículas como el carbono negro a través de la atmósfera. El modelo mostró que una circulación de aire predominante de este a oeste en la región ecuatorial tropical puede transportar aerosoles desde la quema de biomasa en el Amazonas hasta los glaciares andinos tropicales, principalmente en Bolivia y Perú.

Al comparar el modelado atmosférico con los datos de núcleos de hielo, los investigadores estimaron las concentraciones de carbono negro en el glaciar Zongo. Al igual que las simulaciones de transporte de partículas, los núcleos de hielo mostraron un comportamiento que varía fuertemente con las estaciones, con niveles bajos de carbono negro en Zongo durante la estación húmeda y valores altos durante la temporada de incendios en el Amazonas.

Los investigadores calcularon que el carbono negro de los incendios de la Amazonía puede aumentar el derretimiento de los glaciares entre un 3% y 4%. Sus análisis también mostraron que el impacto del carbono negro depende de las concentraciones de polvo en el glaciar, porque el polvo absorbe calor que de otro modo sería absorbido por el carbono negro. Utilizando mediciones reportadas previamente, estimaron que los niveles bajos de polvo (~ 10 partes por millón) también aumentan el derretimiento glaciar en un 3% y 4%, mientras que las altas concentraciones de polvo (~100 partes por millón) aumentan el derretimiento glaciar en aproximadamente un 11%. Cuando están presentes tanto el carbono negro como el polvo, pueden aumentar la fusión de los glaciares entre un 6% y un 12%, dependiendo de si los niveles de polvo son bajos o altos.

“Descubrimos que para los glaciares andinos tropicales, la quema de biomasa en la cuenca del Amazonas […] contribuye significativamente al proceso de derretimiento,” dijo de Magalhães Neto.

En 2010, por ejemplo, los investigadores hallaron que el carbono negro de los incendios de Amazon aumentó la escorrentía anual de agua del glaciar Zongo en un 4.5%.

Impactos Sociales Para América del Sur

Los autores hicieron notar en el estudio que el efecto del carbono negro en el derretimiento de los glaciares puede parecer pequeño, pero es significativo y debería tenerse en cuenta en modelos futuros, particularmente durante años con un gran número de incendios en el Amazonas. Escribieron que las predicciones futuras del cambio climático apuntan a una Amazonia oriental más seca, lo que aumentaría el riesgo de incendios. Y dado que se espera que la demanda mundial de alimentos aumente la deforestación de esta zona, también se espera que aumente el uso de técnicas agrícolas de tala y quema, causantes de muchos incendios en la región.

Thorsten Seehaus, un glaciólogo de la Universidad Friedrich-Alexander Erlangen-Nürnberg en Alemania, dijo que los glaciares de los Andes están perdiendo masa de hielo. “En Perú, por ejemplo, desde el año 2000, se ha perdido alrededor del 30% de la superficie del glaciar,” dijo Seehaus (no participó en el estudio). Debido al impacto social del derretimiento de los glaciares andinos analizar las causas de la pérdida de los glaciares es crucial, mencionó. “Es importante ver cuáles son los cambios y mejorar las predicciones para el futuro, especialmente con respecto a la gestión de los recursos hídricos.”

En América del Sur, los glaciares son fuentes cruciales de agua para millones de personas, por lo que su pérdida acelerada es motivo de preocupación.En América del Sur, los glaciares son fuentes cruciales de agua para millones de personas, por lo que su pérdida acelerada es motivo de preocupación. En este contexto, los autores del estudio escribieron que sus resultados muestran que la quema de biomasa en el Amazonas aumenta la vulnerabilidad de los suministros de agua a escala continental. El trabajo fue publicado en Scientific Reports.

Esto es “un estudio muy necesario ya que hemos sospechado durante mucho tiempo que el carbono negro podría desempeñar un papel importante en el derretimiento de los glaciares andinos,” dijo Mathias Vuille, científico del clima de la Universidad de Albany en Nueva York (no participó en el investigación). “Hemos visto esto principalmente en el Himalaya y, en cierta medida, también en los glaciares del Ártico y en Groenlandia,” dijo Vuille, “pero no se ha realizado mucha investigación sobre si realmente hay un vínculo” entre los incendios del Amazonas y el derretimiento de los Andes.

Seehaus agregó que el trabajo proporciona un buen punto de partida para futuras investigaciones. Dijo que en el futuro, los datos satelitales podrían usarse para mapear los cambios estacionales en el albedo de los glaciares—una medida de la cantidad de luz que reflejan los glaciares—en diferentes áreas de Perú y Bolivia.

“Un siguiente paso importante para este trabajo es expandir el análisis a otros glaciares en los Andes tropicales,” dijo de Magalhães Neto. “Para esto, implementaremos un programa de monitoreo completo que tenga en cuenta [los] datos glaciológicos, hidrológicos, meteorológicos y de aerosoles atmosféricos.”

—Michael Allen (michael_h_allen@hotmail.com), escritor de ciencias

This translation was made possible by a partnership with Planeteando. Esta traducción fue posible gracias a una asociación con Planeteando. Traducción de Josué E. Esparza Escalante y Alejandra Ramírez de los Santos.

James E. Broda Receives 2019 Edward A. Flinn III Award

Tue, 02/25/2020 - 12:28
Citation James E. Broda

Dr. James Eugene Broda perfectly fits the criteria for the Edward A. Flinn III Award. He is truly one of those “unsung heroes who provide the ideas, motivation, and labors of love that build and maintain the infrastructure without which our science could not flourish.” For (an incredible) 49 years, Jim has served hundreds of oceanographers, particularly marine geologists and geophysicists, who have relied on his unique blend of knowledge, creativity, careful planning, sharp intellect, and critical thinking to plan and bring to successful fruition both ordinary and extraordinarily outrageous scientific projects. His work over these 5 decades has enabled our science and greatly improved us as scientists.

In his lifetime of achievement, it is not easy to pick out the highlights. Among the “ordinary” accomplishments is his participation in an (incredible) 125 (and counting) oceanographic research cruises, 52 with Woods Hole Oceanographic Institution (WHOI) chief scientists, for a total of nearly 10 years at sea! Of course, it is inaccurate to use the term “participation” to describe Jim’s role in these expeditions. He was and is, in most cases, vital to the success of the expeditions, from the earliest stage of planning, through the realization of the cruise, and afterward, through his indispensable role in curating in perpetuity the samples and data.

Many of Jim’s accomplishments have been more “extraordinary” than “ordinary.” One that stands out is his design of the WHOI “long corer,” originally installed on the R/V Knorr in 1997 (now also installed or planned for installation on Korean and German research vessels). That system allowed scientists to retrieve many large-diameter piston cores of 30- to 40-meter length with nearly perfect recovery and quality. It is surely the most innovative and technically advanced sediment corer ever built. In this case, Jim responded to a community need and used his great abilities and perseverance to accomplish something that no one else could have. Many important scientific publications have followed, none of which would have been impossible without Jim’s work.

