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  • richardmitnick 12:30 pm on May 14, 2019 Permalink | Reply
    Tags: , Bárðarbunga-Eruption at Holuhraun September 4 2014, Eos,   

    From Eos: “More Than 30,000 Earthquakes Trace the Movement of Magma” 

    From AGU
    Eos news bloc

    From Eos

    5.14.19
    Katherine Kornei

    Seismometers near Iceland’s Bárðarbunga volcanic system pinpointed thousands of earthquakes in 2014–2015, revealing where molten rock was moving underground before any eruptions occurred.

    1
    Bárðarbunga-Eruption at Holuhraun, September 4, 2014, https://www.flickr.com/photos/41812768@N07/15146259395/

    2
    As Iceland’s Bárðarbunga volcanic system erupts in the background, researcher Jenny Woods downloads data from a seismometer. Image courtesy of Cambridge Volcano Seismology. Credit: Jenny Woods

    Accurate forecasting of volcanic eruptions is life-saving science: Millions of people worldwide live in the shadow of a volcano.

    Researchers have now analyzed precise records of tens of thousands of earthquakes in Iceland and produced one of the most detailed pictures of how seismicity traces the movement of magma deep underground. These kinds of measurements, which reveal the location of molten rock, can be used to better predict when and where eruptions will occur, the scientists suggest.

    Lucky Placement

    Robert White, a geophysicist at the University of Cambridge in the United Kingdom, admits he was lucky. He and his colleagues on the Cambridge Volcano Seismology team had already installed over 60 seismometers near Iceland’s Bárðarbunga volcanic system when magma began moving underground in 2014.

    The instrumentation was intended for a neighboring volcano, but White and his collaborators soon realized the seismometers were perfectly placed to capture the rumblings of Bárðarbunga. “They were in just the right place,” said White. (The researchers also rushed to place 10 additional seismometers.)

    Bárðarbunga would go on to belch 1.6 cubic kilometers of molten rock, dwarfing the 2010 eruption of Eyjafjallajökull. The first eruption occurred for a few hours on 29 August, and the next one came on 31 August, this time lasting 6 months.

    Earthquakes and volcanic eruptions often go hand in hand: The movement of molten rock underground—a magmatic intrusion—triggers ground shaking as it deforms the surrounding rock.

    The Bárðarbunga magmatic intrusion cut a 48-kilometer-long path through Earth’s crust over the course of 2 weeks. And earthquakes were plentiful: White and his colleagues recorded over 30,000 ranging in magnitude from 0.5 to 3.5.

    Precise Triangulation

    White and his colleagues pinpointed the locations of the earthquakes in three-dimensional space by triangulation. By very precisely measuring—to within 0.001 second—how long it took the earthquake waves to travel to different seismometers, the researchers estimated locations with uncertainties of only about 100 meters. That’s about 10 times better than most other studies, said Jenny Woods, a volcano seismologist at the University of Cambridge and member of the research team.

    Using the locations of the recorded earthquakes, the researchers inferred that Bárðarbunga’s magma moved in fits and starts—sometimes it stalled, and sometimes it moved forward at nearly 5 kilometers per hour (roughly human walking speed).

    These kinds of measurements make it possible to track the path of magma underground, said Woods. “Monitoring microseismicity is one of the most important tools we have for tracking intrusions of magma in real time.”

    Their results were published earlier this year in Earth and Planetary Science Letters.

    This study highlights the importance of having a dense monitoring network, said Luigi Passarelli, a volcanologist at King Abdullah University of Science and Technology in Saudi Arabia not involved in the research. “[It] can lead to better understanding of physical processes and eventually to improved real-time risk mitigation.”

    White and his colleagues will be returning to Iceland this July to download data from the 27 seismometers still deployed around Bárðarbunga. Collecting these measurements is crucial because the volcano appears to be refilling with magma underground, said White. “It’s still active.”

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 1:34 pm on April 24, 2019 Permalink | Reply
    Tags: "Bringing Clarity to What Drives Auroras", , , , , Eos   

    From Eos: “Bringing Clarity to What Drives Auroras” 

    From AGU
    Eos news bloc

    From Eos

    4.24.19
    Mark Zastrow

    1
    In this image taken from the International Space Station, both diffuse and intense auroras are visible, produced by charged particles propelled into Earth’s atmosphere. Credit: NASA

    The most spectacular auroras are produced by electrons zipping from space into Earth’s atmosphere. Although Earth’s magnetic field repels most electrons before they reach any wisps of air, under special conditions they can penetrate into the atmosphere, striking air molecules and causing them to glow.

    But how exactly those electrons, which normally circulate in Earth’s magnetic field, are accelerated or pushed down into the atmosphere is not fully clear.

    It’s generally agreed that there are three main ways to generate this “auroral precipitation.” One is small pockets of strong electric field high above Earth—also known as quasi-static potential structures (QSPS)—which can whisk them down. Another is strong waves in Earth’s magnetic field in which field lines vibrate like a plucked string—called Alfvén waves—propelling the charged particles along. These two mechanisms produce the most intense bands, curtains, and sheets of auroras.

    The other main cause is higher-frequency waves in Earth’s magnetic field that don’t increase electrons’ speed but scatter them, nudging the particles into trajectories that carry them down into the atmosphere. Wave scattering produces a less vivid, diffuse auroral glow but is commonly thought to be responsible for the bulk of the total auroral energy.

