Sample records for ice crystal number

  1. Effects of Pre-Existing Ice Crystals on Cirrus Clouds and Comparison between Different Ice Nucleation Parameterizations with the Community Atmosphere Model (CAM5)

    SciTech Connect (OSTI)

    Shi, Xiangjun; Liu, Xiaohong; Zhang, Kai

    2015-01-01T23:59:59.000Z

    In order to improve the treatment of ice nucleation in a more realistic manner in the Community Atmospheric Model version 5.3 (CAM5.3), the effects of preexisting ice crystals on ice nucleation in cirrus clouds are considered. In addition, by considering the in-cloud variability in ice saturation ratio, homogeneous nucleation takes place spatially only in a portion of cirrus cloud rather than in the whole area of cirrus cloud. With these improvements, the two unphysical limiters used in the representation of ice nucleation are removed. Compared to observations, the ice number concentrations and the probability distributions of ice number concentration are both improved with the updated treatment. The preexisting ice crystals significantly reduce ice number concentrations in cirrus clouds, especially at mid- to high latitudes in the upper troposphere (by a factor of ~10). Furthermore, the contribution of heterogeneous ice nucleation to cirrus ice crystal number increases considerably.Besides the default ice nucleation parameterization of Liu and Penner (2005, hereafter LP) in CAM5.3, two other ice nucleation parameterizations of Barahona and Nenes (2009, hereafter BN) and Kärcher et al. (2006, hereafter KL) are implemented in CAM5.3 for the comparison. In-cloud ice crystal number concentration, percentage contribution from heterogeneous ice nucleation to total ice crystal number, and preexisting ice effects simulated by the three ice nucleation parameterizations have similar patterns in the simulations with present-day aerosol emissions. However, the change (present-day minus pre-industrial times) in global annual mean column ice number concentration from the KL parameterization (3.24×106 m-2) is obviously less than that from the LP (8.46×106 m-2) and BN (5.62×106 m-2) parameterizations. As a result, experiment using the KL parameterization predicts a much smaller anthropogenic aerosol longwave indirect forcing (0.24 W m-2) than that using the LP (0.46 W m-2) and BN (0.39 W m-2) parameterizations.

  2. The effect of ice crystal surface roughness on the retrieval of ice cloud microphysical and optical properties

    E-Print Network [OSTI]

    Xie, Yu

    2007-09-17T23:59:59.000Z

    The effect of the surface roughness of ice crystals is not routinely accounted for in current cloud retrieval algorithms that are based on pre-computed lookup libraries. In this study, we investigate the effect of ice crystal surface roughness...

  3. Scattering Properties of Oriented Hexagonal Ice Crystals

    E-Print Network [OSTI]

    Zhang, Feng

    2010-01-14T23:59:59.000Z

    To interpret the data from spaceborn lidar measurements, one must have a basic understanding of the backscattering of oriented ice particles. The conventional raytracing method is not applicable to the scattering of light by oriented particles...

  4. Computation of the scattering properties of nonspherical ice crystals

    E-Print Network [OSTI]

    Zhang, Zhibo

    2004-11-15T23:59:59.000Z

    This thesis is made up of three parts on the computation of scattering properties of nonspherical particles in the atmosphere. In the first part, a new crystal type-droxtal-is introduced to make a better representation of the shape of small ice...

  5. Theoretical investigation of the collection of aerosol particles by falling ice crystals

    SciTech Connect (OSTI)

    Miller, N.L.

    1987-01-01T23:59:59.000Z

    A numerical scheme that determines the collection efficiencies, kernels, and washout rates of aerosol particles (APs) by falling columnar and plate-like ice crystals is presented. A theoretical model for the removal of micron-size APs by falling columnar ice crystals which incorporates gravitational, inertial, thermophoretic, diffusiophoretic and electrostatic forcing has been formulated. This trajectory model which includes computed velocity, temperature and water vapor density fields, was coupled to a flux model which determines the removal of submicron particles due to Brownian diffusion, thermo and diffusio-phoresis as well as electrostatic forcing. This combined model indicates collection efficiencies for APs of radii 0.001 to 10.0 ..mu..m for the columnar ice crystal size distribution. An earlier study provides AP collection efficiencies by ice crystal plates for the ice crystal plate size distribution. The columnar ice crystal-AP collection model indicates that efficiency increases with increasing pressure, temperature or electrostatic charge for decreasing relative humidity.

  6. Parameterization of the scattering and absorption properties of individual ice crystals

    SciTech Connect (OSTI)

    Yang, Ping [Department of Atmospheric Sciences, University of California, Los Angeles (United States)] [Department of Atmospheric Sciences, University of California, Los Angeles (United States); Liou, K. N. [Department of Atmospheric Sciences, University of California, Los Angeles (United States)] [Department of Atmospheric Sciences, University of California, Los Angeles (United States); Wyser, Klaus [Department of Meteorology, Stockholm University, Stockholm (Sweden)] [Department of Meteorology, Stockholm University, Stockholm (Sweden); Mitchell, David [Atmospheric Sciences Center, Desert Research Institute, Reno, Nevada (United States)] [Atmospheric Sciences Center, Desert Research Institute, Reno, Nevada (United States)

    2000-02-27T23:59:59.000Z

    We present parameterizations of the single-scattering properties for individual ice crystals of various habits based on the results computed from the accurate light scattering calculations. The projected area, volume, and single-scattering properties of ice crystals with various shapes and sizes are computed for 56 narrow spectral bands covering 0.2-5 {mu}m. The ice crystal habits considered in this study are hexagonal plates, solid and hollow columns, planar and spatial bullet rosette, and aggregates that are commonly observed in cirrus clouds. Using the observational relationships between the aspect ratios and the sizes of ice crystals, we can define the three-dimensional structure of these ice crystal habits with respect to their maximum dimensions for light scattering calculations. The volume and projected area of ice crystals, expressed in terms of the diameters of the corresponding equivalent spheres, are first parameterized by employing the ice crystal maximum dimensions. Further, various analytical expressions as functions of the effective dimensions of ice crystals have been developed to parameterize the extinction and absorption efficiencies, asymmetry factor, and the truncation of the forward peak energy in the phase function. The present parameterization scheme provides an efficient approach to obtain the basic scattering and absorption properties of nonspherical ice crystals. (c) 2000 American Geophysical Union.

  7. Isothermal Ice-Crystallization Kinetics in the Gas-Diffusion Layer of a Proton-Exchange-Membrane Fuel Cell

    E-Print Network [OSTI]

    Dursch, Thomas J.

    2013-01-01T23:59:59.000Z

    l water O oxidized carbon s ice T PTFE dry dry gas-diffusioncrystallization) to form 99% of ice using eq 10 with k T (of California. Isothermal Ice-Crystallization Kinetics in

  8. OTC Paper Number 24645 GPU-Event-Mechanics Evaluation of Ice Impact Load Statistics

    E-Print Network [OSTI]

    Peters, Dennis

    OTC Paper Number 24645 GPU-Event-Mechanics Evaluation of Ice Impact Load Statistics Claude Daley of a GPU-Event-Mechanics (GEM) simulation to assess local ice loads on a vessel operating in pack ice workstation. The simulation domain contains hundreds of discrete and interacting ice floes. A simple vessel

  9. Light Scattering by Ice Crystals and Mineral Dust Aerosols in the Atmosphere

    E-Print Network [OSTI]

    Bi, Lei

    2012-07-16T23:59:59.000Z

    Modeling the single-scattering properties of nonspherical particles in the atmo¬sphere (in particular, ice crystals and dust aerosols) has important applications to climate and remote sensing studies. The ?rst part of the dissertation (Chapters II...

  10. An Investigation of Light Scattering by Irregular Ice Crystals via PSTD

    E-Print Network [OSTI]

    Zhang, Jianing

    2014-07-28T23:59:59.000Z

    to determine the validity PSTD with CPML. We propose a random field model for surface irregularities of ice crystals with roughened surfaces. Results using this model show that reflection probability decreases exponentially as the roughness is increased...

  11. Laboratory Investigation of Contact Freezing and the Aerosol to Ice Crystal Transformation Process

    SciTech Connect (OSTI)

    Shaw, Raymond A. [Michigan Technological University

    2014-10-28T23:59:59.000Z

    This project has been focused on the following objectives: 1. Investigations of the physical processes governing immersion versus contact nucleation, specifically surface-induced crystallization; 2. Development of a quadrupole particle trap with full thermodynamic control over the temperature range 0 to –40 °C and precisely controlled water vapor saturation ratios for continuous, single-particle measurement of the aerosol to ice crystal transformation process for realistic ice nuclei; 3. Understanding the role of ice nucleation in determining the microphysical properties of mixed-phase clouds, within a framework that allows bridging between laboratory and field measurements.

  12. Structural transformation in supercooled water controls the crystallization rate of ice

    E-Print Network [OSTI]

    Emily B. Moore; Valeria Molinero

    2011-09-27T23:59:59.000Z

    One of water's unsolved puzzles is the question of what determines the lowest temperature to which it can be cooled before freezing to ice. The supercooled liquid has been probed experimentally to near the homogeneous nucleation temperature TH{\\approx}232 K, yet the mechanism of ice crystallization - including the size and structure of critical nuclei - has not yet been resolved. The heat capacity and compressibility of liquid water anomalously increase upon moving into the supercooled region according to a power law that would diverge at Ts{\\approx}225 K,(1,2) so there may be a link between water's thermodynamic anomalies and the crystallization rate of ice. But probing this link is challenging because fast crystallization prevents experimental studies of the liquid below TH. And while atomistic studies have captured water crystallization(3), the computational costs involved have so far prevented an assessment of the rates and mechanism involved. Here we report coarse-grained molecular simulations with the mW water model(4) in the supercooled regime around TH, which reveal that a sharp increase in the fraction of four-coordinated molecules in supercooled liquid water explains its anomalous thermodynamics and also controls the rate and mechanism of ice formation. The simulations reveal that the crystallization rate of water reaches a maximum around 225 K, below which ice nuclei form faster than liquid water can equilibrate. This implies a lower limit of metastability of liquid water just below TH and well above its glass transition temperature Tg{\\approx}136 K. By providing a relationship between the structural transformation in liquid water, its anomalous thermodynamics and its crystallization rate, this work provides a microscopic foundation to the experimental finding that the thermodynamics of water determines the rates of homogeneous nucleation of ice.(5)

  13. Kinetics of Conversion of Air Bubbles to Air-Hydrate Crystals in Antarctic Ice

    E-Print Network [OSTI]

    P. B. Price

    1995-01-23T23:59:59.000Z

    The depth-dependence of bubble concentration at pressures above the transition to the air hydrate phase and the optical scattering length due to bubbles in deep ice at the South Pole are modeled using diffusion-growth data from the laboratory, taking into account the dependence of age and temperature on depth in the ice. The model fits the available data on bubbles in cores from Vostok and Byrd and on scattering length in deep ice at the South Pole. It explains why bubbles and air hydrate crystals co-exist in deep ice over a range of depths as great as 800 m and predicts that at depths below $\\rm \\sim$ 1400 m the AMANDA neutrino observatory at the South Pole will operate unimpaired by light scattering from bubbles.

  14. Paper No. ICETECH12-XYZ-R0 Daley Page number: 1 GPU Modeling of Ship Operations in Pack Ice

    E-Print Network [OSTI]

    Peters, Dennis

    Paper No. ICETECH12-XYZ-R0 Daley Page number: 1 GPU Modeling of Ship Operations in Pack Ice Claude The paper explores the use of an event-mechanics approach to assess vessel performance in pack ice of simulation domains, each containing hundreds of discrete and interacting ice floes is modeled. A simple

  15. VOLUME 88 NUMBER 19 8 MAY 2007 Methane hydrate is a clathrate, an ice-like

    E-Print Network [OSTI]

    Mazzini, Adriano

    ., 1999; Bouriak et al., 2000; Hovland and Svensen, 2006], the pres- ence of gas hydrate had never been are lined with hydrate and whether any free gas exists in the chimneys, and to provide evidence209 VOLUME 88 NUMBER 19 8 MAY 2007 Methane hydrate is a clathrate, an ice-like solid formed from

  16. Reflections on a record minimum The numbers are in 2012 broke the record for minimum sea ice extent and is still heading down (see

    E-Print Network [OSTI]

    in climate models. The approach was to freeze an icebreaker into the pack ice and drift for a year makingReflections on a record minimum The numbers are in ­ 2012 broke the record for minimum sea ice extent and is still heading down (see Figure 1). The sea ice extent data tell an unequivocal story of ice

  17. Ann. Geophysicae 14, 1192--1197 (1996) EGS --Springer-Verlag 1996 Pyramidal ice crystal scattering phase functions

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    tracing method for single hexagonal pyramidal ice crystals (such as solid and hollow bullets) randomly times since the beginning of this century, such as by Andrus (1915), Kimball (1915), Brush (1919), Leaf-tracing simulations for hexagonal hollow-ended column and bullet-rosette models, and con- cluded that the typical

  18. Simulation of the Extinction Efficiency, the Absorption Efficiency and the Asymmetry Factor of Ice Crystals and Relevant Applications to the Study of Cirrus Cloud Radiative Properties

    E-Print Network [OSTI]

    Lu, Kai

    2010-10-12T23:59:59.000Z

    The single-scattering properties of six non-spherical ice crystals, droxtals, plates, solid columns, hollow columns, aggregates and 6-branch bullet rosettes are simulated. The anomalous diffraction theory (ADT) is applied to the simulation...

  19. The effects of small ice crystals on the infrared radiative properties of cirrus clouds. Semiannual status report, 1 October 1989-31 March 1990

    SciTech Connect (OSTI)

    Takano, Y.; Liou, K.N.; Asano, S.; Heymsfield, A.; Minnis, P.

    1990-04-01T23:59:59.000Z

    To be successful in the development of satellite retrieval methodologies for the determination of cirrus cloud properties, fundamental scattering and absorption data on nonspherical ice crystals that are found in cirrus clouds must be available. Recent aircraft observations (Platt et al.) reveal that there is a large amount of small ice particles, on the order of 10 micron, in cirrus clouds. Thus it is important to explore the potential differences in the scattering and absorption properties of ice crystals with respect to their sizes and shapes. In this study the effects of nonspherical small ice crystals on the infrared radiative properties of cirrus clouds are investigated using light scattering properties of spheroidal particles. In Section 2, using the anomalous diffraction theory for spheres and results from the exact spheroid scattering program, efficient parameterization equations are developed for calculations of the scattering and absorption properties for small ice crystals. Parameterization formulas are also developed for large ice crystals using results computed from the geometric ray-tracing technique and the Fraunhofer diffraction theory for spheroids and hexagonal crystals. This is presented in Section 3. Finally, applications to the satellite remote sensing are described in Section 4.

  20. The effect of ice crystal surface roughness on the retrieval of ice cloud microphysical and optical properties 

    E-Print Network [OSTI]

    Xie, Yu

    2007-09-17T23:59:59.000Z

    on the retrieval of ice cloud effective particle size, optical thickness and cloud-top temperature. Three particle surface conditions, smooth, moderately rough and deeply rough, are considered in the visible and near-infrared channels (0.65 and 3.75 Ă...