While these technical endeavors are exemplary, they barely touch on the body of work achieved throughout Jim’s incredible career of accomplishment and self-sacrifice for the entire seagoing oceanographic community (time at sea exacts a cost both physically and emotionally). We are thrilled that this extraordinary man is finally being awarded the great honor that he so richly deserves.

—Paul A. Baker, Duke University, Durham, N.C.; and Lloyd D. Keigwin, Woods Hole Oceanographic Institution, Mass.

 

Response

It is indeed an honor to be recognized by this medal from AGU. I humbly express my deepest gratitude to all those who supported my nomination. Thanks also to the innumerable colleagues and shipmates with whom dedication to dreams and love of exploration was shared.

In the spirit of cooperation, part of the creed of this medal, these others should share much of the praise for the contributions accredited to me. They enabled concepts to grow with funding and technical challenges. My career spanned over some of the greatest breakthroughs in ocean engineering, and I was blessed to be surrounded by those engaged in changing the way we look at and understand the ocean.

Over the decades and an excursion of the planet, I sought to evolve safer and more capable seafloor sampling systems. They grew in size and complexity to meet the challenges of the marine geological community. Seismic refraction operations that involved high explosives became a focus, and hundreds of tons of charges were deployed in discreet experiments. As ocean bottom receivers came to pass, so did our completely unique ability to deploy and detonate explosives on the sea floor at full ocean depth.

I was fortunate to have the support and inspiration to apply emerging technologies to solve marine geological equipment development issues. I had the rare opportunity throughout my career to learn by doing and take conceptual CAD drawings onto the shop floor, see them turn into finite objects, then head out to deep water to test and refine the creation.

Finally, sincere thanks to Dr. Paul Baker, Dr. Bill Curry, Dr. Rick Murray, and Dr. Mike Purdy for their generous citation, continued support, and shared adventures over the years. It is very gratifying to have shared so much with so many, from bosuns to postdocs and a visionary or two.

—James E. Broda, Woods Hole Oceanographic Institution, Mass.

Searching for Mount Meager’s Geothermal Heart

Tue, 02/25/2020 - 12:27

As Canada attempts to transition from a hydrocarbon-based economy to a renewable clean energy economy, the country seeks new options. Canada has abundant hydropower potential as well as wind and solar potential, but each of those energy sources comes with challenges, from controversies over new large dam construction to issues with intermittent generation. So Canada is also examining geothermal energy, a resource with many benefits compared with other renewables, to meet its goal of achieving net zero emissions by 2050.

High exploration risk is one of many barriers that has limited investments by industry in geothermal projects. But this is a risk that geoscience research can reduce.Geothermal power plants have small footprints (unlike hydropower plants), low emissions, and direct-heat-use opportunities, but most important, they provide stable baseload power, unlike intermittent wind and solar sources. Offsetting the many positive aspects of geothermal energy is the higher exploration risk; it is much easier for planners to establish where it is sunny and windy than where there are exploitable heat sources deep underground.

Geothermal energy also requires pumping hot fluids from depth to the surface. The high fluid production rates needed to run a power plant (at least 100 kilograms per second) necessitate discovery of deep high-permeability aquifers that continuously deliver sufficient fluid to a well. Finding these permeable rocks in the subsurface is a key geothermal exploration risk that is tied to the expense of drilling. High exploration risk is one of many barriers that has limited investments by industry in geothermal projects. But this is a risk that geoscience research can reduce, which is where our wide-ranging team of geoscience experts—and our recent adventure into the Canadian Cordillera—comes in.

Geothermal Potential Near Mount Meager

To encourage geothermal energy exploration, the Geological Survey of Canada, with support from Geoscience BC, a nonprofit geoscience research organization, and the Natural Resources Canada Emerging Renewable Power Program, initiated a new project in 2019 focused on reducing exploration risk. A highlight of this project is a recent multidisciplinary field program aimed at developing novel tools to predict the occurrence of highly permeable zones within the Mount Meager volcanic complex, Canada’s only currently active volcano.

After being dropped off, researchers carried heavy equipment plus survival gear, often hiking along mountain goat trails, to reach sites inaccessible by aircraft. Credit: Stephen E. Grasby

Lying 160 kilometers north of Vancouver, B. C., Mount Meager is in the northern part of the Garibaldi Volcanic Belt, representing the northern segment of the Cascadia Subduction Zone. Volcanism over the past 2.6 million years along this volcanic arc is a result of the continuing subduction of several microplates (the Juan de Fuca, Explorer, and Gorda plates) beneath North America. The most recent volcanic activity at Mount Meager was an explosive eruption about 2,400 years ago; however, fumaroles and numerous thermal springs at the volcano suggest a currently active geothermal system.

The world faces a new energy (and climate) crisis, and geothermal once again looks like an appealing option.During the energy crises of the 1970s, research and exploration at Mount Meager revealed world-class geothermal resources with fluid temperatures exceeding 250°C at about 2-kilometer depth. However, the fluid production rates were insufficient to justify the expense of building power lines to the site, so plans to develop geothermal power there were abandoned.

Now the world faces a new energy (and climate) crisis, and geothermal once again looks like an appealing option. But the challenges haven’t gone away. Renewing exploration at Mount Meager, as well as within other volcanic belts in western Canada, requires new ideas and methods for the prediction of high-permeability zones at depth.

The geoscience team assembled by the Geological Survey of Canada to tackle this challenge comprised 34 researchers from a total of seven universities and government agencies. We brought together people with expertise in geological and structural mapping, volcanology, geophysics (especially gravity, magnetotelluric, and passive seismic surveying), geochemistry, regional stress field analyses, and hydrogeology into one coherent research project and sent everyone into the field from July to October 2019. The goal of the fieldwork was to use an integrated geophysical, geochemical, and geological approach to see into the heart of the mountain and enable clearer identification of high-permeability zones within the known thermal anomaly.

Into the Mountains

The Mount Meager area provides a number of challenges, so our fieldwork started with a lot of planning. First, we met with representatives of the Squamish and Lil’wat First Nations, as the field locations we intended to visit lay within their traditional lands. Our conversations resulted in a very positive collaborative approach to coplanning the field surveys. Through this coplanning, we eliminated unintended intrusions onto Spirited Grounds or ancestral burial areas by relocating some proposed survey sites to alternative locations that still supported the project’s scientific mission. We also moved some planned survey sites from pristine areas to previously disturbed grounds to limit our overall impact on the landscape. In the field, we were accompanied by a wildlife monitor from Lil’wat First Nation, who provided valuable support to minimize the risk of team members encountering bears (and all of whom she seemed to know by name).

