EOS

Ousted Head of Science Agency Criticizes Brazil’s Denial of Deforestation Data.

Data show that deforestation in the Amazon River basin has increased. Credit: iStock.com/luoman

The world’s lungs are starting to gasp for breath, and it’s not something we can sweep under the rug. This is excellent reporting by our own Randy Showstack on the attacks on the world’s largest rain forest and the scientists trying to protect it. —Kimberly Cartier, Staff Writer

 

Mapping the Strain on Our Water. Informative, well-illustrated article reporting on new data about water stress from the World Resources Institute (WRI). The article led me to WRI’s Aqueduct tools for a deeper dive into the data. —Faith Ishii, Production Manager

 

August Puzzler.

Credit: NASA Earth Observatory

Any other Pantone fans out there? This bird’s-eye view of vibrant green farmland brings me joy—from memories of flying over the Midwest as well as the beauty of geometric shapes in our everyday life. —Melissa Tribur, Production Specialist

 

2068: The Speculative Journalism Issue and To Fix the Climate, Tell Better Stories. Two outlets are making statements on the power of storytelling to make us truly understand the changes happening all around us. The journalists at High Country News took the findings from the Fourth National Climate Assessment and moved the clock ahead 50 years to speculate on how they might be reporting on a world that had stayed on this path. Nautilus magazine, meanwhile, insists that a one-sided “narrative vacuum” is the reason science hasn’t decisively won the climate change debate. —Heather Goss, Editor in Chief

 

With Artemis, NASA at Risk of Repeating Apollo Mistakes, Scientist Warns.

Artemis 1 will be the first integrated flight test of NASA’s deep-space exploration system: the Orion spacecraft, Space Launch System (SLS) rocket, and ground systems at Kennedy Space Center in Cape Canaveral, Fla. Credit: NASA

This is a solid reality check for those excited about the United States returning to the Moon with the Artemis program. Not only are there serious concerns about funding, but also “NASA stands a very real risk of turning the Artemis Program into a repeat of the Apollo Program—a flags-and-footprints sprint back to the Moon with no follow-through.” —Timothy Oleson, Science Editor

 

The Case for Climate Rage. A personal essay by Amy Westervelt on our emotions and climate change. When it comes to a climate crisis, who gets to be angry? —Jenessa Duncombe, Staff Writer

 

In Super-Deep Diamonds, Glimmers of Earth’s Distant Past.

Diamonds like this one excavated from Juína, Brazil, are providing geologists with clues about Earth’s interior. Credit: Graham Pearson, CC BY SA 4.0

Diamonds are so much more than a girl’s best friend, and it seems that for scientists, the more “flawed” one is, the more valuable it might be. Researchers have identified trace isotopes of helium in the inclusions of superdeep diamonds from Brazil, which suggests the presence of a reservoir of helium in Earth’s mantle. —Faith Ishii, Production Manager

 

The Planets, with Pluto and Ceres.

NEW! By popular demand…– The Planets with Pluto & Ceres –Shown: rotation, tilt, sidereal day. Tilts are "Obliquity to orbit" as there are multiple definitions of "axial tilt". There are many unmapped dwarf planets – astronomy never sleeps: https://t.co/e8usoWyN4v. #SciComm pic.twitter.com/C9oMfFEFwX

— Dr James O'Donoghue (@physicsJ) August 19, 2019

Simply mesmerizing to watch, and no, Mercury and Venus are not buffering. This animation is a great way to visualize the variety of ways planets (and not-quite-planets) spin in our solar system. Last year, this grid would have been incomplete: We only recently learned the length of Saturn’s day! —Kimberly Cartier, Staff Writer

 

This Thread on the World’s Best Academic Paper Titles.

STOP THE INTERNET! I just found the world's best paper title. pic.twitter.com/MZVPurtwAb

— Lisa Stinson (@lisafstinson) July 9, 2019

Scroll through the whole list. You’re welcome. —Caryl-Sue, Managing Editor

Slow-moving landslides creep just a few centimeters or meters per year, but they persistently alter landscapes via erosion.

Scientists have now analyzed hundreds of slow-moving landslides in Northern California to trace how their activity is linked to rainfall. The team found a pronounced uptick in the number of landslides in 2017, California’s second-wettest year on record. The slow-moving landslides active in 2017 also tended to be smaller, shallower, and faster than their brethren in drier conditions, the researchers showed.

Finding so many active landslides has implications for both hazard analyses and studies of how sediments are transported, the scientists concluded.

So Slow They’re Missed

“Sometimes people don’t even know they’re there and build on top of them.”The plodding pace of slow-moving landslides means they’re often missed.

“Sometimes people don’t even know they’re there and build on top of them,” said Alexander Handwerger, a geoscientist at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif., and the lead author of the new study.

But slow-moving landslides are important because they afford researchers a long-term look at how landslides, even the classical ones that rush down hillsides in a matter of seconds, unfold. “They’re essentially governed by the same physics as fast landslides,” said Handwerger.

Handwerger and his team studied slow-moving landslides in the Eel River catchment in Northern California. This catchment’s clay-rich, mechanically weak soil—paired with the area’s seasonal precipitation (mostly between October and May) and active plate tectonics—makes this region a hotbed for landslides, said Handwerger.

A Jet for Science

The researchers collected radar observations of roughly 4,700 square kilometers of the grassland-dominated landscape using NASA JPL’s Uninhabited Aerial Vehicle Synthetic Aperture Radar mounted on a modified Grumman Gulfstream III business jet. By comparing radio observations collected eight times between April 2016 and February 2018 using a technique called synthetic aperture radar interferometry, Handwerger and his team pinpointed areas where the ground had moved over timescales ranging from roughly a month to nearly 2 years.

The scientists focused on a time period that included a range of precipitation levels: 2016 was the final year of a historic drought, 2017 had above-average rainfall, and 2018 was again a drier year. “It was a really interesting time to study landslides because it went from extremely dry to extremely wet in a very short time period,” said Handwerger.

Smaller, Shallower, Faster

The researchers measured a significant jump in the number of slow-moving landslides in 2017. They found 312 landslides in water year 2017 (the time period between 1 October 2016 and 30 September 2017), more than double the number of slow-moving landslides in water years 2016 and 2018. Landslides active in 2017 tended to be smaller, shallower, and faster than their counterparts active in drier conditions.

“That so many landslides were active in that short period was surprising,” said Handwerger.

Furthermore, the scientists showed that the landslides active in 2017 tended to be smaller, shallower, and faster than their counterparts active in drier conditions.

“The extreme rainfall of 2017 triggered a widespread but short-lived increase in the activity and velocity of the landslides,” the researchers reported in June in the Journal of Geophysical Research: Earth Surface. That makes sense, Handwerger said, because smaller landslides, which tend to be shallower, are more sensitive to individual rain storms. Rainfall boosts the water pressure within soil, increasing its density and making it more likely to shear down a slope.

Slow-moving landslides will likely remain a fixture of the Northern California landscape, said Handwerger. That’s because annual precipitation and transitions between dry and wet conditions are both predicted to increase in California.

These slides will alter the environment by changing the shapes of hills and rerouting drainage networks, the researchers concluded. “That could have big implications for the sediment flux and hazard potential,” said Handwerger.

This “interesting and novel” study presents a largely complete and unbiased sample of rainfall-triggered landslides, said George Hilley, a tectonic geomorphologist at Stanford University in California not involved in the research. Despite the known link between rainfall and landslide activity, said Hilley, “seeing how many and how extensive these features are is enlightening.”

Handwerger and his team are looking forward to collecting more observations of slow-moving landslides, particularly in years with abnormal levels of precipitation. The researchers recently secured three more years of funding to use  NASA JPL’s Uninhabited Aerial Vehicle Synthetic Aperture Radar.

“We want to keep extending the time series,” said Handwerger.

—Katherine Kornei (@katherinekornei), Freelance Science Journalist

As water moves from high in the sky to deep in the ground, it picks up chemical signatures that can tell researchers secrets about Earth—from the density of air pollution to global ice cover to what kind of rock the raindrops seeped through. Scientists can look at specific radioactive isotopes and reconstruct past climates and weather patterns recorded in stored groundwater.

In a new paper in the Proceedings of the National Academy of Sciences of the United States of America, researchers leveraged an isotope of krypton (Kr) that can reach more than a million years back in time to discover the age of groundwater in the Negev desert in Israel.

Pairing krypton with other isotopes in groundwater, the researchers found two distinct ages and sources within the Nubian Sandstone Aquifer. They note that their method can be used to reconstruct paleoclimates from aquifers around the globe.

Arid Aquifers

Groundwater is an important resource for life on the planet, especially in arid regions. Replenishing, or recharging, groundwater requires that rainfall soak into the soil, traveling downward for storage in aquifers—a process that requires recurring wet periods.

“Groundwater can serve as a paleo-humidity, -precipitation proxy,” said Reika Yokochi, a geochemist at the University of Chicago and lead author of the paper. By using groundwater as a record of past climate conditions, researchers can use that information to better predict how precipitation might change in the future.

In the Negev, Yokochi said there is currently no groundwater recharge occurring. But in the geologic past, the area went through climate changes, including wetter conditions that renewed the aquifers.

“Krypton isotope dating of groundwater is exciting, as it opens a new window into past climatic conditions that was previously unavailable, or cloudy, with existing dating techniques.”Yokochi said that previous work in the Negev used carbon-14 (14C) to date groundwater reserves to about 30,000 years. The problem with using 14C is that the isotope extends back in time only 30,000–40,000 years, meaning the age of older water remained a mystery.

Using the noble gas isotope 81Kr solved this problem. Krypton-81 is found throughout the troposphere, where it mixes with raindrops.