  1. Ice Heating Up Cold Clouds | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ice Heating Up Cold Clouds Ice Heating Up Cold Clouds Released: October 04, 2011 In a heated battle, ice crystals win the competition for cloud water vapor The mighty cloud ice...

  2. Paper No. ICETECH12-132-RF P. S. Reddy Gudimetla Page number: 1 Strength and Pressure Profiles from Conical Ice Crushing Experiments

    E-Print Network [OSTI]

    Bruneau, Steve

    Paper No. ICETECH12-132-RF P. S. Reddy Gudimetla Page number: 1 Strength and Pressure Profiles from for obtaining the crushing strength and pressure profiles of cone shaped ice samples are presented the response of a full size structural grillage for both quasi-static and dynamic ice loading. To prepare

  3. Pore space percolation in sea ice single crystals D. J. Pringle,1,2

    E-Print Network [OSTI]

    Golden, Kenneth M.

    from 2 to 12% and we found arrays of near-parallel intracrystalline brine layers whose connectivity threshold in the brine microstructure of sea ice. In previous works this critical behavior has been inferred at higher brine volumes by the formation of thin necks between the brine layers. We relate these results

  4. Prediction of Ice Crystal Number in Community Atmospheric Model (CAM3.0)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah ProjectPRE-AWARD ACCOUNTING SYSTEM

  5. Life Cycle of Sea-Ice Frazil, or grease ice

    E-Print Network [OSTI]

    Washington at Seattle, University of

    of Sea Ice away from surface, long crystals as congelation ice (frozen on from below) Brine Channels within the ice (~width of human hair) Brine rejected from ice (4-10psu), but concentrates in brine from AWI #12;Brine Volume and Salinity From Thomas and Dieckmann 2002, Science .... adapted from papers

  6. High-resolution variations in size, number and arrangement of air bubbles in the EPICA DML (Antarctica) ice core

    E-Print Network [OSTI]

    Garbe, Christoph S.

    (Antarctica) ice core Verena BENDEL,1Ă Kai J. UELTZHO¨ FFER,2 Johannes FREITAG,3 Sepp KIPFSTUHL,3 Werner F bubbles in the EPICA Dronning Maud Land (EDML) (Antarctica) ice core, down to the end of the bubble with the palaeo-temperature proxy, dd18 O, and the dust concentration, which means that in Holocene ice

  7. Interstellar Ices

    E-Print Network [OSTI]

    Boogert, A C A

    2003-01-01T23:59:59.000Z

    Currently ~36 different absorption bands have been detected in the infrared spectra of cold, dense interstellar and circumstellar environments. These are attributed to the vibrational transitions of ~17 different molecules frozen on dust grains. We review identification issues and summarize the techniques required to extract information on the physical and chemical evolution of these ices. Both laboratory simulations and line of sight studies are essential. Examples are given for ice bands observed toward high mass protostars, fields stars and recent work on ices in disks surrounding low mass protostars. A number of clear trends have emerged in recent years. One prominent ice component consists of an intimate mixture between H2O, CH3OH and CO2 molecules. Apparently a stable balance exists between low temperature hydrogenation and oxidation reactions on grain surfaces. In contrast, an equally prominent ice component, consisting almost entirely of CO, must have accreted directly from the gas phase. Thermal proc...

  8. Paper No. ICETECH10-XYZ-R0 Hutchings Page number: 1 On the Spatial and Temporal Characterization of Motion Induced Sea Ice Internal Stress

    E-Print Network [OSTI]

    Geiger, Cathleen

    Sea with one aim (among others) of examining the relationship between internal ice stress and ice pack to identify ice motion induced stress from stress measurements recorded at a point in the ice pack, we first induced stress, events impacting any given place in the Arctic ice pack. KEY WORDS: sea ice, Beaufort Sea

  9. MEAT, POULTRY, Still contains ice

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    MEAT, POULTRY, SEAFOOD Still contains ice crystals and feels as cold, and ground meats Refreeze Discard Poultry and ground poultry Refreeze Discard Variety meats may safely re-freeze foods that s:ll contain ice crystals or that have been

  10. Ice sheets

    E-Print Network [OSTI]

    Bentley, Charles G.; Thomas, Robert H.; Velicogna, Isabella

    2007-01-01T23:59:59.000Z

    is eroding West Antarctic Ice Sheet. Geophysical Researchand Yungel, J. (2000). Greenland Ice Sheet: High-Elevation2004). The west Antarctic ice sheet and long term climate

  11. Volume 146,number 1 FEBS LETTERS September 1982 Crystallization of Escherichia coli ribosomes

    E-Print Network [OSTI]

    Yonath, Ada E.

    level in the process of protein bio- synthesis. This information is being obtained by a battery,9]. These have been characterized by three-di- mensional image reconstruction studies [10]. Here we report.4. Characterization of crystallized ribosomes Crystals, together with their growth medium, were placed in 0.7 mm

  12. Method of forming clathrate ice

    DOE Patents [OSTI]

    Hino, Toshiyuki (Tokyo, JP); Gorski, Anthony J. (Lemont, IL)

    1987-01-01T23:59:59.000Z

    A method of forming clathrate ice in a supercooled water-based liquid contained in a vessel is disclosed. Initially, an oscillator device is located in the liquid in the vessel. The oscillator device is then oscillated ultrasonically so that small crystals are formed in the liquid. These small crystals serve as seed crystals for ice formation in the liquid and thereby prevent supercooling of the liquid. Preferably, the oscillating device is controlled by a thermostat which initiates operation of the oscillator device when the temperature of the liquid is lowered to the freezing point. Thereafter, the operation of the oscillator device is terminated when ice is sensed in the liquid by an ice sensor.

  13. Method of forming calthrate ice

    DOE Patents [OSTI]

    Hino, T.; Gorski, A.J.

    1985-09-30T23:59:59.000Z

    A method of forming clathrate ice in a supercooled water-based liquid contained in a vessel is disclosed. Initially, an oscillator device is located in the liquid in the vessel. The oscillator device is then oscillated ultransonically so that small crystals are formed in the liquid. Thes small crystals serve as seed crystals for ice formation in the liquid and thereby prevent supercooling of the liquid. Preferably, the oscillating device is controlled by a thermostat which initiates operation of the oscillator device when the temperature of the liquid is lowered to the freezing point. Thereafter, the operation of the oscillator device is terminated when ice is sensed in the liquid by an ice sensor.

  14. The Development of Measurement Techniques to Identify and Characterize Dusts and Ice Nuclei in the Atmosphere

    E-Print Network [OSTI]

    Glen, Andrew

    2014-01-15T23:59:59.000Z

    Mineral dusts and ice crystals directly influence the Earth's radiative budget through radiative scattering and absorption. The interaction of spherical particles on the radiative budget are well known, however mineral dusts and ice crystals...

  15. Ice nucleation and overseeding of ice in volcanic clouds A. J. Durant,1,2

    E-Print Network [OSTI]

    Rose, William I.

    that such ``overseeded'' volcanic clouds will exhibit enhanced ice crystal concentrations and smaller average ice crystal nucleation in volcanic plumes and clouds affects dynamics [Glaze et al., 1997; Herzog et al., 1998; Mastin- porting water to the stratosphere [Glaze et al., 1997] and these fluxes depend in part on the microphysics

  16. Medical ice slurry production device

    DOE Patents [OSTI]

    Kasza, Kenneth E. (Palos Park, IL); Oras, John (Des Plaines, IL); Son, HyunJin (Naperville, IL)

    2008-06-24T23:59:59.000Z

    The present invention relates to an apparatus for producing sterile ice slurries for medical cooling applications. The apparatus is capable of producing highly loaded slurries suitable for delivery to targeted internal organs of a patient, such as the brain, heart, lungs, stomach, kidneys, pancreas, and others, through medical size diameter tubing. The ice slurry production apparatus includes a slurry production reservoir adapted to contain a volume of a saline solution. A flexible membrane crystallization surface is provided within the slurry production reservoir. The crystallization surface is chilled to a temperature below a freezing point of the saline solution within the reservoir such that ice particles form on the crystallization surface. A deflector in the form of a reciprocating member is provided for periodically distorting the crystallization surface and dislodging the ice particles which form on the crystallization surface. Using reservoir mixing the slurry is conditioned for easy pumping directly out of the production reservoir via medical tubing or delivery through other means such as squeeze bottles, squeeze bags, hypodermic syringes, manual hand delivery, and the like.

  17. Publications by number 1. Synthesis of rhodium (II) pyrazolate complexes. Crystal structure of tetra--3,5-

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    (dimethylphosphino)ethane. X- ray crystal structure of trans-[CrIVCl(NEt)(dmpe)2]CF3SO3, trans- [CrIV(N=CHMe)2(dimpe)2](BPh4

  18. Influence of surface morphology on the immersion mode ice nucleation efficiency of hematite particles

    SciTech Connect (OSTI)

    Hiranuma, Naruki; Hoffmann, Nadine; Kiselev, Alexei; Dreyer, Axel; Zhang, Kai; Kulkarni, Gourihar R.; Koop, Thomas; Mohler, Ottmar

    2014-03-05T23:59:59.000Z

    In this paper, the effect of the morphological modification of aerosol particles with respect to heterogeneous ice nucleation is comprehensively investigated for laboratory-generated hematite particles as a model substrate for atmospheric dust particles. The surface area-scaled ice nucleation efficiencies of monodisperse cubic hematite particles and milled hematite particles were measured with a series of expansion cooling experiments using the Aerosol Interaction and Dynamics in the Atmosphere (AIDA) cloud simulation chamber. Complementary off-line characterization of physico-chemical properties of both hematite subsets were also carried out with scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, dynamic light scattering (DLS), and an electro-kinetical particle charge detector to further constrain droplet-freezing measurements of hematite particles. Additionally, an empirical parameterization derived from our laboratory measurements was implemented in the single-column version of the Community Atmospheric Model version 5 (CAM5) to investigate the model sensitivity in simulated ice crystal number concentration on different ice nucleation efficiencies. From an experimental perspective, our results show that the immersion mode ice nucleation efficiency of milled hematite particles is almost an order of magnitude higher at -35.2 ?C < T < -33.5 ?C than that of the cubic hematite particles, indicating a substantial effect of morphological irregularities on immersion mode freezing. Our modeling results similarly show that the increased droplet-freezing rates of milled hematite particles lead to about one order magnitude higher ice crystal number in the upper troposphere than cubic hematite particles. Overall, our results suggest that the surface irregularities and associated active sites lead to greater ice activation through droplet-freezing.

  19. Archimedean Ice

    E-Print Network [OSTI]

    Kari Eloranta

    2009-09-22T23:59:59.000Z

    The striking boundary dependency (the Arctic Circle phenomenon) exhibited in the ice model on the square lattice extends to other planar set-ups. We present these findings for the triangular and the Kagome lattices. Critical connectivity results guarantee that ice configurations can be generated using the simplest and most efficient local actions. Height functions are utilized throughout the analysis. At the end there is a surprise in store: on the remaining Archimedean lattice for which the ice model can be defined, the 3.4.6.4. lattice, the long range behavior is completely different from the other cases.

  20. Quantum Ice : a quantum Monte Carlo study

    E-Print Network [OSTI]

    Nic Shannon; Olga Sikora; Frank Pollmann; Karlo Penc; Peter Fulde

    2011-12-13T23:59:59.000Z

    Ice states, in which frustrated interactions lead to a macroscopic ground-state degeneracy, occur in water ice, in problems of frustrated charge order on the pyrochlore lattice, and in the family of rare-earth magnets collectively known as spin ice. Of particular interest at the moment are "quantum spin ice" materials, where large quantum fluctuations may permit tunnelling between a macroscopic number of different classical ground states. Here we use zero-temperature quantum Monte Carlo simulations to show how such tunnelling can lift the degeneracy of a spin or charge ice, stabilising a unique "quantum ice" ground state --- a quantum liquid with excitations described by the Maxwell action of 3+1-dimensional quantum electrodynamics. We further identify a competing ordered "squiggle" state, and show how both squiggle and quantum ice states might be distinguished in neutron scattering experiments on a spin ice material.

  1. Aerosol Effects on Cirrus through Ice Nucleation in the Community Atmosphere Model CAM5 with a Statistical Cirrus Scheme

    SciTech Connect (OSTI)

    Wang, Minghuai; Liu, Xiaohong; Zhang, Kai; Comstock, Jennifer M.

    2014-09-01T23:59:59.000Z

    A statistical cirrus cloud scheme that tracks ice saturation ratio in the clear-sky and cloudy portion of a grid box separately has been implemented into NCAR CAM5 to provide a consistent treatment of ice nucleation and cloud formation. Simulated ice supersaturation and ice crystal number concentrations strongly depend on the number concentrations of heterogeneous ice nuclei (IN), subgrid temperature formulas and the number concentration of sulfate particles participating in homogeneous freezing, while simulated ice water content is insensitive to these perturbations. 1% to 10% dust particles serving as heterogeneous IN is 20 found to produce ice supersaturaiton in better agreement with observations. Introducing a subgrid temperature perturbation based on long-term aircraft observations of meso-scale motion produces a better hemispheric contrast in ice supersaturation compared to observations. Heterogeneous IN from dust particles significantly alter the net radiative fluxes at the top of atmosphere (TOA) (-0.24 to -1.59 W m-2) with a significant clear-sky longwave component (0.01 to -0.55 W m-2). Different cirrus treatments significantly perturb the net TOA anthropogenic aerosol forcing from -1.21 W m-2 to -1.54 W m-2, with a standard deviation of 0.10 W m-2. Aerosol effects on cirrus clouds exert an even larger impact on the atmospheric component of the radiative fluxes (two or three times the changes in the TOA radiative fluxes) and therefore on the hydrology cycle through the fast atmosphere response. This points to the urgent need to quantify aerosol effects on cirrus clouds through ice nucleation and how these further affect the hydrological cycle.

  2. How Physical and Chemical Properties Change Ice Nucleation Efficiency of Soot and Polyaromatic Hydrocarbon Particles

    E-Print Network [OSTI]

    Suter, Katie Ann

    2012-10-19T23:59:59.000Z

    Heterogeneous freezing processes in which atmospheric aerosols act as ice nuclei (IN) cause nucleation of ice crystals in the atmosphere. Heterogeneous nucleation can occur through several freezing mechanisms, including contact and immersion...

  3. Iced Coffee Iced Yerba Mate "Tea"

    E-Print Network [OSTI]

    Iced Coffee Iced Yerba Mate "Tea" Iced Yerba Mate Latte Iced Chai Tea Latte Original, Green Tea Canned Soda Xing Tea Bottled Water Arizona Teas Energy Drinks Red Bull, SF Red Bull & Bing Jones Sodas $0 Cafe au Lait Hot Tea Yerba Mate "Tea" Yerba Mate Latte Chai Tea Latte - Original, Green Tea, or Sugar

  4. Parameterizing Size Distribution in Ice Clouds

    SciTech Connect (OSTI)

    DeSlover, Daniel; Mitchell, David L.

