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House Science Chair Questions Plan to Reduce Advisory Committees

Tue, 07/16/2019 - 11:14

A White House executive order that calls for eliminating one third of federal advisory committees by 30 September is coming under scrutiny by the chair of the House Committee on Science, Space, and Technology.

Committee chair Rep. Eddie Bernice Johnson (D-Texas) has called for eight science agencies to provide information by 1 August about their strategy for implementing the executive order.

“I am puzzled by the order’s apparent presumption that one third of the FACA committees established at agencies’ discretion have exhausted their usefulness.”“I am puzzled by the order’s apparent presumption that one third of the FACA committees established at agencies’ discretion have exhausted their usefulness,” Johnson wrote in 12 July letters to the heads of the Department of Energy, Environmental Protection Agency (EPA), NASA, National Oceanic and Atmospheric Administration, National Science Foundation (NSF), and other federal science agencies.

The executive order, issued on 14 June, calls for each agency to cut at least one third of its current federal advisory committees and to provide termination recommendations by 1 September regarding committees. The order states that criteria for potential termination include whether the committees’ stated objectives have been accomplished and whether operation costs for committees are considered excessive in relation to their benefits to the federal government.

The order also calls for limiting the government-wide number of federal advisory committees to 350. The order does not affect merit review panels or independent regulatory agencies, and it allows agencies to request a waiver from the order requirements.

The Federal Advisory Committee Act (FACA) database currently lists about 1,000 advisory committees throughout the federal government that provide advice to the president and the executive branch on a wide range of issues. FACA committees include NASA’s Earth science and planetary science advisory committees, EPA’s Science Advisory Board, and NSF’s Advisory Committee for Geosciences.

Johnson’s letter calls on the agencies to provide her with a list of FACA committees eligible for elimination along with information about how agencies will determine which FACA committees to eliminate, whether agencies will request waivers or mergers of committees, and whether the termination deadline is reasonable.

Her letter notes that former president Bill Clinton issued an executive order in 1993 to cut the number of advisory committees by one third, from 1,305 to 1,000. However, 4 years after that order, the U.S. Government Accountability Office found that overall costs had increased by 3%.

“While this [new] order is unlikely to reduce federal spending, it will certainly make the advisory process more opaque to the American public,” Johnson wrote.

She added that as the House Science Committee chair, “it is of utmost importance to me that science agencies continue to solicit expert advice in a manner accessible to the public. FACAs are a critical element to ensuring federal agencies operate in the best interest of the American people and an invaluable piece of the American science and technology enterprise.”

—Randy Showstack (@RandyShowstack), Staff Writer

Elephants Boost Carbon Storage in Rain Forests

Tue, 07/16/2019 - 11:13

Tropical rain forests drape over central Africa in the Congo Basin, covering an area 3 times the size of Texas. The forest is the second-largest tropical forest in the world, behind only the Amazon in South America.

African forests have taller trees and fewer tree species than other tropical forests, and researchers have long postulated that Africa’s forest elephants are responsible. Forest elephants are “ecosystem engineers” that change the type of plants that survive in the forest.

Findings indicate that 7% of carbon stores in central African rain forests will be lost if elephant populations continue to plummet.But a study in Nature Geoscience on 15 July found that African elephants do more than garden the Congo: They help the forests store more carbon in their trees. The latest findings indicate that 7% of carbon stores in central African rain forests will be lost if elephant populations continue to plummet because of poaching for ivory and shrinking habitats.

Trees suck up carbon dioxide when they photosynthesize, and they repurpose the carbon into their trunks, branches, and roots. Certain trees have higher carbon densities, especially trees that are hardwood and slow growing. Elephants encourage the growth of slow-growing trees by clomping through the forest and eating, squishing, and knocking over fast-growing softwood trees, which they find more palatable.

Researchers in the latest study created a computer model to assess the influence of elephants on vegetation in an undisturbed forest. The model mimicked elephants’ impact by giving smaller trees in the model a lower survival rate. After 250 years of elephant intervention, the forest trees were taller and wider and held more carbon above ground than before. The results agreed with field data from forest study sites.

According to the model, elephants boost the forest’s carbon-carrying capacity by 3 billion tons of carbon. France emits a similar amount of carbon through fossil fuel emissions over the course of 27 years, lead author Fabio Berzaghi told Eos.

As countries release more carbon dioxide into the atmosphere, governments are looking for cost-effective ways to sequester carbon. Yet as poaching reduces elephant populations, which have fallen 90% over the past century, the study’s findings indicate that the amount of carbon stored in the African forest will drop as well. Berzaghi said there’s no way to know how much has already been lost.

Berzaghi noted that countries are missing out on a natural way to keep carbon stored in the ground. “Carbon technologies, at the moment, are really expensive,” Berzaghi said. “Nature offers a lot of these services for free.”

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

An Integrated History of the Australian-Antarctic Basin

Mon, 07/15/2019 - 11:21

Understanding the nature of sedimentary rock deposits in the Australian-Antarctic Basin is crucial for learning how oceanographic conditions evolved as Earth transitioned from a warm and humid Late Cretaceous “greenhouse” to a cool and dry Cenozoic “icehouse” world. Yet unraveling the tectonic, climatic, and oceanographic history of this basin, which began rifting in the Middle to Late Jurassic roughly 165 million years ago, has been challenging because of a paucity of data as well as varying interpretations of each margin.

Now Sauermilch et al. have, for the first time, collated all available data to construct a unified seismostratigraphic framework for the Australian-Antarctic Basin. The team’s extensive data set includes more than 500 seismic reflection lines collected across the region, some of which have only recently become available through the Scientific Committee on Antarctic Research, as well as newly obtained data about marine sedimentary rocks from offshore drilling efforts.

The compilation indicates that prior to the start of Antarctic glaciation about 34 million years ago, both margins of the basin experienced similar patterns of sedimentation and thus share three key sedimentary units that are similar in both thickness and structure. They include a unit deposited between the Late Cretaceous and mid-Paleocene (about 94 million to 58 million years ago), when sedimentation along both margins was dominated by large river systems that formed offshore delta deposits up to 5 kilometers thick in the still-narrow ocean basin.

Later in the sedimentary record, the presence of drift deposits along both continental rises indicates that by about 58 million years ago in the late Paleocene, ocean bottom currents had begun circulating clockwise within the widening basin. The authors suggest that these currents then grew stronger and progressed eastward through the Eocene (56 million to 34 million years ago) while at the same time global cooling and increasing aridity led to a large reduction in the amount of sediment shed from both continents. These conditions ultimately led to a dearth of sediment deposition in the basin during the middle to late Eocene, as demonstrated by two large-scale hiatuses found in International Ocean Discovery Program cores from the Antarctic continental slope.

The integrated seismostratigraphic model developed in this study offers new insights into the history of the Australian-Antarctic Basin, providing new constraints on landscape evolution and ocean circulation that should be incorporated into future paleoceanographic models of the basin.  (Journal of Geophysical Research: Solid Earth, https://doi.org/10.1029/2018JB016683, 2019)

—Terri Cook, Freelance Writer

Teams Invited to Test Coastal Hyperspectral Imaging Algorithms

Mon, 07/15/2019 - 11:21

Satellite remote sensing using a few discrete wave bands of light, selected to fit the specific application (multispectral imaging), is a well-established means of monitoring the world’s open oceans. Coastal and inland waters are often much more complex, and the methods used to study these waters are more complex as well. These waters have greater sediment and algal loads than the open oceans, and light can reflect off the bottoms of these shallower water bodies, which complicates data analysis.

Remote sensing of coastal and inland environments requires hyperspectral imaging—simultaneously measuring tens to hundreds of narrow, contiguous wave bands (typically visible through near infrared)—to disentangle multiple confounding signals. Efficient manipulation of large hyperspectral image data volumes, as well as subsequent generation of meaningful and accurate data products, requires sophisticated algorithms, which continue to evolve and improve.

In May 2018, participants in the Hyperspectral Imaging of Coastal Waters workshop, sponsored by the Alliance for Coastal Technologies (ACT) and the National Oceanic and Atmospheric Administration (NOAA), recommended a technology demonstration of hyperspectral remote sensing algorithms applied to coastal and inland waters. In May 2019, ACT followed up with an introductory webinar to plan the demonstration.

Thirty-seven individuals participated in the webinar, representing academic and government research institutions, as well as technology developers from around the globe. There were representatives from ACT, seven members of a technical advisory committee established for this demonstration, four individuals and teams already registered to participate in the demonstration, and seven prospective individuals and teams.

NOAA established ACT in 2001 to bring about fundamental changes in environmental technology innovation and research and in operations practices. ACT achieves its goal through specific technology transition efforts involving both emerging and commercial technologies. Its efforts include the explicit involvement of resource managers, small- and medium-sized firms, world-class marine science institutions, NOAA, and other federal agencies. ACT’s core efforts are as follows:

technology evaluations for independent verification and validation of technologies technology workshops and webinars for capacity and consensus building and networking technology information clearinghouses, including an online technologies database

The goal of the hyperspectral technology demonstration is to evaluate the capabilities and maturities of various algorithms.For the hyperspectral technology demonstration, ACT is inviting individuals and teams with established processing routines and algorithms to work with highly described hyperspectral data sets and corresponding in situ validation data sets. The goal of the demonstration is to evaluate the capabilities and maturities of various algorithms. This exercise is not a research project; rather, it is an opportunity to enhance communication within the community and to advance future applications of hyperspectral remote sensing in coastal waters.

Three views of the Torres Strait, between Australia and Papua New Guinea, from the CORAL mission illustrate an example of applied hyperspectral data: pseudotrue color image of 12 flightlines were acquired by the Portable Remote Imaging Spectrometer (PRISM) on 12 October 2016 (left); the results of CORAL data processing estimate the probabilities that image pixels are dominated by coral, algae, or sand (middle); and a map of the percentages of coral-dominated pixels in 1 × 1 kilometer grid cells, which enables researchers to fulfill CORAL’s science objective of investigating reef condition in relation to large-scale biogeophysical forcings (right). PRISM data collected for CORAL are freely downloadable.

Data sets being used in the hyperspectral algorithm technology demonstration characterize kelp forests, coral reefs, harmful algal blooms (including those in inland waters), sea grass, and water quality. It is not required that all individuals and teams work with all data sets. Individuals and teams will select the data sets they are most familiar with, and they are welcome to work with more than one data set or contribute additional data sets that will be made available to all demonstration participants.

The resulting data products are useful to scientists developing a greater understanding of these natural systems, as well as to resource managers tasked with conservation and decision-making. The data products also support future hyperspectral missions such as NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) and Surface Biology and Geology (SBG).The deadline for individuals and teams to register to participate in the technology demonstration is 31 August 2019.

The hyperspectral algorithm technology demonstration will be conducted over a 4- to 6-month time frame. The original request for technology was released 20 March 2019. The deadline for individuals and teams to register to participate is 31 August 2019.