    But it’s difficult to decipher which of these three is happening at any given time. They can be identified only indirectly by analyzing spacecraft data measurements. Plus, these different mechanisms can occur simultaneously, which researchers have been unable to disentangle.

    Now, Dombeck et al. [JGR Space Physics] have developed a classification scheme that resolves many of these ambiguities and can detect multiple mechanisms. Their method used 13 years of data from NASA’s Fast Auroral Snapshot Explorer (FAST), a satellite launched into Earth orbit in 1996.

    NASA Fast Auroral Snapshot Explorer (FAST)

    Crucially, its instruments can observe electrons traveling both down toward Earth and up into space. In contrast, the previous, widely used scheme was based on data from satellites that could measure only downward traveling electrons and could identify only a single mechanism at a time.

    Being able to see upward traveling electrons makes it easier to determine whether they were accelerated by electric field structures or magnetic field vibrations, as the former reflect upgoing electrons back toward Earth and the latter do not. When the team compared their results, they found that misclassifications were common under the previous scheme.

    Applying their method to FAST data paints a complex picture of electron precipitation: Most of the time, multiple mechanisms contribute, and frequently, all three appear in intense auroral storms.

    Intriguingly, their results may also contradict the view that wave scattering contributes most of the energy of electron precipitation: The authors found that on Earth’s nightside, two thirds of the energy input comes from intense precipitation that is mostly caused by QSPS and Alfvén waves.

    Using this new method to better understand the mechanisms responsible for auroral precipitation will also help scientists better understand how Earth’s magnetic fields interact with the stream of charged particles coming from the Sun and how this interaction produces hazardous solar storms.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 2:35 pm on April 23, 2019 Permalink | Reply
    Tags: "National Volcano Warning System Gains Steam", Eos, Eruptions have the potential to pose significant security and economic threats across the nation., It took more than a decade but a bill that funds U.S. volcano monitoring efforts and establishes a single system became law on 12 March., Kīlauea Volcano in Hawaii, Mount St. Helens in Washington State, Passage of Public Law No. 116-9 authorizing funding for the implementation of the NVEWS was introduced by Sen. Lisa Murkowski (R-Alaska), Since 1980 there have been 120 eruptions and 52 episodes of notable volcanic unrest at 44 U.S. volcanoes, Volcano Observatories: Alaska Volcano Observatory; California Volcano Observatory; Cascades Volcano Observatory; Yellowstone Volcano Observatory; Hawaiian Volcano Observatory,   

    From Eos: “National Volcano Warning System Gains Steam” 

    From AGU
    Eos news bloc

    From Eos

    4.23.19
    Forrest Lewis

    It took more than a decade, but a bill that funds U.S. volcano monitoring efforts and establishes a single system became law on 12 March.

    1
    The string of 2018 eruptions at Kīlauea Volcano in Hawaii resulted in about $800 million in damages but no loss of life. Credit: USGS

    Early in the morning on 17 May 2018, Hawaii’s Kīlauea Volcano unleashed a torrent of ash more than 3,000 meters into the sky. The explosion was just one noteworthy event in a months-long series of eruptions that destroyed more than 700 homes and caused $800 million in damage. Remarkably—thanks in large part to the relentless monitoring efforts of scientists at the Hawaiian Volcano Observatory (HVO)—no one died as a result of the destructive eruption sequence, which lasted into August.

    Across the country, in Washington, D.C., Senate lawmakers happened to meet that same day to vote on a topical piece of legislation: Senate bill 346 (S.346), the National Volcano Early Warning and Monitoring System Act. The Senate passed the bill by unanimous consent, marking a big step forward for a piece of legislation more than a decade in the making.

    2
    The 1980 eruption of Mount St. Helens in Washington was the most destructive volcanic eruption in U.S. history, responsible for the deaths of 57 people and $1.1 billion in damage. Credit: Austin S. Post, USGS.

    The bill sought to strengthen existing volcano monitoring systems and unify them into a single system, called the National Volcano Early Warning System (NVEWS), to ensure that volcanoes nationwide are adequately monitored in a standardized way.

    After ultimately lacking the floor time in the House necessary for a vote before the end of 2018, the bill was reintroduced as part of a larger package of natural resources–related bills at the start of the new Congress, which convened in January. The John D. Dingell, Jr. Conservation, Management, and Recreation Act (S.47) contained elements of more than 100 previously introduced bills related to public lands, natural resources, and water. This bill quickly breezed through Congress and was signed into law by President Donald J. Trump on 12 March; it’s now Public Law No. 116-9.

    Although the bipartisan effort and the bill’s other contents, including an urgent reauthorization of the recently expired Land and Water Conservation Fund, captured the media’s attention, Section 5001, National Volcano Early Warning and Monitoring System, will have lasting effects on the nation’s volcano hazard awareness and preparation.

    Volcano Observatories

    Only five U.S. volcano observatories monitor the majority of U.S. volcanoes, with support from the U.S. Geological Survey’s (USGS) Volcano Hazards Program and independent universities and institutions. These observatories are the Alaska Volcano Observatory in Fairbanks; the California Volcano Observatory in Menlo Park; the Cascades Volcano Observatory in Vancouver, Wash.; HVO; and the Yellowstone Volcano Observatory in Yellowstone National Park, Wyo.

    Volcanologists at these observatories monitor localized earthquakes, ground movement, gas emissions, rock and water chemistry, and remote satellite data to predict when and where volcanic eruptions will happen, ideally providing enough time to alert the local populace to prepare accordingly.

