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  • richardmitnick 2:13 pm on December 18, 2014 Permalink | Reply
    Tags: , Carbon studies, , NASA Orbiting Carbon Observatory-2   

    From JPL: “NASA’s Spaceborne Carbon Counter Maps New Details” 

    JPL

    December 18, 2014
    Carol Rasmussen
    NASA Earth Science News Team

    The first global maps of atmospheric carbon dioxide from NASA’s new Orbiting Carbon Observatory-2 mission demonstrate its performance and promise, showing elevated carbon dioxide concentrations across the Southern Hemisphere from springtime biomass burning.

    At a media briefing today at the American Geophysical Union meeting in San Francisco, scientists from NASA’s Jet Propulsion Laboratory, Pasadena, California; Colorado State University (CSU), Fort Collins; and the California Institute of Technology, Pasadena, presented the maps of carbon dioxide and a related phenomenon known as solar-induced chlorophyll fluorescence and discussed their potential implications.

    A global map covering Oct. 1 through Nov. 17 shows elevated carbon dioxide concentrations in the atmosphere above northern Australia, southern Africa and eastern Brazil.

    g
    Global atmospheric carbon dioxide concentrations from Oct. 1 through Nov. 11, as recorded by NASA’s Orbiting Carbon Observatory-2. Image credit: NASA/JPL-Caltech

    2
    This map shows solar-induced fluorescence, a plant process that occurs during photosynthesis, from Aug. through Oct. 2014 as measured by NASA’s Orbiting Carbon Observatory-2. Image credit: NASA/JPL-Caltech

    “Preliminary analysis shows these signals are largely driven by the seasonal burning of savannas and forests,” said OCO-2 Deputy Project Scientist Annmarie Eldering, of JPL. The team is comparing these measurements with data from other satellites to clarify how much of the observed concentration is likely due to biomass burning.

    The time period covered by the new maps is spring in the Southern Hemisphere, when agricultural fires and land clearing are widespread. The impact of these activities on global carbon dioxide has not been well quantified. As OCO-2 acquires more data, Eldering said, its Southern Hemisphere measurements could lead to an improved understanding of the relative importance in these regions of photosynthesis in tropical plants, which removes carbon dioxide from the atmosphere, and biomass burning, which releases carbon dioxide to the atmosphere.

    The early OCO-2 data hint at some potential surprises to come. “The agreement between OCO-2 and models based on existing carbon dioxide data is remarkably good, but there are some interesting differences,” said Christopher O’Dell, an assistant professor at CSU and member of OCO-2’s science team. “Some of the differences may be due to systematic errors in our measurements, and we are currently in the process of nailing these down. But some of the differences are likely due to gaps in our current knowledge of carbon sources in certain regions — gaps that OCO-2 will help fill in.”

    Carbon dioxide in the atmosphere has no distinguishing features to show what its source was. Elevated carbon dioxide over a region could have a natural cause — for example, a drought that reduces plant growth — or a human cause. At today’s briefing, JPL scientist Christian Frankenberg introduced a map using a new type of data analysis from OCO-2 that can help scientists distinguish the gas’s natural sources.

    Through photosynthesis, plants remove carbon dioxide from the air and use sunlight to synthesize the carbon into food. Plants end up re-emitting about one percent of the sunlight at longer wavelengths. Using one of OCO-2’s three spectrometer instruments, scientists can measure the re-emitted light, known as solar-induced chlorophyll fluorescence (SIF). This measurement complements OCO-2’s carbon dioxide data with information on when and where plants are drawing carbon from the atmosphere.

    “Where OCO-2 really excels is the sheer amount of data being collected within a day, about one million measurements across a narrow swath,” Frankenberg said. “For fluorescence, this enables us, for the first time, to look at features on the five- to 10-kilometer scale on a daily basis.” SIF can be measured even through moderately thick clouds, so it will be especially useful in understanding regions like the Amazon where cloud cover thwarts most spaceborne observations.

    The changes in atmospheric carbon dioxide that OCO-2 seeks to measure are so small that the mission must take unusual precautions to ensure the instrument is free of errors. For that reason, the spacecraft was designed so that it can make an extra maneuver. In addition to gathering a straight line of data like a lawnmower swath, the instrument can point at a single target on the ground for a total of seven minutes as it passes overhead. That requires the spacecraft to turn sideways and make a half cartwheel to keep the target in its sights.

    The targets OCO-2 uses are stations in the Total Carbon Column Observing Network (TCCON), a collaborative effort of multiple international institutions. TCCON has been collecting carbon dioxide data for about five years, and its measurements are fully calibrated and extremely accurate. At the same time that OCO-2 targets a TCCON site, a ground-based instrument at the site makes the same measurement. The extent to which the two measurements agree indicates how well calibrated the OCO-2 sensors are.