Scientists installed dozens of instruments, including gravimeters, at sites amid the Mount Meager volcanic complex to collect data that should help determine locations with the most geothermal energy potential. Credit: Stephen E. Grasby

Finding appropriate survey sites and wildlife encounters were just a couple of the challenges of this fieldwork. The group also contended with rough terrain, high elevations, and snow and ice. The Mount Meager massif includes some of the most rugged terrain of the Canadian Cordillera, and access has been limited since a 53-million-cubic-meter landslide in 2010 (Canada’s largest historic event) destroyed bridges on old logging roads. So the research teams had to be deployed via helicopters.

Every day, helicopters dropped teams of two to four people, carrying heavy backpacks and equipment, onto ridges, peaks, and otherwise inaccessible valley bottoms. Field survey teams hiked along high mountain ridges, on old overgrown logging roads, or through thick bush. For some geophysical surveys, groups of four or more people were required to carry the heavy, bulky survey equipment in addition to personal survival gear. And at times, clever solutions—such as helicopter slinging and using precarious mountain goat trails—were needed to move delicate equipment across narrow ridges and down steep slopes. Accessing fumaroles was a particular challenge, as they are located in subglacial ice caves filled with deadly hydrogen sulfide gas, so we had to take oxygen-supplying rebreather masks with us.

Over the course of the summer (375 person-days in the field), the research teams installed a temporary (2-month) network of 59 three-component seismic sensors along with a distributed acoustic sensor cable; they also conducted magnetotelluric (MT) measurements at 107 sites and gravity measurements at 79 sites, and made geological and structural observations at 903 sites. We analyzed the geochemistry of four thermal springs, which, although they required long hikes to reach, did provide the side benefit of easing sore muscles. We tried to sample the fumaroles in the ice caves but ran into trouble because of late-season ice melt that slowed our progress and because we could cover only short distances with the limited air supply provided by the rebreathers.

A member of a field team lays a sensor cable along a ridge to help collect magnetotelluric (MT) measurements. All told, the campaign recorded MT data at 107 sites, as well as gravity and geological data at many others. Credit: Stephen E. Grasby Imaging Mount Meager Anew

Over the coming year, we will use the data collected during the field campaign and from the installed sensors to examine surface and subsurface features of the volcanic complex. We will use data from the seismic and MT arrays to image magma chambers as well as the distribution of fractures and high-permeability zones that carry geothermal fluids through the subsurface, linking deep magma chambers with thermal springs and fumaroles at the surface. Spatial gravity measurements in conjunction with other geophysical methods will allow comprehensive mapping of subsurface magmatic and hydrothermal features.

Geological mapping and field observations, meanwhile, will help define the nature and spatial distribution of volcanic and basement rock types and structures making up the Mount Meager volcanic complex. One focus will be on locating geological domains that potentially display high-permeability reservoir properties—those rocks that hold hot water and through which water easily flows. As solid volcanic rock often has low porosity—and thus low capacity to hold water—we have so far examined areas where the rock is naturally highly fractured, measuring the density and orientation of the fractures to predict likely directions of water movement.

The data are currently being processed (into projects by three postdoctoral fellows, six doctoral candidates, one master’s candidate, and one undergraduate at universities in Canada) and will be integrated into a new 3-D model of the geothermal and volcanic plumbing system of the Mount Meager complex. This model should greatly reduce the risk associated with drilling for geothermal reservoirs in volcanic systems of British Columbia and help support Canada’s transition to a clean energy economy.

Acknowledgments

This research project could not have occurred without the contributions of all the researchers and students involved, including the following: from the Geological Survey of Canada, R. Bryant, Z. Chen, J. A. Craven, J. Liu, S. M. Ansari, and V. Tschirhart; from Simon Fraser University, A. Calahorrano-Di Patre, M. Muhammad, and G. Williams-Jones; from the University of Calgary, J. Dettmer, H. Gilbert, R. O. Salvage, and G. Savard; from the University of Alberta, C. Hanneson and M. J. Unsworth; from the University of British Columbia, M. Harris and K. Russell; and from Douglas College, N. Vigouroux-Caillibot. The research team greatly appreciates support from pilots Marco Accurso, Denis Vincent, and Ralph Sliger of No Limits Helicopters; planning and field support by Maxine Bruce and Tammie Jenkins of Lil’wat First Nation; and ongoing field support by Wayne Russell of Innergex Renewable Energy Inc. In addition, the field program was substantially supported by Innergex Renewable Energy, which provided lodging and logistical resources at its nearby run-of-river facility. Christian Stenner provided the unique skills required to enter volcanic glacial ice caves.

Author Information

Stephen E. Grasby (steve.grasby@canada.ca), Geological Survey of Canada, Calgary, Alta.; and Carlos Salas, Geoscience BC, Vancouver, B. C.

The Threat at Thwaites

Mon, 02/24/2020 - 14:25

Thwaites Glacier Diagnosing Thwaites   What Lies Beneath Is Important for Ice Sheets   Controlled Explosions Pave the Way for Thwaites Glacier Research   “Glacial Earthquakes” Spotted for the First Time on Thwaites   The Threat at Thwaites

The best—or at least most entertaining—thing I learned from this issue is that glaciers tend to behave “like pancake batter on a frying pan.” Ted Scambos offers that description in this month’s cover story, “Diagnosing Thwaites.”

Scambos is the lead scientific coordinator for the U.S. side of the International Thwaites Glacier Collaboration (ITGC). Launched in 2018, this large research initiative hosts eight teams studying the past, present, and future of Thwaites, one of Antarctica’s most unstable glaciers. The problem with Thwaites, and with the West Antarctic region generally, is that it’s pancake batter sliding around in too much oil—as it loses mass from both above and below, ocean water is creeping in underneath and reducing the friction between the ice and the bedrock, allowing it to slide freely over the water. The more it flows, the faster it may calve ice, and scientists have serious worries that this will create a runaway situation called marine ice sheet instability.

It will not surprise you to learn that a catastrophic collapse at Thwaites could have alarming effects on sea level rise worldwide. That’s why the ITGC teams are spending four austral summers drilling into the ice, collecting bedrock samples, and building model after model to help the experts get a grip on what is happening there.

There are challenges that come with studying unstable ice at the bottom of the world, and sometimes you must address them by blowing up things in Texas.Of course, there are challenges that come with studying unstable ice at the bottom of the world, and sometimes you must address them by blowing up things in Texas. In “Controlled Explosions Pave the Way for Thwaites Glacier Research,” read about one of the ITGC teams trying to study the bedrock underneath the ice. The researchers can “basically create X-ray images of the landscape” by detonating explosives near the surface of the glacier and mapping how the seismic waves propagate, says the lead scientist on the team. If you’d like to learn more about how bedrock affects glaciers generally, head to “What Lies Beneath Is Important for Ice Sheets” to meet some researchers gaining insight into glaciology and ice vulnerability by reconstructing the topography under Antarctica back 34 million years.