    2009-09-25T23:59:59.000Z

    PARAMETERIZING SIZE DISTRIBUTIONS IN ICE CLOUDS David L. Mitchell and Daniel H. DeSlover ABSTRACT An outstanding problem that contributes considerable uncertainty to Global Climate Model (GCM) predictions of future climate is the characterization of ice particle sizes in cirrus clouds. Recent parameterizations of ice cloud effective diameter differ by a factor of three, which, for overcast conditions, often translate to changes in outgoing longwave radiation (OLR) of 55 W m-2 or more. Much of this uncertainty in cirrus particle sizes is related to the problem of ice particle shattering during in situ sampling of the ice particle size distribution (PSD). Ice particles often shatter into many smaller ice fragments upon collision with the rim of the probe inlet tube. These small ice artifacts are counted as real ice crystals, resulting in anomalously high concentrations of small ice crystals (D < 100 µm) and underestimates of the mean and effective size of the PSD. Half of the cirrus cloud optical depth calculated from these in situ measurements can be due to this shattering phenomenon. Another challenge is the determination of ice and liquid water amounts in mixed phase clouds. Mixed phase clouds in the Arctic contain mostly liquid water, and the presence of ice is important for determining their lifecycle. Colder high clouds between -20 and -36 oC may also be mixed phase but in this case their condensate is mostly ice with low levels of liquid water. Rather than affecting their lifecycle, the presence of liquid dramatically affects the cloud optical properties, which affects cloud-climate feedback processes in GCMs. This project has made advancements in solving both of these problems. Regarding the first problem, PSD in ice clouds are uncertain due to the inability to reliably measure the concentrations of the smallest crystals (D < 100 µm), known as the “small mode”. Rather than using in situ probe measurements aboard aircraft, we employed a treatment of ice cloud optical properties formulated in terms of PSD parameters in combination with remote measurements of thermal radiances to characterize the small mode. This is possible since the absorption efficiency (Qabs) of small mode crystals is larger at 12 µm wavelength relative to 11 µm wavelength due to the process of wave resonance or photon tunneling more active at 12 µm. This makes the 12/11 µm absorption optical depth ratio (or equivalently the 12/11 µm Qabs ratio) a means for detecting the relative concentration of small ice particles in cirrus. Using this principle, this project tested and developed PSD schemes that can help characterize cirrus clouds at each of the three ARM sites: SGP, NSA and TWP. This was the main effort of this project. These PSD schemes and ice sedimentation velocities predicted from them have been used to test the new cirrus microphysics parameterization in the GCM known as the Community Climate Systems Model (CCSM) as part of an ongoing collaboration with NCAR. Regarding the second problem, we developed and did preliminary testing on a passive thermal method for retrieving the total water path (TWP) of Arctic mixed phase clouds where TWPs are often in the range of 20 to 130 g m-2 (difficult for microwave radiometers to accurately measure). We also developed a new radar method for retrieving the cloud ice water content (IWC), which can be vertically integrated to yield the ice water path (IWP). These techniques were combined to determine the IWP and liquid water path (LWP) in Arctic clouds, and hence the fraction of ice and liquid water. We have tested this approach using a case study from the ARM field campaign called M-PACE (Mixed-Phase Arctic Cloud Experiment). This research led to a new satellite remote sensing method that appears promising for detecting low levels of liquid water in high clouds typically between -20 and -36 oC. We hope to develop this method in future research.

  5. Tellus (1989), 41A, 132-147 The effect of parameterized ice microphysics on the

    E-Print Network [OSTI]

    Zhang, Da-Lin

    Tellus (1989), 41A, 132-147 The effect of parameterized ice microphysics on the simulation and associated stratiform rainfall. In this paper, parameterized cloud ice and snow crystals are incorporated on a grid resolution of 25 km. With the inclusion of ice microphysics parameterization. the resolvable

  6. Department of Computer Science University of North Carolina at Chapel Hill March 2005 The visual complexity of ice is familiar to anyone who has

    E-Print Network [OSTI]

    Whitton, Mary C.

    The visual complexity of ice is familiar to anyone who has ever studied a snowflake or seen the crystal snowflake-like patterns. The Challenge The visual appeal of patterns in ice has not been lost on the visual of knowledge in both the crystal growth and computational physics communities that Pattern Formation in Ice

  7. CMU-ITC-83-029 WHITE PAPER: The ICE Execution Environment

    E-Print Network [OSTI]

    CMU-ITC-83-029 WHITE PAPER: The ICE Execution Environment Document Number 003-001/002.01 DRAFT-Mellon University Schenley Park Pittsburgh, PA 15213 #12;The ICE Execution Environment DRAFT 003- 001/002.01 U ncla ssified ( 2 The ICE Execution Environment #12;The ICE Execution Environment DRAFT 003

  8. First Data from DM-Ice17

    E-Print Network [OSTI]

    :,; Grant, D; Halzen, F; Heeger, K M; Hsu, L; Hubbard, A J F; Karle, A; Kauer, M; Kudryavtsev, V A; Maruyama, R H; MacDonald, C; Paling, S; Pettus, W C; Pierpoint, Z P; Reilly, B N; Robinson, M; Sandstrom, P; Spooner, N J C; Telfer, S; Yang, L

    2014-01-01T23:59:59.000Z

    We report the first analysis of background data from DM-Ice17 a direct-detection dark matter experiment consisting of 17 kg of NaI(Tl) target material. It was successfully deployed 2457 m deep in South Pole glacial ice at the bottom of two IceCube strings in December 2010 and is the first such detector to be operating in the Southern Hemisphere. Data from the first two years of operation after commissioning, July 2011 - June 2013, are presented here. The background rate in the 6.5 - 8.0 kevee region is measured to be 7.9 +/- 0.4 counts/day/keV/kg. This is in agreement with the expected background from the crystal assemblies and is consistent with simulation. Background contributions from the surrounding ice were demonstrated to be negligible. The successful deployment and operation of DM-Ice17 establishes the South Pole ice as a location for future underground, low-background experiments in the Southern Hemisphere. The detector assembly, deployment, and analysis of the DM-Ice17 backgrounds are described.

  9. How atmospheric ice forms | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    atmospheric ice forms How atmospheric ice forms Released: September 08, 2014 New insights into atmospheric ice formation could improve climate models This study advances our...

  10. Arctic ice islands

    SciTech Connect (OSTI)

    Sackinger, W.M.; Jeffries, M.O.; Lu, M.C.; Li, F.C.

    1988-01-01T23:59:59.000Z

    The development of offshore oil and gas resources in the Arctic waters of Alaska requires offshore structures which successfully resist the lateral forces due to moving, drifting ice. Ice islands are floating, a tabular icebergs, up to 60 meters thick, of solid ice throughout their thickness. The ice islands are thus regarded as the strongest ice features in the Arctic; fixed offshore structures which can directly withstand the impact of ice islands are possible but in some locations may be so expensive as to make oilfield development uneconomic. The resolution of the ice island problem requires two research steps: (1) calculation of the probability of interaction between an ice island and an offshore structure in a given region; and (2) if the probability if sufficiently large, then the study of possible interactions between ice island and structure, to discover mitigative measures to deal with the moving ice island. The ice island research conducted during the 1983-1988 interval, which is summarized in this report, was concerned with the first step. Monte Carlo simulations of ice island generation and movement suggest that ice island lifetimes range from 0 to 70 years, and that 85% of the lifetimes are less then 35 years. The simulation shows a mean value of 18 ice islands present at any time in the Arctic Ocean, with a 90% probability of less than 30 ice islands. At this time, approximately 34 ice islands are known, from observations, to exist in the Arctic Ocean, not including the 10-meter thick class of ice islands. Return interval plots from the simulation show that coastal zones of the Beaufort and Chukchi Seas, already leased for oil development, have ice island recurrences of 10 to 100 years. This implies that the ice island hazard must be considered thoroughly, and appropriate safety measures adopted, when offshore oil production plans are formulated for the Alaskan Arctic offshore. 132 refs., 161 figs., 17 tabs.

  11. Creep and plasticity of glacier ice: a material science perspective Paul DUVAL, Maurine MONTAGNAT, Fanny GRENNERAT, Jerome WEISS,

    E-Print Network [OSTI]

    Weiss, Jérôme

    Creep and plasticity of glacier ice: a material science perspective Paul DUVAL, Maurine MONTAGNAT the plasticity of ice have been made during the past 60 years with the development of studies of the flow experimental investigations clearly show that the plastic deformation of the ice single crystal and polycrystal

  12. Ice electrode electrolytic cell

    DOE Patents [OSTI]

    Glenn, David F. (Idaho Falls, ID); Suciu, Dan F. (Idaho Falls, ID); Harris, Taryl L. (Idaho Falls, ID); Ingram, Jani C. (Idaho Falls, ID)

    1993-01-01T23:59:59.000Z

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  13. Ice electrode electrolytic cell

    DOE Patents [OSTI]

    Glenn, D.F.; Suciu, D.F.; Harris, T.L.; Ingram, J.C.

    1993-04-06T23:59:59.000Z

    This invention relates to a method and apparatus for removing heavy metals from waste water, soils, or process streams by electrolytic cell means. The method includes cooling a cell cathode to form an ice layer over the cathode and then applying an electric current to deposit a layer of the heavy metal over the ice. The metal is then easily removed after melting the ice. In a second embodiment, the same ice-covered electrode can be employed to form powdered metals.

  14. Using ice cores from the East Antarctic Ice Sheet, scientists have been able to study

    E-Print Network [OSTI]

    Using ice cores from the East Antarctic Ice Sheet, scientists have been able to study ice's ice sheets. Ice sheets are huge areas of permanent ice. There are only three ice sheets on Earth: the Greenland Ice Sheet, the West Antarctic Ice Sheet, and the East Antarctic Ice Sheet. The Greenland Ice Sheet

  15. Premelting, fluctuations, and coarse-graining of water-ice interfaces

    SciTech Connect (OSTI)

    Limmer, David T., E-mail: dlimmer@princeton.edu [Princeton Center for Theoretical Science, Princeton University, Princeton, New Jersey 08540 (United States); Chandler, David [Department of Chemistry, University of California, Berkeley, California 94609 (United States)

    2014-11-14T23:59:59.000Z

    Using statistical field theory supplemented with molecular dynamics simulations, we consider premelting on the surface of ice as a generic consequence of broken hydrogen bonds at the boundary between the condensed and gaseous phases. A procedure for coarse-graining molecular configurations onto a continuous scalar order parameter field is discussed, which provides a convenient representation of the interface between locally crystal-like and locally liquid-like regions. A number of interfacial properties are straightforwardly evaluated using this procedure such as the average premelting thickness and surface tension. The temperature and system size dependence of the premelting layer thickness calculated in this way confirms the characteristic logarithmic growth expected for the scalar field theory that the system is mapped onto through coarse-graining, though remains finite due to long-ranged interactions. Finally, from explicit simulations the existence of a premelting layer is shown to be insensitive to bulk lattice geometry, exposed crystal face, and curvature.

  16. Field demonstration of the ICE 250{trademark} Cleaning System

    SciTech Connect (OSTI)

    Johnston, J.L.; Jackson, L.M.

    1999-10-05T23:59:59.000Z

    The ICE 250{trademark} Cleaning System was engineered to convert water into small ice particles for use in cleaning and decontamination applications. Ice crystals are produced in a special icemaker and pressured through a hose-nozzle onto the surface to be cleaned. The Rocky Mountain Oilfield Testing Center and Ice Cleaning Systems, Inc., conducted a test of this system at Naval Petroleum Reserve No. 3 to evaluate the system's cleaning capabilities in an oil field environment. Equipment cleaned included an oil storage tank, a rod pumping unit, a road grader, and a wellhead. Contaminants were unrefined sour crude oil, hydraulic fluid, paraffin, and dirt, occurring separately and as mixtures. In all four demonstration cleaning tasks, the ICE 250 System effectively removed surface contaminant mixtures in a timely manner and left no oily residue. A minimal amount of waste moisture was generated, thereby reducing cleanup and disposal costs.

  17. Field demonstration of the ICE 250[trademark] Cleaning System

    SciTech Connect (OSTI)

    Johnston, J.L.; Jackson, L.M.

    1999-10-05T23:59:59.000Z

    The ICE 250[trademark] Cleaning System was engineered to convert water into small ice particles for use in cleaning and decontamination applications. Ice crystals are produced in a special icemaker and pressured through a hose-nozzle onto the surface to be cleaned. The Rocky Mountain Oilfield Testing Center and Ice Cleaning Systems, Inc., conducted a test of this system at Naval Petroleum Reserve No. 3 to evaluate the system's cleaning capabilities in an oil field environment. Equipment cleaned included an oil storage tank, a rod pumping unit, a road grader, and a wellhead. Contaminants were unrefined sour crude oil, hydraulic fluid, paraffin, and dirt, occurring separately and as mixtures. In all four demonstration cleaning tasks, the ICE 250 System effectively removed surface contaminant mixtures in a timely manner and left no oily residue. A minimal amount of waste moistur2048s generated, thereby reducing cleanup and disposal costs.

  18. Enhanced residual entropy in high-density nanoconfined bilayer ice

    E-Print Network [OSTI]

    Fabiano Corsetti; Jon Zubeltzu; Emilio Artacho

    2015-06-15T23:59:59.000Z

    A novel kind of crystal order in high-density nanoconfined bilayer ice is proposed from molecular dynamics and density-functional theory simulations. A first-order transition is observed between a low-temperature proton-ordered solid and a high-temperature proton-disordered solid. The latter is shown to possess crystalline order for the oxygen positions, arranged on a close-packed triangular lattice with AA stacking. Uniquely amongst the ice phases, the triangular bilayer is characterized by two levels of disorder (for the bonding network and for the protons) which results in a residual entropy twice that of bulk ice.

  19. Study of Ice Cloud Properties from Synergetic Use of Satellite Observations and Modeling Capabilities

    E-Print Network [OSTI]

    Xie, Yu

    2011-02-22T23:59:59.000Z

    The dissertation first investigates the single-scattering properties of inhomogeneous ice crystals containing air bubbles. Specifically, a combination of the ray-tracing technique and the Monte Carlo method is used to simulate the scattering...

  20. Transporting Dry Ice

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Requirements for Shipping Dry Ice IATA PI 904 Source: Reg of the Day from ERCweb 2006 Environmental Resource Center | 919-469-1585 | webmaster@ercweb.com http:...

  1. Ice Drilling Gallonmilkjugs

    E-Print Network [OSTI]

    Saffman, Mark

    Ice Drilling Materials · Gallonmilkjugs · Syringes,largeand small · Pitchers · Spraybottles · 13x9? ·Isitbettertosquirtthewaterslowlyorasquicklyaspossible? ·Doestherateatwhichyousquirtthewaterchangethediameteroftheholes? ·Doesthetypeof`drill

  2. Sandia National Laboratories: ICED

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Paper Presented at American Society of Mechanical Engineers' (ASME) 2012 Internal Combustion Engine Division (ICED) Conference On August 28, 2013, in CRF, Energy, Energy...

  3. Mobile Ice Nucleus Spectrometer

    SciTech Connect (OSTI)

    Kulkarni, Gourihar R.; Kok, G. L.

    2012-05-07T23:59:59.000Z

    This first year report presents results from a computational fluid dynamics (CFD) study to assess the flow and temperature profiles within the mobile ice nucleus spectrometer.