    Additional maps released today showed the results of these targeting maneuvers over two TCCON sites in California and one in Australia. “Early results are very promising,” said Paul Wennberg, a professor at Caltech and head of the TCCON network. “Over the next few months, the team will refine the OCO-2 data, and we anticipate that these comparisons will continue to improve.”

    To learn more about OCO-2, visit:

    http://oco2.jpl.nasa.gov/

    NASA monitors Earth’s vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

    For more information about NASA’s Earth science activities this year, see:

    http://www.nasa.gov/earthrightnow

    See the full article here.

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    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 5:54 pm on December 7, 2014 Permalink | Reply
    Tags: , Carbon Dioxide, , Carbon studies,   

    From Huff Post: “These 6 Countries Produce Nearly 60 Percent Of Global Carbon Dioxide Emissions” 

    Huffington Post
    The Huffington Post

    12/05/2014
    DINA CAPPIELLO

    Six countries produce nearly 60 percent of global carbon dioxide emissions. China and the United States combine for more than two-fifths. The planet’s future will be shaped by what these top carbon polluters do about the heat-trapping gases blamed for global warming.

    How they rank, what they’re doing:

    CHINA

    s
    A general view shows residential and commercial buildings on a hazy day in Shanghai on November 21, 2014. AFP PHOTO / JOHANNES EISELE

    It emits nearly twice the amount of greenhouse gases as the United States, which it surpassed in 2006 as the top emitter of carbon dioxide. China accounts for about 30 percent of global emissions. U.S. government estimates show China doubling its emissions by 2040, barring major changes. Hugely reliant on fossil fuels for electricity and steel production, China until recently was reluctant to set firm targets for emissions, which continue to rise, although at a slower rate. That changed when Beijing announced last month in a deal with Washington that it would stem greenhouse gas emission growth by 2030. About a week later, China’s Cabinet announced a coal consumption cap by 2020 at about 62 percent of the energy mix. While politically significant, the U.S.-China deal alone is expected to have little effect on the global thermostat.

    2013 CO2 emissions: 11 billion tons

    2013 Population: 1.36 billion

    UNITED STATES

    2
    In this March 8, 2014 photo, steam from the Jeffrey Energy Center coal-fired power plant is silhouetted against the setting sun near St. Mary’s, Kansas. (AP Photo/Charlie Riedel, File)

    It has never entered into a binding treaty to curb greenhouse gases. Nevertheless, it has cut more carbon pollution than any other nation. It is on pace to meet a 2009 Obama administration pledge to reduce emissions 17 percent from 2005 levels by 2020. Carbon emissions are up, though, as the U.S. rebounds from recession. President Barack Obama has largely leaned on existing laws, not Congress, to make progress — boosting automobile fuel economy and proposing to reduce carbon pollution from new and existing power plants. The White House vowed in the China deal to double the pace of emissions reductions, lowering carbon pollution 26 percent to 28 percent from 2005 levels by 2025. Expect resistance when Republicans control Congress in January.

    2013 CO2 emissions: 5.8 billion tons

    2013 Population: 316 million

    INDIA

    3
    In this Tuesday, Sept. 23, 2014 photo, smoke rises from chimneys of brick kilns on the outskirts of New Delhi, India. (AP Photo/Altaf Qadri, File)

    The U.S.-China agreement puts pressure on the Indian government, which could announce new targets during a planned Obama visit in January. Meantime, India plans to double coal production to feed a power grid still suffering blackouts. Its challenge: to curb greenhouse gases as its population and economy grow. In 2010, India voluntarily committed to a 20 percent to 25 percent cut in carbon emissions relative to economic output by 2020 against 2005 levels. It has made recent strides installing solar power, which it is expected to increase fivefold to 100 gigawatts by 2030. Under current policies, its carbon dioxide emissions will double by then, according to the International Energy Agency.

    2013 CO2 emissions: 2.6 billion tons

    2013 population: 1.2 billion

    RUSSIA

    4
    Electrical light illuminates a petroleum cracking tower at the Lukoil-Nizhegorodnefteorgsintez oil refinery, operated by OAO Lukoil, in Nizhny Novgorod, Russia, on Thursday, Dec. 4, 2014. (Andrey Rudakov/Bloomberg via Getty Images)

    It never faced mandatory cuts under the 1997 Kyoto Protocol because its emissions fell so much after the Soviet Union collapsed. A major oil and gas producer, Russia in 2013 adopted a domestic greenhouse gas target that would trim emissions 25 percent from 1990 levels by 2020. Russia’s carbon dioxide emissions today average 35 percent lower than 1990 levels. To meet its goal, Russia has set a goal for 2020 of boosting energy efficiency 40 percent and expanding renewable energy 4.5 percent. The state-owned gas company Gazprom has energy conservation plans, as has the federal housing program. But in 2006, Russia announced a move to more coal- and nuclear-fired electricity to export more oil and natural gas.