“Once that water is isolated from the atmosphere [in the ground], there’s no more supply, and it decays,” Yokochi explained. “That’s when the clock starts.”

Yokochi said that 81Kr, with its half-life of about 230,000 years, allowed the team to measure the age of aquifers that are up to 1.3 million years old—a huge extension from 14C.

“Krypton isotope dating of groundwater is exciting, as it opens a new window into past climatic conditions that was previously unavailable, or cloudy, with existing dating techniques,” said Jennifer McIntosh, a hydrogeochemist at the University of Arizona. She was not involved in the research.

“This is one of the few studies to use groundwater as a record of paleoclimate beyond the Last Glacial Maximum,” said McIntosh.

Aging an Aquifer

In the past, Yokochi said that amassing enough krypton gas in a water sample required sampling about 200–300 liters. Bringing that much water back to a lab for analysis is “a lot to carry,” so Yokochi said she and her team used a field gas extraction device.

The team used atom trap trace analysis (ATTA) methods to measure krypton isotopes in the lab. The combination of field gas extraction and ATTA bolstered the team’s ability to collect water from 22 wells in the eastern Negev.

“Everything became more efficient and fast,” said Yokochi.

The researchers found that 81Kr data revealed two distinct groundwater recharge dates: one less than 38,000 years ago and a much older wet period about 360,000 years ago.

“This is the first case where we take a lot of data from a very small area, do the spatial distribution analysis, and talk about climate.”Pairing this information with hydrogen and oxygen isotope data from the samples, the team found that the younger aquifer was recharged with water sources from the Mediterranean, whereas the older wet period brought precipitation from the tropical Atlantic.

“Knowing the source of the water helps scientists understand past climatic conditions that led to groundwater recharge, and how vulnerable the aquifer is to future climate change,” said McIntosh. “This information can be used to inform paleoclimate models and aid in water management decisions.”

There have been other studies using 81Kr as a tracer, but Yokochi said that “this is the first case where we take a lot of data from a very small area, do the spatial distribution analysis, and talk about climate.”

McIntosh said she anticipates—and is excited for—krypton isotopes to be widely used in future studies.

“Knowing how ‘old’ groundwater is helps water managers evaluate how much water they can extract without significantly depleting the aquifer,” said McIntosh. “It can also help them determine how vulnerable the aquifer is to anthropogenic sources of contamination.”

—Sarah Derouin (@Sarah_Derouin), Freelance Journalist

In outer space, meteoroids are formed when collisions between objects produce fragments and are thus randomly shaped. But about a quarter of the large meteors that survive entry through Earth’s atmosphere to become meteorites are conical. A new study applying principles of fluvial dynamics in the lab to study the physics of meteor flight is shedding some light on how entry carves some shooting stars into cones. “The shapes of meteorites found on Earth are different from how they were shaped in space since they are melted, eroded, and reshaped by atmospheric flight.”

“The shapes of meteorites found on Earth are different from how they were shaped in space since they are melted, eroded, and reshaped by atmospheric flight,” said Leif Ristroph, a physicist at New York University and an author on the new study published in the Proceedings of the National Academy of Sciences of the United States of America. Many meteorites are amorphous blobs, he said, but “a surprising number, as many as 25%, are ‘oriented meteorites’ that look almost like perfect cones.”

Detailed observations of meteors in flight are rare, and little is known about the extreme forces that meteors sustain as they rocket through Earth’s atmosphere at speeds as fast as 70 kilometers per second. For a meteor to be shaped into a symmetrical cone it must hold a stable trajectory during flight.

“It makes intuitive sense that most meteors will tumble during flight and be randomly shaped, but we wanted to know why a quarter seem to maintain enough flight stability to be carved into cones,” Ristroph said.

Ristroph and colleagues sought to replicate some aspects of meteor flight in the lab by subjecting clay objects to flowing water. The first stage of experiments subjected model meteors held stationary by a rod to currents, and the second stage examined how differently shaped cones fell through columns of water.

“We looked at a whole family of cone shapes from very pointy, like a needle, to broad, like a disk, and everything in between. And what we found is that there was this Goldilocks kind of range of shapes in the middle where they are self-stabilizing,” said Ristroph.

Whereas narrow cones tended to flip over and broad cones fluttered back and forth, eroding the clay into more random shapes, the Goldilocks shape was able to stay straight and maintain a refined cone shape.

Six different flight patterns show how shape affects flight stability for cone-shaped objects. Flight pattern D shows stable flight for a “just right” Goldilocks cone shape. Credit: NYU Applied Math Lab

“It seems that the same aerodynamic forces that melt and reshape meteoroids in flight can also serve to help stabilize its position so that a cone shape can be carved and ultimately arrive on Earth,” Ristroph said.

Fluid, Cross-Disciplinary Work

The finding is a rare example of using lab-based experiments to study the physics of meteor flight, said Alexis Drouard, an astrophysicist at Aix-Marseille University in France who was not involved in the new study. “This is the first time I have seen fluid mechanics used to study the flight dynamics of meteors. It’s very interesting cross-disciplinary-type work.”

Whether a meteor survives its flight through the atmosphere is probably unrelated to its shape and more dependent on its initial size and angle of entry, as well as its composition, Drouard explained. “The more metal an object contains, the more likely it is it will survive entry.”

The density of the materials in the meteor is also important. “Looking at how density and different compositions affect flight stability could be an interesting next step for this line of research,” Drouard said.

Another next step might also be to study videos of meteors in flight to determine if rotation or stability can be detected by looking for changes in emitted light.

“In a high-speed video, presumably if the object is rotating, you might see some flickering, whereas if it’s stable, you might just see a bright streak,” Ristroph said. “As far as I know, nobody has been able to correlate those kinds of observations with flight orientation.”

—Mary Caperton Morton (@theblondecoyote), Science Writer

Ricardo Galvão, the recently ousted leader of Brazil’s agency that monitors deforestation in the Amazon basin, said that the Brazilian president’s attacks on scientific data that show sharp spikes in deforestation have “backfired on the government.”

“The whole world puts its attention on the Amazon now,” said Galvão, who was director of Brazil’s National Institute for Space Research (INPE) until he was removed from his post on 2 August.

“The leader of any country should be aware that in scientific matters there is no authority above the sovereignty of science.”Jair Bolsonaro, Brazil’s populist right-wing president who has worked to loosen environmental protections since taking office in January, falsely charged in July that INPE’s data on increased deforestation are lies. He also claimed without proof that INPE “seems to be in the service of some NGO,” or nongovernmental organization.

Galvão said he hopes that global attention on the Amazon, along with his own defense of science and sharp rebuke of Bolsonaro’s charges, will put up a roadblock against the government’s attacks on Brazilian science.

“The leader of any country should be aware that in scientific matters there is no authority above the sovereignty of science,” Galvão said.

Spikes in Deforestation

INPE’s satellite data show that deforestation in the Amazon in June 2019 was 920.21 square kilometers. This is an 88% increase from 2018, when fewer than 500 square kilometers were deforested.

The July 2019 increase in deforestation appears to be even more dramatic—reportedly 278% higher than July 2018, according to information widely reported by media in Brazil and elsewhere and attributed by the media reports to INPE data.

Philip Fearnside, an ecologist at the National Institute for Amazonian Research, told Eos that INPE had not yet released this July information on the agency website’s news section, “which appears to be a policy change” since Galvão’s ouster. Fearnside said that deforestation under Bolsonaro “is exploding.”

INPE’s Real-Time Deforestation Detection (DETER) system, which uses data from the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments on board NASA’s Aqua and Terra satellites, provides rapid deforestation alerts. On its website, INPE warns people not to draw simple conclusions or correlations from the data. The website explains that DETER is an expedient methodology “developed to support surveillance” of forest-clearing activities and that DETER data “should not be construed as a monthly rate of deforestation” because of monthly changes in cloud cover and satellite resolution.

A second INPE system, the Program for Calculating Deforestation of the Amazon (PRODES), provides more accurate annual estimates of deforestation.

“While it’s true that DETER is a preview [of the deforestation] trend and it’s not the final number, it’s also true that those trends must be taken seriously,” said Raoni Rajão, an environment management professor at the Federal University of Minas Gerais in Belo Horizonte, Brazil.

Bolsonaro’s Attacks on Science Agency

During a conversation with foreign journalists on 19 July, Bolsonaro claimed that INPE was lying about the deforestation data. Galvão told Eos that he was “really horrified” by Bolsonaro’s accusations against INPE. “I could not believe I was hearing what I was hearing.”

Other scientists in Brazil and elsewhere also told Eos that Bolsonaro’s remarks alarmed them.

“It’s very worrying having the president interfering in scientific matters and saying that INPE’s data were lies,” said Fearnside. “This is something that intimidates scientists all over the country and all of the institutions, which may have been the intention.”

“President Bolsonaro has tried to find a chink in the armor of DETER and blow it out of proportion, but the scientific community, both within Brazil and internationally, will stand firm that these attempts at obfuscation are baseless from a scientific perspective,” said Eric Davidson, who has conducted field research on the effects of land use change on the biogeochemistry of forest and pasture soils in the Brazilian Amazon since 1992.

“The recent uptick in deforestation reported by INPE is beyond the uncertainties of the method,” said Davidson, professor and director of the Appalachian Laboratory at the University of Maryland Center for Environmental Science in Frostburg. He is also a past president of AGU, which publishes Eos.

The uptick in deforestation “must be accepted as evidence with high confidence that Brazil’s legacy is in peril as a leader among nations for demonstrating how it is possible to reduce rates of tropical deforestation while simultaneously growing agricultural GDP.”