  4. Proton ordering in tetragonal and monoclinic H2O ice

    E-Print Network [OSTI]

    Yen, Fei; Berlie, Adam; Liu, Xiaodi; Goncharov, Alexander F

    2015-01-01T23:59:59.000Z

    H2O ice remains one of the most enigmatic materials as its phase diagram reveals up to sixteen solid phases. While the crystal structure of these phases has been determined, the phase boundaries and mechanisms of formation of the proton-ordered phases remain unclear. From high precision measurements of the complex dielectric constant, we probe directly the degree of ordering of the protons in H2O tetragonal ice III and monoclinic ice V down to 80 K. A broadened first-order phase transition is found to occur near 202 K we attribute to a quenched disorder of the protons which causes a continuous disordering of the protons during cooling and metastable behavior. At 126 K the protons in ice III become fully ordered, and for the case of ice V becoming fully ordered at 113 K forming ice XIII. Two triple points are proposed to exist: one at 0.35 GPa and 126 K where ices III, IX and V coexist; and another at 0.35 GPa and 113 K where ices V, IX and XIII coexist. Our findings unravel the underlying mechanism driving th...

  5. INVESTIGATION OF SEASONAL SEA-ICE THICKNESS VARIABILITY IN THE ROSS SEA Beth A. Schellenberg

    E-Print Network [OSTI]

    Geiger, Cathleen

    archive consists of over 20,000 records over the Antarc- tic pack ice between 1980 and the presentINVESTIGATION OF SEASONAL SEA-ICE THICKNESS VARIABILITY IN THE ROSS SEA Beth A. Schellenberg P1.23 1. INTRODUCTION A number of studies suggest a connections between sea-ice variability

  6. Ice chemistry in starless molecular cores

    E-Print Network [OSTI]

    Kalvans, Juris

    2015-01-01T23:59:59.000Z

    Starless molecular cores are natural laboratories for interstellar molecular chemistry research. The chemistry of ices in such objects was investigated with a three-phase (gas, surface, and mantle) model. We considered the center part of five starless cores, with their physical conditions derived from observations. The ice chemistry of oxygen, nitrogen, sulfur, and complex organic molecules (COMs) was analyzed. We found that an ice-depth dimension, measured, e.g., in monolayers, is essential for modeling of chemistry in interstellar ices. Particularly, the H2O:CO:CO2:N2:NH3 ice abundance ratio regulates the production and destruction of minor species. It is suggested that photodesorption during core collapse period is responsible for high abundance of interstellar H2O2 and O2H, and other species synthesized on the surface. The calculated abundances of COMs in ice were compared to observed gas-phase values. Smaller activation barriers for CO and H2CO hydrogenation may help explain the production of a number of...

  7. Ice particle size matters | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ice particle size matters Ice particle size matters Released: May 04, 2014 Fine-tuning cloud models for improved climate predictions The Science Arctic clouds are widespread and...

  8. Final Technical Report for "Ice nuclei relation to aerosol properties: Data analysis and model parameterization for IN in mixed-phase clouds"Ă?Âť (DOE/SC00002354)

    SciTech Connect (OSTI)

    Paul J. DeMott, Anthony J. Prenni; Sonia M. Kreidenweis

    2012-09-28T23:59:59.000Z

    Clouds play an important role in weather and climate. In addition to their key role in the hydrologic cycle, clouds scatter incoming solar radiation and trap infrared radiation from the surface and lower atmosphere. Despite their importance, feedbacks involving clouds remain as one of the largest sources of uncertainty in climate models. To better simulate cloud processes requires better characterization of cloud microphysical processes, which can affect the spatial extent, optical depth and lifetime of clouds. To this end, we developed a new parameterization to be used in numerical models that describes the variation of ice nuclei (IN) number concentrations active to form ice crystals in mixed-phase (water droplets and ice crystals co-existing) cloud conditions as these depend on existing aerosol properties and temperature. The parameterization is based on data collected using the Colorado State University continuous flow diffusion chamber in aircraft and ground-based campaigns over a 14-year period, including data from the DOE-supported Mixed-Phase Arctic Cloud Experiment. The resulting relationship is shown to more accurately represent the variability of ice nuclei distributions in the atmosphere compared to currently used parameterizations based on temperature alone. When implemented in one global climate model, the new parameterization predicted more realistic annually averaged cloud water and ice distributions, and cloud radiative properties, especially for sensitive higher latitude mixed-phase cloud regions. As a test of the new global IN scheme, it was compared to independent data collected during the 2008 DOE-sponsored Indirect and Semi-Direct Aerosol Campaign (ISDAC). Good agreement with this new data set suggests the broad applicability of the new scheme for describing general (non-chemically specific) aerosol influences on IN number concentrations feeding mixed-phase Arctic stratus clouds. Finally, the parameterization was implemented into a regional cloud-resolving model to compare predictions of ice crystal concentrations and other cloud properties to those observed in two intensive case studies of Arctic stratus during ISDAC. Our implementation included development of a prognostic scheme of ice activation using the IN parameterization so that the most realistic treatment of ice nuclei, including their budget (gains and losses), was achieved. Many cloud microphysical properties and cloud persistence were faithfully reproduced, despite a tendency to under-predict (by a few to several times) ice crystal number concentrations and cloud ice mass, in agreement with some other studies. This work serves generally as the basis for improving predictive schemes for cloud ice crystal activation in cloud and climate models, and more specifically as the basis for such a scheme to be used in a Multi-scale Modeling Format (MMF) that utilizes a connected system of cloud-resolving models on a global grid in an effort to better resolve cloud processes and their influence on climate.

  9. Reionization on ice

    E-Print Network [OSTI]

    C. C. Dudley; M. Imanishi; P. R. Maloney

    2006-02-15T23:59:59.000Z

    The case for substantial far infrared ice emission in local ultraluminous infrared galaxies, expected based on the presence of mid-infrared ice absorption in their spectra and the known far infrared optical properties of ice, is still largely unsupported by direct observation owing to insufficient far infrared spectral coverage. Some marginal supportive evidence is presented here. A clear consequence of far infrared ice emission is the need to extend the range of redshifts considered for submillimeter sources. This is demonstrated via the example of HDF 850.1. The solid phase of the ISM during reionization may be dominated by ice, and this could lead to the presence of reionization sources in submillimeter source catalogs. Submillimeter sources not detected at 24 micron in the GOODS-N field are examined. Two candidate reionization sources are identified at 3.6 micron through possible Gunn-Peterson saturation in the Z band.

  10. Very ice rich permafrost Moderately ice rich permafrost

    E-Print Network [OSTI]

    Ruess, Roger W.

    TK lake Very ice rich permafrost Permafrost forest Moderately ice rich permafrost Open Bog Open Fen characteristics (mainly ice content) and burn severity determine trajectories of ecosystem succession post in the presence of moderately ice rich permafrost but have high resilience only under low burn severity in very

  11. Ice Cream with a Heart Create a new Clemson Ice

    E-Print Network [OSTI]

    Duchowski, Andrew T.

    Ice Cream with a Heart Contest! Create a new Clemson Ice Cream flavor! Raise money for your favorite charity! Win a free Clemson Ice Cream party for your organization! Enter at www organizations. The contest is called Ice Cream with a Heart and its purpose is to help student organizations

  12. Thermal desorption of CH4 retained in CO2 ice

    E-Print Network [OSTI]

    R. Luna; C. Millan; M. Domingo; M. A. Satorre

    2008-01-21T23:59:59.000Z

    CO2 ices are known to exist in different astrophysical environments. In spite of this, its physical properties (structure, density, refractive index) have not been as widely studied as those of water ice. It would be of great value to study the adsorption properties of this ice in conditions related to astrophysical environments. In this paper, we explore the possibility that CO2 traps relevant molecules in astrophysical environments at temperatures higher than expected from their characteristic sublimation point. To fulfil this aim we have carried out desorption experiments under High Vacuum conditions based on a Quartz Crystal Microbalance and additionally monitored with a Quadrupole Mass Spectrometer. From our results, the presence of CH4 in the solid phase above the sublimation temperature in some astrophysical scenarios could be explained by the presence of several retaining mechanisms related to the structure of CO2 ice.

  13. Thermal desorption of CH4 retained in CO2 ice

    E-Print Network [OSTI]

    Luna, R; Domingo, M; Satorre, M A

    2008-01-01T23:59:59.000Z

    CO2 ices are known to exist in different astrophysical environments. In spite of this, its physical properties (structure, density, refractive index) have not been as widely studied as those of water ice. It would be of great value to study the adsorption properties of this ice in conditions related to astrophysical environments. In this paper, we explore the possibility that CO2 traps relevant molecules in astrophysical environments at temperatures higher than expected from their characteristic sublimation point. To fulfil this aim we have carried out desorption experiments under High Vacuum conditions based on a Quartz Crystal Microbalance and additionally monitored with a Quadrupole Mass Spectrometer. From our results, the presence of CH4 in the solid phase above the sublimation temperature in some astrophysical scenarios could be explained by the presence of several retaining mechanisms related to the structure of CO2 ice.

  14. An ice shelf breakup

    SciTech Connect (OSTI)

    Fahnestock, M. [Univ. of Maryland, College Park, MD (United States)

    1996-02-09T23:59:59.000Z

    Glaciers and ice sheets are controlled by the climate and must change if the conditions that led to their current configurations are changing. These ice masses exist at the interface between the atmosphere, which provides sustaining snowfall and thermal regulation, and the land, which provides a stable base and in many cases the elevation required to reach suitably cold conditions. Ice sheets and glaciers are distributed around the globe and can serve as potential indicators of past climate variability and current climatic trends. 9 refs.

  15. Designing for effective stationkeeping in ice

    E-Print Network [OSTI]

    Nřrvĺg, Kjetil

    Designing for effective stationkeeping in ice CeSOS Highlights and AMOS Visions Conference DP Ice loads Ice #12;Effective stationkeeping in ice 1. Effective ship design. 2. An effective Ice Management system. 3. Effective strategies for the DP control system to compensate ice forces. #12;Ice

  16. Global ice sheet modeling

    SciTech Connect (OSTI)

    Hughes, T.J.; Fastook, J.L. [Univ. of Maine, Orono, ME (United States). Institute for Quaternary Studies

    1994-05-01T23:59:59.000Z

    The University of Maine conducted this study for Pacific Northwest Laboratory (PNL) as part of a global climate modeling task for site characterization of the potential nuclear waste respository site at Yucca Mountain, NV. The purpose of the study was to develop a global ice sheet dynamics model that will forecast the three-dimensional configuration of global ice sheets for specific climate change scenarios. The objective of the third (final) year of the work was to produce ice sheet data for glaciation scenarios covering the next 100,000 years. This was accomplished using both the map-plane and flowband solutions of our time-dependent, finite-element gridpoint model. The theory and equations used to develop the ice sheet models are presented. Three future scenarios were simulated by the model and results are discussed.

  17. Ice Formation in Gas-Diffusion Layers

    E-Print Network [OSTI]

    Dursch, Thomas

    2013-01-01T23:59:59.000Z

    the University of California. Ice Formation in Gas-Diffusionsub-freezing conditions, ice forms in the gas-diffusionstrategies exist to prevent ice formation, there is little

  18. WATER ICE IN THE KUIPER BELT

    SciTech Connect (OSTI)

    Brown, M. E.; Fraser, W. C. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Schaller, E. L., E-mail: mbrown@caltech.edu [NASA Dryden Aircraft Operations Facility, Palmdale, CA 93550 (United States)

    2012-06-15T23:59:59.000Z

    We examine a large collection of low-resolution near-infrared spectra of Kuiper Belt objects (KBOs) and centaurs in an attempt to understand the presence of water ice in the Kuiper Belt. We find that water ice on the surface of these objects occurs in three separate manners: (1) Haumea family members uniquely show surfaces of nearly pure water ice, presumably a consequence of the fragmentation of the icy mantle of a larger differentiated proto-Haumea; (2) large objects with absolute magnitudes of H < 3 (and a limited number to H = 4.5) have surface coverings of water ice-perhaps mixed with ammonia-that appears to be related to possibly ancient cryovolcanism on these large objects; and (3) smaller KBOs and centaurs which are neither Haumea family members nor cold-classical KBOs appear to divide into two families (which we refer to as 'neutral' and 'red'), each of which is a mixture of a common nearly neutral component and either a slightly red or very red component that also includes water ice. A model suggesting that the difference between neutral and red objects due to formation in an early compact solar system either inside or outside, respectively, of the {approx}20 AU methanol evaporation line is supported by the observation that methanol is only detected on the reddest objects, which are those which would be expected to have the most of the methanol containing mixture.

  19. Commercial Application of Freeze Crystallization

    E-Print Network [OSTI]

    Gorgol, R. G.

    COMMERCIAL APPLICATION OF FREEZE CRYSTALLIZATION ROBERT G. GORGOL, MARKETING MANAGER, HPD INCORPORATED, NAPERVILLE, ILLINOIS ABSTRACT Industrial usc of frcezing for componcnt purification and separation is well understood, but commercial... of purification, but they did understand the water they obtained from ice was potable. RECENT APPLICATIONS Scientists have understood the basic mechanism of the freezing phase change for many years. ID an effort to harness the power of this phenomena...

  20. The different facets of ice have different hydrophilicities: Friction at water / ice-I$_\\mathrm{h}$ interfaces

    E-Print Network [OSTI]

    Louden, Patrick B

    2015-01-01T23:59:59.000Z

    We present evidence that the prismatic and secondary prism facets of ice-I$_\\mathrm{h}$ crystals possess structural features that can reduce the effective hydrophilicity of the ice/water interface. The spreading dynamics of liquid water droplets on ice facets exhibits long-time behavior that differs for the prismatic $\\{10\\bar{1}0\\}$ and secondary prism $\\{11\\bar{2}0\\}$ facets when compared with the basal $\\{0001\\}$ and pyramidal $\\{20\\bar{2}1\\}$ facets. We also present the results of simulations of solid-liquid friction of the same four crystal facets being drawn through liquid water, and find that the two prismatic facets exhibit roughly half the solid-liquid friction of the basal and pyramidal facets. These simulations provide evidence that the two prismatic faces have a significantly smaller effective surface area in contact with the liquid water. The ice / water interfacial widths for all four crystal facets are similar (using both structural and dynamic measures), and were found to be independent of the...

  1. Coherent radar ice thickness measurements over the Greenland ice sheet

    E-Print Network [OSTI]

    Gogineni, S. Prasad; Tammana, Dilip; Braaten, David A.; Leuschen, C.; Legarsky, J.; Kanagaratnam, P.; Stiles, J.; Allen, C.; Jezek, K.; Akins, T.

    2001-12-27T23:59:59.000Z

    We developed two 150-MHz coherent radar depth sounders for ice thickness measurements over the Greenland ice sheet. We developed one of these using connectorized components and the other using radio frequency integrated circuits (RFICs). Both...

  2. Hail ice impact on composite structures at glancing angles

    E-Print Network [OSTI]

    Funai, Sho

    2012-01-01T23:59:59.000Z

    investigation of high velocity ice impacts on woven carbon/and ice sphere. .by trailing ice fragments. ..