    2013 CO2 emissions: 2 billion tons

    2013 population: 143.5 million

    JAPAN

    5
    A passenger jet flies over factory facilities in the Keihin Industrial Zone in Kawasaki City, near Tokyo, Japan, on Thursday, Nov. 13, 2008. (Toshiyuki Aizawa/Bloomberg via Getty Images)

    The shuttering of its nuclear power plants after the 2011 Fukushima nuclear disaster forced a drastic change in plans to curb carbon pollution. In November, Japanese officials said they would now reduce greenhouse gases 3.8 percent from 2005 levels by 2020. With more fossil fuels in the mix, Japan’s emissions will be up 3 percent from 1990 levels, its benchmark for its pledge at a 2009 United Nations summit in Copenhagen to reduce emissions 25 percent. Beginning in 2012, Japan placed a carbon tax based on emissions of fossil fuels, with the proceeds going to renewable energy and energy-saving projects.

    2013 CO2 emissions: 1.4 billion tons

    2013 population: 127 million

    GERMANY

    6
    In this picture taken Thursday, April 3, 2014, giant machines dig for brown coal at the open-cast mining Garzweiler near the city of Grevenbroich, western Germany. (AP Photo/Martin Meissner)

    It has outperformed the 21 percent reduction in greenhouse gases it agreed to in 1997. Emissions are down 25 percent against 1990 levels. To comply with 2020 European Union-set goals, Germany must reduce greenhouse gases 40 percent by 2020. On Wednesday, it boosted subsidies for energy efficiency to help it get there. Germany has in recent years seen back-to-back emissions increases due to higher demand for electricity and a switch to coal after Fukushima, which prompted a nuclear power phase-out. Coal use is down this year and renewables continue to gain electricity market share. Renewables already account for a quarter of Germany’s electrical production. The country plans to boost that share to 80 percent by 2050 — and put a million electric cars on the road by 2020.

    2013 CO2 emissions: 836 million tons

    2013 population: 80.6 million

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  • richardmitnick 2:14 pm on November 22, 2014 Permalink | Reply
    Tags: , Carbon studies,   

    Johns Hopkins University: “Deep-Earth Carbon Offers Clues About Origin of Life on Earth” 

    Johns Hopkins
    Johns Hopkins University

    Nov. 20, 2014
    Jill Rosen
    Office: 443-997-9906
    Cell: 443-547-8805
    jrosen@jhu.edu

    A Johns Hopkins-led team links new organic carbon species in deep fluids to the formation of diamonds — and life itself.

    New findings by a Johns Hopkins University-led team reveal long unknown details about carbon deep beneath the Earth’s surface and suggest ways this subterranean carbon might have influenced the history of life on the planet.

    The team also developed a new, related theory about how diamonds form in the Earth’s mantle.

    For decades scientists had little understanding of how carbon behaved deep below the Earth’s surface even as they learned more and more about the element’s vital role at the planet’s crust. Using a model created by Johns Hopkins geochemist Dimitri Sverjensky, Sverjensky, Vincenzo Stagno of the Carnegie Institution of Washington and Fang Huang, a Johns Hopkins graduate student, became the first to calculate how much carbon and what types of carbon exist in fluids at 100 miles below the Earth’s surface at temperatures up to 2,100 degrees F.

    ds
    Dimitri Sverjensky

    In an article published this week in the journal Nature Geoscience, Sverjensky and his team demonstrate that in addition to the carbon dioxide and methane already documented deep in subduction zones, there exists a rich variety of organic carbon species that could spark the formation of diamonds and perhaps even become food for microbial life.

    “It is a very exciting possibility that these deep fluids might transport building blocks for life into the shallow Earth,” said Sverjensky, a professor in the Department of Earth and Planetary Sciences. “This may be a key to the origin of life itself.”

    Sverjensky’s theoretical model, called the Deep Earth Water model, allowed the team to determine the chemical makeup of fluids in the Earth’s mantle, expelled from descending tectonic plates. Some of the fluids, those in equilibrium with mantle peridotite minerals, contained the expected carbon dioxide and methane. But others, those in equilibrium with diamonds and eclogitic minerals, contained dissolved organic carbon species including a vinegar-like acetic acid.

    These high concentrations of dissolved carbon species, previously unknown at great depth in the Earth, suggest they are helping to ferry large amounts of carbon from the subduction zone into the overlying mantle wedge where they are likely to alter the mantle and affect the cycling of elements back into the Earth’s atmosphere.

    The team also suggested that these mantle fluids with dissolved organic carbon species could be creating diamonds in a previously unknown way. Scientists have long believed diamond formation resulted through chemical reactions starting with either carbon dioxide or methane. The organic species offer a range of different starting materials, and an entirely new take on the creation of the gemstones.

    The research is part of a 10-year global project to further understanding of carbon on Earth called the Deep Carbon Observatory. The work is funded by the Alfred P. Sloan Foundation.

    See the full article here.