Speaking Out Against Bolsonaro’s False Charges

Galvão has countered the charges from the Bolsonaro administration by speaking out “to protect Brazilian science and to protect the dignity of our scientists,” Galvão said.

“Not only as a scientist but as a citizen of Brazil, I’m very concerned about the increasing rate of deforestation in the Amazon.”“Not only as a scientist but as a citizen of Brazil, I’m very concerned about the increasing rate of deforestation in the Amazon,” Galvão said.

The most important reason for the deforestation “is the message that the present government is giving, that the Amazon is ours, is not the concern for the world, [and] we can do with it what we want. This is a very serious message for people that want to deforest the Amazon,” he said. “They take [it] literally and they start invading and cutting trees and exploring minerals and all that.”

Galvão said that he was also disturbed by the government’s plan to contract with an outside company to provide data on deforestation. The current DETER and PRODES systems “give great credibility” to deforestation monitoring, he said. A private company could provide data that the government wants and not the real data.

INPE has been criticized in the past by other government officials, including the governor of the state of Mato Grosso in 2008 during the presidency of Luiz Inácio Lula da Silva, according to Galvão. However, Galvão said that instead of striking out against INPE, Lula resolved the situation by observing the deforestation by helicopter and confirming INPE’s data.

Killing the Messenger

Carlos Nobre, a renowned climate and Amazon researcher, told Eos that Galvão’s removal “is like the old saying, ‘kill the messenger of bad news,’” with the bad news in this case being data showing increased deforestation.

Galvão has been “almost like a hero defending science [and] defending the quality of INPE’s data,” said Nobre, who worked at INPE for more than 35 years until his retirement 3 years ago. Nobre currently is a senior researcher at the Institute of Advanced Studies, University of São Paulo. He is the international secretary of AGU.

Nobre said he is deeply concerned about the state of the Amazon and threats to science.

“These people, through social media, are spreading lies and fake science so effectively that we have to find ways to fight back.”If deforestation exceeds 20%–25% of the Amazon, calculations indicate the region will turn into a degraded savannah, said Nobre, who has extensively studied the risk of “savannization” in the Amazon. He added that the Amazon will face the same risk if warming exceeds 4°C in the region, even if deforestation is reduced.

Nobre said that with Galvão’s ouster, it is unclear whether INPE will be able to maintain budgets for its monitoring systems or maintain transparency in disseminating its data publicly.

In addition, Nobre voiced concern about a rising antiscience movement in Brazil.

“The empowerment of an antiscience movement really is very dangerous for humanity,” Nobre said. “These people, through social media, are spreading lies and fake science so effectively that we have to find ways to fight back.”

Some Hope Despite Attacks on Science and the Environment

Nobre said he is hopeful that over the course of a few years, the current antiscience sentiment will end “because society will start perceiving that moving in an antiscience direction is like…suicide.”

Fearnside told Eos that Bolsonaro already “had done a tremendous amount of damage in the environmental area, just in 7 months” and that “things are falling apart very quickly.” He noted, for instance, recent efforts to weaken the country’s environmental licensing law, which not only monitors use of pesticides and other pollutants but also could lead to loosened restrictions on upgrading existing roads, including roads through the Amazon.

“I hope Bolsonaro very seriously notes and changes his approach to global warming and to maintaining the Amazon jungle.”Fearnside said that people need to keep working on protecting the environment without losing hope or becoming complacent. “You have to stay focused” on improving the situation, he said.

Galvão and others added that they hope a strong global reaction to the spikes in deforestation will pressure Bolsonaro to change his policies. International concern for the Amazon, Galvão noted, could be bad for Brazilian business.

“Once the world gets the message that we are producing [products] by deforesting the Amazon, that’s going to stop completely our [exports],” said Galvão. “I hope Bolsonaro very seriously notes that and changes his approach to global warming and to maintaining the Amazon jungle.”

—Randy Showstack (@RandyShowstack), Staff Writer

At the end of its mission life, the orbit of the Cassini spacecraft was positioned to move ever closer to the planet, in what are known as the Grand Finale orbits. Nearly two dozen times, it squeezed between the innermost ring and the planet, continuing to make observations until its very last moments.

Using data from these orbits, Hunt et al. [2019] reveal a previously undetected electric current system deep in Saturn’s rings. They also construct a reasonable hypothesis for how it is connected to the planet’s upper atmosphere.  The “closure currents” in the ionosphere are comparable in size those in the auroral zone, which close field-aligned currents from the outer reaches of Saturn’s space environment. That is, this is substantial current system, but it is so close to the planet that it went undetected until these final orbits of the Cassini mission that sent the spacecraft inside the planetary rings.

Citation: Hunt, G. J., Cowley, S. W. H., Provan, G., Cao, H., Bunce, E. J., Dougherty, M. K., & Southwood, D. J. [2019]. Currents associated with Saturn’s intra‐D ring azimuthal field perturbations. Journal of Geophysical Research: Space Physics, 124. https://doi.org/10.1029/2019JA026588

—Mike Liemohn, Editor-in-Chief, JGR: Space Physics

Satellite capabilities to remotely estimate various ocean properties are continually increasing in maturity and scope. Sea surface temperature, height, and roughness; ocean vector winds; and bio-optical properties like chlorophyll concentration are now available on a routine and sustainable basis. These products are integral to operational applications for routine and event-driven environmental assessments, predictions, forecasts, and management. Yet these satellite observations are still underused, and they represent a huge potential for contributing to societal needs and the “blue economy.”

The first International Operational Satellite Oceanography (OSO) Symposium, organized and sponsored by the National Oceanic and Atmospheric Administration (NOAA) and the European Organisation for the Exploitation of Meteorological Satellites, was held at the NOAA Center for Weather and Climate Prediction. Approximately 150 people from 30 countries participated in the symposium. The day before the main meeting, 52 people attended an optional day of training related to satellite data processing and use.

Attendees shared ideas on how to better understand user needs and expectations, develop interoperability standards, and establish best practices that will lead to more universal use of ocean satellite data.The symposium brought together for the first time the international community of operational satellite oceanographic data and product providers and users. One intent of the symposium was to better define and understand the barriers, perceived or actual, hindering the use of satellite oceanographic observations. Another intent was to facilitate widespread incorporation of these observations into the value chain extending from their initial collection to their use across the range of operational applications.

This initial symposium, which consisted of plenary and poster sessions, focused on the upstream components of the value chain. These include the international community of satellite operators, information producers, and high- to intermediate-level users. Attendees shared ideas on how to better understand user needs and expectations, develop interoperability standards, and establish best practices that will lead to more universal use of ocean satellite data.

In the first five plenary sessions, invited speakers presented talks and answered audience questions during moderated panels. Each session loosely covered one of five themes:

redefining the operational paradigm linking data providers to information providers helping users find the information they need facilitating the end-to-end value chain understanding commercial provider needs

After a summation of these sessions, leaders in economics, applied research, the commercial sector, and future satellite mission planning offered their perspectives on the outlook for operational satellite oceanography.

The symposium adjourned after closing remarks and recommendations. A report summarizing the symposium, the identified challenges, and suggested recommendations is in preparation.

By all accounts, the symposium was a success. It marks the beginning of a biennial tradition in which those involved at all levels of the value chain, from data providers to users, will assemble to foster the use of operational satellite oceanographic data, products, applications, and services to provide greater societal benefits. The next OSO Symposium will convene in the vicinity of Frankfurt, Germany, during late spring to early summer 2021.

Author Information

Christopher W. Brown (christopher.w.brown@noaa.gov), Center for Satellite Applications and Research, National Oceanic and Atmospheric Administration, College Park, Md.; Veronica Lance, Earth System Science Interdisciplinary Center, Cooperative Institute for Climate and Satellites–Maryland, University of Maryland, College Park; and François Montagner, Remote Sensing and Products Division, European Organisation for the Exploitation of Meteorological Satellites, Darmstadt, Germany

The earthquakes that jolt us out of bed, the ones that trigger an instinctual urge to duck and cover, are powerful and potentially destructive.

But they’re also rare: For every magnitude 7.0 temblor, roughly a million magnitude 1.0 earthquakes occur.

Earthquake detection algorithms must be able to accurately disentangle these numerous, low-amplitude seismic signals from other sources of ground shaking such as aircraft passing overhead and waves crashing into coastlines. Now, researchers have analyzed the waveforms of wind-induced ground motion, work that will boost the performance of future earthquake detection algorithms, the scientists suggest.

Research on a Ranch

Christopher Johnson, a seismologist at the Scripps Institution of Oceanography in San Diego, Calif., and his colleagues collected data on a privately owned unused ranch situated atop the San Jacinto fault zone near Anza, Calif. Johnson and his team placed 40 geophones around the property’s stands of vegetation, old structures, abandoned machinery, and defunct airstrip. The coffee can–sized instruments, anchored to the ground with a roughly 12-centimeter-long metal spike, recorded ground velocity measurements 500 times per second from 9 February through 17 March 2018.

“We need to have a really good understanding of what all of these noise signals are.”The scientists wanted to better understand ground movement caused by wind energy being transferred into Earth through, for example, plant roots or building foundations. That’s important, researchers said, because wind-induced ground shaking—which affects roughly the top kilometer of Earth’s crust—is a source of noise in seismic records.

“We need to have a really good understanding of what all of these noise signals are,” said Johnson.

Seismic records are increasingly being mined to find new fault lines and better understand how one earthquake triggers others.

To test how ground shaking was correlated with wind strength, the scientists also measured wind velocity using an anemometer mounted near the ranch’s unused airstrip. They recorded an average wind velocity of roughly 2 meters per second and a maximum wind velocity of about 15 meters per second.

