131 research outputs found

    Robert A. Arnone

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    Robert Arnone\u27s expertise is in the coupling biological optical and physical processes using ocean color satellite combined with ocean models. He has developed bio-optical algorithms from satellites and applied to ecological forecasting models using data assimilation from ship and gliders. He has developed new at sea optical instrumentation for measuring optical properties of ocean waters. Robert Arnone leads the National Ocean calibration and validation efforts for the Joint Polar Satellite System for NOAA, NASA, and Navy the NPP satellite ocean calibration and validation team with NOAA and university for SST and ocean color. He managed NRL’s Hyperspectral satellite Hyperspectral Imaging of the Coastal Environment (HICO) which was successfully launched to the International Space Station (Aug 2009). He serves on science teams for NASA, NOAA, EPA and Navy for developing future satellite systems and for establishing policy for ocean and coastal research (MODIS, SeaWIFS, VIIRS, GEOCAPE ,HICO). He has over 120 scientific publications and \u3e250 presentations in the areas of physical and bio-optical ocean processes. He has lead over 15 major national and international scientific oceanographic expeditions in the world oceans including Arabian Sea, Mediterranean, Japan East Sea, Iceland Greenland, and Gulf Stream . He has received awards for honors for “science to operations” transitions and NRL publication awards 1998 , 2002, 2008. He has received 2 Navy patents and NASA honors for astronaut training programs. He has received awards for Navy Meritorious Civilian Service Award ; US Dept of Navy - honors, and; NASA - honors for Shuttle Astronaut Training program, Navy Royalty Transition award. Her has served on graduate student committees at USM, RSMAS, and University of Southern Alabama. Robert Arnone retired from the Navy Research Laboratory as head of the Ocean Science Branch

    Robert A. Arnone

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    Robert Arnone\u27s expertise is in the coupling biological optical and physical processes using ocean color satellite combined with ocean models. He has developed bio-optical algorithms from satellites and applied to ecological forecasting models using data assimilation from ship and gliders. He has developed new at sea optical instrumentation for measuring optical properties of ocean waters. Robert Arnone leads the National Ocean calibration and validation efforts for the Joint Polar Satellite System for NOAA, NASA, and Navy the NPP satellite ocean calibration and validation team with NOAA and university for SST and ocean color. He managed NRL’s Hyperspectral satellite Hyperspectral Imaging of the Coastal Environment (HICO) which was successfully launched to the International Space Station (Aug 2009). He serves on science teams for NASA, NOAA, EPA and Navy for developing future satellite systems and for establishing policy for ocean and coastal research (MODIS, SeaWIFS, VIIRS, GEOCAPE ,HICO). He has over 120 scientific publications and \u3e250 presentations in the areas of physical and bio-optical ocean processes. He has lead over 15 major national and international scientific oceanographic expeditions in the world oceans including Arabian Sea, Mediterranean, Japan East Sea, Iceland Greenland, and Gulf Stream . He has received awards for honors for “science to operations” transitions and NRL publication awards 1998 , 2002, 2008. He has received 2 Navy patents and NASA honors for astronaut training programs. He has received awards for Navy Meritorious Civilian Service Award ; US Dept of Navy - honors, and; NASA - honors for Shuttle Astronaut Training program, Navy Royalty Transition award. Her has served on graduate student committees at USM, RSMAS, and University of Southern Alabama. Robert Arnone retired from the Navy Research Laboratory as head of the Ocean Science Branch

    Thinking Outside of the Blue Marble: Novel Ocean Applications Using the VIIRS Sensor