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    The Johns Hopkins University opened in 1876, with the inauguration of its first president, Daniel Coit Gilman. “What are we aiming at?” Gilman asked in his installation address. “The encouragement of research … and the advancement of individual scholars, who by their excellence will advance the sciences they pursue, and the society where they dwell.”

    The mission laid out by Gilman remains the university’s mission today, summed up in a simple but powerful restatement of Gilman’s own words: “Knowledge for the world.”

    What Gilman created was a research university, dedicated to advancing both students’ knowledge and the state of human knowledge through research and scholarship. Gilman believed that teaching and research are interdependent, that success in one depends on success in the other. A modern university, he believed, must do both well. The realization of Gilman’s philosophy at Johns Hopkins, and at other institutions that later attracted Johns Hopkins-trained scholars, revolutionized higher education in America, leading to the research university system as it exists today.

     
  • richardmitnick 4:27 pm on November 17, 2014 Permalink | Reply
    Tags: , Carbon studies, , ,   

    From LBL: “As Temperatures Rise, Soil Will Relinquish Less Carbon to the Atmosphere Than Currently Predicted” 

    Berkeley Logo

    Berkeley Lab

    November 17, 2014
    Dan Krotz 510-486-4019

    New Berkeley Lab model quantifies interactions between soil microbes and their surroundings

    Here’s another reason to pay close attention to microbes: Current climate models probably overestimate the amount of carbon that will be released from soil into the atmosphere as global temperatures rise, according to research from the US Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab).

    The findings are from a new computer model that explores the feedbacks between soil carbon and climate change. It’s the first such model to include several physiologically realistic representations of how soil microbes break down organic matter, a process that annually unleashes about ten times as much carbon into the atmosphere as fossil fuel emissions. In contrast, today’s models include a simplistic representation of microbial behavior.

    The research is published Nov. 17 on the website of the journal Nature Climate Change.

    Based on their results, the Berkeley Lab scientists recommend that future Earth system models include a more nuanced and dynamic depiction of how soil microbes go about the business of degrading organic matter and freeing up carbon.

    This approach could help scientists more accurately predict what will happen to soil carbon as Earth’s climate changes. These predictions are especially important in vulnerable regions like the Arctic, which is expected to warm considerably this century, and which holds a vast amount of carbon in the tundra.

    “We know that microbes are the agents of change when it comes to decomposing organic matter. But the question is: How important is it to explicitly quantify complex microbial interactions in climate models?” says Jinyun Tang, a scientist in Berkeley Lab’s Earth Sciences Division who conducted the research with fellow Berkeley Lab scientist William Riley.

    “We found that it makes a big difference,” Tang says. ”We showed that warming temperatures would return less soil carbon to the atmosphere than current models predict.”

    mod
    The complex and dynamic livelihood of soil microbes is captured in this schematic. For the first time, these processes are represented in a computer model that predicts the fate of soil carbon as temperatures rise. (Credit: Berkeley Lab)

    Terrestrial ecosystems, such as the Arctic tundra and Amazon rainforest, contain a huge amount of carbon in organic matter such as decaying plant material. Thanks to soil microbes that break down organic matter, these ecosystems also contribute a huge amount of carbon to the atmosphere.

    al
    The soil above the Arctic Circle near Barrow, Alaska contains a tremendous amount of carbon. New research may help scientists better predict how much of this carbon will be released as the climate warms.

    Because soil is such a major player in the carbon cycle, even a small change in the amount of carbon it releases can have a big affect on atmospheric carbon concentrations. This dynamic implies that climate models should represent soil-carbon processes as accurately as possible.

    But here’s the problem: Numerous empirical experiments have shown that the ways in which soil microbes decompose organic matter, and respond to changes in temperature, vary over time and from place to place. This variability is not captured in today’s ecosystem models, however. Microbes are depicted statically. They respond instantaneously when they’re perturbed, and then revert back as if nothing happened.

    To better portray the variability of the microbial world, Tang and Riley developed a numerical model that quantifies the costs incurred by microbes to respire, grow, and consume energy. Their model accounts for internal physiology, such as the production of enzymes that help microbes break down organic matter. It includes external processes, such as the competition for these enzymes once they’re outside the microbe. Some enzymes adsorb onto mineral surfaces, which means they are not available to chew through organic matter. The model also includes competition between different microbial populations.

    Together, these interactions—from enzymes to minerals to populations­—represent microbial networks as ever-changing systems, much like what’s observed in experiments.

    The result? When the model was subjected to a 4 degrees Celsius change, it predicted more variable but weaker soil-carbon and climate feedbacks than current approaches.

    “There’s less carbon flux to the atmosphere in response to warming,” says Riley. “Our representation is more complex, which has benefits in that it’s likely more accurate. But it also has costs, in that the parameters used in the model need to be further studied and quantified.”

    Tang and Riley recommend more research be conducted on these microbial and mineral interactions. They also recommend that these features ultimately be included in next-generation Earth system models, such as the Department of Energy’s Accelerated Climate Modeling for Energy, or ACME.