Masquerading as an Earthquake

Johnson and his collaborators found that gusts of wind stronger than a few meters per second were linked to ground shaking characterized by earthquake-like waveforms. The team examined the vertical and horizontal components of the wind-triggered shaking and found a consistently larger signal in the horizontal direction. That’s because the wind is pushing aboveground objects—like structures, vegetation, and machinery—with a shearing motion with respect to the ground, said Johnson.

The smallest events tell us a lot about the dynamics of fault zones and foreshock and aftershock sequences.Next, the researchers investigated the strength of the wind-triggered shaking at different locations on the ranch. They recorded the weakest signal on a hill and the strongest signal near a covered parking structure. These results make sense, said Johnson, because human-built structures are coupled to the ground through their foundations, which means that wind energy is efficiently transferred into the ground.

The scientists also found that wind-induced ground movement was sometimes strong enough to mask seismic signals arising from slipping faults. “About 6% of the day there are wind-induced ground motions with amplitudes greater than what we’re anticipating for microseismicity,” said Johnson. That’s bad news because there’s a lot that can be learned from these tiny earthquakes. “These tell a lot about the dynamics of fault zones and foreshock and aftershock sequences.”

Shaking Deep Down, Too

The scientists recorded wind-induced ground motion not only in the geophones resting on the ground but also in a 148-meter borehole that had been previously drilled and instrumented with a seismometer.

“We can see that [the wind energy] is going into the ground,” said Johnson. He and his colleagues published their findings last month in the Journal of Geophysical Research: Solid Earth.

These results are important, said Adam Ringler, a geophysicist with the U.S. Geological Survey at the Albuquerque Seismological Laboratory on Kirtland Air Force Base, N.M., not involved in the study. “By improving our understanding of how non-earthquake signals get recorded by sensors, we can improve our ability to detect small events and characterize them.”

In the future, Johnson and his team want to place more geophones near the San Jacinto fault zone. “We’ve been focusing on small areas, but you could imagine putting them out over 20 kilometers,” said Johnson. “They’re quick and easy to deploy.”

—Katherine Kornei, Freelance Science Journalist

In 2016, astronomers announced the discovery of a rocky, habitable, Earth-sized planet orbiting Proxima Centauri, the closest star beyond our solar system. A recent analysis now suggests that Proxima might also host a larger, colder planet.

“We call it Proxima c,” Mario Damasso, an astrophysicist at the Astrophysical Observatory in Torino, Italy, said about the potential discovery at a forum in April. “But it’s only a candidate. That’s very important to underline.”

If confirmed, this planet would make Proxima Centauri the nearest multiplanet system and challenge our understanding of how rocky planets larger than Earth form. Damasso discussed Proxima c on 19 August at the Extreme Solar Systems IV conference in Reykjavik, Iceland. This discovery is currently under peer review in Science Advances.

Bigger, Colder, Farther

Astronomers found the 2016 planet, Proxima b, using radial velocity (RV) measurements of the host star, which showed a characteristic wobble from the planet’s gravitational influence. Damasso and his team sought to validate Proxima b’s existence by analyzing the same data using a different method. They took particular care when accounting for Proxima’s stellar flares and spots.

Proxima Centauri is only slightly larger than Jupiter and is much smaller, cooler, and dimmer than the other two stars in that system (α Cen A and α Cen B). Because of its star’s temperature, Proxima c would be very cold and dim on the surface. Credit: European Southern Observatory, CC BY 4.0

“Stellar activity can hamper the radial velocity [analysis] because there can easily be present some signal from the stellar activity in the data,” Damasso said.

After accounting for Proxima’s stellar activity and Proxima b’s radial velocity signal, the team noticed a periodic signal leftover in the data. That signal suggested a second planet was tugging on Proxima. To make that signal, a planet would need to be at least 6 times Earth’s mass and orbit at about the same distance as Mars is from the Sun.

“Is this planet habitable? Well, not really. It’s quite cold.”“This detection is quite challenging, particularly because it’s made with only one technique,” Damasso said. “And the orbital period is very long, so it takes a long time to collect more data.”

“Is this planet habitable? Well, not really. It’s quite cold,” said team member Fabio Del Sordo, an astrophysicist at the University of Crete in Greece. “We estimated a surface equilibrium temperature of only 40 K,” which is −233°C. “So, clearly not habitable.”

A Long Road to Confirmation

At the April forum, University of Hawai‘i astronomer Lauren Weiss voiced concerns that a second Proxima planet might not be where or what the team thinks it is.

“In any system, you don’t know what planets there are [that] you haven’t found yet until you find them,” Weiss said. “They are an unknown unknown, which makes it very challenging to accurately model and fit radial velocities.”

She explained that the signal attributed to Proxima c could very well be a combination of other, weaker signals. “That maybe means that there are additional planets but not at the period at which [they’re] announcing the candidate,” she said.

“It’s possible that this planet migrated from somewhere else in the system.”Weiss recently told Eos, “I have seen no additional data supporting or falsifying the proposed orbit and minimum mass of the planet candidate Proxima Cen c” since the initial announcement in April.

With its currently calculated orbit, Proxima c would challenge our understanding about how planets that size form, Del Sordo said.

“Since low-mass stars are expected to host multiplanet low-mass systems, Proxima could certainly host other terrestrial planets we could not detect,” Damasso told Eos about his presentation in Iceland. “Analyzing the available RV data with methods different from that we used could reveal additional signal worthy of attention.”

“Models tell us that super-Earths tend to form around the snow line, but Proxima c at the moment is quite distant from the snow line,” he said. “It’s possible that this planet migrated from somewhere else in the system.”

“We plan to go on with radial velocity follow-up” as well as direct imaging with ground-based instruments, Damasso told Eos. “This is a necessary step to do since the orbital period of the candidate is [about] 5 years long.”

And with future astrometry data from the European Space Agency’s Gaia mission, “we should be able to measure the mass with 5% accuracy, which is great news for us,” Del Sordo said. “This will take place in a couple of years with the end-of-mission data.”

When it comes to confirming Proxima c’s existence, “it’s going to be a long road,” Weiss said.

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

Charged particles that spew into space as part of the solar wind create a protective magnetic bubble tens of billions of kilometers wide around the solar system. This bubble, called the heliosphere, plows through the harsh cosmic radiation of interstellar space.

Understanding the physics at the bubble’s edge, called the heliosheath, is not easy. The boundary is in constant flux and pushes out against the broader interstellar magnetic field that permeates our corner of the Milky Way. Only two spacecraft—Voyager 1 and 2, originally launched by NASA in 1977—have ever traversed the frontiers of our local bubble.

Now Dialynas et al. have combined Voyager data with observations from NASA’s Cassini mission, which orbited Saturn from 2004 to 2017, to gain more insight into this region of space. The researchers recognized that the missions, although launched 20 years apart, had collected complementary data. Voyager 1 and 2 had instruments that measured energetic ions as the craft crossed the heliosheath and exited the solar system. Cassini, meanwhile, was able to remotely observe energetic neutral atoms (ENAs) arriving in all directions from the heliosheath.

These two phenomena are related: ENAs come from the heliosheath, where fast solar wind protons collide with neutral hydrogen atoms from interstellar space and “steal” an electron from the interlopers. The Voyager probes took in situ measurements of the parent heliosheath proton distributions as they passed through this region. Meanwhile, the protons with newly added electrons become ENAs and zip off in all directions.

The synergy among the spacecrafts’ observations allowed the researchers to use Voyager data from the heliosheath to ground truth and calibrate ENA data from Cassini, which was more sensitive to lower energetic particles than Voyager was. Together, the spacecraft extended data on the intensity of both ENAs and ions to include a broader range of energies, which gave the team a window into the physics in the heliosheath as the solar wind and interstellar medium press against each other.

The researchers found that in the energy range considered in their study (>5 kiloelectron volts), lower-energy ions with energies between about 5 and 24 kiloelectron volts played the largest role in maintaining the pressure balance inside the heliosheath. This allowed the team to calculate the strength of the magnetic field and the density of neutral hydrogen atoms in interstellar space—about 0.5 nanotesla and 0.12 per cubic centimeter, respectively.

On the basis of calculations from Voyager 2 data, the researchers predict that the heliopause, the outer boundary of the heliosheath, is located roughly 18 billion kilometers from the Sun, or 119 times the distance from the Sun to the Earth—right where Voyager 2 found it in November 2018.

Furthermore, the finding that the lower-energy ions dominate the pressure balance in the heliosheath means that space physicists will have to rethink their assumptions about the energy distribution of such particles in the heliosheath. (Geophysical Research Letters, https://doi.org/10.1029/2019GL083924, 2019)

—Mark Zastrow, Freelance Writer

 

In 1972, during the waning years of the Vietnam War, U.S. military pilots flying south of Haiphong harbor in North Vietnam saw something unexpected. Without explanation and without warning, over two dozen sea mines suddenly exploded.

Although the phenomenon was never officially explained, it piqued the interest of geospace scientist Delores Knipp.

Credit: Delores Knipp

Knipp is a research faculty member at the Ann and H. J. Smead Aerospace Engineering Sciences Department at the University of Colorado Boulder and editor in chief of the AGU journal Space Weather.

She originally wanted to be a meteorologist and joined the Air Force Reserve Officer Training Corps in college with the goal of staying in the military for 4 years to pay off her student loans. Twenty-two years later, she retired after a career with the Air Force studying weather and space weather.

Being a scientist in the Air Force presented Knipp with some unique opportunities to educate her colleagues, specifically answering questions like “What is dark?” It might sound silly, but it’s a big deal when determining flight schedules.