ACT anticipates an additional webinar or in-person workshop in fall 2019. Technology demonstration results will then be shared in a final workshop at the University of Hawai‘i at Mānoa in winter 2020. The overarching goal of the demonstration includes publishing individual project results and synthesis papers on learned best practices. Several manuscripts and a final report are expected to result from these collaborations.

ACT continues to accept applications to participate in the demonstration. Please contact Thomas Johengen with expressions of interest. ACT will pay for travel costs for one to two members of each team to attend workshops.

—Margaret A. McManus (mamc@hawaii.edu), University of Hawai‘i at Mānoa; and Eric Hochberg, Bermuda Institute of Ocean Sciences, St. George’s

Places to Celebrate Apollo 11’s Fiftieth Anniversary

Mon, 07/15/2019 - 11:19

Big cities and small towns alike are gathering this week to celebrate the 50th anniversary of the Apollo 11 mission. Celebrations last all week, and most culminate on Saturday on the anniversary of the first crewed landing on the Moon.

Places with direct ties to the mission are pulling out all the stops. Kennedy Space Center in Florida is hosting events that celebrate its role in every step of the mission, from launch to splashdown. Space Center Houston in Texas restored the Apollo 11 mission control center to its 1969 state. In Washington, D.C., the Smithsonian National Air and Space Museum is turning the Washington Monument into Apollo 11’s Saturn V rocket.

Apollo 11’s Saturn V rocket was launched on 16 July 1969. Credit: NASA

If you live in the United States, chances are high that there’s an anniversary event somewhere near you this week or beyond. We can’t list them all, but here are six that you don’t want to miss.

Across the Country: A new documentary brings viewers into the drama of the Apollo 11 mission as it unfolded in 1969. The documentary, Apollo 11, was crafted entirely from archival video and audio, including a cache of recently discovered 65-millimeter film from the mission’s launch and recovery, as well as hours of uncataloged audio from the mission control center.

The film gives personal glimpses into mission figures like Neil Armstrong, Edwin “Buzz” Aldrin, and Michael Collins. The newly restored audio tracks recorded the voices of 60 key personnel in Houston’s control center and shine new light on minute-by-minute mission activities. Despite knowing how it ends, audiences widely agree that Apollo 11 beautifully re-creates the tension and excitement felt by the mission’s staff and its eager spectators.

The documentary is currently playing on IMAX screens around the United States and is also available for purchase in a variety of formats.

Wapakoneta, Ohio: Neil Armstrong’s birthplace is hosting a Summer Moon Festival from 19 to 21 July at the Armstrong Air and Space Museum. The festival follows a week of Apollo-related events and will include Moon runs, concerts, science presentations, lunar rover demonstrations, and visits from NASA astronauts.

Arecibo, Puerto Rico: The largest radio telescope in the United States invites the public to look up at and learn about the Moon on Saturday. In addition to observing the night sky through (visible light) telescopes, the evening event will also include educational talks, astronomy activities, and a film screening.

Chicago, Ill.: Adler Planetarium is inviting people to a discussion on 19 July about Moon exploration. The forum, “Why Go to the Moon? A Conversation on the Past and Future of Lunar Exploration,” will include a space historian and a historian of colonialism and invites the public to share questions and thoughts about why we should (or shouldn’t) go back to the Moon.

New York, N.Y.: Apollo’s Muse: The Moon in the Age of Photography brings science and art together in a showcase of visual depictions of the Moon. The exhibit, at The Met Fifth Avenue through 22 September, includes photographs, drawings, paintings, and films that highlight humanity’s persistent fascination with our celestial neighbor.

Fort Worth, Texas: The Fort Worth Museum of Science and History’s Launchpad: Apollo 11 Promises Kept tells the story of human spaceflight past, present, and future. The gallery, open through the end of the year, features Apollo artifacts, science art, and a look at the face of modern spaceflight. One special feature is a virtual reality experience that lets visitors see what the astronauts saw as they walked on the Moon.

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

Podcast: Apollo Moon Rocks

Mon, 07/15/2019 - 11:18

Ryan Zeigler has a one-of-a-kind job: He’s the guy in charge of the Moon rocks.

Ryan Zeigler is NASA’s Apollo sample curator. Credit: Ryan Zeigler

Starting with Apollo 11 in 1969 and ending with Apollo 17 in 1972, astronauts brought back more than 380 kilograms of samples from the Moon—from micrometer-scale motes of dust to boulders weighing more than 13 kilograms. In the 50 years since the Moon rocks arrived back on Earth, scientists all over the world have used these samples to peer back in time to the early days of our solar system, making major discoveries about the formation of the Moon and Earth.

Today, the Moon rocks are safely stored in a windowless, hurricane-proof building at Johnson Space Center. It is Zeigler’s job to oversee the samples and review proposals from scientists who wish to study them. Earlier this year, NASA announced that they will open up a new cache of never-before-studied Apollo samples, which they hope will reveal even more insights about our nearest neighbor and our own planet.

In addition to the planetary science discoveries the Apollo samples have yielded, the Moon rocks have also taught scientists how to safely handle, store, and study samples from other planetary bodies, including asteroids sampled as part of the Hayabusa and Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) missions.

Moon rocks are stored at the hurricane-proof Lunar Sample Laboratory Facility and sample vault at Johnson Space Center. Credit: NASA

In this Centennial episode of Third Pod from the Sun, Zeigler provides an insider’s view of his unique career—a job that is equal parts exciting, humbling, and nerve-racking. He details how astronauts obtained samples from the Moon, how the Apollo samples are stored and provided to researchers, the discoveries the rocks have yielded over the past 50 years, and what it is really like to hold a Moon rock in your hand.

This episode was produced by Nanci Bompey and mixed by Collin Warren.

—Nanci Bompey (@nbompey), Contributing Writer, AGU

Seismic Sensors Probe Lipari’s Underground Plumbing

Mon, 07/15/2019 - 11:16

Just north of the island of Sicily, near the toe of Italy’s “boot,” a chain of volcanic islands traces a delicate arc in the Mediterranean Sea. This chain, the Aeolian Islands, hosts popular tourist resorts in proximity to some of Earth’s most active and well-known volcanoes, including Etna and Stromboli. Lipari, the largest of these islands, lies just north of the island of Vulcano, for which these eruptive features are named. Lipari is less well characterized than some of the other nearby volcanoes, but one research group is setting out to change this.

This is the first time that a dense seismic array has been deployed to investigate a hydrothermal system in the volcanically active Aeolian Islands.Lipari is located ~80 kilometers north of the well-monitored Etna volcano. The island’s hydrothermal system, in which magma heats the water underground, is not connected to eruptive centers, but, rather, is connected to the regional fault system that delimits the western boundary of the active Ionian subduction zone.

Lipari holds a unique place in our understanding of the tectonic evolution and hydrothermal activity of volcanoes emplaced in subduction zones. Within the framework of the ring-shaped Aeolian arc, the unexpected NNW–SSE alignment of Lipari and Vulcano has been related to a major regional discontinuity, the Tindari-Letojanni subduction transform edge propagator (STEP) fault, a tear in a tectonic plate that allows one part of the plate to plunge downward while an adjacent part remains on the surface (Figure 1).

Fig. 1. These tectonic and bathymetric maps show (a) southern Italy and (b) the Aeolian Islands. The bathymetric data are from Ryan et al. [2009]. Major faults are shown as black lines. Regional earthquakes larger than magnitude 3 (black dots) were recorded over the past 3 decades by the permanent Italian seismic network (magenta triangles). Events larger than M 3 that occurred in the time window of the current experiment are shown as cyan stars. The yellow star off the northeastern coast of Sicily shows the location of the 1 November 2018 ML 3.2 earthquake whose waveforms are shown in the left-hand plot of Figure 3. In Figure 1a, blue dashed lines in the Tyrrhenian Sea indicate the isodepths (50, 100, 200, and 300 kilometers) of the slab [Barreca et al., 2014]. Shown in Figure 1b are the locations of Lipari, the Sisifo-Alicudi fault (SAf), and the Tindari-Letojanni STEP fault (STEP-TLf). Click image for larger version.One innovative way to monitor the deep and shallow dynamics of magmatic systems is to deploy dense arrays of seismic sensors over active volcanoes [Hansen and Schmandt, 2015; Ward and Lin, 2017; Farrell et al., 2018]. Thus, to understand Lipari’s unusual setting, we deployed a dense array comprising 48 wireless, self-contained seismic instruments. This is the first time that a dense seismic array has been deployed to investigate a hydrothermal system in the volcanically active Aeolian Islands and the volcanism in the proximity of a STEP fault.

Transporting the seismic sensors, called nodes, to Lipari required a transatlantic shipment from Louisiana State University (LSU) to Istituto Nazionale di Geofisica e Vulcanologia (INGV) in Rome, followed by a ferry trip to Lipari. Over the course of 2 days, two crews of two people each placed 48 instruments, spaced ~0.1–1.5 kilometers apart, in a wide variety of locales: with homeowners and hotel owners, at the Lipari observatory, on the sides of streets, and buried in the near surface beneath a few centimeters of soil (Figure 2).

Fig. 2. Three-dimensional perspective view of a Google Earth map of Lipari Island, which covers an area of about 35 square kilometers. The last eruption on this island was in 1220 CE at Monte Pilato. The locations of the ZLand three-component seismic nodes are shown as yellow triangles. A magenta triangle indicates broadband station ILLI of the Italian permanent seismic network. Site photos taken at selected locations are also shown. The inset shows a detailed map of the hydrothermal area (modified from Cucci et al. [2017]) and the locations of photos A, B, and C, which characterize the hydrothermal alteration.Researchers from INGV in Rome, the Department of Geology and Geophysics at LSU, and the Seismological Laboratory of the California Institute of Technology deployed the 48 FairfieldNodal ZLand three-component nodes, which have a 5-hertz corner frequency. The nodes recorded one data point every 4 milliseconds from 16 October to 14 November 2018.

After their transatlantic voyage from Louisiana to Rome, seismic sensors await a ferry trip to Lipari. Credit: A. Esposito Lipari’s Tectonic Neighborhood

Lipari Island belongs to the Aeolian archipelago, a group of subaerial and submarine volcanoes located in southern Italy between the southern Tyrrhenian Sea back-arc basin and the Calabrian Arc, an orogenic belt affected by late Quaternary extensional tectonics. The NNW–SSE Lipari-Vulcano alignment (Figure 1) coincides with the regional tectonic boundary of the Ionian Sea–Calabrian Arc subduction system that is marked by the Tindari-Letojanni STEP fault [Barreca et al., 2014].

To the west of the archipelago, the WNW–ESE oriented Sisifo-Alicudi fault accommodates shortening related to the eastern termination of the contractional belt (Figure 1). The Tindari-Letojanni and Sisifo-Alicudi fault systems are characterized by shallow seismicity, at depths of less than 25 kilometers, and recorded earthquakes of M 5.8 or less, including the M 4.7 Ferruzzano earthquake in 1978 [Gasparini et al., 1982].