    The research was supported by the Department of Energy’s Office of Science.

    See the full article here.

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  • richardmitnick 1:30 pm on September 4, 2014 Permalink | Reply
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    From PNNL: “Birth of a mineral” 


    PNNL Lab

    September 04, 2014
    Mary Beckman, PNNL, (509) 375-3688

    One of the most important molecules on earth, calcium carbonate crystallizes into chalk, shells and minerals the world over. In a study led by the Department of Energy’s Pacific Northwest National Laboratory, researchers used a powerful microscope that allows them to see the birth of crystals in real time, giving them a peek at how different calcium carbonate crystals form, they report September 5 in Science.

    The results might help scientists understand how to lock carbon dioxide out of the atmosphere as well as how to better reconstruct ancient climates.

    “Carbonates are most important for what they represent, interactions between biology and Earth,” said lead researcher James De Yoreo, a materials scientist at PNNL. “For a decade, we’ve been studying the formation pathways of carbonates using high-powered microscopes, but we hadn’t had the tools to watch the crystals form in real time. Now we know the pathways are far more complicated than envisioned in the models established in the twentieth century.”

    Earth’s Reserve

    Calcium carbonate is the largest reservoir of carbon on the planet. It is found in rocks the world over, shells of both land- and water-dwelling creatures, and pearls, coral, marble and limestone. When carbon resides within calcium carbonate, it is not hanging out in the atmosphere as carbon dioxide, warming the world. Understanding how calcium carbonate turns into various minerals could help scientists control its formation to keep carbon dioxide from getting into the atmosphere.

    Calcium carbonate deposits also contain a record of Earth’s history. Researchers reconstructing ancient climates delve into the mineral for a record of temperature and atmospheric composition, environmental conditions and the state of the ocean at the time those minerals formed. A better understanding of its formation pathways will likely provide insights into those events.

    To get a handle on mineral formation, researchers at PNNL, the University of California, Berkeley, and Lawrence Berkeley National Laboratory [LBNL] examined the earliest step to becoming a mineral, called nucleation. In nucleation, molecules assemble into a tiny crystal that then grows with great speed. Nucleation has been difficult to study because it happens suddenly and unpredictably, so the scientists needed a microscope that could watch the process in real time.

    Come to Order

    In the 20th century, researchers established a theory that crystals formed in an orderly fashion. Once the ordered nucleus formed, more molecules added to the crystal, growing the mineral but not changing its structure. Recently, however, scientists have wondered if the process might be more complicated, with other things contributing to mineral formation. For example, in previous experiments they’ve seen forms of calcium carbonate that appear to be dense liquids that could be sources for minerals.

    Researchers have also wondered if calcite forms from less stable varieties or directly from calcium and carbonate dissolved in the liquid. Aragonite and vaterite are calcium carbonate minerals with slightly different crystal architectures than calcite and could represent a step in calcite’s formation. The fourth form called amorphous calcium carbonate — or ACC, which could be liquid or solid, might also be a reservoir for sprouting minerals.

    To find out, the team created a miniature lab under a transmission electron microscope at the Molecular Foundry, a DOE Office of Science User Facility at LBNL. In this miniature lab, they mixed sodium bicarbonate (used to make club soda) and calcium chloride (similar to table salt) in water. At high enough concentrations, crystals grew. Videos of nucleating and growing crystals recorded what happened:

    tem
    transmission electron microscope at LBNL

    Morphing Minerals

    The videos revealed that mineral growth took many pathways. Some crystals formed through a two-step process. For example, droplet-like particles of ACC formed, then crystals of aragonite or vaterite appeared on the surface of the droplets. As the new crystals formed, they consumed the calcium carbonate within the drop on which they nucleated.

    Other crystals formed directly from the solution, appearing by themselves far away from any ACC particles. Multiple forms often nucleated in a single experiment — at least one calcite crystal formed on top of an aragonite crystal while vaterite crystals grew nearby.

    What the team didn’t see in and among the many options, however, was calcite forming from ACC even though researchers widely expect it to happen. Whether that means it never does, De Yoreo can’t say for certain. But after looking at hundreds of nucleation events, he said it is a very unlikely event.

    “This is the first time we have directly visualized the formation process,” said De Yoreo. “We observed many pathways happening simultaneously. And they happened randomly. We were never able to predict what was going to come up next. In order to control the process, we’d need to introduce some kind of template that can direct which crystal forms and where.”

    In future work, De Yoreo and colleagues plan to investigate how living organisms control the nucleation process to build their shells and pearls. Biological organisms keep a store of mineral components in their cells and have evolved ways to make nucleation happen when and where needed. The team is curious to know how they use cellular molecules to achieve this control.

    This work was supported by the Department of Energy Office of Science.

    See the full article here.