Elsewhere in the issue, we hope you’ll turn to “Understanding Our Environment Requires an Indigenous Worldview” to learn about ice—this time in Alaska—from a different perspective. Raychelle Daniel, of Yup’ik descent, describes the consequences of conducting science and creating science policy without the unique contributions of the indigenous people immersed in the environment. Daniel’s article was the excellent conclusion of a weeklong series of articles on diversity perspectives published at Eos.org. Find the entire series here.

See you all next month.

—Heather Goss (@heathermg), Editor in Chief

Tracking the Grand Canyon’s Mysterious Springs

Mon, 02/24/2020 - 12:43

More than 5 million people visit Arizona’s Grand Canyon National Park each year, and every drop of water they drink out of the park’s faucets comes from a single source on the North Rim called Roaring Springs.

Mapping the springs’ own sources is not straightforward: From the surface, rain and snowmelt flow through 1,100 meters of rock, caves, faults, and sinkholes before emerging at the springs. Now a new groundwater vulnerability model is taking more of the Grand Canyon’s geological complexity into consideration, giving scientists the best tools yet for protecting the park’s drinking water supply.

When Jones set out to do a vulnerability analysis for the springs, she found that the underlying geology was far too complex for existing models.Roaring Springs is reached by a 7.5-kilometer walk down the North Kaibab Trail. Here an impressive waterfall shoots from between rock layers, forming the headwaters of Bright Angel Creek. A portion of the springwater is captured in a pipe that runs under the trail for 15 kilometers down to the Colorado River, across the river, and up to the South Rim.

“Protecting this water source is critically important to the Park Service,” said Natalie Jones, a hydrologist at Northern Arizona University in Flagstaff and lead author of the new study, published in Hydrogeology Journal. Initially, Jones set out to map sinkholes on the Kaibab Plateau, which forms the North Rim of the Grand Canyon.

“In the past, people had visually identified a couple hundred sinkholes, but using lidar scanning I mapped almost 7,000,” Jones said. The high density of sinkholes makes the plateau especially vulnerable to contamination from surface pollution, but when Jones set out to do a vulnerability analysis for the springs, she found that the underlying geology was far too complex for existing models. “So we set out to modernize the model by incorporating more of the high-resolution topographic data that [are] available for the Grand Canyon,” she said.

The World’s Grandest Layer Cake

The new model more accurately captures the Grand Canyon’s world-famous geologic layer cake structure, said Ben Tobin, a karst hydrogeologist with the Kentucky Geological Survey at the University of Kentucky who was also an author on the new study. “Most models are designed for just a single unit of rocks. In the Grand Canyon, we have a wide variety of rock types layered [2,000 meters] thick.”

The Grand Canyon’s hydrology is dominated by two stacked aquifers, one in the Kaibab limestone layer at the top of the cake and another in the deeper Redwall and Muav limestone layers. In between the two aquifers are hundreds of meters of rock layers that are not as permeable to water, such as the Coconino sandstone and Hermit shale. A network of sinkholes, faults, and fractures cuts through these less permeable layers, connecting the two aquifers.

Thousands of sinkholes riddle the North Rim of the Grand Canyon, where the dissolution of water-soluble limestone and gypsum has produced a karst landscape. These photos are of the same 10-meter-deep sinkhole, taken a week apart. Credit: National Park Service

“The modifications that we made to the models are an effort to pinpoint where those connections are likely to be between the upper aquifer and the lower aquifer,” Tobin said.

The outputs from the new model more accurately reflect the high degree of connectivity between the aquifers, Jones said. For example, a 2017 study found that after a storm event on the rim, changes in the temperature and flow rate of springs emerging 580 meters below the rim occurred within 6 days. “That’s pretty fast considering the water is traveling through almost [600 meters] of rock from the rim to the spring,” she said. In other places in the Grand Canyon, it may take months or even years for snowmelt on the rim (the most common form of precipitation in the Grand Canyon) to emerge at springs in the inner canyon, depending on those underground connections.

Testing the Waters

Tobin said the new models are a “starting point” for further testing of vulnerabilities to Roaring Springs. “The faster infiltration of water means that contaminants can move through the system quickly as well.”

The models will also be used to shed light on the sustainability of the springs in response to climate change.The models will also be used to shed light on the sustainability of the springs in response to climate change, which is projected to bring decreased snow and rain to the U.S. Southwest.

The next steps will involve more dye tracing studies, in which nontoxic fluorescent dyes are used to trace the flow paths of water from the rim to the springs. The new models will help the research team strategize where to drop dye on the rim, perhaps reducing their hiking by a few kilometers.

“Dye tracing studies in the Grand Canyon are the most challenging fieldwork I’ve ever done,” Tobin said. “For one study, in 30 days in the field, we hiked 280 kilometers up and down 21,000 meters of elevation.”

The new models should also be useful in other geological settings, said Laura Crossey, a geochemist at the University of New Mexico in Albuquerque who was not involved in the new study. “The Grand Canyon is the ultimate laboratory for figuring out new fundamentals of karst science,” she said. “It’s a unique setting, but what we learn there about flow and connectivity can certainly be applied in other places.”

—Mary Caperton Morton (@theblondecoyote), Science Writer

Santa Ana Winds and Wildfires Influence Air Pollution

Mon, 02/24/2020 - 12:23

Fine particulate matter (PM2.5) in the air, defined as bits of debris and aerosols with diameters less than 2.5 micrometers, has negative impacts on human health, including contributing to cardiovascular and respiratory illnesses. This material is emitted into the skies from a variety of sources, such as combustion in automobile engines, coal-fired power plants, and wildfires. Once in the atmosphere, how PM2.5 particles circulate depends greatly on local winds.

In Southern California, for example, where wildfires occur most often at the end of the dry season, Santa Ana winds can shift where fine particulate matter winds up. These northeasterly winds occur between September and May and result from dry air that warms over southwest facing coastal topography before flowing down from the mountains and offshore. In fall, when conditions are driest, the Santa Ana winds can be a major exacerbator of wildfires.

In a new study, Aguilera et al. compare local data on PM2.5 concentrations against records of Santa Ana winds in Southern California. Their combined data set spans from 1999 to 2012 and reveals that the influence of the Santa Ana winds on PM2.5 concentrations depends on if and where fires are burning.

In the absence of upwind wildfires, strong Santa Anas reduced PM2.5 air pollution over Southern California by sweeping PM2.5 out to sea. However, when wildfires are burning, the winds had the opposite effect, stoking the fires inland and transporting ash and other particulate debris from them to coastal cities.