The Aeolian volcanoes, emplaced on 15- to 20-kilometer-thick continental crust, are the most recent evidence of the magmatism that started during the Pliocene epoch (5.3–2.6 million years ago). This magmatism started in the central sectors of the Tyrrhenian Sea and migrated southeastward toward the Calabrian Arc.

From about 1 million years ago to the present time, the volcanoes have been producing magma with calc-alkaline, shoshonitic, and alkaline potassic compositions [De Astis et al., 2003; Barreca et al., 2014]. The geochemical affinity of these rocks and the deep seismicity (reaching depths of 550 kilometers) in the southern Tyrrhenian Sea indicate that the Aeolian Islands represent a volcanic arc related to the subduction and rollback of the Ionian slab beneath the Calabrian Arc [Milano et al., 1994; De Astis et al., 2003].

Early volcanic activity at Lipari ejected lava and rocks into the air, but today, geothermally heated water is more common. Credit: L. Cucci

Early volcanic activity on Lipari (150,000 years ago and earlier) was concentrated in the western part of the island and focused along north–south aligned vents. Later on, between 119,000 and 81,000 years ago, the Sant’Angelo and Monte Chirica volcanoes deposited lava and pyroclastics (volcanic material that is forcibly ejected into the air) in the central sector of the island (Figure 2).

Hydrothermalism on Lipari is not associated with centers of recent volcanic activity, and fluid pathways are strictly controlled by faults and fractures.From 42,000 years ago to 1220 CE, the activity was concentrated in the southern and northern sectors. This activity included pyroclastics related to subplinian eruptions, domes, and lava flows. Currently, hydrothermal activity (the expulsion of geothermally heated water) characterizes Lipari, Vulcano, and areas offshore of Panarea and Salina. The Lipari hydrothermal field (approximately 0.5 × 0.15 kilometer; see inset in Figure 2) is located along a north–south striking alteration belt in the western and older sector of the island and is characterized by gypsum-filled veins, normal faults with a prevailing NNW–SSE to north–south strike, and active fumaroles.

Hydrothermalism on Lipari is not associated with centers of recent volcanic activity (less than 40,000 years old), and fluid pathways are strictly controlled by faults and fractures [Cucci et al., 2017]. Vein networks of gypsum (a type of sulfur mineral) affect the hydrothermal system in the lavas and scorias of the oldest Timponi volcanoes, the overlying pyroclastics of Monte Sant’Angelo, the 27,000-year-old Pianoconte pyroclastic deposits, and the present-day soil (inset in Figure 2). The hydrothermal alteration process has been going on for less than 27,000 years and is still active [Cucci et al., 2017].

A Mountain of Data Fig. 3. Seismograms from two earthquakes at local (left) and regional (right) distances recorded at the Lipari array. Vertical components of the ground velocity are low-pass filtered at 5 and 2 hertz for the ML 3.2 and MW 6.8 magnitude events, respectively, to improve the signal-to-noise ratio. Waveforms at the bottom of each plot are the seismograms of the two events recorded by the permanent broadband seismic station ILLI located on the southern tip of Lipari, as shown in Figure 1b, with numbers in bottom left corners indicating the epicentral distances. Click image for larger version.

We collected more than 300 gigabytes of data, which include local, regional, and teleseismic (distant) earthquakes as well as ambient noise and volcanic tremor data. During the period of the experiment, about 50 earthquakes occurred within 100 kilometers of Lipari. Half of these had magnitudes of less than 2, but we also recorded 18 events larger than M 5 that occurred in the region and farther away. In Figure 3, we show two examples of recorded seismic waveforms from an ML 3.2 local earthquake and an Mw 6.8 regional earthquake.

We aim to investigate in detail the crust and upper mantle beneath Lipari Island using receiver functions to characterize Earth’s structural response near the instrument and regional tomography to construct a three-dimensional image of Earth’s nearby interior. We will also analyze ambient noise and local volcanic tremors.

We plan to merge the seismic data set with other observables such as geochemical measurements and structural data to get a more robust and complete picture of the tectonic setting. We will apply modern and sophisticated processing and analysis techniques used in seismological studies to the nodal seismic array data.

The deployment of nodal arrays fills a unique niche in monitoring active volcanoes. In comparison to traditional portable seismic stations, nodal arrays enable a high-quality data set to be obtained over a short deployment period, at lower costs, with easier site selection capabilities, and with easy and quick installation procedures.

Our collaborative field experiment is the latest vehicle for learning about the seismic structure of Lipari and an excellent approach to linking the unrest at depth to volcanic and hydrothermal activity at the surface in similar settings. This project will contribute to the evaluation of the geohazards of the Mediterranean region, where the African and Eurasian plates converge.


We thank Comune di Lipari for hosting the experiment and INGV Catania and Lipari Observatory (L. Pruiti) for the logistical support. We are grateful to R. Vilardo and M. Martinelli of the Polo Museale di Lipari, Regione Sicilia; the Hotel Antea; Co.Mark and Tenuta Castellaro; and Alessandro (a grocery store) in Acquacalda for hosting some nodes of the experiment. We thank INGV Roma 1 for funding and supporting the project and the Department of Geology and Geophysics at LSU for supporting this project. A.E. was funded by INGV Osservatorio Nazionale Terremoti (ONT). LSU students R. Ajala and E. McCullison assisted with the deployment setup and preparation of the nodes. Data will be available in November 2020 (2 years after the last instrument was retrieved from the field) by contacting the corresponding author.

AGU Awarded Grant from the Alfred P. Sloan Foundation

Fri, 07/12/2019 - 15:58

AGU has been awarded a 3-year grant from the Alfred P. Sloan Foundation to launch the AGU Ethics and Equity Initiative: Catalyzing Cultural Change in the Sciences with New Resources and Tracking Tools. This initiative is designed to directly address sexual harassment and other related matters that affect gender discrimination through new educational resources and validated measurement tools. The initiative is being developed through an AGU partnership with the National Center for Professional & Research Ethics (NCPRE) at the University of Illinois. The new resources in this project are designed to allow for broad adaptation by the science community.

Addressing an Urgent Issue in STEM

The initiative uses “a data-driven, ready to use approach that the science community needs.”“Multiple national studies have identified persistent sexual harassment and harassment-related issues in STEM (science, technology, engineering, and mathematics) that have driven talent from these fields. These issues have been ignored for decades; institutions, societies, and individuals are looking for solutions,” said AGU CEO/executive director Chris McEntee. “This grant from the Sloan Foundation helps AGU build on recommendations from the 2018 National Academies of Sciences report on Sexual Harassment of Women: Climate, Culture, and Consequences in Academic Sciences, Engineering, and Medicine and will help address an urgent problem using a data-driven, ready to use approach that the science community needs.”

Focusing on development, implementation, and broad adoption, the initiative will do the following:

It will create a series of annual, unique, and in-person workshops and leadership development offerings related to advancing antiharassment and related ethics and equity in science to reach more than 500 scientists. It will also develop a validated, integrated, and easy to use work climate assessment tool that allows for direct benchmarking and analysis, targeting broad promotion and adoption by academic and scientific institutions. The work to be performed under this initiative will include a comparative dimension and lead to new understandings and interventions to address the identified problems.

The project will be guided by a 12-person, multidisciplinary advisory board that includes representatives from across scientific organizations and institutions.

AGU Positioned to Lead

“AGU is positioned to lead the effort across the sciences to help ensure that these issues are proactively addressed and that the scientific community is open and welcoming to all.”“Harassment in science has been a particular concern for scientific disciplines requiring field research. AGU is positioned to lead the effort across the sciences to help ensure that these issues are proactively addressed and that the scientific community is open and welcoming to all,” said AGU president Robin Bell. “The grant from the Sloan Foundation will help us ensure Earth and space sciences continues to lead the sciences by helping our community with data, tools, and innovative approaches to attract and retain everyone keen to engage in science.”

In September 2017, AGU was the first scientific society to adopt a revised Ethics Policy that included harassment as a form of research misconduct. This policy was expanded to include AGU members, staff, volunteers, and nonmembers participating in AGU-sponsored programs and activities, including AGU honors and awards and governance. This new initiative also builds on AGU’s recent work to help establish the Societies Consortium on Sexual Harassment in STEMM. Now with more than 110 member societies, the consortium is charged with further developing and sharing leading practices that drive cultural change and advance workplace excellence in science, technology, engineering, mathematics, and medical fields.“An environment that supports research integrity must support the fullest creativity and productivity of all participants in the research enterprise.”

A Joint Effort with NCPRE

“AGU and NCPRE have strong records of actions, results, innovation, and partnerships in leading change on these issues across the scientific community. NCPRE is excited to partner with AGU to extend our existing tools and our belief that an environment that supports research integrity must support the fullest creativity and productivity of all participants in the research enterprise,” said C. K. Gunsalus, NCPRE director.

The Alfred P. Sloan Foundation selects grantees that “have a high expected return to society, exhibit a high degree of methodological rigor, and for which funding from the private sector, government, or other foundations is not yet widely available.”


Founded in 1919, AGU is a not-for-profit scientific society dedicated to advancing Earth and space science for the benefit of humanity. We support 60,000 members, who reside in 135 countries, as well as our broader community, through high-quality scholarly publications, dynamic meetings, our dedication to science policy and science communications, and our commitment to building a diverse and inclusive workforce, as well as many other innovative programs. AGU is home to the award-winning news publication Eos, the Thriving Earth Exchange, where scientists and community leaders work together to tackle local issues, and a headquarters building that represents Washington, D.C.’s first net zero energy commercial renovation. We are celebrating our Centennial in 2019. #AGU100

The National Center for Professional & Research Ethics (NCPRE) creates and shares resources to support the development of better ethics and leadership practices. It focuses on leadership in a variety of institutional settings, from academia to business. NCPRE is part of the Coordinated Science Laboratory in the College of Engineering at the University of Illinois at Urbana-Champaign.

The Alfred P. Sloan Foundation is a philanthropic, not-for-profit grant-making institution based in New York City. Established in 1934 by Alfred Pritchard Sloan Jr., then president and chief executive officer of the General Motors Corporation, the foundation makes grants in three broad areas: direct support of research in science, technology, engineering, mathematics, and economics; initiatives to increase the quality and diversity of scientific institutions; and efforts to enhance and deepen public engagement with science and scientists.

A More Accurate Global River Map

Fri, 07/12/2019 - 13:56

Mapping all of the world’s rivers, creeks, and streams is a daunting task, particularly in places like the Arctic, where accurate topographic data are hard to obtain. Scientists now have created a new map of global rivers based on a largely automated computer algorithm that can accurately predict where rivers flow—a tool that could help project future flooding as Earth’s climate changes.