    Pacific Northwest National Laboratory (PNNL) is one of the United States Department of Energy National Laboratories, managed by the Department of Energy’s Office of Science. The main campus of the laboratory is in Richland, Washington.

    PNNL scientists conduct basic and applied research and development to strengthen U.S. scientific foundations for fundamental research and innovation; prevent and counter acts of terrorism through applied research in information analysis, cyber security, and the nonproliferation of weapons of mass destruction; increase the U.S. energy capacity and reduce dependence on imported oil; and reduce the effects of human activity on the environment. PNNL has been operated by Battelle Memorial Institute since 1965.

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  • richardmitnick 5:50 pm on August 11, 2014 Permalink | Reply
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    From NASA/JPL at Caltech: “NASA Carbon Counter Reaches Final Orbit, Returns Data” 

    JPL

    August 11, 2014
    Alan Buis
    Jet Propulsion Laboratory, Pasadena, California
    818-354-0474
    alan.buis@jpl.nasa.gov

    Steve Cole
    NASA Headquarters, Washington
    202-358-0918
    stephen.e.cole@nasa.gov

    Just over a month after launch, the Orbiting Carbon Observatory-2 (OCO-2) — NASA’s first spacecraft dedicated to studying atmospheric carbon dioxide — has maneuvered into its final operating orbit and produced its first science data, confirming the health of its science instrument.

    NASA OCO satellite
    NASA OCO

    Atmospheric carbon dioxide is the leading human-produced greenhouse gas responsible for warming our world. It is a critical natural component of Earth’s carbon cycle. OCO-2 will produce the most detailed picture to date of sources of carbon dioxide, as well as their natural “sinks” — places on Earth’s surface where carbon dioxide is removed from the atmosphere. The observatory will study how these sources and sinks are distributed around the globe and how they change over time.

    Following launch from California’s Vandenberg Air Force Base on July 2, OCO-2 underwent a series of steps to configure the observatory for in-flight operations. Mission controllers established two-way communications with the observatory, stabilized its orientation in space and deployed its solar arrays to provide electrical power. The OCO-2 team then performed a checkout of OCO-2’s systems to ensure they were functioning properly.

    Through the month of July, a series of propulsive burns was executed to maneuver the observatory into its final 438-mile (705-kilometer), near-polar orbit at the head of the international Afternoon Constellation, or “A-Train,” of Earth-observing satellites. It arrived there on Aug. 3. Operations are now being conducted with the observatory in an orbit that crosses the equator at 1:36 p.m. local time.

    The A-Train, the first multi-satellite, formation-flying “super observatory” to record the health of Earth’s atmosphere and surface environment, collects an unprecedented quantity of nearly simultaneous climate and weather measurements. OCO-2 is now followed by the Japanese GCOM-W1 satellite, and then by NASA’s Aqua, CALIPSO, CloudSat and Aura spacecraft, respectively — all of which fly over the same point on Earth within 16 minutes of each other.

    With OCO-2 in its final orbit, mission controllers began cooling the observatory’s three-spectrometer instrument to its operating temperatures. The spectrometer’s optical components must be cooled to near 21 degrees Fahrenheit (minus 6 degrees Celsius) to bring them into focus and limit the amount of heat they radiate. The instrument’s detectors must be even cooler, near minus 243 degrees Fahrenheit (minus 153 degrees Celsius), to maximize their sensitivity.

    With the instrument’s optical system and detectors near their stable operating temperatures, the OCO-2 team collected “first light” test data on Aug. 6 as the observatory flew over central Papua New Guinea. The data were transmitted from OCO-2 to a ground station in Alaska, then to NASA’s Goddard Space Flight Center in Greenbelt, Maryland, for initial decoding, and then to NASA’s Jet Propulsion Laboratory in Pasadena, California, for further processing. The test provided the OCO-2 team with its first opportunity to see whether the instrument had reached orbit with the same performance it had demonstrated before launch.

    As OCO-2 flies over Earth’s sunlit hemisphere, each spectrometer collects a “frame” three times each second, for a total of about 9,000 frames from each orbit. Each frame is divided into eight spectra, or chemical signatures, that record the amount of molecular oxygen or carbon dioxide over adjacent ground footprints. Each footprint is about 1.3 miles (2.25 kilometers) long and a few hundred yards (meters) wide. When displayed as an image, the eight spectra appear like bar codes — bright bands of light broken by sharp dark lines. The dark lines indicate absorption by molecular oxygen or carbon dioxide.

    “The initial data from OCO-2 appear exactly as expected — the spectral lines are well resolved, sharp and deep,” said OCO-2 chief architect and calibration lead Randy Pollock of JPL. “We still have a lot of work to do to go from having a working instrument to having a well-calibrated and scientifically useful instrument, but this was an important milestone on this journey.”