In general, the Santa Ana winds decreased PM2.5 particulates most in inland ZIP codes during years with fewer fires, whereas the biggest increases in PM2.5 were observed in coastal ZIP codes in years with widespread wildfires.

Projections of the dynamics of Santa Ana winds as well as of the changing precipitation regime in Southern California (i.e., with the wet season starting later) suggest that there could be more chances for consecutive Santa Ana wind days fanning wildfires and burning larger areas, which in turn would increase human exposure to fine particulates from wildfire smoke. (GeoHealth, https://doi.org/10.1029/2019GH000225, 2020)

—David Shultz, Science Writier

Basu, Ismail-Zadeh, Leinen, Millar, and Wu Receive 2019 Ambassador Awards

Mon, 02/24/2020 - 12:23
Citation for Sunanda Basu Sunanda Basu

Dr. Sunanda Basu has strived tirelessly to promote the talent pool and diversity of early-career scientists across the globe, advocated nationally and internationally for space weather science, and reinvigorated international collaborations in emerging nations.

In service to the community, Sunanda cochaired the Scientific Organizing Committee for the International Heliophysical Year−Space Weather Science and Education Workshop (Ethiopia) under the auspices of the United Nations Basic Space Science Initiative. The workshop was followed by a meeting in Zambia, culminating in the prestigious international AGU Chapman Conference in Ethiopia, the first of its kind in space science in Africa. She served on the Scientific Committee on Solar-Terrestrial Physics’s Long-Range Planning Committee and executive committees for the International Union of Radio Science (URSI), chaired the Climate and Weather of the Sun-Earth System (CAWSES) Steering Committee, and was an active leader of the National Science Foundation’s Coupling, Energetics, and Dynamics of Atmospheric Regions (CEDAR) program. At AGU she was chair of the Development Board and served on the Board of Directors and award committees.

Sunanda’s philanthropic contributions are of particular note. She and her late husband endowed the Basu International Early Career Award for scientists in developing countries, recognizing outstanding contributions to research in Sun-Earth systems science. This AGU Space Physics and Aeronomy section prize has recognized talented scientists from China, India, Peru, South Africa, and Nigeria. She later endowed the U.S. version of this award, followed by an URSI early-career endowment and two awards for early-career scientists living and working in Africa. The African Geophysical Society bestowed a fellowship in recognition of her substantial contribution to Earth and space sciences in Africa.

Her service and philanthropy took place in parallel with her excelling as an outstanding international scientist, representing the core of AGU’s mission. The impact of her scientific leadership is recognized by her general lectures at international associations, such as “Impacts of Extreme Solar Events” at the URSI General Assembly, the International Association of Geomagnetism and Aeronomy Association Lecture on CAWSES science in Toulouse, and the CEDAR Distinguished Scientist Lecture. Her research into the ionosphere, its structure, and its irregularities has huge societal relevance associated with impacts on communications and satellite navigation. Sunanda contributed to the inception and very foundation of the U.S. National Space Weather Program Strategic Plan, now recognized at the highest levels in the Office of Science and Technology Policy.

Sunanda is an ambassador in every sense and a worthy recipient of AGU’s Ambassador Award through her service and scientific leadership, her tireless and unwavering promotion of international scientific talent, and her advancing awareness of societal impacts of space weather.

—Tim Fuller-Rowell, University of Colorado Boulder

 

Response

It is a humbling experience to receive the AGU Ambassador Award, and for this I am very grateful to AGU. My nominator, Tim Fuller-Rowell, and my colleagues Louis Lanzerotti, Roderick Heelis, and Archana Bhattacharya all took time from their busy schedules to write letters of support. For this I owe them a big debt of gratitude.

I have now spent about 4 decades in the United States coming from my native India. At first, my interest was to be immersed in science and use my insights to help others. Gradually, my passion evolved into helping the international community of scientists and, particularly, the next generation in whatever capacity I can. Growing up in a developing country and moving to the United States as a National Research Council postdoctoral scientist, I was able to realize how lucky I was to get this opportunity and how important it is to share my good fortune with others. My mother, if she were alive, would be, like AGU, 100 years old this year, and she instilled in me an obligation to try to meet the educational needs of young people with lesser opportunities.

My science and my life were a partnership with my late husband and colleague, Santimay Basu. In addition, both of us had been educated in India. Thus, with our global mindset and passion to help the next generation, we were able to endow through AGU annual early-career awards for scientists from developing countries within the space physics and aeronomy community, starting in 2008. Santi and I had spent our entire careers involved in space weather research and studying the societal relevance of the associated impacts on satellite-based communication and navigation systems. By definition this research was global in scope and lent itself well to involving young scientists from developing nations. Tim Fuller- Rowell has provided a lively commentary of our forays into other parts of the world. Suffice it to say that being able to enhance the size and diversity of AGU’s talent pool has been an award unto itself. Being recognized with the Ambassador Award is the icing on the cake!

—Sunanda Basu, National Science Foundation, Alexandria, Va., retired

Citation for Alik Ismail-Zadeh Alik Ismail-Zadeh

Dr. Ismail-Zadeh has the requisite research record, citations, and visiting professorships and fellowships that we expect of high-performing members of our fields. He is that and much more.

His scientific work is truly interdisciplinary, involving applied mathematics, geophysics, natural hazards, science diplomacy, and history across regions from the central Apennines to the Tibetan Himalayas. His engagement and leadership across the national and international geophysical scientific community are immense: He has helped promote geosciences from Earth observations and applications in the atmospheric, climate, and hydrological sciences to volcanology and space weather for the United Nations (UN) Educational, Scientific and Cultural Organization, the World Meteorological Organization, the Group on Earth Observations, and others. More broadly, he has supported disaster risk assessment and management efforts for the UN Office for Outer Space Affairs and the UN Office for Disaster Risk Reduction, including for controlling underground nuclear explosions through the Comprehensive Nuclear-Test-Ban Treaty Organization. In addition, he has initiated a number of outreach and education efforts, including the International Union of Geodesy and Geophysics (IUGG) Science Grants, Science Education, Science Publication, and Science Policy programs.

Dr. Ismail-Zadeh’s impact is long lasting. In one illustration, when he started the work on the formation of AGU’s Natural Hazards focus group in 2009, only a few professed interest. Today, the Natural Hazards section unites thousands of researchers. To wit, both IUGG and AGU have selected issues of natural hazards and disasters as key foci of their centennial scientific themes and celebrations.

Two telling statements from other highly recognized researchers in our fields reflect on Dr. Ismail-Zadeh’s singular characteristics: “What has been achieved in these areas has been due in no small measure, to Alik’s inputs and unique qualities. His efforts are tireless and is characterized by a willingness to use his own time in order to save yours.…above all, I value his mature judgment and guidance.” And “the sense of pride about his upbringing and family truly shows the human values he cherishes. Judging from his passion and commitment to our profession, this also reflects his feelings and unqualified commitment towards his scientific family, which has made him an ideal ambassador for Earth and Space sciences.”