But Knipp really started diving into some of the more mysterious stuff after she retired.

In this Centennial episode of Third Pod from the Sun, Knipp provides a unique perspective about the role of space weather in shaping global policy and conflicts. From a chance phone call from a colleague encouraging her to solve a decades-old mystery to discovering clues in the obituary of an Air Force commander, Knipp unravels some of the biggest space weather mysteries that many of us have never heard of.

This episode was produced by Shane M. Hanlon and mixed by Collin Warren.

—Shane M. Hanlon (shanlon@agu.org; @EcologyOfShane), Program Manager, Sharing Science (@AGU_SciComm), AGU

Absolute measurements of turbulence in the atmosphere are difficult to obtain, and it is even harder to get large amounts of reliable observations. Ko et al. [2019] present turbulence characteristics derived from a large data set of twice-daily, high-vertical-resolution (approximately 5 meters) radiosonde balloon measurements at 68 stations over the United States, using several years of data. Analysis is based on deducing unstable thermodynamic vertical structure using the so-called “Thorpe analysis”, which is becoming widely accepted as a true measure of turbulent energy dissipation rates.

Results in this study highlight stronger turbulence and energy dissipation in the troposphere than in the stratosphere, with a strong seasonal cycle and geographic structure in troposphere statistics (see map above). These results provide novel characterization of turbulence behavior on large spatial and temporal scales, which are useful for aviation turbulence studies and for improving numerical weather prediction models.

Citation: Ko, H.‐C., Chun, H.‐Y., Wilson, R., & Geller, M. A. [2019]. Characteristics of atmospheric turbulence retrieved from high vertical‐resolution radiosonde data in the United States. Journal of Geophysical Research: Atmospheres, 124. https://doi.org/10.1029/2019JD030287

—William J. Randel, Editor, JGR: Atmospheres

On 2 July 2019, 26 AGU member scientists were awarded the Presidential Early Career Award for Scientists and Engineers (PECASE) by the White House Office of Science and Technology Policy. This is “the highest honor bestowed by the United States Government to outstanding scientists and engineers who are beginning their independent research careers and who show exceptional promise for leadership in science and technology.”

The diverse cohort of AGU awardees hails from across the United States and is working in a variety of Earth and space science fields, including volcanology, astrobiology, and polar science. The 2019 AGU member award recipients are as follows:

Eric Anderson, Great Lakes Environmental Research Laboratory, National Oceanic and Atmospheric Administration (NOAA)

Kristina J. Anderson-Teixeira, ForestGEO Ecosystems & Climate Program, Smithsonian Institution

Annemarie Baltay, Earthquake Science Center, U.S. Geological Survey (USGS)

Laura Barge, NASA Jet Propulsion Laboratory, California Institute of Technology

Whitney Behr, Department of Earth Sciences, ETH Zürich

Lynn Carter, Lunar and Planetary Laboratory, University of Arizona

Nicolas Cassar, Nicholas School of the Environment, Duke University

Matthew Dietrich, Department of Earth and Environmental Sciences, Vanderbilt University

Shawn Domagal-Goldman, Sciences and Exploration Directorate, NASA Goddard Space Flight Center

Brian Ebel, Center for Water, Earth Science and Technology, University of Colorado Boulder

Erika Hamden, Department of Astronomy and Steward Observatory, University of Arizona

Andrew Hoell, Earth System Research Laboratory, NOAA

Tara Hudiburg, College of Natural Resources, University of Idaho

Matthew Kirwan, Virginia Institute of Marine Science

Erika Marin-Spiotta, Department of Geography, University of Wisconsin–Madison

Brian McDonald, Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder

Richard Moore, NASA Airborne Science Program, NASA Langley Research Center

Maitane Olabarrieta, Coastal and Oceanographic Engineering Department, University of Florida

John Reager, NASA Jet Propulsion Laboratory, California Institute of Technology

Andrew Rollins, Earth System Research Laboratory, NOAA

Yolanda Shea, CLARREO Science Definition Team, NASA Langley Research Center

Jeffrey Snyder, School of Earth, Environment and Society, Bowling Green State University

Jenny Suckale, School of Earth, Energy, and Environmental Sciences, Stanford University

Aaron Wech, Volcano Science Center, USGS

Heather Wright, Volcano Disaster Assistance Program, Cascades Volcano Observatory, USGS

Kelly Wrighton, College of Agricultural Sciences, Colorado State University

“The PECASE is an incredible honor, but really it signifies how fortunate I am to have such an inspiring and creative group of mentors and colleagues from NOAA and beyond,” said award recipient Eric Anderson.

Awardee Lynn Carter said the award recognizes that “my work with radar remote sensing and radar technology development is valuable to the agency and a direction to keep going in the future. Receiving this award is also an inspiring reminder to persevere and to continue to help those coming up in the field achieve their goals as well.”

“On behalf of AGU, I wish to congratulate all those receiving this richly deserved award. The innovation, expertise, and dedication of these early-career scientists to advance human understanding in the Earth and space sciences is both inspiring and uplifting,” said AGU CEO/executive director Chris McEntee. “AGU looks forward to working with this diverse group of researchers as they continue to grow in their careers for years to come.”

Given once within a scientist’s career, the award is meant to help propel innovation in science and technology, elevate public awareness of and appreciation of the importance of science and engineering careers, shed light on the pivotal work of federal scientific agencies, and strengthen the convergent science connections connecting fundamental research and policy goals. Each recipient receives funding from their agency for up to 5 years to advance his or her research. This year’s recipients were honored at a ceremony in Washington, D.C., on 25 July.

—Joshua Speiser (jspeiser@agu.org), Manager of Strategic Communications, AGU

23 August 2019: The article was updated to include all AGU members who received the award.

Climate change caused by past and ongoing emissions from fossil fuel burning poses sizable risks for current and future generations through its impacts on multiple interacting sectors, including, for example, food and water supplies and public health [O’Neill et al., 2017].

The extent of these risks is subject to deep uncertainties and tipping points, suggesting the need for flexible approaches to climate adaptation. One example of a deep uncertainty in our understanding of climate is the degree to which local and regional storm surge intensities are modulated by a warming climate [Lee et al., 2017; Wong et al., 2018].

In climate risk management, these uncertainties often affect estimates of potentially damaging impacts, thus amplifying the importance of the uncertainties [Wong et al., 2017a].

Even with strong mitigation of anthropogenic climate forcing, communities will still need to adapt to impending changes resulting from historical greenhouse gas emissions.Even with strong mitigation of anthropogenic climate forcing, communities will still need to adapt to impending changes resulting from historical greenhouse gas emissions. Successful strategies require the right information, such as observations of relevant environmental indicators, or signposts, to trigger needed changes in the approach, and updated risk assessments that account for new information.

Fundamental Earth science research provides a foundation for supplying this information. Integrating research about regional- and global-scale Earth system processes into adaptation planning can help identify strategies to manage climate risks in the face of the uncertainties to ensure sustainable and resilient communities. We illustrate this point with an example of decision-making to adapt to sea level rise in Norfolk, Va.

Protecting Norfolk: A Case Study

Consider the decision of how high to build a levee to help protect Norfolk, which sits along the Elizabeth River at the south end of the Chesapeake Bay. Suppose that decision-makers seek flood defense systems to limit the chance that by the year 2070, floodwaters will overtop the levee to 1% in a given year, corresponding to an event with a 100-year return period. Planning to meet this target requires projections of sea level rise and storm surge. These projections hinge critically on assumptions about climate policies and the strength of physical feedback mechanisms governing, for example, ice sheet and storm surge dynamics [Wong et al., 2017a].

Fig. 1. Effects of deep uncertainties (about storm surge dependence on global mean temperatures) and positive feedbacks (triggering of rapid West Antarctic melting dynamics) on projected coastal flooding by 2070 modeled for Norfolk, Va. (a) Water height anomalies in 2070 (relative to 2015) plotted against return periods for four different sets of model assumptions. (b) Maximum water height of a flood event with a 100-year return period for each modeled scenario. Changing storm surge distributions are based on changes in global mean temperature. Mean sea level and global mean temperature projections were obtained using the Building blocks for Relevant Ice and Climate Knowledge (BRICK) sea level rise emulator from Wong et al. [2017b]. Storm surge models were calibrated using data from Sewells Point in Norfolk. Land subsidence estimates are from Kopp et al. [2014].According to our modeling, making seemingly reasonable assumptions about future flooding on the basis of recent historical tide gauge records alone could lead planners to suggest a levee height of roughly 2.5 meters (Figure 1, green curve). However, this choice of levee height could result in drastically higher (and arguably unacceptable) flooding risks if some of these assumptions fail. For example, if Earth’s ice sheets respond rapidly and nonlinearly to increased climate forcing (as they have likely done in the past [Wong et al., 2017a] and may be doing now [Joughin et al., 2014]) and if storm surge frequency and/or intensity increase with a warming climate (which may be consistent with existing evidence [Lee et al., 2017]), then the projected probability of floodwaters overtopping a 2.5-meter-tall levee rises to just over 5% per year (Figure 1, pink curve) in this example analysis. In other words, what might have been considered a once-in-a-century flood event would occur approximately every 19 years on average.

An alternative might be to build a levee high enough to defend against the perceived worst-case scenario. Using an example worst-case assumption established by the National Oceanic and Atmospheric Administration in the case of Norfolk might lead to construction of a levee roughly 4 meters tall [Sweet et al., 2017]. This strategy might be logistically infeasible, however, and would likely require very large investments that some might feel could be better spent elsewhere.