  3. Image Content Engine (ICE)

    SciTech Connect (OSTI)

    Brase, J M

    2007-03-26T23:59:59.000Z

    The Image Content Engine (ICE) is being developed to provide cueing assistance to human image analysts faced with increasingly large and intractable amounts of image data. The ICE architecture includes user configurable feature extraction pipelines which produce intermediate feature vector and match surface files which can then be accessed by interactive relational queries. Application of the feature extraction algorithms to large collections of images may be extremely time consuming and is launched as a batch job on a Linux cluster. The query interface accesses only the intermediate files and returns candidate hits nearly instantaneously. Queries may be posed for individual objects or collections. The query interface prompts the user for feedback, and applies relevance feedback algorithms to revise the feature vector weighting and focus on relevant search results. Examples of feature extraction and both model-based and search-by-example queries are presented.

  4. Ice Cover on the Great Lakes NATIONALOCEANIC

    E-Print Network [OSTI]

    Ice Cover on the Great Lakes NATIONALOCEANIC AND ATMOSPHERIC ADMINISTRATION U.S. D EPARTMENT OF COMM ER CE Great Lakes Ice Cover facts since 1973 - 94.7% ice coverage in 1979 is the maximum on record - 9.5% ice coverage in 2002 is the lowest on record - 11.5% ice coverage in 1998, a strong El Nino

  5. Engineering Notes Ice Shape Characterization Using

    E-Print Network [OSTI]

    Tino, Peter

    Engineering Notes Ice Shape Characterization Using Self-Organizing Maps Stephen T. McClain Baylor. Introduction DURING the validation and verification of ice accretion codes, predicted ice shapes must be compared with experimental measurements of wind-tunnel or atmospheric ice shapes. Current methods for ice

  6. Hidden force floating ice

    E-Print Network [OSTI]

    Chang Q. Sun

    2015-01-17T23:59:59.000Z

    Because of the segmental specific-heat disparity of the hydrogen bond (O:H-O) and the Coulomb repulsion between oxygen ions, cooling elongates the O:H-O bond at freezing by stretching its containing angle and shortening the H-O bond with an association of larger O:H elongation, which makes ice less dense than water, allowing it to float.

  7. Ice Storm Supercomputer

    ScienceCinema (OSTI)

    None

    2013-05-28T23:59:59.000Z

    "A new Idaho National Laboratory supercomputer is helping scientists create more realistic simulations of nuclear fuel. Dubbed 'Ice Storm,' this 2048-processor machine allows researchers to model and predict the complex physics behind nuclear reactor behavior. And with a new visualization lab, the team can see the results of its simulations on the big screen." For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

  8. Greenland Ice Sheet Retreat Since the Little Ice Age

    E-Print Network [OSTI]

    Beitch, Marci Jillian

    2014-01-01T23:59:59.000Z

    and I. Willis (2012), Greenland's shrinking ice cover: "fastfluctuations in southeast Greenland, Nat. Geosci. , 5(6),T. Decker (2011), Analysis of Greenland marine- terminating

  9. Ice Mass Balance Buoy: An Instrument to Measure and Attribute Changes in Ice Thickness

    E-Print Network [OSTI]

    Geiger, Cathleen

    Ice Mass Balance Buoy: An Instrument to Measure and Attribute Changes in Ice Thickness Jacqueline A the Ice Mass Balance buoy (IMB) in response to the need for monitoring changes in the thickness of the Arctic sea ice cover. The IMB is an autonomous, ice-based system. IMB buoys provide a time series of ice

  10. NOTES AND CORRESPONDENCE Surface Melting over Ice Shelves and Ice Sheets as Assessed from Modeled

    E-Print Network [OSTI]

    Meissner, Katrin Juliane

    NOTES AND CORRESPONDENCE Surface Melting over Ice Shelves and Ice Sheets as Assessed from Modeled of ice shelves and their progenitor ice sheets. To explore the magnitude of surface melt occurring over modern ice shelves and ice sheets in a climate scenario forced by anthropogenic emissions of carbon

  11. A Computational Study of Icing Effects on the Performance of an S-Duct Inlet

    E-Print Network [OSTI]

    Jin, Wonjin

    2009-01-01T23:59:59.000Z

    - CFL Courant-Friedrichs-Levy or Courant number - CPU Central processing unit - DC(?) Total pressure distortion coefficient... accretion on airfoils aimed at quantifying the lift, drag, and aerodynamic stability of iced aircraft wings. However, Venkataramani, et al.[16] were primarily concerned with the mass rate of ice accretion on aircraft engine stator and rotor blade...

  12. ICE Pulse Oximeter Smart Alarm App Requirements

    E-Print Network [OSTI]

    Huth, Michael

    ICE Pulse Oximeter Smart Alarm App Requirements 6 March 2012 Revision 0 for an Integrated Clinical Environment (ICE) pulse oximetry monitoring app that provides.2 References [Purpose: List all ICE standards, and other standards and references

  13. ICE Raids: Compounding Production, Contradiction, and Capitalism

    E-Print Network [OSTI]

    Reas, Elizabeth I

    2009-01-01T23:59:59.000Z

    is just a cheap way of boosting ICE ‘criminal alien’ arrestRegardless of whether or not ICE is motivated by maintainingWorkers in America: Factories and ICE Raids Produce Citizens

  14. The ice sheet model The polythermal ice sheet

    E-Print Network [OSTI]

    Calov, Reinhard

    with a temperature at the pressure melting point, the latter being considered as a bi- nary mixture of ice and small a year. Sediment Sliding The sliding velocity over sediment reads which applies if the basal ice Hudson Bay and Hudson Strait has become temperate (see Figure 4d,e), fast basal sliding appears leading

  15. VOLUME 86, NUMBER 24 P H Y S I C A L R E V I E W L E T T E R S 11 JUNE 2001 Acoustic Crystallization and Heterogeneous Nucleation

    E-Print Network [OSTI]

    Caupin, Frédéric

    ever observed that a high- intensity sound wave traveling in a liquid can crystallize this liquid to the speed of sound). We believe that it is the ability of helium crystals to grow at very high speed which pressure, the sound velocity is 366.3 m s in the liquid phase [9], so that the acoustic wavelength is 360

  16. Therapeutic Hypothermia: Protective Cooling Using Medical Ice...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Therapeutic Hypothermia: Protective Cooling Using Medical Ice Slurry Technology available for licensing: Proprietary method and equipment for making an ice slurry coolant to induce...

  17. Sandia National Laboratories: critical marginal ice zone

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    marginal ice zone NASA Award for Marginal Ice Zone Observations and Process Experiment (MIZOPEX) On February 24, 2015, in Analysis, Climate, Modeling & Analysis, Monitoring, News,...

  18. Sandia National Laboratories: Marginal Ice Zone Observations...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Marginal Ice Zone Observations and Processes Experiment mission Sierra Unmanned Aerial Vehicle to Begin Flights Over Arctic Sea Ice On July 25, 2013, in Climate, Customers &...

  19. Sandia National Laboratories: Arctic sea ice

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Arctic sea ice Sierra Unmanned Aerial Vehicle to Begin Flights Over Arctic Sea Ice On July 25, 2013, in Climate, Customers & Partners, Global, Monitoring, News, News & Events,...

  20. ARM - Ice Cores

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006Datastreamstwrcam40m DocumentationJanuary 9, 2009 [Events, FeatureListGeneralPastIce Cores Outreach Home Room

  1. ARM - Measurement - Ice nuclei

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow,ice particleSize Distributiontypes ARMnuclei

  2. Dynamics of ice shelf rift propagation and iceberg calving inferred from geodetic and seismic observations

    E-Print Network [OSTI]

    Bassis, Jeremy N.

    2007-01-01T23:59:59.000Z

    2. Ice Shelves . . . . . . . . . . . . . . . . .5. Ice Rheology . . . . . . . . . . . . . 6.vi Calving Glaciers and Ice

  3. Polarization dependence of radiowave propagation through Antarctic ice

    E-Print Network [OSTI]

    Dave Z. Besson

    2008-03-30T23:59:59.000Z

    Using a bistatic radar system on the ice surface, we have studied radiofrequency reflections off internal layers in Antarctic ice at the South Pole. In our measurement, the total propagation time of ~ns-duration, vertically broadcast radio signals, as a function of polarization axis in the horizontal plane, provides a direct probe of the geometry-dependence of the ice permittivity to depths of 1--2 km. Previous studies in East Antarctica have interpreted the measured azimuthal dependence of reflected signals as evidence for birefringent-induced interference effects, which are proposed to result from preferred alignment of the crystal orientation fabric (COF) axis. To the extent that COF alignment results from the bulk flow of ice across the Antarctic continent, we would expect a measurable birefringent asymmetry at South Pole, as well. Although we also observe clear dependence of reflected amplitude on polarization angle in our measurements, we do not observe direct evidence for birefringent-induced time-delay effects at the level of 0.1 parts per mille.

  4. Modelling the viscoplastic behavior and the heterogeneous intracrystalline deformation of columnar ice polycrystals

    SciTech Connect (OSTI)

    Lebensohn, Ricardo A [Los Alamos National Laboratory; Montagnat, Maurine [LGGE (FRANCE); Mansuy, Philippe [MICHELIN (FRANCE); Duval, Paul [LGGE (FRANCE); Philip, A [LGGE (FRANCE)

    2008-01-01T23:59:59.000Z

    A full-field formulation based on Fast Fourier Transforms (FFT) has been adapted and used to predict the micromechanical fields that develop in columnar Ih ice polycrystals deforming in compression by dislocation creep. The predicted intragranular mechanical fields are in qualitative good agreement with experimental observations, in particular those involving the formation of shear and kink bands. These localization bands are associated with the large internal stresses that develop during creep in such anisotropic material, and their location, intensity, morphology and extension are found to depend strongly on the crystallographic orientation of the grains and on their interaction with neighbor crystals. The predictions of the model are also discussed in relation with the deformation of columnar sea and lake ice, and with the mechanical behavior of granular ice of glaciers and polar ice sheets, as well.

  5. Global simulations of ice nucleation and ice supersaturation with an improved cloud scheme in the Community

    E-Print Network [OSTI]

    Gettelman, Andrew

    and supersaturation in CAM. The new model is able to reproduce field observations of ice mass and mixed phase cloud are sensitive to the parameterization of ice clouds. These results indicate that ice clouds are potentiallyGlobal simulations of ice nucleation and ice supersaturation with an improved cloud scheme

  6. Assimilation of Ice Concentration in an IceOcean Model R. W. LINDSAY AND J. ZHANG

    E-Print Network [OSTI]

    Zhang, Jinlun

    are now available to determine the ice drift velocity. In addition, the drift of the pack ice can CoAssimilation of Ice Concentration in an Ice­Ocean Model R. W. LINDSAY AND J. ZHANG Polar Science October 2004, in final form 27 June 2005) ABSTRACT Ice concentration is a critical parameter of the polar

  7. Sea-ice thickness measurement based on the dispersion of ice swell

    E-Print Network [OSTI]

    -year pack ice, although other char- acteristics (Young's modulus, shear modulus, and Poisson coefficientSea-ice thickness measurement based on the dispersion of ice swell David Marsana) ISTerre, CNRS propagating in the Arctic sea ice cover is exploited in order to locally measure the ice thickness

  8. Impact of underwater-ice evolution on Arctic summer sea ice

    E-Print Network [OSTI]

    Worster, M. Grae

    Impact of underwater-ice evolution on Arctic summer sea ice Dirk Notz,1,4 Miles G. McPhee,2 M. Grae the simultaneous growth and ablation of a layer of ice between an under-ice melt pond and the underlying ocean. Such ``false bottoms'' are the only significant source of ice formation in the Arctic during summer. Analytical

  9. Electrical properties of saline ices and ice-silicate mixtures: geophysical and astrobiological consequences (Invited)

    E-Print Network [OSTI]

    Stillman, David E.

    MR22A-05 Electrical properties of saline ices and ice-silicate mixtures: geophysical) electrical-properties measurements of laboratory- produced saline ice, salt hydrates, and ice-silicate cutoff. In ice-silicate mixtures, brine channels are evident above the eutectic temperature only when

  10. 2011-12 PROSPECTUS2011-12 PROSPECTUS WESLEYAN MEN'S ICE HOCKEYWESLEYAN MEN'S ICE HOCKEY

    E-Print Network [OSTI]

    Devoto, Stephen H.

    - ponents in its inaugural season. Former bench boss Dave Snyder, in whose honor the Wesleyan ice rink2011-12 PROSPECTUS2011-12 PROSPECTUS WESLEYAN MEN'S ICE HOCKEYWESLEYAN MEN'S ICE HOCKEY #12....................................Chris Potter/Jeff Gilarde Men's Ice Hockey..............Chris Potter Women's Ice Hockey.........Jodi Mc

  11. Mathematics of Sea Ice K. M. Golden

    E-Print Network [OSTI]

    Golden, Kenneth M.

    , the sharp decline of the summer Arc- tic sea ice pack is probably the most dramatic. For example, the area and 1990's. While global climate models generally predict de- clines in the polar sea ice packs over the 21, such as the growth and decay of seasonal ice, the evolu- tion of ice pack reflectance, and biomass build

  12. 4, 709732, 2007 Ice-shelf ocean

    E-Print Network [OSTI]

    Boyer, Edmond

    OSD 4, 709­732, 2007 Ice-shelf ­ ocean interactions at Fimbul Ice Shelf M. R. Price Title Page published in Ocean Science Discussions are under open-access review for the journal Ocean Science Ice-shelf ­ ocean interactions at Fimbul Ice Shelf, Antarctica from oxygen isotope ratio measurements M. R. Price 1

  13. Climate Change and Variability Lake Ice, Fishes

    E-Print Network [OSTI]

    Sheridan, Jennifer

    #12;Climate Change and Variability Lake Ice, Fishes and Water Levels John J. Magnuson Center to everything else." #12;The Invisible Present The Invisible Place Magnuson 2006 #12;Ice-on Day 2007 Peter W. Schmitz Photo Local Lake Mendota #12;Ice Breakup 2010 Lake Mendota March 20 #12;March 21 Ice Breakup 2010

  14. Radiative sensitivities of tropical anvils to small ice crystals

    E-Print Network [OSTI]

    Zender, Charles S.; Kiehl, J. T.

    2012-01-01T23:59:59.000Z

    Paltridge, G. W. , and C. M. R. Platt, Aircraft measurementseld, A. J . , and C. M. R. Platt, A parameterization of the50% by mass) [Heyms?eld and Platt, 1984, hereinafter HP84].

  15. Radiative sensitivities of tropical anvils to small ice crystals

    E-Print Network [OSTI]

    Zender, Charles S.; Kiehl, J. T.

    2012-01-01T23:59:59.000Z

    Jr. , Water budget of mesoscale convective system in theJr. , The contribution of mesoscale motions to the mass andpresence of a gentle mesoscale vertical updraft to supply

  16. 2 Light Scattering and Absorption by Nonspherical Ice Crystals

    E-Print Network [OSTI]

    Liou, K. N.