    Over the next several weeks, the OCO-2 team will conduct a series of calibration activities to characterize fully the performance of the instrument and observatory. In parallel, OCO-2 will routinely record and return up to 1 million science observations each day. These data will be used initially to test the ground processing system and verify its products. The team will begin delivering calibrated OCO-2 spectra data to NASA’s Goddard Earth Sciences Data and Information Services Center for distribution to the global science community and other interested parties before the end of the year. The team will also deliver estimates of carbon dioxide to that same center for distribution in early 2015.

    OCO-2 is a NASA Earth System Science Pathfinder Program mission managed by JPL for NASA’s Science Mission Directorate in Washington. Orbital Sciences Corporation in Dulles, Virginia, built the spacecraft bus and provides mission operations under JPL’s leadership. The science instrument was built by JPL, based on the instrument design co-developed for the original OCO mission by Hamilton Sundstrand in Pomona, California. NASA’s Launch Services Program at NASA’s Kennedy Space Center in Florida was responsible for launch management.

    NASA monitors Earth’s vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

    See the full article here.

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 9:32 am on August 7, 2014 Permalink | Reply
    Tags: , Carbon studies, ,   

    From physicsworld.com: “Molecular seeds sprout identical carbon nanotubes” 

    physicsworld
    physicsworld.com

    Aug 7, 2014
    Hamish Johnston

    The first effective technique for growing a batch of single-walled carbon nanotubes (SWCNTs) that all have the same molecular structure has been developed by scientists in Switzerland. The new process involves using “seed molecules” on a platinum substrate to grow SWCNTs with the desired structure. The breakthrough could be extremely important to those developing electronic devices based on SWCNTs because nanotubes with different structures can have very different electronic properties.

    tube
    Up, up and away: growing a nanotube from a seed molecule

    An SWCNT can be thought of as an atomically thin sheet of carbon that has been rolled up to form a tube about 1 nm thick, resembling a drinking straw. The carbon sheet always has the same honeycomb structure, which it shares with graphene. However, there are about a hundred different ways that the edges of the sheet can join together to make a tube, and this defines whether an SWCNT conducts electricity like a metal or a semiconductor. In the case of semiconducting nanotubes, the size of the electronic band gap also depends on how the edges are joined.

    Electronic devices based on SWCNTs could, in principle, be used to create transistors and other components that are smaller, faster and more energy efficient than those based on silicon. But before that can happen, scientists have to come up with reliable ways of producing batches of SWCNTs with identical structures.
    Costly separation

    Careful control of how SWCNTs are prepared can limit the number of different structures to as few as five. Then SWCNTs with the desired structure can be separated from a mixture. However, this is a very costly process with a structurally pure sample of SWCNTs costing about $1000 per milligram from a chemical supplier. As a result, scientists are very keen on developing methods for producing batches containing just one structure.

    This latest work was done by Juan Ramon Sanchez-Valencia and colleagues at the Swiss Federal Laboratories for Material Sciences and Technology (Empa) in Zürich.

    grow
    Grown from seed

    The new technique is based on the fact that, unlike a drinking straw, the tips of SWCNTs are capped by carbon atoms and each species has a cap with a different structure. The team used the established technique of organic chemical synthesis to create cap molecules with the same structure as the cap of the desired structural species of SWCNT. These cap molecules are placed on a platinum surface, which is heated in the presence of a carbon-rich gas such as ethylene. The platinum surface acts as a catalyst, pulling carbon atoms from the gas and passing them to the cap molecules. This steady supply of carbon molecules attaches itself to the bottom of a cap and pushes it up from surface, creating an SWCNT with the desired structure.

    Metallic armchairs

    The cap molecules were designed to seed SWCNTs with the “(6,6) armchair” structure. This much-studied type of nanotube is of interest to device designers because it conducts electricity like a metal. The SWCNTs were grown to several hundred nanometres in length before they were analysed using scanning tunnelling microscopy (STM) and Raman spectroscopy. This revealed that the SWCNTS were all of the same type and were free of structural defects.

    “The clever thing about this is that they predesign the cap and that cap then defines the nanotube type,” explains SWCNT expert James Tour at Rice University in the US, who was not involved in the research. Although the team did not show that the technique can create other types of SWCNTs by using different cap molecules, Tour says that this possibility “seems to be implied and it is likely that that would be the case”.

    Making tonnes of nanotubes

    An important benefit of the new technique is that 1 kg of seed molecules could, in principle, produce 5 tonnes of SWCNTs, each 10 μm in length. On the downside, a platinum surface measuring about 30 km2 would be needed to grow such a quantity of SWCNTs.

    An additional challenge facing anyone wanting to use the technique to produce commercial quantities of SWCNTs is how to deal with the entanglement of neighbouring nanotubes. This occurs before the SWCNTs reach a usable length, and disentangling nanotubes can be a tricky process.

    The new technique is described in Nature.

    See the full article here.

    PhysicsWorld is a publication of the Institute of Physics. The Institute of Physics is a leading scientific society. We are a charitable organisation with a worldwide membership of more than 50,000, working together to advance physics education, research and application.