    The USGS has identified 161 geologically active volcanoes in 12 U.S. states as well as in American Samoa and the Northern Mariana Islands. More than one third of these active volcanoes are classified by the USGS as having either “very high” or “high” threat on the basis of their hazard potential and proximity to nearby people and property.

    Many of these volcanoes have monitoring systems that are insufficient to provide reliable warnings of potential eruptive activity, whereas at others, the monitoring equipment is obsolete. A 2005 USGS assessment identified 58 volcanoes nationwide as being undermonitored.

    “Unlike many other natural disasters…volcanic eruptions can be predicted well in advance of their occurrence if adequate in-ground instrumentation is in place that allows earliest detection of unrest, providing the time needed to mitigate the worst of their effects,” said David Applegate, USGS associate director for natural hazards, in a statement before a House subcommittee hearing in November 2017.

    During the 2018 Kīlauea eruption, HVO, the oldest of the five observatories, closely monitored the volcano and issued routine safety warnings. However, many volcanoes lack the monitoring equipment or attention given to Kīlauea. Of the 18 volcanoes identified in the USGS report as “very high threat,” Kīlauea is one of only three classified as well monitored (the other two are Mount St. Helens in Washington and Long Valley Caldera in California).

    Public Law No. 116-9 aims to change that. In addition to creating the NVEWS, the law authorizes the creation of a national volcano watch office that will operate 24 hours a day, 7 days a week. The legislation also establishes an external grant system within NVEWS to support research in volcano monitoring science and technology.

    4
    More than three of every four U.S. volcanoes that have erupted in the past 200 years are in Alaska (including Mount Redoubt, above). Credit: R. Clucas, USGS

    Volcanic Impacts

    Since 1980, there have been 120 eruptions and 52 episodes of notable volcanic unrest at 44 U.S. volcanoes, according to the USGS Volcano Hazards Program. The cataclysmic eruption of Mount St. Helens in 1980 was the most destructive, killing 57 people and causing $1.1 billion in damage.

    Although active volcanoes are concentrated in just a handful of U.S. states and territories, eruptions have the potential to pose significant security and economic threats across the nation. A 2017 report by the National Academies of Sciences, Engineering, and Medicine concluded that eruptions “can have devastating economic and social consequences, even at great distances from the volcano.”

    In 1989, for example, an eruption at Mount Redoubt in Alaska nearly caused a catastrophe. A plane en route from Amsterdam to Tokyo flew through a thick cloud of volcanic ash, causing all four engines to fail and forcing an emergency landing at Anchorage International Airport. More than 80,000 aircraft per year, carrying 30,000 passengers per day, fly over and downwind of Aleutian volcanoes on flights across the Pacific. The potential disruption to flight traffic as well as air quality issues from distant volcanoes poses serious health and economic risks for people across the United States.

    “People think they only have to deal with the hazards in their backyard, but volcanoes will come to you,” says Steve McNutt, a professor of volcano seismology at the University of South Florida in Tampa.

    National Volcano Early Warning and Monitoring System Act

    Passage of Public Law No. 116-9 authorizes funding for the implementation of the NVEWS. The bill recommends that Congress, during the annual appropriations process, appropriate $55 million over fiscal years 2019 through 2023 to the USGS to carry out the volcano monitoring duties prescribed in the bill.

    The bill was introduced by Sen. Lisa Murkowski (R-Alaska), first elected in 2002 and consistently the most steadfast champion of NVEWS legislation. Her home state of Alaska contains the most geologically active volcanoes in the country, and more than three of every four U.S. volcanoes that have erupted in the past 200 years are in Alaska. Often in concert with Alaska’s sole House representative, Don Young (R), Murkowski has introduced volcano monitoring legislation in nearly every congressional session since her election. Five bills over the past decade have stalled in committee without reaching the floor for a vote.

    “Our hazards legislation has become a higher priority because we realize that monitoring systems and networks are crucial to ensuring that Americans are informed of the hazards that we face,” Murkowski said in a speech at AGU’s Fall Meeting 2018 in Washington, D.C., last December. “They help us prepare and are crucial to protecting lives and property.”

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 1:57 pm on April 23, 2019 Permalink | Reply
    Tags: "Atacama’s Past Rainfall Followed Pacific Sea Temperature", A Lack of Rain and Records, “It seems that ‘wetter’ episodes in the recent past in the Coastal Cordillera between Antofagasta and Arica line up with El Niño–like conditions”, “Our record covers only the first glacial-interglacial cycle”, “Whether this pattern is representative for all glacial­-interglacial times has to be tested with longer paleoclimate records.”, Eos, Paleoclimatology, The abundance of some planktonic diatoms further indicates the existence of an ephemeral water body” meaning the basin may have periodically flooded to become a temporary lake., The researchers are working to see whether the El Niño–like pattern extends further back.   

    From Eos: “Atacama’s Past Rainfall Followed Pacific Sea Temperature” 

    From AGU
    Eos news bloc

    From Eos

    4.23.19
    Kimberly M. S. Cartier

    This is the first paleoclimate record of precipitation near Atacama’s hyperarid core and suggests that its moisture source is different from that of the Andes.

    1
    Past rainfall in the Atacama Desert may have coincided with El Niño–like conditions. The team that discovered this conducted a deep-drilling follow-up expedition in 2017, seen here. Credit: Jan Voelkel

    Even the driest place on Earth, the Atacama Desert in Chile, still sees intermittent rainfall. In the past 215,000 years, these sporadic rainfall events may have coincided with elevated sea surface temperatures nearby that resemble El Niño conditions.