    % to 25%, but recent analysis using the 15-µm CO2 satellite channels has shown that their occurrence significantly from low and middle clouds in terms of their ra- diative properties. High cirrus clouds reflect in the polar regions because of low temperatures. The global cirrus cover has been estimated to be about 20

  17. Single Particle Database of Natural Ice Crystals: Dimensions

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz9Morgan McCorkleSingin' in the Rain NewsSingle

  18. Magnetic charge crystals imaged in artificial spin ice

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated Codes |IsLove Your Home and It'll Love YouTokamak| NationalMagneticMagnetic

  19. Impact of Ice Crystal Roughness on Satellite Retrieved Cloud Properties

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School footballHydrogenIT |HotImpact of Generator Flexibility

  20. Dynamics of CO in Amorphous Water Ice Environments

    E-Print Network [OSTI]

    Karssemeijer, L J; van Hemert, M C; van der Avoird, A; Allodi, M A; Blake, G A; Cuppen, H M

    2013-01-01T23:59:59.000Z

    The long-timescale behavior of adsorbed carbon monoxide on the surface of amorphous water ice is studied under dense cloud conditions by means of off-lattice, on-the-fly, kinetic Monte Carlo simula- tions. It is found that the CO mobility is strongly influenced by the morphology of the ice substrate. Nanopores on the surface provide strong binding sites which can effectively immobilize the adsorbates at low coverage. As the coverage increases, these strong binding sites are gradually occupied leav- ing a number of admolecules with the ability to diffuse over the surface. Binding energies, and the energy barrier for diffusion are extracted for various coverages. Additionally, the mobility of CO is determined from isothermal desorption experiments. Reasonable agreement on the diffusivity of CO is found with the simulations. Analysis of the 2152 cm$^{-1}$, polar CO band supports the computational findings that the pores in the water ice provide the strongest binding sites and dominate diffusion at low temperatur...

  1. Neglecting ice-atmosphere interactions underestimates ice sheet melt in millennial-scale deglaciation simulations

    E-Print Network [OSTI]

    Pritchard, M. S.; Bush, A. B.; Marshall, S. J.

    2008-01-01T23:59:59.000Z

    Laurentide and Innutian ice sheets during the Last Glacialclimate of the laurentide ice sheet at the LGM, J. Clim. ,1958), The flow law of ice: A discussion of the assumptions

  2. An experimental and theoretical study of the ice accretion process during artificial and natural icing conditions

    E-Print Network [OSTI]

    Kirby, Mark Samuel

    1986-01-01T23:59:59.000Z

    Real-time measurements of ice growth during artificial and natural icing conditions were conducted using an ultrasonic pulse-echo technique. This technique allows ice thickness to be measured with an accuracy of ?0.5 mm; ...

  3. Journal of Glaciology, Vol. 56, No. 199, 2010 805 Enhancement factors for grounded ice and ice shelves inferred

    E-Print Network [OSTI]

    Gagliardini, Olivier

    shelves inferred from an anisotropic ice-flow model Ying MA,1 Olivier GAGLIARDINI,1 Catherine RITZ,1 on the actual state of stress and strain rate. Within an ice sheet, grounded-ice parts and ice shelves have of ice anisotropy on the flow of grounded ice and ice shelves. For this purpose, a full

  4. Journal of Glaciology, Vol. 00, No. 000, 0000 1 Enhancement factors for grounded ice and ice shelves1

    E-Print Network [OSTI]

    Durand, Gaël

    shelves1 inferred from an anisotropic ice flow model2 Ying MA,1 Olivier GAGLIARDINI,1 Catherine RITZ,1 of stress and strain-rate. Within an ice sheet, grounded ice parts and ice shelves have com-11 pletely of ice anisotropy on the flow of grounded ice and ice shelves. To this pur-14 pose, a full

  5. amorphous water ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    artificial and natural icing conditions MIT - DSpace Summary: Real-time measurements of ice growth during artificial and natural icing conditions were conducted using an...

  6. amery ice shelf: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    artificial and natural icing conditions MIT - DSpace Summary: Real-time measurements of ice growth during artificial and natural icing conditions were conducted using an...

  7. amorphous ice transition: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    artificial and natural icing conditions MIT - DSpace Summary: Real-time measurements of ice growth during artificial and natural icing conditions were conducted using an...

  8. antarctica larsen ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    artificial and natural icing conditions MIT - DSpace Summary: Real-time measurements of ice growth during artificial and natural icing conditions were conducted using an...

  9. alpine deep ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    artificial and natural icing conditions MIT - DSpace Summary: Real-time measurements of ice growth during artificial and natural icing conditions were conducted using an...

  10. airborne ice sounding: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    artificial and natural icing conditions MIT - DSpace Summary: Real-time measurements of ice growth during artificial and natural icing conditions were conducted using an...

  11. No Confinement Needed: Observation of a Metastable Hydrophobic Wetting Two-Layer Ice on Graphene

    SciTech Connect (OSTI)

    Kimmel, Gregory A.; Matthiesen, Jesper; Baer, Marcel; Mundy, Christopher J.; Petrik, Nikolay G.; Smith, R. Scott; Dohnalek, Zdenek; Kay, Bruce D.

    2009-09-09T23:59:59.000Z

    The structure of water at interfaces is crucial for processes ranging from photocatalysis to protein folding. Here, we investigate the structure and lattice dynamics of two-layer crystalline ice films grown on a hydrophobic substrate - graphene on Pt(111) - with low energy electron diffraction, reflection-absorption infrared spectroscopy, rare-gas adsorption/desorption, and ab-initio molecular dynamics. Unlike hexagonal ice, which consists of stacks of puckered hexagonal "bilayers", this new ice polymorph consists of two flat hexagonal sheets of water molecules in which the hexagons in each sheet are stacked directly on top of each other. Such two-layer ices have been predicted for water confined between hydrophobic slits, but not previously observed. Our results show that the two-layer ice forms even at zero pressure at a single hydrophobic interface by maximizing the number of hydrogen bonds at the expense of adopting a non-tetrahedral geometry with weakened bonds.

  12. FINAL REPORT FOR THE DOE/ARM PROJECT TITLED Representation of the Microphysical and Radiative Properties of Ice Clouds in SCMs and GCMs

    SciTech Connect (OSTI)

    Mitchell, David L.

    2005-08-08T23:59:59.000Z

    The broad goal of this research is to improve climate prediction through better representation of cirrus cloud microphysical and radiative properties in global climate models (GCMs). Clouds still represent the greatest source of uncertainty in climate prediction, and the representation of ice clouds is considerably more challenging than liquid water clouds. While about 40% of cloud condensate may be in the form of ice by some estimates, there have been no credible means of representing the ice particle size distribution and mass removal rates from ice clouds in GCMs. Both factors introduce large uncertainties regarding the global net flux, the latter factor alone producing a change of 10 W/m2 in the global net flux due to plausible changes in effective ice particle fallspeed. In addition, the radiative properties of ice crystals themselves are in question. This research provides GCMs with a credible means of representing the full (bimodal) ice particle size distribution (PSD) in ice clouds, including estimates of the small crystal (D < 65 microns) mode of the PSD. It also provides realistic estimates of mass sedimentation rates from ice clouds, which have a strong impact on their ice contents and radiative properties. This can be done through proper analysis of ice cloud microphysical data from ARM and other field campaigns. In addition, this research tests the ice cloud radiation treatment developed under two previous ARM projects by comparing it against laboratory measurements of ice cloud extinction efficiency and by comparing it with explicit theoretical calculations of ice crystal optical properties. The outcome of this project includes two PSD schemes for ice clouds; one appropriate for mid-latitude cirrus clouds and another for tropical anvil cirrus. Cloud temperature and ice water content (IWC) are the inputs for these PSD schemes, which are based on numerous PSD observations. The temperature dependence of the small crystal mode of the PSD for tropical anvils is opposite to that of mid-latitude cirrus, and this results in very different radiative properties for these two types of cirrus at temperatures less than about 50 C for a given ice water path. In addition, the representative PSD fall velocity is strongly influenced by the small crystal mode, and for temperatures less than 52 C, this fall velocity for mid-latitude cirrus is 2-8 times greater than for tropical anvil cirrus. Finally, the treatment of ice cloud optical properties was found to agree with laboratory measurements and exact theory within 15% for any given wavelength, PSD and ice particle shape. This treatment is analytical, formulated in terms of the PSD and ice particle shape properties. It thus provides the means for explicitly coupling the ice cloud microphysical and radiative properties, and can treat any combination of ice particle shape. It is very inexpensive regarding computer time. When these three deliverables were incorporated into the GCM at the National Center for Atmospheric Research (NCAR) under another project, it was found that the sunlight reflected and the amount of upwelling heat absorbed by cirrus clouds depended strongly on the PSD scheme used (i.e. mid-latitude or tropical anvil). This was largely due to the fall velocities associated with the two PSD schemes, although the PSD shape was also important.

  13. The Microscopic Features of Heterogeneous Ice Nucleation May Affect the Macroscopic Morphology of Atmospheric Ice Crystals

    E-Print Network [OSTI]

    Alavi, Ali

    Michaelides1, 2 1) Thomas Young Centre and Department of Chemistry, University College London, London WC1E 6BT, U.K. 2) London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1

  14. Vapor deposition of water on graphitic surfaces: Formation of amorphous ice, bilayer ice, ice I, and liquid water

    SciTech Connect (OSTI)

    Lupi, Laura; Kastelowitz, Noah; Molinero, Valeria, E-mail: Valeria.Molinero@utah.edu [Department of Chemistry, The University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850 (United States)

    2014-11-14T23:59:59.000Z

    Carbonaceous surfaces are a major source of atmospheric particles and could play an important role in the formation of ice. Here we investigate through molecular simulations the stability, metastability, and molecular pathways of deposition of amorphous ice, bilayer ice, and ice I from water vapor on graphitic and atomless Lennard-Jones surfaces as a function of temperature. We find that bilayer ice is the most stable ice polymorph for small cluster sizes, nevertheless it can grow metastable well above its region of thermodynamic stability. In agreement with experiments, the simulations predict that on increasing temperature the outcome of water deposition is amorphous ice, bilayer ice, ice I, and liquid water. The deposition nucleation of bilayer ice and ice I is preceded by the formation of small liquid clusters, which have two wetting states: bilayer pancake-like (wetting) at small cluster size and droplet-like (non-wetting) at larger cluster size. The wetting state of liquid clusters determines which ice polymorph is nucleated: bilayer ice nucleates from wetting bilayer liquid clusters and ice I from non-wetting liquid clusters. The maximum temperature for nucleation of bilayer ice on flat surfaces, T{sub B}{sup max} is given by the maximum temperature for which liquid water clusters reach the equilibrium melting line of bilayer ice as wetting bilayer clusters. Increasing water-surface attraction stabilizes the pancake-like wetting state of liquid clusters leading to larger T{sub B}{sup max} for the flat non-hydrogen bonding surfaces of this study. The findings of this study should be of relevance for the understanding of ice formation by deposition mode on carbonaceous atmospheric particles, including soot.

  15. NOAA Technical Memorandum GLERL-135 Great Lakes Ice Cover Climatology

    E-Print Network [OSTI]

    ____________________________________________________________________________ Great Lakes Ice Cover Climatology Update: Winters 2003, 2004, and 2005 Raymond A. Assel NOAA, Great..................................................................................................6 DATES OF FIRST (LAST) ICE AND ICE DURATION. .............................................................7 SEASONAL PROGRESSION OF ICE COVER

  16. Ross Ice Shelf in situ radio-frequency ice attenuation

    E-Print Network [OSTI]

    Taylor Barrella; Steven Barwick; David Saltzberg

    2012-05-01T23:59:59.000Z

    We have measured the in situ average electric field attenuation length for radio-frequency signals broadcast vertically through the Ross Ice Shelf. We chose a location, Moore Embayment, south of Minna Bluff, known for its high reflectivity at the ice-sea interface. We confirmed specular reflection and used the return pulses to measure the average attenuation length from 75-1250 MHz over the round-trip distance of 1155 m. We find the average electric field attenuation length to vary from 500 m at 75 MHz to 300 m at 1250 MHz, with an experimental uncertainty of 55 to 15 m. We discuss the implications for neutrino telescopes that use the radio technique and include the Ross Ice Shelf as part of their sensitive volume.

  17. Ice-condenser aerosol tests

    SciTech Connect (OSTI)

    Ligotke, M.W.; Eschbach, E.J.; Winegardner, W.K. (Pacific Northwest Lab., Richland, WA (United States))

    1991-09-01T23:59:59.000Z

    This report presents the results of an experimental investigation of aerosol particle transport and capture using a full-scale height and reduced-scale cross section test facility based on the design of the ice compartment of a pressurized water reactor (PWR) ice-condenser containment system. Results of 38 tests included thermal-hydraulic as well as aerosol particle data. Particle retention in the test section was greatly influenced by thermal-hydraulic and aerosol test parameters. Test-average decontamination factor (DF) ranged between 1.0 and 36 (retentions between {approximately}0 and 97.2%). The measured test-average particle retentions for tests without and with ice and steam ranged between DF = 1.0 and 2.2 and DF = 2.4 and 36, respectively. In order to apparent importance, parameters that caused particle retention in the test section in the presence of ice were steam mole fraction (SMF), noncondensible gas flow rate (residence time), particle solubility, and inlet particle size. Ice-basket section noncondensible flows greater than 0.1 m{sup 3}/s resulted in stable thermal stratification whereas flows less than 0.1 m{sup 3}/s resulted in thermal behavior termed meandering with frequent temperature crossovers between flow channels. 10 refs., 66 figs., 16 tabs.

  18. Optomechanical Crystals

    E-Print Network [OSTI]

    Eichenfield, Matt; Camacho, Ryan M; Vahala, Kerry J; Painter, Oskar

    2009-01-01T23:59:59.000Z

    Structured, periodic optical materials can be used to form photonic crystals capable of dispersing, routing, and trapping light. A similar phenomena in periodic elastic structures can be used to manipulate mechanical vibrations. Here we present the design and experimental realization of strongly coupled optical and mechanical modes in a planar, periodic nanostructure on a silicon chip. 200-Terahertz photons are co-localized with mechanical modes of Gigahertz frequency and 100-femtogram mass. The effective coupling length, which describes the strength of the photon-phonon interaction, is as small as 2.9 microns, which, together with minute oscillator mass, allows all-optical actuation and transduction of nanomechanical motion with near quantum-limited sensitivity. Optomechanical crystals have many potential applications, from RF-over-optical communication to the study of quantum effects in mesoscopic mechanical systems.

  19. A physically based parameterization of gravity drainage for sea-ice modelling

    E-Print Network [OSTI]

    Rees Jones, David W.; Worster, M. Grae

    2014-09-02T23:59:59.000Z

    an integral aspect of any cou- pled climate model [Gent , 2012]. Although only a few me- ters thick, sea ice plays a significant role in the coupling between ocean and atmosphere because it reflects a higher proportion of solar radiation than open water... suspect the latter is a result of our neglect of solar radiation, and brine expulsion, which would transport salt downwards within the ice, increasing the solid fraction in the upper ice and thereby reducing the permeabil- ity and local Rayleigh number. We...