There are many more such sentiments. Dr. Ismail-Zadeh’s contributions have been “seismic” on many levels. His formal recognition as an ambassador is a credit to the vision of AGU and most significantly attests to the power of employing science to help secure the safety and sustainability of our societies and systems.

—Roger S. Pulwarty, National Oceanic and Atmospheric Administration, Boulder, Colo.

 

Response

I am honored to receive an AGU Ambassador Award and am grateful to Roger Pulwarty for nominating me and to Harsh Gupta, Yuan Tseh Lee, Özlem Adiyaman Lopes, and Soroosh Soroshian for supporting the nomination. I am honored twice to receive the award in 2019, the year of the AGU Centennial and my 25-year membership in the Union.

Graduating as a mathematician, I moved to geophysics and dedicated my life to studies of dynamics of the lithosphere and mantle and their manifestation in sedimentary basin evolution and, later, in earthquakes and volcanic activities. It was the time of eureka, when scientific discoveries brought satisfaction, enjoyment, and happiness. The beginning of the 21st century, however, changed my professional life from pure science to science for society. After the 2004 great Indian Ocean earthquake and tsunamis, I asked myself, “What is the value of the science I am doing, if this science cannot protect people against disasters? What is a missing link between science and society?” My scientific adviser and colleague V. Keilis-Borok liked to say that “a scientist is not merely a person who conducts scientific research; a scientist is a person who cannot live without doing so.” So true…I would only add that a scientist is a person who should help society to improve well-being.

“An instant understanding, the efficiency of thought and action, and a good feeling that comes when the like-minded people work together…” (F. Press, as quoted by V. I. Keilis-Borok in One Hundred Reasons to be a Scientist, p. 124, Abdus Salam International Centre for Theoretical Physics, Trieste, Italy, 2004). For the past 2 decades, I have tried to work together with natural and social scientists and engineers in solving challenging problems of society, including disaster risk reduction, and to speak to representatives of industry and international nongovernmental and intergovernmental organizations as well as to national and regional policy makers to convince them that science is available and ready to be used in their daily activities to benefit humanity. What brings me the biggest satisfaction after scientific discoveries are the results of my voluntary work in various capacities on behalf of AGU, the European Geosciences Union, IUGG, and the International Science Council. Creating new knowledge and delivering it to society, being an ambactus of the scientific community, and bridging nations via science are my credo. I am pleased that AGU recognizes the contribution to service to the Earth and Space science community and science policy leadership with the award and happy to join AGU Ambassadors.

—Alik Ismail-Zadeh, Karlsruhe Institute of Technology, Germany; also at Russian Academy of Sciences, Moscow

 

Citation for Margaret Leinen  Margaret Leinen

Dr. Margaret Leinen’s insightful and bold leadership, enduring scientific contributions, national and international impacts, and focus on quality and equity are virtually unique in our modern society of researchers, educators, and policy designers. She has played many roles in important institutions, bringing a powerful integrative mind-set to her myriad positions in professional organizations while remaining a champion of high-quality, societally relevant inquiry into how best to approach our future as a global society. She has conducted excellent research, has administered programs empowering cutting-edge scientific inquiries, and has been intimately involved in designing national and international portfolios that provide financial support for basic and applied research. Leinen is a trendsetter on multiple issues at the interface of science and society.

Leinen’s influence has significantly enhanced organizations in academia, government, the private sector, and world policy-making bodies. Throughout all her work, she brings her considerable intellect and gracious generosity to ensure that all parties are enfranchised and engaged. Her work at the University of Rhode Island, the National Science Foundation, Climos, the Harbor Branch Oceanographic Institute, other institutions such as the State Department, and now as the director of the Scripps Institution of Oceanography and vice chancellor at the University of California, San Diego, is replete with examples of her tenacious and unrelenting positive approach to provide cutting-edge solutions over the years. As but one specific example, her multiyear terms as part of AGU leadership as president (and associated offices) resulted in new policies that drew long-overdue attention to misbehaviors associated with harassment and bullying. Under Leinen’s leadership, such actions were classified as “scientific misconduct,” thereby linking—for the first time in the geosciences—professional and personal (mis)conduct.

A common thread of Leinen’s accomplishments is her laudable ability to be involved in somewhat tense situations, capture the essence of the debate, and then offer tractable solutions. She is a prime example of what it means to be a true ambassador, whether addressing issues related to selection of sites for global change research in the early Joint Global Ocean Flux Study or the participation of underrepresented racial and ethnic groups in ocean sciences. She offers many examples as a role model for women scientists, and indeed for all scientists, in promoting efforts to increase participation of women and minorities in the geosciences.

Our world of geosciences is a better place because of Margaret Leinen.

—Richard W. Murray, Woods Holes Oceanographic Institution, Scituate, Mass.; and John R. Delaney, University of Washington, Seattle

 

Response

What a privilege to be among the 2019 Ambassador Awardees! I have been a member of AGU for over 40 years (time flies when you are having fun). During that time I have watched AGU grow from an organization that was primarily about publishing important journals for our fields—and organizing an annual meeting—to an organization that is committed to enhancing every aspect of members’ educational, research, and professional experiences. And just in time. The cultural and organizational structure of our science in the past is no longer appropriate for a diverse, international, interdisciplinary community of scientists that must respond to urgent calls for solutions to vexingly complex problems as well as generate basic scientific discovery at the frontiers. The human impact on the planet—whether a result of how many of us there are or a result of what we transform and add to the air, sea, and land or a result of what we remove—is straining the basic habitability of Earth and results in demands for new knowledge and new approaches.

These demands are calling all of us to rethink the way we educate Earth and space scientists and communicate with the public. We are also being asked to break barriers of participation so that innovative ideas from everyone and everywhere can be incorporated into our thinking. We are being asked to engage those outside of our fields to bring creative ideas and connections from other disciplines. Our universities are rushing to try to keep up with this transformation. Our companies place a premium on being nimble and creative. Our governments are trying to develop less bureaucratic approaches.

With AGU’s students, educators, researchers, business, and government, as well as our large international membership, AGU represents many human resources to generate geoscience knowledge. But AGU is also being challenged to serve this diverse membership during a time of incredible global and cultural change. Being an ambassador for our fields has never been more important. We who know and understand Earth and space science need to ensure that we reach out to all possible participants and partners to bring them into this commitment to a sustainable future. We also need to ensure that all can participate in an equitable way.  I know that there are many AGU ambassadors out there and hope that this award can begin to show them the importance of their work.

—Margaret Leinen, Scripps Institution of Oceanography, La Jolla, Calif.