    “The Atacama Desert experienced several interspersed episodes of ‘wetter,’ still arid, conditions,” Benedikt Ritter, a paleoclimatologist at the University of Cologne in Germany, told Eos. “We are exploring…the mutual evolutionary relationship between climate, geomorphology, and biological evolution.”

    Ritter and his team published these results last month in Scientific Reports.

    2
    In 2014, Benedikt Ritter and his team, seen here, used percussion drilling to extract a sediment core from the top 6 meters of a clay pan basin in the Atacama Desert. Credit: Damian Lopez

    A Lack of Rain and Records

    The hyperarid core of the Atacama Desert currently gets less than 2 millimeters of rainfall a year. Scientists don’t know when those conditions began or how often they were interrupted or for how long. The area’s sediment record for the most recent geologic period “appears like a white spot on the map,” Ritter said.

    Water runoff from the Altiplano, or Andean Plateau, to the east confuses sediment records in the hyperarid region, making it difficult to isolate local precipitation records.

    “The mostly barren landscape is almost undiscovered in terms of paleoclimate studies for the younger timescale,” Ritter said.

    Ritter and his team focused on a basin in the coastal mountain range, the Coastal Cordillera, that cuts through the hyperarid region. The basin’s location separates it from the surrounding mountain drainage networks, and its clay pan bottom helps it retain water. Sediment cores collected from this endorheic basin, the researchers hypothesized, should track past precipitation near the hyperarid core of the desert.

    Relatively Wet Periods

    The team used percussion drilling to collect a sediment core from the top 6.2 meters of the clay pan. The rock record spans the past 215,000 years and is the first paleoclimate record of the middle and upper Pleistocene for this region.

    The researchers looked at the size and composition of sediment grains as well as the abundance of fossilized microorganisms at different depths along the core. On the basis of these measures, they identified two significant wet times in the paleoclimate record: one around 200,000 years ago and a shorter period around 120,000 years ago.

    “Wet” is relative in the most arid place on the planet, Ritter said. “What we can tell, based on the sedimentological data, is that there was enough water available to transport coarse-grained sediment from the catchment into this pan.”

    Moreover, “the abundance of some planktonic diatoms further indicates the existence of an ephemeral water body,” meaning the basin may have periodically flooded to become a temporary lake.

    Atlantic Versus Pacific

    The researchers compared the timing of the basin’s wet periods with other nearby climate records and found something pretty surprising, Ritter said.

    “It seems that ‘wetter’ episodes in the recent past in the Coastal Cordillera, between Antofagasta and Arica, line up with El Niño–like conditions,” specifically, higher sea surface temperatures along the Chilean and Peruvian coasts, he explained.

    3
    The researchers extracted a pilot core, part of which is seen here, from a basin in the coastal mountain range of the Atacama. Credit: Tibor Dunai

    “The pattern is totally inverse to the Andes,” said Marco Pfeiffer, a geoscientist at the Universidad de Chile in La Pintana who has studied the Atacama’s paleolakes and paleoclimate. “In this sense, [the study] is extremely novel and without a doubt a great contribution to the local paleoclimatology.” Pfeiffer was not involved with this research

    Because Ritter’s team collected this sediment core from a basin near to, but not within, the hyperarid zone, “there is still the question [of whether] these results could be extrapolated to iconic sites of the hyperarid core such as Yungay,” Pfeiffer cautioned.

    Drilling Down Deeper

    “Our record covers only the first glacial-interglacial cycle,” Ritter said. “Whether this pattern is representative for all glacial­-interglacial times has to be tested with longer paleoclimate records.”

    The researchers are working to see whether the El Niño–like pattern extends further back. In 2017, they conducted a follow-up expedition to this region and drilled deeper into the clay pan. Their new cores reach 8 times deeper than their first, Ritter said.

    “This new deep drilling sediment record extends the published reconstructed paleoclimate in this part of the Atacama Desert to even older times,” he said. The team plans to publish these records in the near future.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 1:14 pm on April 22, 2019 Permalink | Reply
    Tags: "More Than a Million New Earthquakes Spotted in Archival Data", , , Earthquakes in California, Eos   

    From Eos: “More Than a Million New Earthquakes Spotted in Archival Data” 

    From AGU
    Eos news bloc

    From Eos

    19 April 2019
    Katherine Kornei
    hobbies4kk@gmail.com

    By reanalyzing seismic records, researchers found a plethora of tiny earthquakes in Southern California that trace new fault structures and reveal how earthquakes are triggered.

    1
    Little temblors like those detected in the new data are much more numerous than the building-toppling quakes like the one that ripped through San Francisco in 1906. Credit: The U.S. National Archives

    Every 3 minutes. That’s how often an earthquake struck Southern California from 2008 to 2017, new research published in Science shows.

    3
    National Geographic

    Scientists have discovered over 1.6 million previously unknown earthquakes, most of them tiny, by mining seismic records. These results, which constitute the most comprehensive earthquake catalog produced to date, reveal in detail how faults crisscross the Golden State and shed light on how one earthquake triggers others.

    “Having a better earthquake catalog is just like having a better microscope,” said Robert Skoumal, a geophysicist at the U.S. Geological Survey in Menlo Park, Calif., not involved in this study. “We are able to take a closer look at the location of faults, how those faults rupture, and how they interact with each other.”