  20. Heavy ion irradiation of crystalline water ice

    E-Print Network [OSTI]

    Dartois, E; Boduch, P; Brunetto, R; Chabot, M; Domaracka, A; Ding, J J; Kamalou, O; Lv, X Y; Rothard, H; da Silveira, E F; Thomas, J C

    2015-01-01T23:59:59.000Z

    Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic ...

  1. Thermal Storage with Ice Harvesting Systems

    E-Print Network [OSTI]

    Knebel, D. E.

    1986-01-01T23:59:59.000Z

    Application of Harvesting Ice Storage Systems. Thermal storage systems are becoming widely accepted techniques for utility load management. This paper discusses the principles of ice harvesting equipment and their application to the multi...

  2. Rubber friction on ice and snow surfaces 

    E-Print Network [OSTI]

    Skouvaklis, Gerasimos

    2011-06-28T23:59:59.000Z

    The friction of rubber on ice and snow surfaces is complex. Deeper scientific understanding is important for optimising performance of tyres in winter. Rubber, ice and snow systems exhibit frictional behaviour which ...

  3. Developing Great Lakes Ice Model (GLIM) using CIOM (Coupled Ice-Ocean Model) in Lake Erie

    E-Print Network [OSTI]

    Developing Great Lakes Ice Model (GLIM) using CIOM (Coupled Ice- Ocean Model) in Lake Erie Primary of the ice-ocean models, assistance with development of project reports and scientific presentations will first start the implementation of the CIOM in Lake Erie, assemble satellite observations of ice cover

  4. Ice Stream C slowdown is not stabilizing West Antarctic Ice Sheet S Anandakrishnan RB Alleyy

    E-Print Network [OSTI]

    Jacobel, Robert W.

    Ice Stream C slowdown is not stabilizing West Antarctic Ice Sheet S Anandakrishnan RB Alleyy RW Jacobelz H Conwayx March 24, 1999 Abstract Changes in the flow of ice stream C likely indicate a continuing part of ice stream C, West Antarctica largely stagnated over the last few centuries, while upglacier

  5. Quenched by ice: Transient grating measurements of vibronic dynamics in bromine-doped ice

    E-Print Network [OSTI]

    Apkarian, V. Ara

    Quenched by ice: Transient grating measurements of vibronic dynamics in bromine-doped ice I. U April 2006; published online 25 May 2006 In both water and in ice, the absorption spectra of bromine of the trapped molecule in its electronic B 3 0u state in ice. Independent of the initial excitation energy

  6. New study details glacier ice loss following ice shelf July 25, 2011

    E-Print Network [OSTI]

    Cambridge, University of

    of several ice shelves in Antarctica led to acceleration of the glaciers that feed into them. CombiningNew study details glacier ice loss following ice shelf collapse July 25, 2011 Contact: Anthony Lane further demonstrates how important ice shelves are to Antarctic glaciers.' Shuman is lead author

  7. 115GLACIERS AND ICE CAPSCHAPTER 6B Glaciers and Ice Caps

    E-Print Network [OSTI]

    Fountain, Andrew G.

    115GLACIERS AND ICE CAPSCHAPTER 6B 6B Glaciers and Ice Caps Michael Zemp (lead author, Department of Sciences, China) #12;116 GLOBAL OUTLOOK FOR ICE AND SNOW Summary Glaciers and ice caps are among the most hazards. Because they are close to the melting point and react strongly to climate change, glaciers

  8. Homogeneous ice nucleation evaluated for several water models

    E-Print Network [OSTI]

    J. R. Espinosa; E. Sanz; C. Valeriani; C. Vega

    2014-11-25T23:59:59.000Z

    In this work, we evaluate by means of computer simulations the rate for ice homogeneous nucleation for several water models such as TIP4P, TIP4P/2005,TIP4P/ICE, and mW (following the same procedure as in Sanz et al. [J. Am. Chem. Soc.135, 15008 (2013)]) in a broad temperature range. We estimate the ice-liquid interfacial free-energy, and conclude that for all water models {\\gamma} decreases as the temperature decreases. Extrapolating our results to the melting temperature, we obtain a value of the interfacial free-energy between 25 and 32 mN/m in reasonable agreement with the reported experimental values. Moreover, we observe that the values of {\\gamma} depend on the chosen water model and this is a key factor when numerically evaluating nucleation rates, given that the kinetic prefactor is quite similar for all water models with the exception of the mW (due to the absence of hydrogens). Somewhat surprisingly the estimates of the nucleation rates found in this work for TIP4P/2005 are slightly higher than those of the mW model, even though the former has explicit hydrogens. Our results suggest that it may be possible to observe in computer simulations spontaneous crystallization of TIP4P/2005 at about 60 K below the melting point.

  9. Insights into the crystal chemistry of Earth materials rendered...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    density between bonded pairs of atoms for a relatively large number of oxide and silicate crystals and siloxane molecules. The distribution of the electron density shows that...

  10. Formation and character of an ancient 19-m ice cover and underlying trapped brine in an ``ice-sealed'' east

    E-Print Network [OSTI]

    Priscu, John C.

    Formation and character of an ancient 19-m ice cover and underlying trapped brine in an ``ice bed year-round. New ice-core analysis and tempera- ture data show that beneath 19 m of ice is a water°C. The ice cover thickens at both its base and surface, sealing concentrated brine beneath. The ice

  11. Ice Cream in a Bag Ingredients

    E-Print Network [OSTI]

    Liskiewicz, Maciej

    Ice Cream in a Bag Ingredients: 1 tablespoon sugar 1/4 teaspoon vanilla extract 2 tablespoons soft fruit 1/2 cup skim milk For the freezer bag; not to be eaten: 1/3 cup rock salt Ice cubes Directions 1. Open a gallon size plastic bag. Add rock salt and fill half way up with ice. Shake to mix the salt

  12. 3, 9991020, 2007 Summer sea ice

    E-Print Network [OSTI]

    Boyer, Edmond

    CPD 3, 999­1020, 2007 Summer sea ice during the early Holocene H. Goosse et al. Title Page Abstract on the early Holocene climate constrains the summer sea ice projections for the 21st century H. Goosse, E #12;CPD 3, 999­1020, 2007 Summer sea ice during the early Holocene H. Goosse et al. Title Page

  13. 2, 879921, 2006 Ice-sheet evolution

    E-Print Network [OSTI]

    Boyer, Edmond

    CPD 2, 879­921, 2006 Ice-sheet evolution during the last climatic cycle S. Charbit et al. Title reconstructions of the Northern Hemisphere ice sheets through the last glacial-interglacial cycle S. Charbit1 , C­921, 2006 Ice-sheet evolution during the last climatic cycle S. Charbit et al. Title Page Abstract

  14. Surface Impedance Tomography for Antarctic Sea Ice

    E-Print Network [OSTI]

    Golden, Kenneth M.

    Surface Impedance Tomography for Antarctic Sea Ice C. Sampsona , K. M. Goldena , A. Gullya , A. P, Australia Abstract During the 2007 SIPEX expedition in pack ice off the coast of East Antarctica, we measured the electrical conductivity of sea ice via surface impedance tomography. Resistance data from

  15. 8, 87438771, 2008 Inhibition of ice

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 8, 8743­8771, 2008 Inhibition of ice crystallisation B. J. Murray Title Page Abstract Chemistry and Physics Discussions Inhibition of ice crystallisation in highly viscous aqueous organic acid­8771, 2008 Inhibition of ice crystallisation B. J. Murray Title Page Abstract Introduction Conclusions

  16. 5, 37233745, 2005 characteristics of ice

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 5, 3723­3745, 2005 Chemical characteristics of ice nuclei in anvil cirrus clouds C. H. Twohy and Physics Discussions Chemical characteristics of ice residual nuclei in anvil cirrus clouds: evidence for homogeneous and heterogeneous ice formation C. H. Twohy 1 and M. R. Poellot 2 1 College of Oceanic

  17. The convective desalination of sea ice

    E-Print Network [OSTI]

    Rees Jones, David

    2014-07-01T23:59:59.000Z

    containing both liquid brine and solid (pure water) ice. Frad is the flux of penetrating solar radiation. Thus the thermal properties of sea ice are composed of those of the solid and liquid phases that make up sea ice. Fixed-salinity models used in older...

  18. IceCube Project Monthly Report Accomplishments

    E-Print Network [OSTI]

    Saffman, Mark

    staff from UW, IceCube collaborators, and Raytheon. · Conducted a Quarterly Status Meeting at UW-loaded schedule for on-ice activities that is coordinated with the Raytheon on-ice schedules. Construction Cost accurate application of escalation rates and revisions to actual cost data. Raytheon earned value data

  19. Global Land Ice Measurements

    E-Print Network [OSTI]

    other physical way, and transmission or information storage and retrieval, electronic adaptation Number: 2014943116 Springer-Verlag Berlin Heidelberg 2014 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, speci cally the rights

  20. Microwave emissivity of fresh water ice--Lake ice and Antarctic ice pack--Radiative transfer simulations versus satellite radiances

    E-Print Network [OSTI]

    Mills, Peter

    2012-01-01T23:59:59.000Z

    Microwave emissivity models of sea ice are poorly validated empirically. Typical validation studies involve using averaged or stereotyped profiles of ice parameters against averaged radiance measurements. Measurement sites are rarely matched and even less often point-by-point. Because of saline content, complex permittivity of sea ice is highly variable and difficult to predict. Therefore, to check the validity of a typical, plane-parallel, radiative-transfer-based ice emissivity model, we apply it to fresh water ice instead of salt-water ice. Radiance simulations for lake ice are compared with measurements over Lake Superior from the Advanced Microwave Scanning Radiometer on EOS (AMSR-E). AMSR-E measurements are also collected over Antarctic icepack. For each pixel, a thermodynamic model is driven by four years of European Center for Medium Range Weather Forecasts (ECMWF) reanalysis data and the resulting temperature profiles used to drive the emissivity model. The results suggest that the relatively simple ...

  1. Modeling the Jovian subnebula: II - Composition of regular satellites ices

    E-Print Network [OSTI]

    Olivier Mousis; Yann Alibert

    2005-10-28T23:59:59.000Z

    We use the evolutionary turbulent model of Jupiter's subnebula described by Alibert et al. (2005a) to constrain the composition of ices incorporated in its regular icy satellites. We consider CO2, CO, CH4, N2, NH3, H2S, Ar, Kr, and Xe as the major volatile species existing in the gas-phase of the solar nebula. All these volatile species, except CO2 which crystallized as a pure condensate, are assumed to be trapped by H2O to form hydrates or clathrate hydrates in the solar nebula. Once condensed, these ices were incorporated into the growing planetesimals produced in the feeding zone of proto-Jupiter. Some of these solids then flowed from the solar nebula to the subnebula, and may have been accreted by the forming Jovian regular satellites. We show that ices embedded in solids entering at early epochs into the Jovian subdisk were all vaporized. This leads us to consider two different scenarios of regular icy satellites formation in order to estimate the composition of the ices they contain. In the first scenario, icy satellites were accreted from planetesimals that have been produced in Jupiter's feeding zone without further vaporization, whereas, in the second scenario, icy satellites were accreted from planetesimals produced in the Jovian subnebula. In this latter case, we study the evolution of carbon and nitrogen gas-phase chemistries in the Jovian subnebula and we show that the conversions of N2 to NH3, of CO to CO2, and of CO to CH4 were all inhibited in the major part of the subdisk. Finally, we assess the mass abundances of the major volatile species with respect to H2O in the interiors of the Jovian regular icy satellites. Our results are then compatible with the detection of CO2 on the surfaces of Callisto and Ganymede and with the presence of NH3 envisaged in subsurface oceans within Ganymede and Callisto.

  2. Modeling Interfacial Liquid Layers in Environmental Ices SUPPLEMENTARY MATERIAL

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    Symbol Quantity ice wf Fugacity of pure ice brine wf^ Fugacity of water in brine layer vap wf Fugacity of water in vapor space above ice wf Fugacity of pure liquid water wx Mole fraction of water in brine layer ice wH Enthalpy of ice at T, P 0,ice wH Enthalpy of ice at reference state brine wH Partial molar

  3. A comprehensive laboratory study on the immersion freezing behavior of illite NX particles: a comparison of 17 ice nucleation measurement techniques

    SciTech Connect (OSTI)

    Hiranuma, Naruki; Augustin-Bauditz, Stefanie; Bingemer, Heinz; Budke, Carsten; Curtius, J.; Danielczok, Anja; Diehl, K.; Dreischmeier, Katharina; Ebert, Martin; Frank, F.; Hoffmann, Nadine; Kandler, Kondrad; Kiselev, Alexei; Koop, Thomas; Leisner, Thomas; Mohler, Ottmar; Nillius, Bjorn; Peckhaus, Andreas; Rose, Diana; Weinbruch, Stephan; Wex, Heike; Boose, Yvonne; DeMott, Paul J.; Hader, John D.; Hill, Thomas; Kanji, Zamin; Kulkarni, Gourihar R.; Levin, Ezra; McCluskey, Christina; Murakami, Masataka; Murray, Benjamin J.; Niedermeier, Dennis; Petters, Markus D.; O'Sullivan, Daniel; Saito, Atsushi; Schill, Gregory; Tajiri, Takuya; Tolbert, Margaret A.; Welti, Andre; Whale, Thomas; Wright, Timothy; Yamashita, Katsuya

    2015-01-01T23:59:59.000Z

    Immersion freezing is the most relevant heterogeneous ice nucleation mechanism 3 through which ice crystals are formed in mixed-phase clouds. In recent years, an increasing 4 number of laboratory experiments utilizing a variety of instruments have examined immersion 5 freezing activity of atmospherically relevant ice nucleating particles (INPs). However, an 6 inter-comparison of these laboratory results is a difficult task because investigators have used 7 different ice nucleation (IN) measurement methods to produce these results. A remaining 8 challenge is to explore the sensitivity and accuracy of these techniques and to understand how 9 the IN results are potentially influenced or biased by experimental parameters associated with 10 these techniques. 11 Within the framework of INUIT (Ice Nucleation research UnIT), we distributed an 12 illite rich sample (illite NX) as a representative surrogate for atmospheric mineral dust 13 particles to investigators to perform immersion freezing experiments using different IN 14 measurement methods and to obtain IN data as a function of particle concentration, 15 temperature (T), cooling rate and nucleation time. Seventeen measurement methods were 16 involved in the data inter-comparison. Experiments with seven instruments started with the 17 test sample pre-suspended in water before cooling, while ten other instruments employed 18 water vapor condensation onto dry-dispersed particles followed by immersion freezing. The 19 resulting comprehensive immersion freezing dataset was evaluated using the ice nucleation 20 active surface-site density (ns) to develop a representative ns(T) spectrum that spans a wide 21 temperature range (-37 °C < T < -11 °C) and covers nine orders of magnitude in ns. 22 Our inter-comparison results revealed a discrepancy between suspension and dry-23 dispersed particle measurements for this mineral dust. While the agreement was good below ~-24 26 °C, the ice nucleation activity, expressed in ns, was smaller for the wet suspended samples 25 and higher for the dry-dispersed aerosol samples between about -26 and -18 °C. Only 26 instruments making measurement techniques with wet suspended samples were able to 27 measure ice nucleation above -18 °C. A possible explanation for the deviation between -26 28 and -18 °C is discussed. In general, the seventeen immersion freezing measurement 29 techniques deviate, within the range of about 7 °C in terms of temperature, by three orders of 30 magnitude with respect to ns. In addition, we show evidence that the immersion freezing 31 efficiency (i.e., ns) of illite NX particles is relatively independent on droplet size, particle 32 mass in suspension, particle size and cooling rate during freezing. A strong temperature-33 2 dependence and weak time- and size-dependence of immersion freezing efficiency of illite-34 rich clay mineral particles enabled the ns parameterization solely as a function of temperature. 35 We also characterized the ns(T) spectra, and identified a section with a steep slope between -36 20 °C and -27 °C, where a large fraction of active sites of our test dust may trigger immersion 37 freezing. This slope was followed by a region with a gentler slope at temperatures below -27 38 °C. A multiple exponential distribution fit is expressed as ns(T) = exp(23.82 × exp(-exp(0.16 × 39 (T + 17.49))) + 1.39) based on the specific surface area and ns(T) = exp(25.75 × exp(-exp(0.13 40 × (T + 17.17))) + 3.34) based on the geometric area (ns and T in m-2 and °C, respectively). 41 These new fits, constrained by using an identical reference samples, will help to compare IN 42 measurement methods that are not included in the present study and, thereby, IN data from 43 future IN instruments.