Many different factors affect the flow of water over land, including terrain steepness, watershed size, and human-built structures like canals. Scientists have previously used topographic data collected by spacecraft such as NASA’s Shuttle Radar Topography Mission to generate detailed, 3-D models of Earth’s surface, but these maps sometimes distort the slope of local terrain due to observation errors.

In the new study, Yamazaki et al. used an updated version of a popular topographic data set called the Multi-Error-Removed Improved-Terrain Digital Elevation Model (MERIT DEM), which was published in 2017 by members of the same team, to develop a computer algorithm that predicts where rivers flow with very little human guidance. The new, publicly available hydrographic data set, called MERIT Hydro, reveals rivers at high resolution in approximately 90- × 90-meter gridded pixels, includes the Arctic region, and is less prone to errors caused by tree canopies or inaccurate elevation than existing global hydrographic maps, the authors write. Compared with existing maps, the synthetic hydrographic maps made remarkably accurate predictions of where rivers, such as China’s Pearl River and the Ob River in Russia, should be, the team reported.

To further refine the map, the team also included global Landsat data, as well as data from the crowdsourced mapping database OpenStreetMap, which the researchers searched using tags such as “waterway,” “river,” “stream,” “brook,” and “wadi.” On the basis of this combined data set, the algorithm integrated information on small streams not captured by current satellite images. The OpenStreetMap data also allowed the researchers to generate maps of human-made stream networks, like irrigation canals, that could be flood prone.

A remaining challenge for more accurate river mapping is in arid regions such as the Danakil Desert in Ethiopia, where streams are often intermittent and ephemeral, the researchers noted.

The team writes that it hopes other scientists will build upon and improve the free, open-source MERIT Hydro program, noting that it could be used in predicting flood risks and analyzing ecosystem biodiversity and carbon emissions. (Water Resources Research, https://doi.org/10.1029/2019WR024873, 2019)

—Emily Underwood, Freelance Writer

Unlocking a Treasure Trove for Subsurface Characterization

Fri, 07/12/2019 - 13:55

It’s difficult to know the exact characteristics of what’s immediately beneath the ground since it’s out of sight and largely inaccessible. A recent article in Reviews of Geophysics describes a new type of analysis that measures the response of groundwater to Earth and atmospheric tides and uses that to infer hydrogeological properties of the subsurface. Here, some of the authors describe developments in this field and their potential applications.

What are Earth and atmospheric tides and how do they affect groundwater?

Ocean tides, which are primarily caused by the gravitational pull of the Moon and Sun, are not the only naturally occurring tides on planet Earth. The same celestial movements cause “Earth tides”, which are the shifting of the Earth’s solid surface, and “atmospheric tides”, which are daily oscillations in the troposphere and stratosphere.

Groundwater in the subsurface is affected by these Earth and atmospheric tides, causing changes in groundwater level, albeit on a much smaller scale than the daily rise and fall of sea level. This is because groundwater is required to move through sediments or rock to follow the tides, rather than slosh backwards and forwards freely like water in the ocean.

Representation of groundwater pressure head measured in a well penetrating a semiconfined aquifer with a relatively rigid matrix subjected to (A) strains caused by Earth tides (using the moon as an example celestial body) and (B) barometric loading caused by atmospheric tides. Credit: McMillan et al. [2019], Figure 1What can the groundwater’s response to Earth and atmospheric tides tell us about what lies underground?

The extent to which the groundwater level changes in response to tidal forces and the time it takes to do so depends on the hydrogeological properties of subsurface materials in any given locality. These include characteristics such as porosity (pore space or volume of water a unit of material can hold), permeability (ability to transport water), storage coefficient (amount of water it can release), and specific storage or specific yield (amount of water that can be released per unit volume).

Thus, we can measure tidal changes and groundwater levels and use the relationships to understand subsurface hydrogeological characteristics. This is called Tidal Subsurface Analysis.

Conceptual overview of the pressure influences of tidal forces down through a subsurface profile in time and frequency domains. (a) and (b) are atmospheric pressure, (c) and (d) are the unconfined groundwater responses, (e) to (h) are confined groundwater responses. Credit: McMillan et al. [2019], Figure 14What benefits does this kind of analysis offer over other ways to understand the subsurface?

Standard hydrogeological techniques for understanding the subsurface (such as pump tests) require measurements that are intrusive (large pumping bores), require specific infrastructure (pumps and generators) and are expensive to conduct (staff time).

The advantage of measuring the groundwater response to Earth and atmospheric tides is that only passive water level or pressure monitoring and smart analysis is needed to quantify physical properties.

This opens up the opportunity for analysis at many more locations and at a lower cost.This opens up the opportunity for such analysis to occur at many more locations and also allows us to capture a much more refined picture of the subsurface properties, at a lower cost. It could also enable the tracking of changes in these properties over time as water level monitoring can be done continuously at little expense.

Why are these methods only emerging now?

Separate methods for barometric or earth tide analysis have been available for quite some time as they were pioneered by the United States Geological Survey in the 1960s. However, we believe that they have not been pursued because of the belief that gravity or strain measurements are required in addition to groundwater levels.

Our work has demonstrated two major advances: first, we can use precisely computed Earth tide records instead of expensive gravity measurements; and second, we can now disentangle the influence of Earth and atmospheric tides on groundwater systems, something that has made analysis very difficult in the past.

The prevalence of more multidisciplinary skilled teams has advanced these methods.Tidal Subsurface Analysis requires knowledge of subsurface poroelasticity. This is standard knowledge in petroleum engineering but not yet among hydrogeologists. The prevalence of more multidisciplinary skilled teams and non-specialist access to computer codes have dramatically increased the accessibility and applicability to advance such methods.

What are some of the applications of Tidal Subsurface Analysis?

Groundwater is the world’s largest freshwater resource and forms the primary water source for billions of people. However, this vital resource is rapidly being depleted, often poorly monitored or quantified, and inadequately managed.

Tidal Subsurface Analysis increases our knowledge of the subsurface and the groundwater resource in both time and space.Tidal Subsurface Analysis increases our knowledge of the subsurface and the groundwater resource in both time and space.

Thus, we can better predict what will happen when water is extracted from the subsurface and use this knowledge to improve the management of precious groundwater resources.

What are some of the unresolved questions where additional research, data or modeling is needed?

Overview of the suggested workflow for quantifying subsurface properties using the groundwater response to Earth and atmospheric tides. Credit: McMillan et al. [2019], Figure 15Only a limited number of studies have compared the hydrogeological properties obtained from Tidal Subsurface Analysis with those from traditional investigation techniques, which means that there is limited verification of the method so far.

There is a currently some uncertainty about the area of influence that is being monitored, i.e. are the calculated properties representative of the subsurface at the point of monitoring or for several to tens of meters away from the monitoring point.

In other words, we don’t know how large a volume or area of the subsurface the calculated properties represent. This could be tested using numerical models which, to the best of our knowledge, do not currently exist.

There is, therefore, a big opportunity for further numerical and experimental research to validate and verify the results for a variety of subsurface conditions. This would increase confidence in the accuracy and reliability of Tidal Subsurface Analysis and help establish it as a leading practice technique.

—Timothy McMillan (email: t.mcmillan@unsw.edu.au), University of New South Wales, Australia; Gabriel Rau, Karlsruhe Institute of Technology, Germany

Zombie Worms, Ploonets, and Other Things We’re Reading This Week

Fri, 07/12/2019 - 13:54

Ancient Life Awakens Amid Thawing Ice Caps and Permafrost: “This Twitter thread was a really good breakdown of the science behind that splashy ‘40,000-year-old frozen worms’ headline. Also a good reminder to read more than just headlines when it comes to science news.” —Kimberly Cartier, Staff Writer

Okay, so: I was understandably incredulous to read this. 41,000 years is unheard of in terms of an organism surviving deep freeze, by orders of magnitude. So, I went to the source. https://t.co/7dD4FwnNSF

— Dr. Jacquelyn Gill (@JacquelynGill) July 10, 2019

. Moons That Escape Their Planets Could Become “Ploonets”: “Hard not to smile when repeatedly reading the words “ploonet” and “ploonethood.” Quirky story about an as yet theoretical but entirely likely type of celestial object.” —Timothy Oleson, Science Editor . The California Coast Is Disappearing Under the Rising Sea. Our Choices Are Grim: “This article is a tour de force of sea level rise woes in California. I couldn’t stop reading.” —Jenessa Duncombe, Staff Writer . Many Water Cycle Diagrams Promote Misconceptions: “I felt silly for not having noticed this before, but hindsight is 20/20. Where are the people?” —Kimberly Cartier, Staff Writer . A New Plan for Keeping NASA’s Oldest Explorers Going: “To infinity and beyond. NASA engineers work to extend lives of interstellar probes.” —Randy Showstack, Staff Writer . Chinese Air Pollution Dimmed Sunlight Enough to Impact Solar Panels: “In China, coal has literally been throwing shade at solar power generation for decades.” —Timothy Oleson, Science Editor . Get to Know the National Science Foundation’s DKI Solar Telescope: “The Daniel K. Inouye Solar Telescope’s deformable mirror can correct distortions in Earth’s atmosphere to as small as the width of 40 hydrogen atoms.” —Caryl-Sue, Managing Editor

The Mystery of the Moon’s Missing Metals

Fri, 07/12/2019 - 13:53

The Moon’s missing precious metals may never have arrived in the first place.

Colliding asteroids delivered metals such as gold and iridium to both Earth and the Moon early in the solar system’s history, with Earth collecting more than its smaller satellite. But samples of Moon rocks collected by Apollo missions revealed that the Moon had significantly less material than could be accounted for by its size. New research now suggests that the dearth may be caused in part by the Moon’s inability to hold on to some of these metals, with the late crystallization of the lunar mantle also playing a role.

The early solar system was a violent place, with material left over from planet formation crashing into newborn worlds. One collision carved the Moon out of Earth, leaving both worlds briefly molten as their layers settled out. Precious metals, which have an affinity for iron, sank to the cores of newborn worlds, removing them from the crust and mantle. Any of these highly siderophile elements (HSEs) found in the crust today were delivered by collisions with smaller debris.

Because Earth presents a larger target than the Moon, scientists anticipated that the Moon should have roughly 20 times less HSEs at its surface. Instead, Apollo samples revealed that the satellite contains roughly 1,000 times less precious metals than Earth, suggesting that perhaps it was hit by significantly fewer objects. The discrepancy has had scientists scratching their head for the past few decades.

“We identify that a key factor for the interpretation of the HSE record is the impactor retention rate—the fraction of mass retained by the target,” Meng-Hua Zhu, a scientist at China’s Macau University of Science and Technology, said by email.

Zhu’s team modeled how much material the Moon collected from impacts on the basis of their size and the angle at which they hit. The researchers assumed that the more massive Earth retained the bulk of the precious metals delivered to it, an assumption that Simone Marchi calls “reasonable.” Marchi is a researcher at the Southwest Research Institute in Colorado who models the formation and bombardment of terrestrial planets and the Moon.