    Small and Numerous

    A tenet of earthquake science motivated Zachary Ross, a seismologist at the California Institute of Technology in Pasadena, and his collaborators: Earthquake catalogs are always incomplete. That’s because small earthquakes, many of which are too tiny to feel, are always lurking below the limit of detectability. And these little temblors are much more numerous than the building-toppling, highway-churning beasts that make headlines.

    “For every magnitude unit you go down in size, you get about 10 times as many,” said Ross.

    Ross and his colleagues used data from over 500 seismometers in the Southern California Seismic Network to tease out small, previously unrecorded earthquakes.

    They used a technique called template matching, which involves using the seismic waveforms of known earthquakes as templates and then looking for matches in seismic data collected nearby.

    “The shaking that’s recorded…will look almost the same,” said Ross. “They’re seeing all the same rocks as they’re traveling along.”

    Down to the Noise

    “We’re basically at the noise level of the instrumentation.”
    Ross and his team combed through a decade of seismic records using over 280,000 earthquakes as template events. They found over 1.6 million new earthquakes as small as magnitude 0.3. Such low levels of ground shaking can also be caused by construction-related vibrations, ocean waves, and nearby aircraft, said Ross.

    “We’re basically at the noise level of the instrumentation.”

    Using small differences in the arrival times of seismic waves from an earthquake, the scientists calculated the hypocenter of each new event. This information, along with an earthquake’s timing and magnitude, allowed Ross and his colleagues to assemble detailed maps of Southern California’s earthquakes.


    Video by Caltech

    The new earthquake catalog does a far better job of tracing fault lines and revealing how earthquakes trigger others compared with older records, said Ross.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 3:50 pm on March 25, 2019 Permalink | Reply
    Tags: , , , Eos, , WOVO-World Organization of Volcano Observatories   

    From Eos: “Data from Past Eruptions Could Reduce Future Volcano Hazards” 

    From AGU
    Eos news bloc

    From Eos

    3.25.19
    Fidel Costa
    Christina Widiwijayanti
    Hanik Humaida

    Optimizing the Use of Volcano Monitoring Database to Anticipate Unrest; Yogyakarta, Indonesia, 26–29 November 2018.

    1
    Java’s Mount Merapi volcano (right), overlooking the city of Yogyakarta, is currently slowly extruding a dome. Mount Merbabu volcano (left) has not erupted for several centuries. Participants at a workshop last November discussed the development and use of a volcano monitoring database to assist in mitigating volcano hazards. Credit: Fidel Costa

    In 2010, Mount Merapi volcano on the Indonesian island of Java erupted explosively—the largest such eruption in 100 years.

    1
    Mount Merapi, viewed from Umbulharjo
    16 April 2014
    Crisco 1492

    Merapi sits only about 30 kilometers from the city of Yogyakarta, home to more than 1 million people. The 2010 eruption forced more than 390,000 people to evacuate the area, and it caused 386 fatalities. In the past few months, the volcano has started rumbling again, and it is currently extruding a dome that is slowly growing.

    Will Merapi’s rumblings continue like this, or will they turn into another large, explosive eruption? Answering this question largely depends on having real-time monitoring data covering multiple parameters, including seismicity, deformation, and gas emissions. But volcanoes can show a wide range of behaviors. A volcanologist’s diagnosis of what the volcano is going to do next relies largely on comparisons to previous cases and thus on the existence of an organized and searchable database of volcanic unrest.

    For over a decade, the World Organization of Volcano Observatories (WOVO) has contributed to the WOVOdat project, which has collected monitoring data from volcanoes worldwide. WOVOdat has grown into an open-source database that should prove very valuable during a volcanic crisis. However, there are many challenges ahead to reaching this goal:

    How do we standardize and capture spatiotemporal data produced in a large variety of formats and instruments?
    How do we go from multivariate (geochemical, geophysical, and geodetic) signals to statistically meaningful indicators for eruption forecasts?
    How do we properly compare periods of unrest between volcanic eruptions?

    Participants at an international workshop last November discussed these and other questions. The workshop was organized by the Earth Observatory of Singapore and the Center for Volcanology and Geological Hazard Mitigation in Yogyakarta. An interdisciplinary group of over 40 participants, including students and experts from more than 10 volcano observatories in Indonesia, the Philippines, Papua New Guinea, Japan, France, Italy, the Caribbean, the United States, Chile, and Singapore, gathered to share their expertise on handling volcano monitoring data, strategize on how to improve on monitoring data management, and analyze past unrest data to better anticipate future unrest and eruptions.

    Participants agreed on the need for a centralized database that hosts multiparameter monitoring data sets and that allows efficient data analysis and comparison between a wide range of volcanoes and eruption styles. They proposed the following actions to optimize the development and use of a monitoring database:

    develop automatic procedures for data processing, standardization, and rapid integration into a centralized database platform
    develop tools for diagnosis of unrest patterns using statistical analytics and current advancement of machine learning techniques
    explore different variables, including eruption styles, morphological features, eruption chronology, and unrest indicators, to define “analogue volcanoes” (classes of volcanoes that behave similarly) and “analogue unrest” for comparative studies
    develop protocols to construct a short-term Bayesian event tree analysis based on real-time data and historical unrest

    Volcano databases such as WOVOdat aim to be a reference for volcanic crisis and hazard mitigation and to serve the community in much the same way that an epidemiological database serves for medicine. But the success of such endeavors requires the willingness of observatories, governments, and researchers to agree on data standardization; efficient data reduction algorithms; and, most important, data sharing to enable findable, accessible, interoperable, and reusable (FAIR) data across the volcano community.