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    While planning for future space-borne sensors will increase the quality, quantity, and duration of ocean observations in the years to come, efforts to extend the limits of sensors currently in orbit can help shed light on future scientific gains as well as associated uncertainties. Here, we present several applications that are unique to the polar orbiting Visual Infrared Imaging Radiometer Suite (VIIRS), each of which challenge the threshold capabilities of the sensor and provide lessons for future missions. For instance, while moderate resolution polar orbiters typically have a one day revisit time, we are able to obtain multiple looks of the same area by focusing on the extreme zenith angles where orbital views overlap, and pair these observations with those from other sensors to create pseudo-geostationary data sets. Or, by exploiting high spatial resolution (imaging) channels and analyzing patterns of synoptic covariance across the visible spectrum, we can obtain higher spatial resolution bio-optical products. Alternatively, non-traditional products can illuminate important biological interactions in the ocean, such as the use of the Day-Night-Band to provide some quantification of phototactic behavior of marine life along light polluted beaches, as well as track the location of marine fishing vessel fleets along ocean fronts. In this talk, we explore ways to take full advantage of the capabilities of existing sensors in order to maximize insights for future missions

    Investigation of advanced counterrotation blade configuration concepts for high speed turboprop systems. Task 5: Unsteady counterrotation ducted propfan analysis. Computer program user's manual

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    The primary objective of this study was the development of a time-marching three-dimensional Euler/Navier-Stokes aerodynamic analysis to predict steady and unsteady compressible transonic flows about ducted and unducted propfan propulsion systems employing multiple blade rows. The computer codes resulting from this study are referred to as ADPAC-AOACR (Advanced Ducted Propfan Analysis Codes-Angle of Attack Coupled Row). This report is intended to serve as a computer program user's manual for the ADPAC-AOACR codes developed under Task 5 of NASA Contract NAS3-25270, Unsteady Counterrotating Ducted Propfan Analysis. The ADPAC-AOACR program is based on a flexible multiple blocked grid discretization scheme permitting coupled 2-D/3-D mesh block solutions with application to a wide variety of geometries. For convenience, several standard mesh block structures are described for turbomachinery applications. Aerodynamic calculations are based on a four-stage Runge-Kutta time-marching finite volume solution technique with added numerical dissipation. Steady flow predictions are accelerated by a multigrid procedure. Numerical calculations are compared with experimental data for several test cases to demonstrate the utility of this approach for predicting the aerodynamics of modern turbomachinery configurations employing multiple blade rows

    The Impact of Coastal Phytoplankton Blooms on Ocean-Atmosphere Thermal Energy Exchange: Evidence From a Two-Way Coupled Numerical Modeling System

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    A set of sensitivity experiments are performed with a two-way coupled and nested ocean-atmosphere forecasting system in order to deconvolve how dense phytoplankton stocks in a coastal embayment may impact thermal energy exchange processes. Monterey Bay simulations parameterizing solar shortwave transparency in the surface ocean as an invariant oligotrophic oceanic water type estimate consistently colder sea surface temperature (SST) than simulations utilizing more realistic, spatially varying shortwave attenuation terms based on satellite estimates of surface algal pigment concentration. These SST differences lead to an similar to 88% increase in the cumulative turbulent thermal energy transfer from the ocean to the atmosphere over the three month simulation period. The result is a warmer simulated atmospheric boundary layer with respective local air temperature differences approaching similar to 2 degrees C. This study suggests that the retention of shortwave solar flux by ocean flora may directly impact even short-term forecasts of coastal meteorological variables. Citation: Jolliff, J. K., T. A. Smith, C. N. Barron, S. deRada, S. C. Anderson, R. W. Gould, and R. A. Arnone (2012), The impact of coastal phytoplankton blooms on ocean-atmosphere thermal energy exchange: Evidence from a two-way coupled numerical modeling system, Geophys. Res. Lett., 39, L24607, doi:10.1029/2012GL053634

    Resource limitation modulates the fate of dissimilated nitrogen in a dual-pathway Actinobacterium