How can we manage trade-offs between competing concerns given the deep uncertainties in our knowledge of climate? One approach is to hedge in the short term against immediate and foreseeable risks, then adapt as new information becomes available. By analogy, if a doctor tells you that you have an increased risk of heart disease, it might be prudent to adapt your behavior initially by moderately modifying your diet and exercise habits while leaving open the option to use more intensive approaches, such as prescription medication, if your perceived risk does not decrease sufficiently in the future.

Health risks can be better managed with sustained observations (checkups, blood tests, etc.) and analyses. Similarly, climate risks can be better managed with sustained Earth observation systems and research, so that science can inform decisions. What does this mean for designing, implementing, and resourcing mission-oriented basic science?

For coastal flood risk management, several unknowns can be addressed by analyzing basic Earth science questions: (1) What are the impacts of possible future greenhouse gas emissions trajectories, including on relatively low probability but high-risk events? (2) Will the West Antarctic Ice Sheet (WAIS) collapse, and if so, on what timescale [Joughin et al., 2014]? (3) What would be the resulting contribution of WAIS collapse to local sea level changes? (4) Are there detectable changes in the frequency and severity of storm tides? (5) Are storm tracks changing as a result of climate change? (6) What regions and metropolitan areas are more likely to be affected?

Designing adaptive strategies that can react to new information from Earth science observations can drastically improve future outcomes in the event of potentially damaging flood events.Designing adaptive strategies that can react to new information from Earth science observations can drastically improve future outcomes in the event of potentially damaging flood events [U.S. Army Corps of Engineers, 2014]. Current mitigation measures can be planned with an eye toward flexibility and expandability so that the full suite of appropriate options is available in the future. As an example, while new levees are being built or existing levees heightened, it might also be prudent to build them so they could be widened and further heightened in the future. In the Norfolk example, consider again a levee designed to defend against floods with return periods shorter than 100 years as of 2070 when the levee height—2.5 meters—is based only on linear extrapolation from the historical record (Figure 1, green curve). By comparison, even under relatively conservative model assumptions, considering a consistent storm surge pattern out to 2070 but ignoring the potential for accelerated West Antarctic melting (Figure 1, orange curve), that 2.5-meter levee would protect only against floods with a 46-year average return period, less than half of the target standard.

Integrating disciplines such as Earth science, statistics, and decision analysis into adaptation planning can help identify signposts that can be used to design monitoring systems and trigger potentially needed changes in strategy [Haasnoot et al., 2013; Weatherhead et al., 2018]. A simplified and potentially effective adaptive approach at Sewells Point, near Naval Station Norfolk, might involve the following steps:

First, heighten the levee in stages over the next few decades to maintain a 100-year protection standard against well-characterized risks—say, the nonaccelerated sea level rise scenario in Figure 1 (orange curve)—with enough width built in to increase the height in the future if necessary. Second, plan for transitions between scenarios (e.g., from orange to blue to pink in Figure 1) to avoid being locked into a single approach. And if the projected levee height needed to meet the target protection standard in certain scenarios is more than what might be tolerated on the basis of cost or aesthetic objections, the possibility of using other resiliency measures—elevating houses, property buyouts, or land use changes, for example—should be left open. Third, monitor signposts, such as changes in ice sheet dynamics and trends in regional tide gauge records, for indications that the local flood risk could change. Finally, update risk assessments and mitigation strategies with this new information.

Effective Adaptation Requires Investment

Such adaptive strategies can drastically reduce risks and/or costs [Haasnoot et al., 2013; Yohe, 1991], but they do require sustained investment to realize these benefits. The example outlined above requires investments in sustained Earth observations and analysis aimed at understanding and early detection of climate change impacts. Remote sensing observation platforms provide broad-based benefits [Weatherhead et al., 2018], increasing the economic value of the gathered information. The benefits of such information are regional in the case of storm surge trends and global in relation to ice sheet observations.

Ultimately, the selection of a strategy requires balancing and compromising among diverse stakeholder perspectives and objectives.Finally, various adaptation strategies can be analyzed and compared to shed light on the trade-offs associated with choosing among the strategies (trade-offs related to costs, externalities like property values, and flood hazards, among others). Ultimately, the selection of a strategy requires balancing and compromising among diverse stakeholder perspectives and objectives. Multiobjective decision analysis can help identify strategies that best navigate the often hard trade-offs that arise [Kasprzyk et al., 2013], and careful articulation of objectives and trade-offs helps to improve the transparency of the decision-making process.

This opinion focuses on the issues of sea level rise and flooding affecting one example site. Similar plans would be required to address a wide range of other issues posed by the changing climate, which are likely to become more challenging if mitigation measures are not implemented.

Efforts to defend against climate-related risks benefit from sustained commitments to getting the right science, getting the science right, and getting the science to the decision-makers. Investments in basic Earth science observations and research enhance our ability to identify meaningful signposts for adaptation, to understand the risks associated with tipping points, and to realize the benefits of sound risk management strategies.

Acknowledgments

We thank Tony Wong, Robert Nicholas, Kelsey Ruckert, Nancy Tuana, and Robert Lempert for their contributions. This work was supported by the Penn State Center for Climate Risk Management. Any opinions, findings, conclusions, and recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the funding entity. Any errors and opinions are those of the authors. All model codes, analysis codes, data, and model output used for analysis are freely available at github.com/vsrikrish/SPSLAM and are distributed under the GNU General Public License. The data sets, software tools, and other resources on this website are provided as is, without warranty of any kind, express or implied. In no event shall the authors or copyright holders be liable for any claim, damages, or other liability in connection with the use of these resources. V.S., R.A., and K.K. conceptualized the commentary and wrote the paper; V.S. wrote the analysis codes. The authors are not aware of any competing interests.

The oil and gas industry’s practice of pumping wastewater fluids underground for disposal has been implicated in the dramatic uptick in earthquakes in the central United States. Now a new study has found a correlation between the increasing depth of the earthquakes and the rate at which these fluids descend through Earth’s crust, a finding that could have implications for how such fluids are regulated.

The blue line shows the number of earthquakes in Oklahoma over magnitude 2.5 rising from dozens to hundreds a year in the mid-2000s, after underground wastewater disposal became common practice. The red arrow shows the earthquakes striking deeper over time as wastewater continues to sink into fault systems. Credit: Ryan Pollyea

Over the past decade, earthquakes in the central United States greater than magnitude 3.0 have increased dramatically because of disposal of oil field wastewater into deep geologic formations. Injecting these fluids under pressure can destabilize faults and, in some places, trigger hundreds of induced earthquakes a year over magnitude 3.0, some as large as the magnitude 5.8 quake that struck Pawnee, Okla., in 2016.

Studying the mechanisms by which injected fluids trigger earthquakes has been hampered by a lack of accessible information about the compositions of the wastewater fluids, said Ryan Pollyea, a hydrogeologist at Virginia Polytechnic Institute and State University in Blacksburg and lead author of the new study, published in Nature Communications. “So much of that data is proprietary information, held by the oil and gas companies,” he said.

To assess how the density of the fluids may influence their descent, Pollyea and colleagues turned to a database maintained by the U.S. Geological Survey that includes typical compositions of wastewater fluids. Some of these fluids have very high dissolved salt content, Pollyea said, making the fluids denser and heavier than groundwater found in fault systems.

“We developed computer models showing that oil field wastewater tends to sink when it has a higher dissolved solids concentration—and thus, higher density—than fluids deep within the Earth’s crust,” he said. As this high-density wastewater sinks, it displaces the lower-density fluids that naturally reside in the faults and increases fluid pressure, potentially triggering fault movements.“This [study] provides compelling evidence that high-density wastewater is sinking and causing earthquakes to get deeper within the study areas.”

The team also analyzed earthquake data collected across several Oklahoma counties and found that earthquakes are getting deeper at the same rate high-density wastewater sinks—by about half a kilometer a year. “This provides compelling evidence that high-density wastewater is sinking and causing earthquakes to get deeper within the study areas,” he said.

Earthquake data collected across a broad region of northern Oklahoma and southern Kansas between 2013 and 2018 have demonstrated that the overall earthquake rate has been declining since 2016. Pollyea and colleagues found that although that may be the case overall, the number of earthquakes over magnitude 4.0 is increasing in number. These larger quakes tend to strike at depths below 4 kilometers. “This is likely the result of wastewater sinking and driving up fluid pressure at greater depths,” he said.

Previous studies have not considered the role of wastewater fluid density on fault systems, said Shemin Ge, a hydrogeologist at the University of Colorado Boulder who was not involved in the new study. “In the past, we have generally thought of wastewater as just water. This study adds a new dimension: What happens when the wastewater is denser than water? How does it move through the Earth? It’s a very interesting new perspective.”

The new study also suggests that fluids pumped underground can trigger earthquakes for over a decade after pumping stops, Pollyea said, as the fluids continue to sink to depths beyond 8 kilometers. “Our models also show that high-density oil field wastewater will continue sinking and increasing fluid pressure for over a decade after disposal operations cease,” he said.“We need more cooperation and collaboration from industry if we’re going to understand how these fluids interact with the fault environment.”

Going forward, both Pollyea and Ge would like to see more transparency from oil and gas companies about the contents of wastewater fluids. “The composition of these fluids and other pertinent information should be incorporated into the permitting and regulatory process,” Pollyea said. “If more of that data was available, we could learn a lot more about the mechanisms driving these earthquakes.”

“We need more cooperation and collaboration from industry if we’re going to understand how these fluids interact with the fault environment,” Ge said. “It’s surprising how little we know about [wastewater fluids] and yet they have such a significant impact on huge regions of the country, an impact that this study shows will not immediately go away after they stop injecting.”