 

Citation for Connie Millar Connie Millar

Dr. Connie Millar, who is fluent in genetics, paleoecology, forest ecology, climatology, glacial geology, landscape ecology, and wildlife biology, consistently integrates these disciplines to reveal insights about the dynamic biogeography of mountain ecosystems. As a scientific ambassador, she has built a community in mountain science and has catalyzed climate change adaptation on federal lands.

Connie’s 2007 paper “Climate Change and Forests of the Future: Managing in the Face of Uncertainty” was recognized by the Ecological Society of America (ESA) in 2015 as “one of the most notable papers ever published” in an ESA journal (i.e., since 1920). In Science in 2015, in “Temperate Forest Health in an Era of Emerging Megadisturbance,” Connie and coauthor Nate Stephenson outline how her research has turned traditional forest management on its head. Combining deep understanding of paleontology and genetics with observations of recent forest diebacks, they explain that there is no “ideal natural forest” to restore, and instead, managers must employ a tool kit combining “resistance,” “resilience,” and “realignment,” including identifying regions of climate refugia and facilitating species change and adaptation. Connie pioneered the needed multidisciplinary research in these ecosystems for global change, including founding and fostering collaborations through interdisciplinary groups such as the Consortium for Integrated Climate Research in Western Mountains and the Global Observation Research Initiative in Alpine environments, to provide the foundation for needed guidance for forest managers.

Connie’s work on climate adaptation, particularly with reference to fire and planning, has resulted in shifts in the U.S. Forest Service identity. Agency leaders regularly quote Connie’s work and rely on her to weave together various disciplinary ideas in a way that land managers can use. For this work, she received the Forest Service Chief’s Excellence in Science and Technology Award in 2013 for “developing and delivering scientific principles, partnerships, and actions for adaptation to climate change in national forests” and the 2016 Distinguished Science Award for “leadership and exceptional scientific productivity.”

Connie is an outstanding mentor. She works tirelessly to promote early-career, female, and minority voices in the Mountain Views newsletter she edits, as well in the many AGU sessions and MTNCLIM meetings she organizes.

Connie once remarked, “Interdisciplinary mountain research is for people who like steep learning curves.” Just as John Muir worked across disciplinary boundaries to establish protected mountain areas for future generations, so has Connie worked tirelessly to establish both the key science and the future talent pool to guide how we should manage and protect those areas through times of unprecedented change.

—Jessica Lundquist, University of Washington, Seattle

 

Response

I send deepest thanks to my citationist, Jessica Lundquist, and the colleagues who supported my nomination. Their selflessness and willingness to prepare the nomination package humble me and bear witness to a genuine concern for our community of scientists. The honor of this award compels me to seek greater responsibilities in applying interdisciplinary science in novel ways to the challenges of land stewardship. Especially in mountain regions, complexities of terrain, climate, biodiversity, land use, and diverse stakeholder interests combine to create problems of a wicked nature. These require nimbleness, access to diverse and high-quality knowledge, and assertive action with uncertain outcomes. Where there is urgency for solutions, temptations may arise for scientists to overstep study results, adopt inappropriately alarmist attitudes, and communicate information beyond available data. Now more than ever we need to embrace strict objectivity in interpreting our research results and translating them faithfully into defensible approaches for land management. Where communities of practice emerge, such as our western North American mountain climate consortium, scientists and resource managers working together enforce reciprocal transfer of best available and transparent science in the context of environmental and management challenges. Involving students and young scientists in on-the-ground projects with resource staff provides valuable mutual benefits and serves to maintain realistic understanding and lessen risks in decision-making. For addressing problems of changing climate and related pressures on mountain landscapes, I am greatly encouraged and inspired by the courage, knowledge, and dedication of the rising generations of scientists who are committed to harnessing new knowledge for the protection and resilience of mountain ecosystems.

—Connie Millar, University of Washington, Seattle

 

Citation for Lixin Wu Lixin Wu

Lixin Wu is widely recognized as a prominent leader in the field of multiscale ocean dynamics and climate change research. He pioneered the use of partial coupling systems (or model surgery) to unravel causative mechanisms operating in the complex oceanic and atmospheric feedback and subtropical-tropical linkage. He has made major original contributions to understanding the response of interannual, decadal, and interdecadal variability to greenhouse warming. He developed the first successful observation-based estimation of ocean mixing using high-resolution Argo floats in the Southern Ocean. He has discovered global warming “hot spots” along western boundary currents over the 20th century. His contribution has transformed the way we study these important issues.

While his scientific achievements are truly outstanding, his contribution to ocean sciences in enabling international collaboration is what makes him richly deserving of this Ambassador Award. The modern research landscape, science complexity, and limitation in resources present a plethora of challenges for scientists in any single country to tackle them alone, whether it is in the United States, China, or Australia. He initiated the Global Ocean Summit in 2014 to provide a regular platform for institutional leaders to enhance institutional coordination of global ocean observations. He launched a multidisciplinary research program known as “Transparent Global Oceans” in 2013 to build comprehensive observation systems for understanding ocean climate processes. “A Transparent Ocean” is now a goal of the United Nations Decade of Ocean Sciences. He established a workshop series, the International Symposium on Western Boundary Currents, that has been promoting interdisciplinary study of boundary current systems, particularly in a changing climate. He played a key role in the Northwestern Pacific Ocean Circulation and Climate Experiment, designed to observe, simulate, and understand the dynamics of the northwestern Pacific Ocean circulation and its climatic impact. More recently, Dr. Wu initiated the Centre for Southern Hemisphere Oceans Research, combining the research capability of the Commonwealth Scientific and Industrial Research Organisation, Qingdao National Laboratory for Marine Science and Technology, and Australian universities to study Southern Ocean climate variability and change, and the International Laboratory for High-Resolution Earth System Prediction, integrating the world-class capability of QNLM, Texas A&M University, and the National Center for Atmospheric Research, to better predict and project extreme weather in the present-day and future climate.

In summary, Dr. Wu’s sustained scientific accomplishments and influential leadership truly embody the code of a successful AGU ambassador. His contribution has had, and will continue to have, a substantial impact. He is an ideal and worthy recipient of AGU’s Ambassador Award.

—Weijian Zhou, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an

 

Response

I am honored to receive the Ambassador Award on the 100th anniversary of the founding of AGU, and I am grateful to the Union for this recognition.

I started my career in physical oceanography after education in computational fluid dynamics. I have been fascinated by cross-scale interactions in the ocean and climate system, its complexity, and the pressing need to observe, understand, and predict its change in a concerted way. That fascination continues to be my motivation.

My first cruise was to the western Pacific in the summer of 2008 after a decade-long period of working on modeling and theoretical studies of ocean circulation and climate. The severe seasickness, over much of the cruise, provided a moment to think about integration of observations, theories, and predictions so that our ocean is more transparent. Soon after the cruise, we established observational networks in the western Pacific and started to build a “Transparent Ocean Community.” Now after a decade of progress, the community has become internationally famous, and the mission of Transparentizing Global Oceans echoes resonantly with the sustainable goal of the United Nations Decade of Ocean Science.