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    Respiratory ammonification and denitrification are two evolutionarily unrelated dissimilatory nitrogen (N) processes central to the global N cycle, the activity of which is thought to be controlled by carbon (C) to nitrate (NO₃⁻) ratio. Here we find that Intrasporangium calvum C5, a novel menaquinone-based dual-pathway denitrifier/respiratory ammonifier, disproportionately utilizes ammonification rather than denitrification when grown under carbon or nitrate limitation, not C:NO3- ratio. Instead, C:NO₃⁻ ratio is a confounding variable for resource limitation. We find that the protein atomic composition for denitrification modules (NirK) are significantly cost minimized for C and N compared to ammonification modules (NrfA), indicating that resource limitation is a major selective pressure imprinted in the architecture of these proteins. The evolutionary precedent for these findings suggests ecological and biogeochemical importance as evidenced by higher growth rates when I. calvum grows predominantly using its ammonification pathway and by assimilating its end-product (ammonium) for growth under ammonium-deplete conditions. Genomic analysis of I. calvum further reveals a versatile ecophysiology to cope with nutrient stress and redox conditions. Metabolite and transcriptional profiles during growth indicate that transcript abundances encoding for its nitrite reducing enzyme modules, NrfAH and NirK, significantly increase in response to nitrite production. Mechanistically, our results suggest that pathway selection is driven by intracellular redox potential (redox poise), which may be lowered during resource limitation, thereby decreasing catalytic activity of upstream electron transport steps needed for denitrification enzymes. Our work advances our understanding of the biogeochemical flexibility of N-cycling organisms, pathway evolution, and ecological food-webs

    Optical scattering and backscattering by organic and inorganic particulates in U.S. coastal waters

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    We present the results of a study of optical scattering and backscattering of particulates for three coastal sites that represent a wide range of optical properties that are found in U.S. near-shore waters. The 6000 scattering and backscattering spectra collected for this study can be well approximated by a power-law function of wavelength. The power-law exponent for particulate scattering changes dramatically from site to site (and within each site) compared with particulate backscattering where all the spectra, except possibly the very clearest waters, cluster around a single wavelength power-law exponent of −0.94 . The particulate backscattering-to-scattering ratio (the backscattering ratio) displays a wide range in wavelength dependence. This result is not consistent with scattering models that describe the bulk composition of water as a uniform mix of homogeneous spherical particles with a Junge-like power-law distribution over all particle sizes. Simultaneous particulate organic matter (POM) and particulate inorganic matter (PIM) measurements are available for some of our optical measurements, and site-averaged POM and PIM mass-specific cross sections for scattering and backscattering can be derived. Cross sections for organic and inorganic material differ at each site, and the relative contribution of organic and inorganic material to scattering and backscattering depends differently at each site on the relative amount of material that is present

    Resource Concentration Modulates the Fate of Dissimilated Nitrogen in a Dual-Pathway Actinobacterium

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    Respiratory ammonification and denitrification are two evolutionarily unrelated dissimilatory nitrogen (N) processes central to the global N cycle, the activity of which is thought to be controlled by carbon (C) to nitrate (NO_3^−) ratio. Here we find that Intrasporangium calvum C5, a novel dual-pathway denitrifier/respiratory ammonifier, disproportionately utilizes ammonification rather than denitrification when grown under low C concentrations, even at low C:NO_3^− ratios. This finding is in conflict with the paradigm that high C:NO_3^− ratios promote ammonification and low C:NO_3^− ratios promote denitrification. We find that the protein atomic composition for denitrification modules (NirK) are significantly cost minimized for C and N compared to ammonification modules (NrfA), indicating that limitation for C and N is a major evolutionary selective pressure imprinted in the architecture of these proteins. The evolutionary precedent for these findings suggests ecological importance for microbial activity as evidenced by higher growth rates when I. calvum grows predominantly using its ammonification pathway and by assimilating its end-product (ammonium) for growth under ammonium-free conditions. Genomic analysis of I. calvumfurther reveals a versatile ecophysiology to cope with nutrient stress and redox conditions. Metabolite and transcriptional profiles during growth indicate that enzyme modules, NrfAH and NirK, are not constitutively expressed but rather induced by nitrite production via NarG. Mechanistically, our results suggest that pathway selection is driven by intracellular redox potential (redox poise), which may be lowered when resource concentrations are low, thereby decreasing catalytic activity of upstream electron transport steps (i.e., the bc1 complex) needed for denitrification enzymes. Our work advances our understanding of the biogeochemical flexibility of N-cycling organisms, pathway evolution, and ecological food-webs
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