The new research reveals that the Moon holds on to only about 20% of the material that it collides with, 3 times less than previously assumed.Previous simulations had suggested that the Moon held on to roughly 60% of the material that collided with it, but that still was not enough to explain the HSE difference. Zhu’s team made more detailed simulations of lunar collisions that included a wider variety of impactor sizes, velocities, and angles than ever before. The researchers found that the Moon’s smaller size and lower gravity mean that most of the impacting material didn’t stick around and either escaped the Moon’s gravitational grasp or was blown completely from the surface. Although rocks that slammed head-on into the Moon became a permanent part of the lunar composition, other objects only skimmed the surface.

The new research reveals that the Moon holds on to only about 20% of the material that it collides with, 3 times less than previously assumed.

“This strikingly low value changes previous considerations on the Moon’s late accretionary history and suggests that significantly more material must have hit the Moon for a given HSE budget than previously envisioned,” Zhu said.

The new research was published in the journal Nature.

A Magma Ocean

The amount of debris lost from lunar collisions filled in only part of the discrepancy, bringing the Earth-Moon difference down to only about 100. So Zhu’s team turned to the lunar magma ocean.

After the collision that birthed the Moon, the surface of both worlds remained molten. Previous studies suggested that Earth’s magma surface took somewhere between 5 million and 10 million years to solidify into a rocky crust. Apollo samples suggest that the smaller Moon took longer to solidify, between 150 million and 200 million years, although not all scientists agree with this analysis. “It’s a problem that’s been debated for years,” says James Day, a geologist at the University of California, San Diego.

Assuming a long-lived molten mantle, material that slammed into Earth roughly 15 million years after the Moon formed would have polluted the terrestrial crust. But material colliding with the Moon at the same time would have been absorbed by its mantle and worked its way down to the core. The difference gives Earth a head start in collecting HSEs on its surface and could explain the rest of the discrepancy.

Although Day appreciates the implications of the new collisional model, he’s less certain about the molten magma explanation. “Purely from a geochemical point of view, that is still a problem,” he says. “I don’t think it’s a fatal flaw in their model by any stretch of the imagination, but it’s something that needs to be considered.”

Marchi also has concerns about the Moon’s magma ocean. According to the new research, the Moon should have 3–8 times more basins than those that visibly scar its surface today. Zhu argues that the magma ocean would quickly obliterate both crater rims and gravitational signatures, but Marchi isn’t certain. Although objects slamming into the Moon immediately after its formation should have been absorbed, it’s possible that cooling over the intervening tens of millions of years would have prevented a complete erasure of crater signatures.

“It may be possible, but I think it requires further investigation,” Marchi says.

—Nola Taylor Redd (@NolaTRedd), Freelance Journalist

The Search for the Impact That Cratered Ancient Scotland

Fri, 07/12/2019 - 13:52

Great Britain’s largest impact crater remains bafflingly hidden, despite continued investigation. The only clue comes from a blanket of material blown up by the impact 1.2 billion years ago, then rapidly covered by sediment.

Two geologists have staked their claims for the crater’s location—in opposite directions from leftover traces of the impact.

Along the northwest coast of Scotland, the Stac Fada Member deposits were long thought to have come from a volcano. Although the formation had been explored by scientists for well over a century, it wasn’t until 2006 that Ken Amor, then a Ph.D. student at the University of Oxford, found bits of shocked quartz that confirmed the site had formed when a space rock slammed into Earth.

“It’s not terribly surprising that they come to different conclusions. It’s an interesting and good mystery.”Now a geologist at Oxford, Amor has released a new paper with a more in-depth analysis of the region. Amor and his coauthors set the missing crater about 20 kilometers offshore, in the Minch channel that separates the Outer Hebrides from the northwest coast of mainland Scotland.

At the same time, Michael Simms, a geologist at National Museums Northern Ireland, has also published a paper expanding on his own previous research into the site of the impact. Simms suggests the missing crater is 50 kilometers east of the Stac Fada Member outcrop, beneath the town of Lairg, Scotland.

A competing location for the impact that cratered ancient Scotland lies under the town of Lairg. Credit: Olivier Porez/EyeEm/Getty Images

The contrasting conclusions shouldn’t be a surprise.

“They’re very different data sets,” says meteorite impact expert Jay Melosh, a geophysicist at Purdue University in Indiana who was not part of the research. “It’s not terribly surprising that they come to different conclusions. It’s an interesting and good mystery.”

Two Theories, No Craters

When a meteorite slams into the ground, it blasts a cloud of pulverized rock, hot gas, and molten material into the air. Heated gases lift the debris up, rapidly carrying it away from the impact site. Clouds of boiling gas and dust reach several hundred meters into the air. As they travel, they leave a trail of debris that can be traced back to the crater—but only if you’re fast enough.

On Earth, erosion and plate tectonics rapidly erode and cover these ejecta blankets. Most are gone in a few tens of millions of years, according to Melosh. Of the nearly 200 impact structures known to exist on our planet, only a handful of intact ejecta layers have survived. With so few Earth-bound examples, interpreting the details of the impact remains challenging.

Amor analyzed the magnetic minerals found inside the rocks themselves to determine how they arrived at their current location. The technique, well used in geology for determining the paths of ancient rivers and volcanic flows, has never before been used to determine the flow of an impact. Amor and his team sampled four locations and found they pointed toward a western source.

Simms took a different approach. In a 2015 paper, he examined the region around the ejecta and found a 40-kilometer-wide gravitational anomaly, the Lairg Gravity Low, that could be a crater remnant. Similar observations have been seen around other impact craters. After a meteor slams into Earth, the resulting crater soon fills with lighter material, leaving a less dense region. There’s just one problem: The supposed crater is buried beneath kilometers of this less dense debris.

In his new research, Simms worked with impact specialist Kord Ernstson of the University of Würzburg in Germany. Ernstson realized that the Scottish anomaly showed no sign of a central peak common to craters of similar size.

“It was a bit of an enigma,” Simms says.

Reconsidering Crater Size

But what if the anomaly itself was the central ring, with the larger crater rim eroded away? If so, the original crater would have been twice as large as suspected, nearly 100 kilometers across.

The proposed new crater size raised new problems. Something large enough to excavate an enormous crater would have dropped a thicker ejecta blanket.

But Earth’s crust is in constant motion. Lairg lies near the Moine Thrust Belt, a series of faults and upwellings that has changed the crust of the Scottish Highlands. Previous observations of the thrust suggest that the crust has moved significantly over hundreds of millions of years, and Simms reasoned that the shifting crust could have moved the crater anywhere from 40 to 60 kilometers closer to its ejecta blanket at Stac Fada.

“That is feasible given where [the supposed crater] is situated,” says Gordon Osinski, an impact crater specialist at Western University in London, Ontario, Canada.

“Basically, both papers are actually talking about some of the very same observations, but interpreting them differently. That is geology to a T.”Amor remains skeptical. Moving the crater farther east would have put the original impact in the ocean, and the ejecta should have contained marine sediment, none of which is found at Stac Fada. He also points to geologic observations of the region made nearly 3 decades ago, which call the similarity between the muddy sandstone of the ejecta blanket and the massive siltstones beneath them “remarkable.” The resemblance suggests that the ground beneath the impact crater was fairly similar, and thus fairly close, to the debris blanket.

“The impact debris therefore gives clues as the provenance of where the impact occurred,” Amor says.

Basing observations on the fortuitous location of a gravitational anomaly can be a bit tricky as well.

“Everybody knows gravity is inherently ambiguous,” Melosh says.

Even when they approach the ejecta the same way, the researchers disagree. Both teams looked at wedges of impact debris pushed along some of the layers of preexisting sandstone. The moving pressure wall would have pushed the ejecta against the existing rocks. However, whereas Simms interprets the wedges as having been pushed from east to west, Amor views them as having been pushed from west to east, resulting in predicted craters that lie in opposite directions.

“Basically, both papers are actually talking about some of the very same observations, but interpreting them differently,” says Osinski. “That is geology to a T.”

Crater Hunting

Determining which location is the site of Great Britain’s largest impact crater may take a bit more digging—literally.

The best way to tell whether a crater formed from a meteorite impact is to take a core sample. After drilling through material that settled over the crater during the past 1.2 billion years, geologists would hit the sludgy sediments that filled in the young impact. Beneath that should lie a thick sheet of rock melted by impact and then resolidified. A layer of fractured rock where the subsurface shattered from the impact filled in by melted rock would stretch for several kilometers under the melted rock.

“Even if the crater had been seriously eroded billions of years ago, you would still find evidence of fracturing,” Simms says.

Drilling into Simms’s gravitational anomaly would be a substantial and costly undertaking because the anomaly itself is buried by kilometers of rock. Amor’s crater might be a bit easier to probe—assuming it can be found.

Right now, Amor is poring over seismic reflection profiles conducted by oil companies around the United Kingdom in the 1970s and 1980s. Unfortunately, they aren’t the highest quality, but he says they remain the best hopes at present for direct evidence of an underwater crater.

Even better would be modern 3-D seismic observations, which could produce images of the remnants of the impact crater. “There should be something there,” Amor says.

The relatively easy access makes Amor’s theory more testable, according to Osinski.

Simms is also looking for another way to probe the ground beneath Laird. He’s hoping that he or another scientist might get the funding to do a more highly detailed gravitational survey, as the existing data are “a bit old.”

As for Osinski, he’s reserving judgment about which interpretation fits best until he can return to the site and take another look at the blocks with both perspectives in mind. He hopes Simms and Amor will do the same.

“I would hope these authors will go back and take a look at each other’s data,” he says.

And it’s entirely possible neither interpretation is correct.

“Maybe they’re both wrong, and there’s a third idea out there somewhere that people haven’t thought of yet,” Osinski says.

—Nola Taylor Redd (@NolaTRedd), Science Journalist

Gulf Dead Zone Looms Large in 2019

Thu, 07/11/2019 - 13:16

In 2019, predictions indicate that the Gulf of Mexico will retain the dubious distinction of having the second-largest low-oxygen dead zone on Earth (the Baltic Sea remains firmly in first place). By the end of the summer, the hypoxic region on the seafloor at the mouth of the Mississippi River is expected to occupy over 22,000 square kilometers—an area the size of the state of Massachusetts.

“The dead zone is driven by nitrogen and phosphorus runoff from agricultural operations that finds its way into the watershed and then into the Gulf.”The hypoxic zone, with oxygen levels less than 2 parts per million, forms every summer on the seafloor just off the coast of Texas and Louisiana, where the Mississippi and Atchafalaya watersheds drain into the Gulf of Mexico.

The dead zone probably started forming in the 1970s when farmers started applying more nitrogen-based fertilizers to crops across the Midwest, says Eugene Turner, an oceanographer at Louisiana State University in Baton Rouge and coauthor of the new forecast, released by the National Oceanic and Atmospheric Administration (NOAA) as part of a larger series of studies on the health of the Gulf.