    —Fidel Costa (fcosta@ntu.edu.sg), Earth Observatory of Singapore and Asian School of the Environment, Nanyang Technological University, Singapore; Christina Widiwijayanti, Earth Observatory of Singapore, Nanyang Technological University, Singapore; and Hanik Humaida, Center for Volcanology and Geological Hazard Mitigation, Geological Agency of Indonesia, Bandung

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 1:23 pm on March 22, 2019 Permalink | Reply
    Tags: "New Antenna Design Could Improve Satellite Communications", , Circular polarization of the signal allows for disturbances in the atmosphere that cause the electromagnetic signal to rotate as it travels to and from the ground, Circular polarization of the signal allows the satellite and the ground station to maintain communication even if the satellite rotates relative to the receiver, Eos, The data collected by a satellite are only as good as the signal it sends back to Earth and the signal it sends back is only as good as the antenna that sends it, Turkmen and Secmen design model and fabricate a new type of omnidirectional and circularly polarized slotted antenna that improves on existing designs in a number of ways.   

    From Eos: “New Antenna Design Could Improve Satellite Communications” 

    From AGU
    Eos news bloc

    From Eos

    14 March 2019
    David Shultz

    1
    The new omnidirectional circularly polarized slotted antenna. Credit: Turkmen and Secmen [2018]

    A novel antenna design promises to improve bandwidth and allow for better communication between Earth stations and satellites.

    The data collected by a satellite are only as good as the signal it sends back to Earth, and the signal it sends back is only as good as the antenna that sends it. Modern satellites come equipped with various sorts of antennas, all of which are designed to send and receive data by transmitting and interpreting pulses of electromagnetic radiation. Most satellites operate in a portion of the microwave spectrum known as the Kᵤ band, which spans wavelengths ranging from 1.67 to 2.5 centimeters and frequencies between 12 and 18 gigahertz.

    In a new study, Turkmen and Secmen [Radio Science] design, model, and fabricate a new type of omnidirectional and circularly polarized slotted antenna that improves on existing designs in a number of ways. The word “omnidirectional” is used to describe antennas that transmit their signal isotropically, meaning the pattern of radiation is the same no matter where the receiver is placed relative to the transmitter. Although perfectly isotropic transmission remains impossible, researchers can manipulate the signal in several ways to reduce its directionality. Omnidirectional antennas have several advantages, most notably in their ability to transmit around landforms such as mountains or, in the case of satellites, around the curvature of Earth, allowing researchers to maintain constant contact with the orbiter and detect any faults.

    Similarly, circular polarization of the signal allows the satellite and the ground station to maintain communication even if the satellite rotates relative to the receiver or if disturbances in the atmosphere cause the electromagnetic signal to rotate as it travels to and from the ground.

    Here the authors propose a new antenna designed to create the truest omnidirectional radiation pattern yet. It uses a special waveguide (a hollow structure that controls and aims the electromagnetic radiation) that transitions from a rectangular shape to a cylindrical one (see the image above). Like a sound wave traveling through an organ pipe, the satellite signal propagates through the wave guide, and the unique shape coaxes the signal into a pattern known as the TM01 mode, which also improves the omnidirectionality of the signal.

    To improve the signal’s quality even further, the researchers placed nonidentical antennae array slots in a geometrically symmetric pattern along the waveguide (see the image above). This modification was done to decrease the gain variation in the signal in the azimuthal plane in a wider frequency bandwidth. Gain describes how much a signal is amplified, and low variations in gain are crucial for achieving an omnidirectional radiation pattern. The end result, the researchers say, doubles the bandwidth of the satellite at the 12-gigahertz frequency.

    See the full article here .

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    Please help promote STEM in your local schools.

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    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 2:12 pm on March 11, 2019 Permalink | Reply
    Tags: "Making the First National Seafloor Habitat Map", , Eos, In the first months since its release Seamap Australia is already being used widely particularly by governmental agencies, Other organizations have produced data viewers for seafloor maps., Scientists faced many technological challenges in the development of Seamap Australia., Seamap Australia integrates seafloor maps with information on plant and animal habitats environmental stressors and resource management to create a first-of-its-kind resource., The International Hydrographic Organization along with the U.S. National Oceanic and Atmospheric Administration (NOAA) have just released their Data Centre for Digital Bathymetry data viewer, The primary role of Seamap Australia was to maximize performance and usability by reducing data to a manageable size, This resource makes Australia the first continent to have released a benthic marine habitat map with a singular nationally consistent classification scheme.   

    From Eos: “Making the First National Seafloor Habitat Map” 

    From AGU
    Eos news bloc

    From Eos

    3.11.19
    Vanessa Lucieer
    Craig Johnson
    Neville Barrett

    Seamap Australia integrates seafloor maps with information on plant and animal habitats, environmental stressors, and resource management to create a first-of-its-kind resource.