—Mary Caperton Morton (@theblondecoyote), Science Writer

Each year since 1962, AGU has elected as Fellows members whose visionary leadership and scientific excellence have fundamentally advanced research in their respective fields. This year, 62 members will join the 2019 class of Fellows.

This honor is bestowed on only 0.1% of AGU membership in any given year.AGU Fellows are recognized for their scientific eminence in the Earth and space sciences. Their breadth of interests and the scope of their contributions are remarkable and often groundbreaking. Only 0.1% of AGU membership receives this recognition in any given year.

On behalf of AGU’s Honors and Recognition Committee, our Union Fellows Committee, our section Fellows committees, AGU leaders, and staff, we are immensely proud to present the 2019 class of AGU Fellows.

We appreciate the efforts of everyone who provided support and commitment to AGU’s Honors Program. Our dedicated AGU volunteers gave valuable time and energy as members of selection committees to elect this year’s Fellows. We also thank all the nominators and supporters who made this possible through their dedicated efforts to nominate and recognize their colleagues.

Honor and Celebrate Eminence at Fall Meeting

At this year’s Honors Tribute, to be held Wednesday, 11 December, at Fall Meeting 2019 in San Francisco, Calif., we will celebrate and honor the exceptional achievements, visionary leadership, talents, and dedication of 62 new AGU Fellows.

Please join us in congratulating our 2019 class of AGU Fellows, listed below in alphabetical order.

—Robin Bell, President, AGU; and Mary Anne Holmes (unionfellows@agu.org), Chair, Honors and Recognition Committee, AGU

 

Zuheir Altamimi, Institut National de l’Information Géographique et Forestière and Institut de Physique du Globe de Paris

Ronald Amundson, University of California, Berkeley

Jonathan Bamber, University of Bristol

Barbara A. Bekins, U.S. Geological Survey

Jayne Belnap, Southwest Biological Science Center, U.S. Geological Survey

Thomas S. Bianchi, University of Florida

Jean Braun, GFZ Helmholtz Centre Potsdam, and Institute of Earth and Environmental Sciences, University of Potsdam

Ximing Cai, University of Illinois at Urbana-Champaign

Ken Carslaw, University of Leeds

Benjamin F. Chao, Institute of Earth Sciences, Academia Sinica

Patrick Cordier, Université de Lille

Rosanne D’Arrigo, Lamont-Doherty Earth Observatory of Columbia University

Eric A. Davidson, Appalachian Laboratory, University of Maryland Center for Environmental Science

Gert J. de Lange, Utrecht University

Andrew Dessler, Texas A&M University

Michele K. Dougherty, Imperial College London

Joseph R. Dwyer, University of New Hampshire

James Farquhar, University of Maryland, College Park

Mei-Ching Fok, NASA Goddard Space Flight Center

Piers Forster, University of Leeds

Christian France-Lanord, CNRS Université de Lorraine

Antoinette B. Galvin, University of New Hampshire

Peter R. Gent, National Center for Atmospheric Research

Taras Gerya, ETH Zurich

Dennis Hansell, University of Miami

Ruth A. Harris , Earthquake Science Center, U.S. Geological Survey

Robert M. Hazen, Carnegie Institution for Science

Kosuke Heki, Hokkaido University

Karen Heywood, University of East Anglia

Russell Howard, United States Naval Research Laboratory

Alan G. Jones, Complete MT Solutions Inc. and Dublin Institute for Advanced Studies

Kurt O. Konhauser, University of Alberta

Sonia Kreidenweis, Colorado State University

Kitack Lee, Pohang University of Science and Technology

Zheng-Xiang Li, Curtin University

Jean Lynch-Stieglitz, Georgia Institute of Technology

Kuo-Fong Ma, National Central University and Academia Sinica

Reed Maxwell, Colorado School of Mines

John W. Meriwether, Clemson University (Emeritus) and New Jersey Institute of Technology

Son V. Nghiem, Jet Propulsion Laboratory, California Institute of Technology

Yaoling Niu, Durham University

Thomas H. Painter, Joint Institute for Regional Earth System Science and Technology, University of California, Los Angeles

Beth Parker, University of Guelph

Ann Pearson, Harvard University

Graham Pearson, University of Alberta

Lorenzo M. Polvani, Columbia University in the City of New York

Peter Reiners, University of Arizona

Yair Rosenthal, Rutgers University–New Brunswick

Osvaldo Sala, Arizona State University

Edward (Ted) Schuur, Northern Arizona University

Sybil Seitzinger, University of Victoria

Toshihiko Shimamoto, Institute of Geology, China Earthquake Administration

Adam Showman, University of Arizona

Alexander V. Sobolev, Institut des Sciences de la Terre, Université Grenoble Alpes, and Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences

Carl Steefel, Lawrence Berkeley National Laboratory

John Suppe, University of Houston

Karl E. Taylor, Lawrence Livermore National Laboratory

Meenakshi Wadhwa, Arizona State University

Michael Walter, Carnegie Institution for Science

John Wettlaufer, Yale University and Nordic Institute for Theoretical Physics

Chunmiao Zheng, Southern University of Science and Technology, Shenzhen

Tong Zhu, Peking University

Happy Birthday, Smokey! As summer camping trips end and fall fire seasons begin, it’s a good time to remember that only YOU (and I) can prevent wildfires. —Caryl-Sue, Managing Editor

 

Girl Scouts Emphasize STEM Education

At a briefing on Capitol Hill, Sydne Jenkins, 16, spoke about the benefits and opportunities provided by Girl Scout STEM programs. Credit: Randy Showstack

Girls just wanna have space science badges! That’s how the song goes, right? I’m so excited that @girlscouts can (officially) be explorers, adventurers, investigators, researchers, and experts in space sciences! —Kimberly Cartier, Staff Writer

 

The Cows That Could Help Fight Climate Change. Through no fault of their own, cattle and other livestock contribute substantially to anthropogenic greenhouse gas emissions—14.5% by one prominent estimate!—mainly in the form of methane. This is an interesting read about a variety of ways researchers are looking to decrease cattle carbon emissions, including an effort to vaccinate the animals against methane-producing gut microbes. #CattleCounteringClimateChange (Of course, another route to the same end is for us omnivores—myself included—to cut back on our beef consumption.) —Timothy Oleson, Science Editor

 

An Italian Volcano Turned Out to Be a Fraud. “It might sound improbable that an impostor ended up sneaking into the volcanological equivalent of the Library of Alexandria.” Janine Krippner is one of the keepers of the Smithsonian Institution’s volcano registry, and this is the story about how she discovered a fake. —Heather Goss, Editor in Chief

 

The Most Boring Chemical Element (paywalled)

This is one of our favorite versions of the periodic table, illustrating each element’s natural occurrence or familiar human use. Click image for larger version. Credit: Keith Enevoldsen, CC BY-SA 4.0

What is the most boring element? This Nature Chemistry comment will keep you on your toes in its takedown of the periodic table. —Jenessa Duncombe, Staff Writer

 

Seeking Stardust in the Snow. Fallen stardust lets us relive “local” stars going supernova over the past 20 million years. I think we need a video of that! —Liz Castenson, Editorial and Production Coordinator

 

Is Grass-Fed Beef Really Better for the Planet? Here’s the Science. “For the environmentally minded carnivore, meat poses a culinary conundrum.” The article doesn’t provide all the answers, but it gave me—an omnivore and a self-confessed foodie—some information to chew on. —Faith Ishii, Production Manager

 

Expect a Busier-Than-Normal Hurricane Season, NOAA Says. Following one of the hottest Julys on record and flood-inducing rainstorms, the United States and other Atlantic nations now face an increased possibility of a highly active hurricane season. El Niño has dissipated, and the National Oceanic and Atmospheric Administration recently put out a revised forecast. —Tshawna Byerly, Copy Editor

The concept of blades of ice sculpted by the Sun sounds otherworldly, and it is. Such blades have been detected on Pluto and are believed to exist on Jupiter’s moon Europa. But they also form high in the Andes mountains of South America.

Now researchers have spotted microbial life on the earthly versions of these icy spires. This discovery has astrobiological implications, the science team behind it suggests: Ice might provide a toehold for life in the solar system.

“What’s This?”

Steve Schmidt, a microbial ecologist at the University of Colorado Boulder, and his colleagues didn’t set out to study penitentes, which form when sunlight strikes patches of snow, causing it to sublimate. (The features’ Spanish name refers to their resemblance to white-robed monks doing penance.) In March 2016, Schmidt and his team were hiking up Llullaillaco, a dormant stratovolcano on the border between Chile and Argentina, and paused to rest at an elevation of roughly 5,300 meters near a field of penitentes. Schmidt remembers a team member seeing pinkish red smudges on roughly meter tall penitentes and asking, “What’s this?”

The smudges looked biological, but they were also rare: Only about 0.1% of the penitentes in the field had any coloration, Schmidt said. “You could easily walk by and not see it.”

The scientists weren’t planning to sample the penitentes, but seeing the unusual color piqued their interest. They retrieved sterile spoons from their packs and, over the course of a few hours, collected five samples of the pinkish red ice from the sides of several penitentes and the “wells” between them.

Snow Algae

Back in the laboratory at the University of Colorado Boulder, the researchers analyzed the samples’ DNA.

By comparing the samples’ DNA sequences with sequences from known organisms, the scientists found a perfect match with strains of the snow algae Chlamydomonas nivalis taken from Mount Kilimanjaro, the Swiss Alps, and Antarctica. But not all of the DNA from the penitentes matched Chlamydomonas nivalis—some probably came from previously unknown species of snow algae belonging to another genus, Chloromonas, and perhaps even other unknown genera, the team concluded.