    We engage with policymakers and the general public to develop awareness and understanding of the value of physics and, through IOP Publishing, we are world leaders in professional scientific communications.
    IOP Institute of Physics

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  • richardmitnick 12:57 pm on July 9, 2014 Permalink | Reply
    Tags: , Carbon studies, ,   

    From physicsworld.com: “Carbon nucleus seen spinning in triangular state” 

    physicsworld
    physicsworld.com

    Jul 8, 2014
    Hamish Johnston

    Physicists have obtained important new evidence showing that the structure of the carbon-12 nucleus – without which there would be no life here on Earth – resembles that of an equilateral triangle. The evidence was obtained by physicists in the UK, Mexico and the US by measuring a new rapidly spinning rotational state of the nucleus. The finding suggests that the “Hoyle state” of carbon-12, which plays an important role in the creation of carbon in red giant stars, has the same shape too. Recent theoretical predictions, in contrast, had suggested that the Hoyle state is more like an obtuse triangle or “bent arm”.

    All the carbon in the universe is created in red giant stars by two alpha particles (helium-4 nuclei) fusing to create a short-lived beryllium-8 nucleus, which then captures a third alpha particle to form carbon-12. But exactly how this reaction occurs initially puzzled physicists, whose early understanding of carbon-12 suggested that it would proceed much too slowly to account for the known abundance of carbon in the universe. Then in 1954 the British astronomer Fred Hoyle predicted that carbon-12 had a hitherto unknown excited state – now dubbed the Hoyle state – which boosts the rate of carbon-12 production.

    Three years later the Hoyle state was confirmed experimentally by physicists working at Caltech. However, the precise arrangement of the protons and neutrons in the carbon-12 nucleus remains a matter of much debate. While some physicists feel that carbon-12 is best thought of as 12 interacting nucleons, others believe that the nucleus can be modelled as three alpha particles that are bound together. The rational for the latter model is that alpha particles are extremely stable and so are likely to endure within the carbon-12 nucleus.
    Molecular inspiration

    If carbon-12 is indeed well described as three alpha particles, molecular physics could provide important clues about how those particles are arranged. In 2000 Roelof Bijker of the National Autonomous University of Mexico (UNAM) and Francesco Iachello at Yale University suggested that the three alpha particles could arrange themselves in an equilateral triangle in which the three alpha particles are all in the same plane. Such a structure had already been spotted five years earlier in the triatomic hydrogen molecular ion, H3+.

    Now, Bijker has joined forces with Martin Freer and colleagues at the University of Birmingham and Moshe Gai at the University of Connecticut to obtain the best experimental evidence so far that carbon-12 is indeed shaped like an equilateral triangle. The experiment was carried out at Birmingham’s cyclotron by firing a beam of alpha particles at a carbon target to produce carbon-12 nuclei that are in high spin states. Indeed, the nuclei, which literally spin like tops, are rotating so fast that they tear apart by emitting alpha particles.

    man
    The University of Birmingham’s cyclotron

    By measuring the energy and angular distribution of the alpha particles, the team observed a high spin state that had never been seen before. When analysed along with four lower spin states measured in previous experiments, the new data suggest very strongly that the carbon-12 nucleus resembles an equilateral triangle that has been set spinning like a three-pointed pinwheel.

    Breathing nucleus

    This description applies to the ground-state rotational band of carbon-12, but it also has significance for the Hoyle state. This is because the spectrum of the Hoyle-state rotational band appears to be similar to that of the ground-state band – with two of the five spin states measured already. However, the Hoyle state appears to have a larger moment of inertia than the ground state. This suggests that the Hoyle state is a “breathing mode” whereby the equilateral triangle expands. This expanded nucleus can itself be set spinning, resulting in a series of excited states similar to that of the ground-state band of carbon-12.

    This evidence pointing towards an equilateral-triangle-shaped Hoyle state appears to be at odds with the recent calculations that suggested that it is more like an obtuse triangle. However, alpha-decay measurements do not give physicists the complete picture of the shape of a nucleus and the only way to be sure of the structure is to study the gamma rays that are given off when a spin state decays. While such studies are commonplace in nuclear physics, they are much harder for carbon-12 because the nucleus is much more likely to decay by emitting an alpha particle than a gamma ray.

    Freer and colleagues are now, however, developing an experiment that will try to capture the gamma rays given off by the spinning carbon-12 nuclei and hope to be making measurements before the end of this year. So 60 years after the Hoyle state was predicted, we may finally know its shape.

    The research is described in Physical Review Letters.

    See the full article here.

    PhysicsWorld is a publication of the Institute of Physics. The Institute of Physics is a leading scientific society. We are a charitable organisation with a worldwide membership of more than 50,000, working together to advance physics education, research and application.

    We engage with policymakers and the general public to develop awareness and understanding of the value of physics and, through IOP Publishing, we are world leaders in professional scientific communications.
    IOP Institute of Physics


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