“The dead zone is driven by nitrogen and phosphorus runoff from agricultural operations that finds its way into the watershed and then into the Gulf,” Turner says. The excess nutrients stimulate algae growth, and the decomposition of this algae on the seafloor leads to widespread hypoxic conditions.

Runoff and Rainfall

The new forecast models by Turner and his wife and coauthor, Nancy Rabalais, take into account the discharge rates of the Mississippi and Atchafalaya Rivers as well as U.S. Geological Survey estimates of the amounts of nitrate and phosphate being carried by the rivers. In the month of May alone, 156,000 metric tons of nitrate and 25,300 metric tons of phosphorus were deposited into the Gulf of Mexico.

This year’s record-setting size is also due to the unusually high amounts of rainfall that flooded many parts of the Midwest this spring. The more rainfall there is, the higher the river flow is, which carries more nutrient runoff into the Gulf.

Turner and Rabalais have been conducting systematic survey cruises to map the Gulf dead zone since 1985. This year the cruise will sail the last week in July, when the dead zone usually begins peaking in size. The forecasts help guide the systematic survey cruises.

If a hurricane or large storm hits the Gulf before or during a cruise, the temporary mixing of the water column can make the dead zone appear smaller, says Katja Fennel, a biogeochemical oceanographer at Dalhousie University in Halifax, Nova Scotia, Canada, who is also a contributor to the larger NOAA-funded Gulf project.

“If you have a year with several big storms or hurricanes, they can disrupt the stratification of the water column and reoxygenate the bottom water,” Fennel says. “But the mixing is only temporary: A few weeks later, hypoxia will be reestablished.”

Mobile organisms like shrimp and fish tend to migrate out of the hypoxic zone, and the forecasts can also be used to plan shrimping and fishing expeditions in the Gulf, says Robert Hetland, a physical oceanographer at Texas A&M University in College Station who is not involved in the NOAA studies. “We don’t have a clear understanding yet of how hypoxia affects mortality rates, but there is some indication that it may affect the growth rates of some Gulf organisms,” resulting in smaller shrimp, he says.

Land Use

In 1997, the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force (also known as the Hypoxia Task Force) was established with the mission of reducing the size of the Gulf dead zone to less than 5,000 square kilometers, but so far, little progress has been made, Turner says.

“Land use practices can evolve with benefit to the nation, farmers, farmland, and the Gulf, but it will take time and persistence and good will.”“The only way to accomplish that goal is to reduce the nitrogen loading into the Mississippi,” he says. “In agriculture, there’s a lot of resistance towards changing land use practices. Farmers are embedded in an economic and political structure that makes it very difficult to change practices without serious economic consequences.”

So far, fertilizer load reductions in the United States have been voluntary with no mandated regulations. In Europe, mandatory limits were enacted about 15 years ago on rivers such as the Rhine.

“European rivers have been cleaned up quite dramatically, and coastal eutrophication is less of an issue in European waters,” Fennel says. “So it is possible to reverse these trends, but relying on volunteer efforts is not the most effective way to do it.”

“It is going to take a lot to change what has developed over 2 centuries,” Turner says. “Land use practices can evolve with benefit to the nation, farmers, farmland, and the Gulf, but it will take time and persistence and good will.”

—Mary Caperton Morton (@theblondecoyote), Science Writer

Giant Planets and Brown Dwarfs Form in Different Ways

Thu, 07/11/2019 - 13:13

Finding extrasolar planets is hard: They’re much fainter and smaller than the stars they orbit, and from our vantage point, they appear crammed next to an enormously bright spotlight.

But thanks to the Gemini Planet Imager Exoplanet Survey (GPIES), which recently wrapped up a direct imaging campaign of hundreds of stars, scientists are getting a more complete picture of these worlds and how they form.

GPIES results shed light on the evolutionary linkages among planets, brown dwarfs, and stars.Giant planets and their larger brethren—brown dwarfs, also known as “failed stars”—form according to different mechanisms, a result that sheds light on the evolutionary linkages among planets, brown dwarfs, and stars, the new data reveal.

Most extrasolar planets found to date have been spotted by looking for tiny blips in a star’s light as a planet passes in front or by measuring a star’s “wobble” due to a planet’s gravitational tug. The Gemini Planet Imager, an instrument mounted on the 8-meter Gemini South telescope in Chile, takes a different tack.

Since late 2014, GPIES has been observing young, nearby stars in near-infrared light. A tool called a coronagraph masks out each star’s light to reveal the presence of any dim companion objects, which may be up to a million times fainter. (Because the planets and brown dwarfs that Gemini Planet Imager looks for are young, roughly 10 million to 100 million years, they’re still releasing heat from their formation and glow in the near infrared.)

Combing through data from the first half of the survey, which included observations of 300 stars, scientists found six giant planets (defined as being between 2 and 13 times the mass of Jupiter) and three brown dwarfs (more than 13 times the mass of Jupiter). Armed with information about the planets’ and brown dwarfs’ masses, temperatures, sizes, and orbits, the researchers looked for trends.

“We wanted to answer some really basic questions,” said Eric Nielsen, an astronomer at Stanford University in Stanford, Calif., and a GPIES team member.

Nielsen and his colleagues found that all six of the giant planets orbited stars at least 50% more massive than the Sun, a surprise since these stars were relatively rare in the survey. “That’s pretty remarkable,” said Nielsen.

The brown dwarfs, on the other hand, all orbited lower-mass stars. The researchers also found that giant planets orbited their host stars at comparatively smaller distances than the brown dwarfs.

Diverse Formation in the “Middle Ground”

Together, these observations imply that giant planets and brown dwarfs form in different ways. That’s an important discovery because these objects represent a sort of astronomical “middle ground”: They’re more massive than rocky planets like Earth but less massive than hydrogen-burning stars like our Sun. Given these objects’ intermediate status between planets and stars, astronomers want to understand how they form.

The GPIES observations revealed that giant planets likely form via the accretion of smaller objects, a mechanism called core accretion. That’s also how Earth-sized planets form, astronomers believe. But brown dwarfs likely form more like stars, not planets, in a process called disk instability, in which a disk of gas and dust fragments into large clumps, which then attract one another via gravity. These findings were published last month in the Astronomical Journal.

“This is kind of the definitive survey of all the nearby stars.”“The exoplanet community is very interested in these results,” said Trent Dupuy, an astronomer at Gemini Observatory in Hilo, Hawaii, not involved in the research. “This is kind of the definitive survey of all the nearby stars.”

Nielsen and his colleagues look forward to repeating their analysis with the entire GPIES data set, which will include measurements from 531 stars and their companions.

A whole new set of observations may soon be possible as well, said Nielsen. Early next year, Gemini Planet Imager may receive an upgrade and be moved to the 8-meter Gemini North telescope in Hawaii. There will be a “whole new sky of stars” to analyze, said Nielsen.

—Katherine Kornei (@katherinekornei), Freelance Science Journalist

Resurrecting Interest in a “Dead” Planet

Thu, 07/11/2019 - 13:06

It’s been a quarter of a century since the Magellan spacecraft burned up as it plunged into the atmosphere of Venus.

The probe’s radar mapper, which peered through the planet’s clouds, had revealed a rugged surface of high “continents,” volcanic mountains, spidery domes, and deep canyons. Scientists interpreted the chaotic landscape as evidence of massive outpourings of molten rock that repaved the planet’s surface hundreds of millions of years ago. Modern-day Venus was considered dead, or almost so—a world whose craggy face had been frozen in time.

“These ideas developed that Venus is geologically dead—it had this catastrophic resurfacing and now is completely devoid of geologic activity,” said Suzanne Smrekar, a senior researcher at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

The Magellan spacecraft departing space shuttle Atlantis in 1989. It arrived at Venus on 10 August 1990 and ended its mission 4 years later. Credit: NASA

In the past few years, though, planetary scientists have looked at Magellan’s observations in new ways, leading them to develop a more nuanced picture of the planet’s history. The Magellan images, combined with observations by more recent orbiters, have provided hints that Venus could be quite active today.

The new findings have whetted the appetites of many researchers for new Venus missions—perhaps a “Magellan 2.0” orbiter to snap higher-resolution pictures of the surface and make better maps of the planet’s topography or a long-duration balloon that would measure volcanic eruptions through ripples in the planet’s atmosphere.

Such missions would teach us more not just about Venus, the scientists say, but also about Earth and a whole class of exoplanets.

“Venus is an Earth-sized planet and now—who knew?!—there are Earth-sized planets all over the galaxy,” said Martha Gilmore, a professor of geology at Wesleyan University in Middletown, Conn. “So now, Venus is even more relevant for that reason.”

Catastrophe Strikes Venus

Venus is described as Earth’s sibling world. The two planets are about the same size and mass and probably were made from the same mixture of raw ingredients.“You’re not in Kansas anymore—it’s the Oz of the two planets.”

The surface of Venus, though, is quite different from that of its planetary sibling.

“You’re not in Kansas anymore—it’s the Oz of the two planets,” said James Head, a professor of geological sciences at Brown University in Providence, R.I., and a member of the Magellan radar team.

Instead of yellow brick roads and poppy fields, however, Magellan revealed that this planetary Oz is paved with volcanic rock. Although other craft had used radar to peek through the obscuring clouds, none did so in such high resolution or for so long. Magellan orbited Venus for more than 4 years; during the first two, its synthetic aperture radar mapped almost all of the planet’s surface, most of it at resolutions of 100–250 meters per pixel.

Radar images revealed that more than 80% of the surface is volcanic, more than two thirds is covered by volcanic plains, and much of the rest is dominated by tesserae (regions of rugged, deformed terrain that are higher than the average elevation). The images also showed shield volcanoes up to 9 kilometers tall, pancake-shaped domes, arachnoids—concentric rings surrounded by fractures that look like spider webs—and other intriguing features.

A color-coded radar map, compiled primarily from Magellan observations, shows elevation differences on Venus. Higher areas, known as tesserae, are in white and tan. Lower regions, primarily volcanic plains, are in blue and green. This view is centered on 180° longitude. Credit: NASA/JPL/USGS

The images contained a surprising dearth of impact craters, though. Scientists counted fewer than 1,000 of them, relatively evenly distributed across the planet and all looking fairly fresh.

“So people hypothesized, ‘Gee, most of the craters aren’t modified, they’re evenly distributed, that would argue that there was some catastrophic resurfacing,’” said Head, who also served as a guest investigator on two earlier Soviet radar missions, Venera 15 and 16. “The idea was that all of this volcanic activity came out at the same time, then it stopped.”

Catastrophic resurfacing about 500 million years ago (give or take 250 million years) reigned as the leading description of Venus’s geologic history (or at least the idea that got the most attention) for years. And Head still said that although the repaving might not have happened in as short a time as originally supposed, it didn’t take long in geological terms.

“The hypothesis was modified to say that the crust itself was highly deformed, then the volcanic activity came out,” he said. “It’s got to be within tens to a hundred million years between each other. We need to go with a new radar mission to see the rate of volcanism and where the volcanism is to test that hypothesis.”