“I think it’s the first discovery of microbes on penitentes,” said Schmidt. “Nobody ever thought to look for them.” These results were published in June in Arctic, Antarctic, and Alpine Research.

Sunscreen for Algae

“It’s sort of a sunscreen for the algae.”The red coloration of the snow algae is more than just eye-catching—it likely helps protect the algae from the intense sunlight that blasts the upper reaches of Llullaillaco, said Schmidt. Red-hued pigments like carotenoids within red varieties of snow algae—such as Chlamydomonas nivalis—dissipate the Sun’s energy by radiating away heat.

“It’s sort of a sunscreen for the algae,” said Schmidt.

By reemitting the Sun’s radiation, snow algae also warm up their surroundings and melt the ice around them to create liquid water.

“You have this oasis where there’s abundant life,” said Schmidt.

John Moores, a planetary scientist at York University in Toronto, Canada, not involved in the research, agrees. “The environment within the small-scale nooks and crannies of those exposures could be more clement from an astrobiological perspective than the surface more broadly.”

Snow algae might also play a role in the formation of Llullaillaco’s penitentes, researchers suggest. Previous results have shown that snow algae can have the same effect as dusty debris on a snowy surface, absorbing more sunlight than bare snow alone.

By kick-starting sublimation, snow algae may contribute to the formation of penitentes, Schmidt and his team hypothesized. An important next step will be determining whether snow algae are present during different phases of penitente growth, the researchers concluded.

Limits of Life

Earthly penitentes harbor life, Schmidt and his team showed, but what about extraterrestrial penitentes? These features have been spotted on Pluto, where they’re composed of nitrogen and methane rather than water, and are inferred to exist on Jupiter’s moon Europa.

To help answer that question, Schmidt and his colleagues want to understand the environmental limits of microbes like snow algae. Penitentes can be found all the way up to the top of Llullaillaco, the second-highest active volcano in the world (6,739 meters). Conditions get progressively harsher near the summit, and Schmidt and his team want to return to South America to look for microbes at a range of elevations.

That’ll help answer just how much ultraviolet radiation and aridity life can handle, said Schmidt. “At what elevation can you not find them?”

—Katherine Kornei (@katherinekornei), Freelance Science Journalist

On 13 August, a coalition of states and cities sued the Trump administration over new regulations on power plants that would weaken emissions restrictions proposed by the Obama administration.

The 22 states and seven cities filing suit assert that the Affordable Clean Energy (ACE) Rule put in place by the Trump administration fails to take the necessary steps to reduce greenhouse gas emissions. They argue that under the Clean Air Act, the Environmental Protection Agency (EPA) is responsible for setting limits on greenhouse gases.

The ACE Rule has much weaker regulations on national carbon emissions than the Obama administration’s Clean Power Plan. Under the ACE Rule, there is no emissions cap, individual states decide whether to lower emissions, and the rule focuses on improvements to increase efficiency at coal plants rather than transitioning to renewables or investing in carbon capture.

The new rule will decrease carbon dioxide emissions by 0.7% by 2030, according to an EPA assessment noted in a statement from New York attorney general Letitia James. The Obama-era Clean Power Plan would have reduced carbon emissions by 19%.

The new rule “is a draconian backwards step, 180 degrees in the opposite direction to where science indicates we must go.”Climate scientist Peter Kalmus at NASA’s Jet Propulsion Laboratory called the rule “obviously a protection for the fossil fuel industry” and voiced support for the lawsuit. (Kalmus did not speak on behalf of his employer.)

The ACE Rule “is a draconian, backwards step, 180 degrees in the opposite direction to where science indicates we must go,” Kalmus told Eos.

Peter de Menocal, the Dean of Science at Columbia University, also spoke in favor of the lawsuit, because aggressive emissions cuts will be needed to stay below the target warming threshold of 1.5°–2°C.

“I am hoping, praying actually, that the states prevail in their challenge of this proposed rollback,” de Menocal told Eos. “It is vitally important that we urgently and significantly accelerate emissions reductions.”

EPA Responsibility

EPA administrator Andrew Wheeler told the New York Times in June that he stands behind the new plan. “We’re on the right side of history,” he said. “It’s Congress’s role to draft statutes, not the regulatory agencies.”

Under the Clean Air Act, the EPA must use the “best system of emissions reduction” to limit greenhouse gas emissions. The EPA regulates air pollutants that risk human health, and a case heard by the Supreme Court in 2006 affirmed that carbon dioxide is included as an air pollutant.

Julie McNamara, senior energy analyst at the Union of Concerned Scientists, told Eos that limiting greenhouse gas emissions falls well within the purview of the EPA, whose mission is to protect human health and the environment. She called for the agency to take action, as human health and safety are increasingly at risk from climate change.

“It’s here, it’s happening,” McNamara said of climate change. She mentioned the recent record-breaking heat waves that swept the globe this summer.

“Right when communities across the country are reeling from the effects and its impacts are worsening and looming on the horizon,” she said, “we have our Environmental Protection Agency throwing up its hands.”

Karl R. Rábago, a professor of law at the Elisabeth Haub School of Law and executive director of the Pace Energy and Climate Center, told Eos that the lawsuit is a positive step forward.

“The administration seems bent on allowing any state to become a pollution haven,” Rábago said. “Since the current EPA won’t follow science or the law, the courts are the right next step.”

Questions on the Future of Coal

The lawsuit comes at a time when the future of coal investment is under fire. Firms in the United States have started to divest from coal projects, and there are calls for the American company AGI to rescind insurance coverage for a prominent Australian coal mine.

The ACE Rule keeps the door open for future investments of coal, which Wheeler acknowledged when the rule went into effect in June 2019.

“I don’t know who is going to invest in a new coal-fired power plant, but we’re leveling the playing field to allow that investment to occur,” said Wheeler, as reported in the New York Times.

McNamara said that future investments would be better spent replacing aging coal plants with renewables, which can be cheaper for utilities and customers alike.

“This rule would drive an investment in coal plants that are on their last legs,” she said. “That’s not building towards the future, that’s trying to hang on to a rapidly eroding past.”

Kalmus voiced concerns about human health effects of continued coal use. “There is no such thing as ‘clean coal,’” he said. “Even setting aside its climate impact, coal is by far the deadliest way to produce electricity due to its public health impact.”

Fate of Lawsuit Unclear

The ruling could have far-reaching effects on the extent that federal regulations can direct energy policy.The lawsuit, filed in the U.S. Court of Appeals in the District of Columbia Circuit, could possibly be heard before the Supreme Court. The ruling could have far-reaching effects on the extent that federal regulations can direct energy policy. The Supreme Court struck down the Clean Power Plan in 2016.

New York attorney general Letitia James (D) said in a statement that the coalition bringing the lawsuit “will fight back against this unlawful, do-nothing rule in order to protect our future from catastrophic climate change.” A group of ten public interest groups submitted a separate petition against the ACE rule on 14 August.

EPA spokesman Michael Abboud addressed the pending lawsuit in a statement reported by the Washington Post: “EPA worked diligently to ensure we produced a solid rule, that we believe will be upheld in the courts, unlike the previous Administration’s Clean Power Plan.”

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

Coastlines across the globe are already experiencing the impacts of sea level rise. Many threatened areas have begun planning for, adapting to, and mitigating the effects of current and future sea level changes—and bearing the significant associated costs. Despite the advanced stages of preparing for sea level rise in some locations, planners often lack the comprehensive sea level information needed to make fully informed decisions. This lack of information results partly from unresolved scientific problems still under investigation and in part from the difficulty of translating science into something that is useful and actionable for decision-makers.

Much of the focus was on information flows from scientists to end users, with the goal of identifying ways to streamline and improve this process.To begin addressing these challenges, 50 members of NASA’s Sea Level Change Team (N-SLCT) met last March with a diverse set of stakeholders—35 in all—representing state and local governments as part of N-SLCT’s annual science team meeting. The meeting was held in Annapolis, Md., at the Chesapeake Bay Foundation’s Philip Merrill Environmental Center. Annapolis, a U.S. coastal city, is already feeling the effects of rising seas, including dramatic increases in high-tide flooding in recent years.

The first day of the 3-day workshop featured stakeholders offering accounts of the real-world effects of sea level rise. They described the planning processes and the scientific information that are the foundation of their plans. Much of the focus was on information flows from scientists to end users, with the goal of identifying ways to streamline and improve this process.

Scientists and stakeholders also expressed interest in identifying gaps in available scientific information. N-SLCT sought answers to more specific questions as well: How is NASA science being used for coastal planning, and who is using it? How can NASA best provide useful information as these planning efforts continue?

The science team members provided updates on the significant progress in understanding the roles that ocean, ice, and land play in coastal sea level rise.These questions and the discussions that took place on the first day of the workshop were used to inform the work of N-SLCT over the remaining 2 days of the meeting. N-SLCT focuses primarily on improving understanding of present and future regional relative sea level rise. Tackling this problem requires an interdisciplinary approach, and the team’s expertise covers the broad range of factors contributing to sea level change.

The science team members provided updates on the latest scientific results, including significant progress in understanding the roles that ocean, ice, and land play in coastal sea level rise.

On the last day of the meeting, the group considered the future direction of N-SLCT. Participants identified several “team products” that will be developed over the coming months, including a set of regional sea level hindcasts and projections covering a range of timescales. They also identified the importance of further stakeholder engagement to inform future team activities; the Annapolis workshop was viewed as a first step in this direction. Further information about the meeting and team activities can be found at the N-SLCT web portal.

The research presented at this meeting was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA.

Author Information

—B. D. Hamlington (bhamling@jpl.nasa.gov), C. Boening, and H. P. Brennan, Jet Propulsion Laboratory, California Institute of Technology, Pasadena