    1
    The critically endangered spotted handfish is found only in Tasmania’s Derwent estuary. Handfish crawl rather than swim, using their handlike pectoral and pelvic fins. Seamap Australia assists efforts to protect species like this by integrating information on seafloor habitats with bathymetric maps for resource management and environmental studies. Credit: Rick Stuart-Smith/Reef Life Survey, CC BY 3.0

    Imagine that the ocean could be drained to reveal the landscape of the seafloor around Australia. Now imagine that we could overlay on this landscape a map of the various seafloor types and the ways that marine animals and plants are distributed across these seafloor types. Even better, imagine being able to easily visualize all these factors in relation to resource management boundaries or factors that place stress on marine environments.

    Draining the ocean isn’t possible, of course, but a large team of Australian scientists has done the next best thing. By collating spatial information on seafloor habitats from a wide range of collaborating agencies and universities, they’ve produced Seamap Australia, an interactive mapping service and database that spans the coastal marine region from the coastline to the shelf break, 200 meters below the surface of the water. The extent of the survey data represents all marine habitat surveys to 2017, comprising a total of 6.5% of Australia’s marine jurisdiction, which at 13.9 million square kilometers is the third largest in the world.

    2
    One Australia Sea Map

    This resource makes Australia the first continent to have released a benthic marine habitat map with a singular, nationally consistent classification scheme. This information release is relevant to the current motivations of the international community as we work toward mapping the gaps in bathymetric data across the world’s oceans. Seamap Australia is a national habitat map derived from both bathymetry and associated ground truthing of biological communities and sediment composition.

    Beyond Bathymetry

    Other organizations have produced data viewers for seafloor maps. The International Hydrographic Organization along with the U.S. National Oceanic and Atmospheric Administration (NOAA) have just released their Data Centre for Digital Bathymetry (DCDB) data viewer, just as Geological Survey Ireland and the Marine Institute have produced Integrated Mapping for the Sustainable Development of Ireland’s Marine Resource (INFOMAR). However, these viewers are solely for bathymetric data, not data classified into seafloor habitats.

    Bathymetric data are the foundation of benthic habitat mapping. From high-resolution bathymetry data, we can extract information on the surface structures and geological features of the seafloor—its geomorphology. This information, in turn, gives us clues about such seafloor habitats as reefs and sediment.

    From high-resolution benthic habitat maps, environment managers can visualize where the habitats are that need protection, such as reefs and sea grasses. They can also identify areas where marine life production is at its highest.

    Putting Seamap Australia to Use

    In the first months since its release, Seamap Australia is already being used widely, particularly by governmental agencies. These include Australian government agencies such as Parks Australia—the agency now has ready access to habitat and bathymetry data within marine parks and reserves nationwide. Feedback on government needs will help to clarify future plans to include information on threatened species and cultural values, which will be used to address future stressors.

    4
    Seamap Australia integrates bathymetric maps, benthic habitat data, biodiversity estimates, fishing activity data, and other elements, incorporating FAIR data principles.

    The Australian Department of Agriculture and Water Resources uses Seamap Australia for biosecurity management in determining habitat suitability for, and distribution of, marine pest species. The National Environmental Science Program Marine Biodiversity Hub uses Seamap Australia for end-to-end delivery of data and information to meet state-of-the-environment reporting to the Australian government—an internationally accepted framework for assessing resilience, emerging risks, and outlooks for the marine environment. Seamap Australia has proven to significantly reduce the time and effort required to locate and download reliable and relevant marine spatial data.

    In Australia, less than 25% of the seabed within Australia’s exclusive economic zone has been bathymetrically surveyed at high resolution. Australia is striving to coordinate its seabed mapping activities to bring government, industry, and universities together to fully use the skills, resources, and data available. Initiatives such as Seamap Australia have the capacity to develop a collaboration between the national and international community where the development of spatial analysis tools and better standards for habitat classification can be registered, assessed, and shared.

    A Challenging Effort

    Scientists faced many technological challenges in the development of Seamap Australia. Seeking and accessing available seabed habitat data were the first hurdle: The marine community needed to be encouraged to upload their spatial data into national geodatabases where they could be harvested for this project.

    After clearing the first hurdle—finding the data—classifying the data was the second challenge to be solved. Not every country enjoys Australia’s level of access to resources for marine surveys, but even Australia presented some difficulty. There is no coordination of survey effort nationwide, so knowing where data have been collected was the first knowledge gap that had to be filled. Seamap Australia scientists also learned that although national geospatial agencies might produce survey data, they do not process these data to a level at which they can be used to produce maps such as habitat maps.

    Expert development of a single habitat classification schema enabled us to assimilate disparate data sources of variable scale, resolution, and collection technology to create the continental-scale spatial layer. From a big data perspective, the website needed to condense petabytes of unprocessed field data into a single unified mapping layer.

    The primary role of Seamap Australia was to maximize performance and usability by reducing data to a manageable size (the total collection is about 25 gigabytes). However, our success relied on overcoming competing interests of contributors, establishing a culture of data sharing, and achieving national agreement on a classification schema and the associated vocabulary.

    All seafloor habitat data sets used by Seamap Australia are now publicly accessible from the platform under a Creative Commons license. We recognized the need for a central aggregation service, so we scoped the requirements for a system that would deliver a simple and intuitive visualization tool based on a distributed data model.

    Developers considered the most relevant technology for interoperability and integration with other systems. Seamap was designed to be scalable, involving careful trade-offs around data access and computation. Technologies used to achieve performance at large scales included load balancing and caching, a stateless application architecture, and distribution across multiple hosts to reduce the impact on a single server. A custom application program interface (API) enables novel features such as construction of “on the fly” cross sections of the seabed, and it provides innovative “smart” selection of data sets most relevant at different spatial scales for download in a variety of formats.