Or Does It?

Many scientists, though, have reinterpreted the surface in a less dramatic way. New maps of Venus have allowed scientists to study the landforms and their relationships to each other in more detail. These new views favor a more “steady state” interpretation, in which different areas of the planet were resurfaced at different times, over a much longer period.“I think the general view is that rather than this catastrophic resurfacing event, which sounds amazingly dramatic and kind of science fictiony, it’s much more piecemeal or episodic.”

“I think the general view is that rather than this catastrophic resurfacing event, which sounds amazingly dramatic and kind of science fictiony, it’s much more piecemeal or episodic,” said Paul Byrne, an assistant professor of planetary geology at North Carolina State University in Raleigh. “You have this process where a bit gets resurfaced, then another bit gets resurfaced, then another bit gets resurfaced. At a given time, the resurfacing is still formidable, but it’s not necessarily that the whole planet is overturning and vomiting out its guts at one time.”

“We can show beyond a shadow of a doubt that there was no catastrophic resurfacing,” added Vicki Hansen, a professor of geology at the University of Minnesota Duluth. “You can absolutely re-create the crater database without catastrophic resurfacing.” Her detailed mapping of roughly a quarter of the surface, Hansen said, demonstrates that it could have been sculpted over a period of up to a few billion years.

Most of the steady state models posit an era in which the tesserae formed, followed by creation of the vast volcanic plains, followed by an era of activity that built the volcanoes and related structures. And the same models agree that Venus is likely to be active today, which would support the idea of a resurfacing process that has played out gradually instead of catastrophically.

There’s little or no evidence, though, of Earth-like plate tectonics on present-day Venus. “We certainly don’t see an interconnected system of plate boundaries like on Earth,” said Smrekar.

That apparent lack of plate boundaries provides insights into Venus’s interior, said Robert Herrick, a research professor at the University of Alaska Fairbanks. It suggests that there’s little water in the lithosphere to help lubricate the motion of tectonic plates, for example. (On the other hand, recent studies have suggested that Venus’s interior may retain 75% of the water it was born with, compared with just 50% for Earth.)

In addition, the planet’s high surface temperature (about 740 kelvins) may prevent surface layers from cooling enough to become dense enough to sink into the mantle, which is a key tectonic process on Earth. “That makes plate tectonics very difficult on Venus,” Herrick said.

“Pack Ice” on a Hot World

“Venus has tectonism all over [its] surface—folds, faults, fractures, and other features.”Even without crustal plates, “Venus has tectonism all over [its] surface—folds, faults, fractures, and other features,” said Hansen. But its tectonic activity appears to be more small scale and regional. Work published last year by Byrne and his colleagues, for example, found evidence of “blocky” structures across much of the planet’s lowlands.

“A lot of those regions have a distinctive pattern of intersecting little mountain belts and rift zones—smaller than the ones on Earth,” Byrne said. “If you start mapping these things, you can convince yourself that there are low-lying discrete portions of the Venus crust that are physically independent from the areas around them.”

Byrne compares the behavior of these areas to pack ice. “Most of the tectonic activity—most of the deformation that affects the ice—goes into the edges of these rafts, these blocks,” he said. “So some parts pull apart, some parts push together, and some parts go side by side. And we think we’re seeing the comparable mechanism of behavior from much of the Venus lowlands.”

The studies have identified dozens of blocks, which range from a few hundred to about 1,500 kilometers wide, distributed across much of the planet. They show relative horizontal motions of up to tens of kilometers. They are found in plains that are thought to be some of the youngest regions on Venus, so it’s possible the blocks are continuing to move today.

“Understanding this isn’t just about understanding Venus. It’s also [about] looking to understand the rules that govern how rocky planets such as Venus and Earth behave in general.”Byrne said that the motions could be driven by plumes in the mantle below relatively thin portions of the lithosphere. Roiling convection in the mantle could crack weak layers of crust at depths of 10–15 kilometers, with that deformation propagating to the surface.

“We don’t see anything like this on any of the other solar system worlds,” Byrne said. “Understanding this isn’t just about understanding Venus. It’s also [about] looking to understand the rules that govern how rocky planets such as Venus and Earth behave in general.”

Hot Spots for a Hot Planet

Although there’s no eyewitness view of an erupting volcano, the circumstantial evidence of an active Venus is piling up, from possible activity around coronae to what appear to be recent deposits of volcanic ash atop Maat Mons, the planet’s tallest volcano.

Maat Mons, the tallest volcano on Venus, stands roughly 9 kilometers above the planet’s average elevation. Research suggests that its summit is covered with recently emitted ash. The vertical scale is exaggerated in this image, which was compiled from Magellan radar and altimetry data. Credit: NASA/JPL

“How recent is recent?” asked Smrekar. “Some new lab work suggests that it’s quite recent—years, not millions of years.”

A study published in 2012 found that the floors of many of Venus’s craters are “radar dark,” suggesting they’ve been partially filled with volcanic rock.

“That could be telling you that craters are continuously being filled and covered over everywhere,” said Herrick, who led the study based on 3-D views of Venus he compiled from overlapping tracks of Magellan observations.

Another 2012 study reported spikes in the amount of sulfur dioxide (SO2), a volcanic gas, in Venus’s upper atmosphere. Venus Express, a European Space Agency (ESA) satellite, detected a significant jump in the level of the compound above the clouds not long after it entered orbit in 2006. Since SO2 is quickly destroyed by sunlight, any found at those altitudes must have just arrived. The SO2 spike mimicked one detected by NASA’s Pioneer Venus orbiter in the early 1980s.

The researchers concluded that the most likely source of both spikes was the recent eruption of one or more volcanoes. Because of the vigorous rotation of the atmosphere, however, it was impossible to pinpoint the culprits.

Venus Express was more successful at isolating possible volcanic activity by discovering hot spots on the surface, reported in 2015. An infrared instrument detected the spots in Ganis Chasma, a rift valley that’s one of the youngest known regions on Venus. The four hot spots were consistent with the glow of lava hundreds of degrees warmer than the surrounding terrain, distributed in areas ranging from 1 to about 200 square kilometers.

“Everyone agrees, there is some volcanism on Venus,” said Herrick. “It could range from reasonably Earth-like to maybe a magnitude lower than Earth rates. I would tend to guess it’s toward the high end. I want it to be more active.”

Kick-Starting a New Era

Everyone agrees on one other point as well: We won’t know the full answers to Venus’s geologic past and present without more data.Why are we not sending legions of spacecraft to this thing to characterize its atmosphere, its surface, its interior?”

“There’s still a lot of life left in the Magellan data for us to explore,” said Byrne. “But [Venus is] an almost criminally underexplored world….Why are we not sending legions of spacecraft to this thing to characterize its atmosphere, its surface, its interior?”

A new radar orbiter could provide higher resolution than Magellan and produce much better topographic maps. (The horizontal scale of maps produced with Magellan’s altimeter is in the tens of kilometers.) It would allow scientists to look for changes on the surface during the 25 years since Magellan’s demise, such as lava flows or ash deposits. And it could obtain more detailed observations of possible volcanic gases.

Yet only two Venus orbiters—the only dedicated missions since the end of Magellan—have arrived at the planet since then: ESA’s Venus Express and Japan’s Akatsuki. Venus Express was a major success, and Akatsuki continues to operate today.

For the future, ESA is considering a Venus orbiter, EnVision, that would detect minute changes in the planet’s surface and probe up to 100 meters below the surface. A decision is expected in 2021. India also has announced plans to launch an orbiter in 2023.

NASA has shown little interest in Venus, concentrating instead on Mars and many of our solar system’s smaller bodies. It has pondered several proposed Venus missions over the past decade but has rejected them all.

Smrekar has served as principal investigator for several of the proposals to NASA and reprises the role this year. Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy (VERITAS), an orbiter with a radar system and an infrared instrument to look for volcanic activity and measure surface composition, was submitted to the Discovery program on 1 July. It (and a similar mission proposed to the New Frontiers program) was selected as a finalist in earlier reviews but failed to make the cut.

An artist’s rendering of the proposed VERITAS orbiter. Credit: NASA/JPL-Caltech

Scientists have proposed Venus landers as well, although the challenges of surviving the high temperature and intense surface pressure make them more daunting.

Other scientists have proposed balloons that would float through and below the clouds. Among other instruments, they could carry seismometers that would detect the vibrations of venusquakes or volcanic eruptions transmitted through the dense atmosphere. In the more benign conditions well above the surface, they might operate for weeks or longer, providing a broader look at geologic activity than any lander.“I have astronomer colleagues who come to me and say, ‘I’m studying these exoplanets and I’ve got 50 Venuses. What do we know?’”

Any proposal still faces stiff competition from other priorities. But Venus scientists say the discovery of possible Venus-like worlds in other star systems may stimulate new interest in the original.

“I have astronomer colleagues who come to me and say, ‘I’m studying these exoplanets and I’ve got 50 Venuses. What do we know?’” said Head. “This is great!…You’re not looking at the surface, but there’s a new perspective on things, and that’s really critical. That’s another dimension. The more we understand about Venus, the more we’re able to place these Venus-like exoplanets into context, and that will be really incredible.”

“We only need one mission to spark that interest in other researchers, in policy makers, and [in] the public,” said Byrne. “That might be all we need to kick-start a new golden age in Venus exploration.”

—Damond Benningfield (damonddb@aol.com), Freelance Journalist

Air-Sea Exchanges from a Wave-Following Platform

Thu, 07/11/2019 - 11:30

Turbulent fluxes are physical quantities that describe the exchanges of heat and momentum through the air-sea interface. They are critical to the processes of weather and climate change. A limited understanding of air-sea exchanges makes weather prediction difficult and lead to uncertainty in climate projection. A big challenge is the lack of efficient technology to make measurements.

Bourras et al. [2019] have obtained in-situ observations on a novel wave-following platform in four oceanic regions and under different conditions. Various parameterizations for surface fluxes and related coefficients are calibrated against the observations. The authors only collected data under moderate winds, thus observations on turbulent fluxes under strong winds (such as hurricane and typhoon) still require a breakthrough.

Citation: Bourras, D., Cambra, R., Marié, L., Bouin, M.‐N., Baggio, L., Branger, H., et al. [2019]. Air‐sea turbulent fluxes from a wave‐following platform during six experiments at sea. Journal of Geophysical Research: Oceans, 124. https://doi.org/10.1029/2018JC014803

—Lei Zhou, Editor, JGR: Oceans

Legislators Introduce Climate Emergency Resolution

Wed, 07/10/2019 - 17:35

“The national emergency is not the border. It’s the climate.”“The national emergency is not the border. It’s the climate,” U.S. Rep. Earl Blumenauer (D-Ore.) said at a 9 July briefing in which he, Rep. Alexandria Ocasio-Cortez (D-N.Y.), and Sen. Bernie Sanders (I-Vt.) announced that they were introducing in Congress a concurrent resolution that would declare a national climate emergency.