A Chinese proverb goes, “The ocean is vast because it admits all rivers.” To facilitate the implementation of Transparent Ocean, we have held a series of biennial Global Ocean Summits since 2014, in which leaders of major marine institutions and organizations meet and discuss global partnership for ocean observations. In part as an outcome of these summits, we have established two international centers, the Centre for Southern Hemisphere Oceans Research and the International Laboratory for High-Resolution Earth System Prediction, which create opportunities and a platform for Southern Ocean research and high-resolution Earth system modeling and prediction, respectively. These collaboration hubs help galvanize concerted efforts and encourage broader participation in the endeavor to build a community of shared future for mankind. As an AGU Ambassador Award honoree, I look forward to working with colleagues and partners to accomplish this great cause.

My sincere gratitude goes to Weijian Zhou, my nominator, and supporting colleagues, as well as my family, friends, and students. With your support, I feel a lot more can still be achieved.

—Lixin Wu, Ocean University of China, Qingdao; also at Qingdao National Laboratory for Marine Science and Technology, Qingdao, China

Submarine Canyons Breed Megawaves in Japan

Fri, 02/21/2020 - 15:08

Locals in Toyama Bay, Japan, have a name for strange winter waves that arrive out of nowhere: YoriMawari-nami. The waves can reach nearly 10 meters (32 feet) and batter the shoreline for as long as a day, bringing wave after wave of crushing power. Some have even grounded cargo ships and snapped concrete barriers like twigs.

Scientists don’t know how the waves form, and local forecasting models can’t predict them.In February 2008, a wall of YoriMawari-nami pummeled towns along the bay, destroying 200 houses, flooding streets, killing two people, and injuring 18. The waves have been documented for centuries, but scientists don’t know how the waves form, and local forecasting models can’t predict them.

Hitoshi Tamura, a senior researcher at Japan’s Port and Airport Research Institute, set out to create a model that could better represent the waves. In the process, he uncovered a new characteristic of YoriMawari-nami that could be key to forecasting them successfully and even found links to a classic experiment by a 19th century physicist.

The Making of a Wave

Waves coming into Toyama Bay are very “clean,” said Tamura, because they all come from one direction. When winter storms whip up ocean swells traveling toward the bay in all directions, the shape of the bay’s peninsula allows only ocean swells from the north-northeast to travel ashore. The waves coming ashore are abnormally regular and unidirectional, said Tamura. “The wave shape is very beautiful.”

The clean waves can reap destruction, however, when they travel over submarine canyons lining the bay’s coastline. The submarine canyons look much like valleys below water, with cascading walls and gullies that stretch from the continental shelf down to the deeper ocean.

YoriMawari-nami (YM) waves act much like light in Thomas Young’s double-slit experiment. Credit: Tamura et al., 2020, https://doi.org/10.1029/2019JC015301, CC BY 4.0

Tamura showed that the submarine canyons focus the clean swells “like a lens.” As surface waves speed toward the shoreline, they interact with the ocean bottom. Incoming waves refract, or bend, over the canyon, and in some places, the waves meet in focal zones. At some meeting points, the waves positively combine, summing to a much larger wave height than their individual contributions. In other areas, the waves cancel each other out and have a lower wave height.

The effect is similar to a 19th century experiment conducted by physicist Thomas Young called the double-slit experiment. In Young’s experiment, sunlight passes through a small slit in a screen, letting through a smidge of light in the same frequency. The light then encounters another screen—this one with two slits—that redirects the light in different directions. On the final screen, you see how the light coming through the two slits interacts positively and negatively, creating light and dark patterns. The interaction is called coherent interference, and it is the key to YoriMawari-nami waves, said Tamura.

Swells on the Horizon

Coherent interference occurs elsewhere in the ocean, like just offshore Half Moon Bay, Calif., a popular spot among surfers. Perhaps the most famous example is in Nazaré, Portugal, where surfers can ride some of the most massive waves in the world, including the Guinness World Records’ largest wave ever surfed, 24.38 meters (80 feet) tall. The waves in Nazaré form from a submarine canyon that focuses and bends waves into behemoths.

Tamura said that despite their ubiquity, conventional forecasting models average out a particular attribute of waves, called phase, that is critical to calculating coherent interference. Tamura’s models include an extra term in the model’s equation to account for phase relationships, and Tamura hopes to combine models to create more powerful local forecasts.

Failing to account for interference can complicate navigation and lead to “gross underestimations of wave height prediction.”Researcher Pieter Bart Smit has studied coherent interference from submarine canyons off the coast of La Jolla, Calif., and said that Tamura and his collaborators “convincingly demonstrate that the observations can be explained if wave focusing is properly accounted for.” Smit, the head of ocean research at Sofar Ocean Technologies who was not involved in the research, said that failing to account for interference can complicate navigation and lead to “gross underestimations of wave height prediction.”

Tamura hopes to collect data to test his hypothesis by placing buoys over the submarine canyons in Toyama Bay and watching how the waves propagate in the real world. If he does this, he won’t have to wait long for data: Historical records show that about two YoriMawari-nami wave events occur each year.

“The hope is that I can generate a prediction system to predict YoriMawari-nami waves, so it can contribute to the coastal area and local people,” Tamura said. “That should be the final goal.”

Tamura presented his work at the Ocean Sciences Meeting 2020 in San Diego, Calif., and published the research in the Journal of Geophysical Research: Oceans last month.

—Jenessa Duncombe (@jrdscience), News Writing and Production Fellow

Representing Estuaries and Braided Rivers as Channel Networks

Fri, 02/21/2020 - 12:30

Because of human action on rivers, water streams have mostly been perceived as single-thread systems that carry water and sediment. Natural rivers are more complex because they exhibit not a single, well-identified channel but a network of entangled channels. Understanding their dynamics is of paramount importance to many scientific and engineering problems, for example in river restoration.

Hiatt et al. [2020] tackle this problem and propose innovative tools for studying channel networks in braided rivers and estuaries. Pattern identification is easy to the human eye but training a computer to do so is far more difficult. The authors show how the channel network can be determined from topographic and bathymetric data.

Citation: Hiatt, M., Sonke, W., Addink, E. A., van Dijk, W. M., van Kreveld, M., Ophelders, T., et al. [2020]. Geometry and topology of estuary and braided river channel networks automatically extracted from topographic data. Journal of Geophysical Research: Earth Surface, 125, e2019JF005206. https://doi.org/10.1029/2019JF005206

—Christophe Ancey, Associate Editor, JGR: Earth Surface

Theme by Danetsoft and Danang Probo Sayekti inspired by Maksimer