    Moving the Field Forward

    It is widely recognized that making data findable, accessible, interoperable, and reusable (FAIR) is the way forward for research. Anyone can easily find, access, use, and share FAIR data.

    Collaborative partnership with Seamap Australia will foster growth of knowledge of marine environments and ecosystems within the vast jurisdiction of the Australian marine estate. Only the future will tell whether Seamap Australia has helped to address this goal, but for this project to succeed, future surveys will need to accede to the principles of FAIR data.

    National initiatives such as Seamap Australia and international initiatives such as Seabed 2030 support an environment in which the public and private sectors can come together. This type of collaboration paves the way to provide ocean science, data, and information to inform policies for a well-functioning ocean, one of the two major goals of the United Nations Decade of Ocean Science for Sustainable Development (2021–2030), which supports the 2030 Agenda for Sustainable Development.

    Projects such as Seamap Australia enable new projects of national scope that are relevant in terms of scale (nationwide) and timeliness (almost live) to the United Nations Decade of Ocean Science. This type of effort is the only way that we can improve knowledge of our vast marine estate and complete the remaining 75% of Australia’s bathymetric map.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 2:24 pm on February 18, 2019 Permalink | Reply
    Tags: , , , Eos, Rising Temperatures Reduce Colorado River Flow   

    From Eos: “Rising Temperatures Reduce Colorado River Flow” 

    From AGU
    Eos news bloc

    From Eos

    2.18.19
    Sarah Stanley

    1
    New research teases out the relative roles of hotter temperatures and declining precipitation in reducing the flow volume of the Colorado River, which feeds Lake Mead, pictured here [and much more]. Credit: John Fleck

    The Colorado River flows through seven U.S. states and northern Mexico, before discharging into the Gulf of California. Along the way, it provides drinking water to millions of people and irrigates thousands of square kilometers of cropland. However, although annual precipitation in the region increased by about 1% in the past century, the volume of water flowing down the river has dropped by over 15%.

    New research by Xiao et al. [Water Resources Research]. examines the causes behind this 100-year decline in natural flow, teasing out the relative contributions of rising temperatures and changes in precipitation. This work builds on a 2017 paper [Water Resources Research] showing that rising temperatures played a significant role in reduced flows during the Millennium Drought between 2000 and 2014.

    Rising temperatures can lower flow by increasing the amount of water lost to evaporation from soil and surface water, boosting the amount of water used by plants, lengthening the growing season, and shrinking snowpacks that contribute to flow via meltwater.

    To investigate the impact of rising temperatures on Colorado River flow over the past century, the authors of the new paper employed the Variable Infiltration Capacity (VIC) hydrologic model. The VIC model enabled them to simulate 100 years of flow at different locations throughout the vast network of tributaries and subbasins that make up the Colorado River system and to tease out the effects of long-term changes in precipitation and temperature throughout the entire Colorado River.

    The researchers found that rising temperatures are responsible for 53% of the long-term decline in the river’s flow, with changing precipitation patterns and other factors accounting for the rest. The sizable effects of rising temperatures are largely due to increased evaporation and water uptake by plants, as well as by sublimation of snowpacks.

    Additional simulations with the VIC model showed that warming drove 54% of the decline in flow seen during the Millennium Drought, which began in 2000 (and is ongoing). Flows also declined because precipitation fell on less productive (i.e., more arid) subbasins rather than on highly productive subbasins near the Continental Divide. This contrasts strongly with an earlier (1950s–1960s) drought of similar severity, which was caused almost entirely by below-normal precipitation over most of the basin.

    The authors note that the situation is complex, given different long-term trends and drought response across the basin, as well as seasonal differences in temperature and precipitation. Still, the new findings support an argument from the 2017 research that as global warming progresses, the relative contribution of rising temperatures to decreased Colorado River flow will increase.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 3:49 pm on January 28, 2019 Permalink | Reply
    Tags: , Eos, NASA Magnetospheric Multiscale Mission,   

    From Eos: “New Plasma Wave Observations from Earth’s Magnetosphere” 

    From AGU
    Eos news bloc

    From Eos

    1.28.19
    Terri Cook

    NASA Magnetospheric Multiscale Mission

    Plasmas are swirling mixtures of gas so hot that many of the constituent atoms have been stripped of their electrons, creating a dynamic field of both negatively and positively charged particles that are strongly influenced by magnetic and electrical fields. Plasmas account for more than 99% of matter in the universe and can disrupt satellite navigation systems and other technologies, but scientists are still working to understand the fundamental processes occurring within them.

    Usanova et al. report new observations of plasma waves in the magnetosphere, the region surrounding our planet where Earth’s magnetic field controls the charged particles. Using data from the FIELDS instruments aboard NASA’s Magnetospheric Multiscale satellites, the team identified a series of electromagnetic ion cyclotron waves—high-frequency oscillations that can be divided into several bands on the basis of their vibrational frequencies—within the plasma sheet boundary layer during a 3-day period in May of 2016.

    In addition to measuring multiple harmonics of these waves in the oxygen frequency band, the satellite instruments also unexpectedly detected other accompanying waves, including higher-frequency broadband and whistler mode chorus waves that modulate at the same frequency. By presenting the first simultaneous observations of these various wave types, this study is likely to open up an entirely new area of inquiry into cross-frequency wave interactions at both electron and ion scales.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
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