“The entire planet, including the United States, has 12 years to reverse the disastrous direction we’re heading into when it comes to greenhouse gas emissions,” Blumenauer said. “It’s time for Congress to take a stand.”

The resolution for Congress to consider states that “it is the sense of Congress that the global warming caused by human activities, which increase emissions of greenhouse gases, has resulted in a climate emergency.” This emergency severely affects the nation’s economic and social well-being, as well as its health, safety, and national security, according to the resolution, which currently has 33 cosponsors in the House. In addition, the resolution states that the climate emergency requires a massive mobilization at a national scale “to halt, reverse, mitigate, and prepare for the consequences of the climate emergency and to restore the climate for future generations.”

Declaring a “climate emergency is frankly acknowledging the actual scientific facts.”Declaring a “climate emergency is frankly acknowledging the actual scientific facts,” Ocasio-Cortez said at the briefing. “While we will constantly hear from opponents and climate deniers and climate delayers that we need to do more research and get more information, we know that that couldn’t be further from the truth. We know that the scientific consensus is here, that the solutions are right in front of us.”

Ocasio-Cortez is one of the sponsors of the proposed Green New Deal, an ambitious congressional resolution to achieve net-zero greenhouse gas emissions by 2050, among other goals. Declaring a climate emergency would help Congress to enact sweeping reforms and legislation to help people cope with climate change, she said. “In order for us to enact the scale of the solution, we have to acknowledge the scale of the problem, and that is exactly what declaring a climate emergency does.”

Blumenauer said that declaring a climate emergency is a first step to moving forward with the Green New Deal.

More than 700 governments in 16 countries have declared a climate emergency, including Portugal, the Greater London Authority, and New York City.

Taking On the Fossil Fuel Industry

“We are going to have to take on the greed of the fossil fuel industry and the ignorance of [President] Donald Trump and transform our energy system in a very bold way.”Sanders called climate change an existential threat to the planet and said that there is “a moral imperative” to deal with it. “We are going to have to take on the greed of the fossil fuel industry and the ignorance of [President] Donald Trump and transform our energy system in a very bold way,” he said.

At the briefing, representatives from several environmental advocacy groups said that they hope that some Republican members of Congress will support the resolution. “It’s ultimately pretty ludicrous that this [resolution] isn’t a complete consensus position by both Democrats and Republicans to understand the severity of the climate crisis and do something about it,” said Varshini Prakash, founder and executive director of Sunrise Movement, an organization advocating for the Green New Deal and other measures to fight climate change.

Margaret Klein Salamon, founder and executive director of The Climate Mobilization, a group calling for mass mobilization to reverse climate change, said, “We would love to work with Republicans, but we are totally unwilling to compromise on the truth of the scale of the emergency and the scale of the necessary response to protect humanity and the natural world.”

—Randy Showstack (@RandyShowstack), Staff Writer

Scientists Who Selfie from the Field

Wed, 07/10/2019 - 11:47

When the semester ends, many geoscientists abandon the cold air and fluorescent lights of laboratory research for more natural climes. They wade into swampy waters, scale steep mountainsides, climb into caves, sail the open seas, and traverse frozen tundra. They install seismic networks, drill ice cores, collect sediments, and measure streamflow. They teach the next generation of geoscientists to do the same.

This summer, AGU asked geoscientists to send in selfies from the field via social media and randomly selected five giveaway winners. Check out some standout fieldwork selfies that showcase exciting research done outside the lab. .

It’s Hammer Time

Hammer seismic at Mt. St. Helens May 2018 #FieldWorkSelfie #AGU100 pic.twitter.com/PYkBwbMZns

— Dr. Adam R. Mangel (@DrHydrogeofizz) June 17, 2019


A Field Researcher’s Best Friend

Flashback to a happy field day – never alone with a groundwater well by your side #AGU100 #FieldWorkSelfie pic.twitter.com/ATzvfj7Gch

— LeonieZH (@zh_leonie) June 14, 2019


Rockin’ Outcrops

Visiting the rocks ‘cus we rock Got the chance to witness the northeastern Taiwan coastal outcrops despite the pouring rain #AGU100 #FieldWorkSelfie pic.twitter.com/GORz3lorgx

— Haiyina H. A (@hayinoabio) June 14, 2019


Hazardous Selfies, for Professionals Only

Hello, @theAGU here are my entries for #FieldWorkSelfie for #AGU100. My photos are from our Geohazard Mapping in Abra Province, Luzon, Philippines. https://t.co/INWkSY9FKM pic.twitter.com/3VXGrTZIhn

— ˗ˏˋ Sir MarcNeil Amandy ˎˊ˗ (@MarcusNeil) June 17, 2019


Sun Is Shining in the Sky…

For my #AGU100 #FieldWorkSelfie, a few gems of being reeeeeallly sunburned on the @JuneauIcefield last summer (worth it). pic.twitter.com/f3nybgrPFb

— Elizabeth Case (@elizabeth_case) June 21, 2019


Sondes Like Important Work

About a month ago doing a test radiosonde launch, preparing for #NCAR #OTREC2019, a research field mission in Costa Rica that starts in August to study tropical convection at the E Pacific near the ITCZ #AGU100 #FieldWorkSelfie pic.twitter.com/pXofmA0F31

— Jose Martinez-Claros (he/him) (@xatruchNMT) June 14, 2019


A Glacier from a Different Age: 2007

Here's my #AGU100 #fieldworkselfie from Black Rapids Glacier about 12 years ago. @theAGU pic.twitter.com/4pyicfEJmJ

— Dan Shugar (@WaterSHEDLab) June 17, 2019


Mobile Data Are Probably Spotty Underground

#AGU100 #FieldWorkSelfie Ready to go 1km underground to Boulby Underground Laboratory @theAGU pic.twitter.com/hpjttKX3Tl

— Estela Garces (@_g_eStela) June 13, 2019


Well, That’s Not a Basic Selfie

@theAGU, here are photos of my amazing undergrads sampling an acid mine drainage stream for the #AGU100 #FieldworkSelfie https://t.co/bxM3V23DSY

— Rachel Gabor (@RiverChem) June 24, 2019


Selfie Near Everest? Check

Selfie was taken during field trip in Ngozompa Glacier, Everest region, Nepal #AGU100 #FieldWorkSelfie while taking ground control points (GCPs) for the UAV survey. pic.twitter.com/Kf0fMhUrj3

— MB CHAND (@MohanBChand) June 20, 2019


A Neat Hat Trick

My journey through ocean sciences is a story of ships and hats for #AGU100. #FieldWorkSelfie pic.twitter.com/s39yWoR36z

— Dr. Chloe Anderson (@chloerophyll_a) June 25, 2019


Not to Be Confused with Underhills of the Shire

here’s my contribution to #AGU100 #FieldWorkSelfie featuring the trench @egripcamp (2 years ago now.. ack) pic.twitter.com/1XUYbNFdwb

— Benjamin Keisling (@palaeobak) June 24, 2019


Climbing on the Roof of the World

2014 eastern Tibetan Plateau. Investigating the links between nonmarine deposition and crustal deformation in the Mula Basin #AGU100 #FieldWorkSelfie pic.twitter.com/R9QqmSDy0Q

— Will Jackson (@geologywill) June 25, 2019


We’re Thankful That Smell-O-Vision Is Science Fiction

Here's my #FieldWorkSelfie for #AGU100: me after camping in Antarctica for 50 days. Luckily this photo doesn't come with the smell… pic.twitter.com/hyrz0DZjsm

— Drew Christ (@drewchrist_geo) June 25, 2019


On the One Hand, Creative Selfie. On the Other Hand…Nope, Still Creative

First fieldwork for a project I developed myself: 2012, in Gubbio, Italy, at the moment the Dinosaurs died. Right hand: dinosaurs, left hand: no dinosaurs. This study helped show how fish responded to a mass extinction funded by @AmPhilSociety #AGU100 #FieldWorkSelfie @theAGU pic.twitter.com/xTH8UaCcz8

— Dr. Elizabeth Sibert (@elizabethsibert) June 27, 2019

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

AGU’s Thriving Earth Exchange Wins 2019 Power of A Summit Award

Wed, 07/10/2019 - 11:46

AGU has been awarded a Power of A Summit Award from the American Society of Association Executives (ASAE). ASAE’s highest honor, the Summit Award is given to “associations that go above and beyond their everyday mission to undertake initiatives that benefit America and the world.” ASAE members represent 7,400 organizations of all types, making this recognition for AGU especially noteworthy. Only six associations were selected for this honor in 2019.

A Collaborative Relationship

AGU’s Thriving Earth Exchange helps communities work with AGU member scientists to tackle local priorities related to resilience, sustainability, and environmental health.

“I am hopeful that this award will encourage more scientists to offer their skills to communities and more communities to reach out to scientists.”Thriving Earth Exchange matches communities with vetted and trained member scientists who help communities design and carry out projects that advance community goals, solve local problems, or deal with the impacts of global issues such as climate change, disasters, hazards, and pollution. Now in 100 localities, Thriving Earth Exchange brings communities together with AGU member scientists to tackle priorities related to resilience, sustainability, and environmental health and, in the process, has affected the lives of over 17 million people.

“AGU’s Thriving Earth Exchange is honored to have received a Power of A Summit Award from ASAE. This award is proof positive that scientific knowledge, combined with community knowledge, is a powerful way for ameliorating real-world problems in an inclusive and effective manner,” said AGU CEO/Executive Director Chris McEntee. “I am hopeful that this award will encourage more scientists to offer their skills to communities and more communities to reach out to scientists.”

Real People: Real Impact

Awardees were judged on three criteria:

Reach of Project or Program: Award-winning entries offer original or effective solutions to today’s societal or business problems. Embodying the Power of Associations: Award-winning entries effectively showcase how associations strengthen society through volunteerism, education, social responsibility, innovation, research, and problem solving. Objectives and Outcomes: Award-winning entries generate results that achieve the association’s defined and measurable objectives.

“Through AGU’s Thriving Earth Exchange, communities and scientists work together to do science that makes a concrete local impact—reducing pollution, protecting people from natural hazards, and building a future in which everyone can thrive. This recognition is a testament to the power of cooperation and the value of connecting science and community knowledge, and most of all, it’s a well-deserved shout out to our scientific volunteers and the community leaders they work with,” said Thriving Earth Exchange director Raj Pandya. “Special thanks to the Thriving Earth Exchange team, our advisory board, AGU leadership, and the AGU Board and Council. We share this award with many collaborators, including Higher Ground, the International City/County Management Association, National League of Cities, ICLEI USA, ISeeChange, EPA’s College/Underserved Community Partnership Program, and Public Lab.”

Power of A Summit Award winners will be formally recognized at the 20th Anniversary Power of A-Summit Awards Dinner on 2 October at the National Building Museum in Washington, D.C.

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

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