  4. Monochromator Crystal Glitch Library

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    SSRL's Monochromator Crystal Glitch Library allows users to view glitch spectra online, list specific crystal orientations, and download PDF files of the glitch spectra. (Specialized Interface)

  5. New ice rules for nanoconfined monolayer ice from first principles

    E-Print Network [OSTI]

    Corsetti, Fabiano; Artacho, Emilio

    2015-01-01T23:59:59.000Z

    Understanding the structural tendencies of nanoconfined water is of great interest for nanoscience and biology, where nano/micro-sized objects may be separated by very few layers of water. Here we investigate the properties of ice confined to a quasi-2D monolayer by a featureless, chemically neutral potential, using density-functional theory simulations with a non-local van der Waals density functional. An ab initio random structure search reveals all the energetically competitive monolayer configurations to belong to only two of the previously-identified families, characterized by a square or honeycomb hydrogen-bonding network, respectively. From an in-depth analysis we show that the well-known ice rules for bulk ice need to be revised for the monolayer, with distinct new rules appearing for the two networks. All identified stable phases for both are found to be non-polar (but with a topologically non-trivial texture for the square) and, hence, non-ferroelectric, in contrast to the predictions of empirical f...

  6. Hydrogen ICE Vehicle Testing Activities

    SciTech Connect (OSTI)

    J. Francfort; D. Karner

    2006-04-01T23:59:59.000Z

    The Advanced Vehicle Testing Activity teamed with Electric Transportation Applications and Arizona Public Service to develop and monitor the operations of the APS Alternative Fuel (Hydrogen) Pilot Plant. The Pilot Plant provides 100% hydrogen, and hydrogen and compressed natural gas (H/CNG)-blended fuels for the evaluation of hydrogen and H/CNG internal combustion engine (ICE) vehicles in controlled and fleet testing environments. Since June 2002, twenty hydrogen and H/CNG vehicles have accumulated 300,000 test miles and 5,700 fueling events. The AVTA is part of the Department of Energy’s FreedomCAR and Vehicle Technologies Program. These testing activities are managed by the Idaho National Laboratory. This paper discusses the Pilot Plant design and monitoring, and hydrogen ICE vehicle testing methods and results.

  7. Permanent Home Number: Residential Number

    E-Print Network [OSTI]

    Viglas, Anastasios

    Permanent Home Number: Residential Number: Mobile: Please update my contact details. Signature nominated correspondence address as indicated below. Permanent Home Adress Residential Address Other Address (Must not be a PO Box) Residential Address (Must not be a PO Box) Other - Postal/Optional Address

  8. Sea Ice Enhancements to Polar WRF* Keith M. Hines1**

    E-Print Network [OSTI]

    Howat, Ian M.

    of Arctic multi-year ice is30 decreasing with more of the ice pack represented by seasonal sea iceSea Ice Enhancements to Polar WRF* Keith M. Hines1** , David H. Bromwich,1,2 , Lesheng Bai1 to6 WRF Version 3.4 include modified Noah land surface model sea ice treatment, allowing7 specified

  9. GREAT LAKES ICE COVER RaymondA. Asset'

    E-Print Network [OSTI]

    Chapter 6 GREAT LAKES ICE COVER RaymondA. Asset' ABSTRACT: Theformation of ice on the Lallrentian (~rthe Great Lakes anel local weather and climate. The (I1Inllal seasonal and ~'Patialprogression of ice Lake (Section 6.2) incillding ice thickness, the different types of iceformed, and ice classification

  10. An Ice Lithography Instrument Anpan Han 1, John Chervinsky2

    E-Print Network [OSTI]

    Page 1 An Ice Lithography Instrument Anpan Han 1, John Chervinsky2 , Daniel Branton3 , and J. A a new nano-patterning method called ice lithography, where ice is used as the resist. Water vapor. The vapor condenses, covering the sample with an amorphous layer of ice. To form a lift-off mask, ice

  11. UNIT NUMBER:

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    193 UNIT NUMBER: 197 UNIT NAME: CONCRETE RUBBLE PILE (30) REGULATORY STATUS: AOC LOCATION: Outside plant security fence, north of the plant on Big Bayou Creek on private property....

  12. FAFCO Ice Storage test report

    SciTech Connect (OSTI)

    Stovall, T.K.

    1993-11-01T23:59:59.000Z

    The Ice Storage Test Facility (ISTF) is designed to test commercial ice storage systems. FAFCO provided a storage tank equipped with coils designed for use with a secondary fluid system. The FAFCO ice storage system was tested over a wide range of operating conditions. Measured system performance during charging showed the ability to freeze the tank fully, storing from 150 to 200 ton-h. However, the charging rate showed significant variations during the latter portion of the charge cycle. During discharge cycles, the storage tank outlet temperature was strongly affected by the discharge rate and tank state of charge. The discharge capacity was dependent upon both the selected discharge rate and maximum allowable tank outlet temperature. Based on these tests, storage tank selection must depend on both charge and discharge conditions. This report describes FAFCO system performance fully under both charging and discharging conditions. While the test results reported here are accurate for the prototype 1990 FAFCO Model 200, currently available FAFCO models incorporate significant design enhancements beyond the Model 200. At least one major modification was instituted as a direct result of the ISTF tests. Such design improvements were one of EPRI`s primary goals in founding the ISTF.

  13. Measurement of South Pole ice transparency with the IceCube LED calibration system

    E-Print Network [OSTI]

    IceCube Collaboration; M. G. Aartsen; R. Abbasi; Y. Abdou; M. Ackermann; J. Adams; J. A. Aguilar; M. Ahlers; D. Altmann; J. Auffenberg; X. Bai; M. Baker; S. W. Barwick; V. Baum; R. Bay; J. J. Beatty; S. Bechet; J. Becker Tjus; K. -H. Becker; M. Bell; M. L. Benabderrahmane; S. BenZvi; J. Berdermann; P. Berghaus; D. Berley; E. Bernardini; A. Bernhard; D. Bertrand; D. Z. Besson; G. Binder; D. Bindig; M. Bissok; E. Blaufuss; J. Blumenthal; D. J. Boersma; S. Bohaichuk; C. Bohm; D. Bose; S. Böser; O. Botner; L. Brayeur; A. M. Brown; R. Bruijn; J. Brunner; S. Buitink; M. Carson; J. Casey; M. Casier; D. Chirkin; B. Christy; K. Clark; F. Clevermann; S. Cohen; D. F. Cowen; A. H. Cruz Silva; M. Danninger; J. Daughhetee; J. C. Davis; C. De Clercq; S. De Ridder; P. Desiati; M. de With; T. DeYoung; J. C. Díaz-Vélez; M. Dunkman; R. Eagan; B. Eberhardt; J. Eisch; R. W. Ellsworth; S. Euler; P. A. Evenson; O. Fadiran; A. R. Fazely; A. Fedynitch; J. Feintzeig; T. Feusels; K. Filimonov; C. Finley; T. Fischer-Wasels; S. Flis; A. Franckowiak; R. Franke; K. Frantzen; T. Fuchs; T. K. Gaisser; J. Gallagher; L. Gerhardt; L. Gladstone; T. Glüsenkamp; A. Goldschmidt; G. Golup; J. A. Goodman; D. Góra; D. Grant; A. Groß; M. Gurtner; C. Ha; A. Haj Ismail; A. Hallgren; F. Halzen; K. Hanson; D. Heereman; P. Heimann; D. Heinen; K. Helbing; R. Hellauer; S. Hickford; G. C. Hill; K. D. Hoffman; R. Hoffmann; A. Homeier; K. Hoshina; W. Huelsnitz; P. O. Hulth; K. Hultqvist; S. Hussain; A. Ishihara; E. Jacobi; J. Jacobsen; G. S. Japaridze; K. Jero; O. Jlelati; B. Kaminsky; A. Kappes; T. Karg; A. Karle; J. L. Kelley; J. Kiryluk; F. Kislat; J. Kläs; S. R. Klein; J. -H. Köhne; G. Kohnen; H. Kolanoski; L. Köpke; C. Kopper; S. Kopper; D. J. Koskinen; M. Kowalski; M. Krasberg; G. Kroll; J. Kunnen; N. Kurahashi; T. Kuwabara; M. Labare; H. Landsman; M. J. Larson; M. Lesiak-Bzdak; J. Leute; J. Lünemann; J. Madsen; R. Maruyama; K. Mase; H. S. Matis; F. McNally; K. Meagher; M. Merck; P. Mészáros; T. Meures; S. Miarecki; E. Middell; N. Milke; J. Miller; L. Mohrmann; T. Montaruli; R. Morse; R. Nahnhauer; U. Naumann; H. Niederhausen; S. C. Nowicki; D. R. Nygren; A. Obertacke; S. Odrowski; A. Olivas; M. Olivo; A. O'Murchadha; L. Paul; J. A. Pepper; C. Pérez de los Heros; C. Pfendner; D. Pieloth; N. Pirk; J. Posselt; P. B. Price; G. T. Przybylski; L. Rädel; K. Rawlins; P. Redl; E. Resconi; W. Rhode; M. Ribordy; M. Richman; B. Riedel; J. P. Rodrigues; C. Rott; T. Ruhe; B. Ruzybayev; D. Ryckbosch; S. M. Saba; T. Salameh; H. -G. Sander; M. Santander; S. Sarkar; K. Schatto; M. Scheel; F. Scheriau; T. Schmidt; M. Schmitz; S. Schoenen; S. Schöneberg; L. Schönherr; A. Schönwald; A. Schukraft; L. Schulte; O. Schulz; D. Seckel; S. H. Seo; Y. Sestayo; S. Seunarine; C. Sheremata; M. W. E. Smith; M. Soiron; D. Soldin; G. M. Spiczak; C. Spiering; M. Stamatikos; T. Stanev; A. Stasik; T. Stezelberger; R. G. Stokstad; A. Stößl; E. A. Strahler; R. Ström; G. W. Sullivan; H. Taavola; I. Taboada; A. Tamburro; S. Ter-Antonyan; S. Tilav; P. A. Toale; S. Toscano; M. Usner; D. van der Drift; N. van Eijndhoven; A. Van Overloop; J. van Santen; M. Vehring; M. Voge; M. Vraeghe; C. Walck; T. Waldenmaier; M. Wallraff; R. Wasserman; Ch. Weaver; M. Wellons; C. Wendt; S. Westerhoff; N. Whitehorn; K. Wiebe; C. H. Wiebusch; D. R. Williams; H. Wissing; M. Wolf; T. R. Wood; C. Xu; D. L. Xu; X. W. Xu; J. P. Yanez; G. Yodh; S. Yoshida; P. Zarzhitsky; J. Ziemann; S. Zierke; A. Zilles; M. Zoll

    2013-01-22T23:59:59.000Z

    The IceCube Neutrino Observatory, approximately 1 km^3 in size, is now complete with 86 strings deployed in the Antarctic ice. IceCube detects the Cherenkov radiation emitted by charged particles passing through or created in the ice. To realize the full potential of the detector, the properties of light propagation in the ice in and around the detector must be well understood. This report presents a new method of fitting the model of light propagation in the ice to a data set of in-situ light source events collected with IceCube. The resulting set of derived parameters, namely the measured values of scattering and absorption coefficients vs. depth, is presented and a comparison of IceCube data with simulations based on the new model is shown.

  14. Ice Shelf Water plume flow beneath Filchner-Ronne Ice Shelf, Antarctica

    E-Print Network [OSTI]

    Feltham, Daniel

    the thinning of Pine Island Glacier in West Antarctica and the collapse of parts of the Larsen Ice Shelf temperature variation is called the ``ice pump'' [Lewis and Perkin, 1983; Jenkins and Bombosch, 1995]. [5

  15. Controlling ice nucleation through surface hydrophilicity

    E-Print Network [OSTI]

    Stephen J. Cox; Shawn M. Kathmann; Ben Slater; Angelos Michaelides

    2015-01-08T23:59:59.000Z

    Ice formation is one of the most common and important processes on Earth and almost always occurs at the surface of a material. A basic understanding of how the physiochemical properties of a material's surface affects its ability to form ice has remained elusive. Here we use molecular dynamics simulations to directly probe heterogeneous ice nucleation at an hexagonal surface of a nanoparticle of varying hydrophilicity. Surprisingly, we find that structurally identical surfaces can both inhibit and promote ice formation and analogous to a chemical catalyst, it is found that an optimal interaction between the surface and the water exists for promoting ice nucleation. We use our microscopic understanding of the mechanism to design a modified surface in silico with enhanced ice nucleating ability.

  16. Observations of ice thickness and frazil ice in the St. Lawrence Island polynya from satellite imagery, upward looking sonar, and

    E-Print Network [OSTI]

    Washington at Seattle, University of

    . The combination of the SAR imagery and ULS observations also allow measurement of the pack ice advection velocityObservations of ice thickness and frazil ice in the St. Lawrence Island polynya from satellite define a thermal ice thickness from the AVHRR retrieval of ice surface temperature combined

  17. INDICATOR: LAKE ERIE ICE COVER Winter ice cover on Lake Erie affects the amount of heat and moisture transferred

    E-Print Network [OSTI]

    102 INDICATOR: LAKE ERIE ICE COVER Background Winter ice cover on Lake Erie affects the amount of heat and moisture transferred between the lake and the atmosphere. During winter, ice and snow can decrease the amount of light available below the ice surface for photosynthesis. In the absence of an ice

  18. 4, 107128, 2007 Sea-ice-drift

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    OSD 4, 107­128, 2007 Sea-ice-drift dynamics and pack fracture A. Chmel et al. Title Page Abstract aspects of the sea-ice-drift dynamics and pack fracture A. Chmel 1 , V. N. Smirnov 2 , and L. V. Panov 2 1 to: A. Chmel (chmel@mail.ioffe.ru) 107 #12;OSD 4, 107­128, 2007 Sea-ice-drift dynamics and pack

  19. Summer ICE@Tech Computing Camps

    E-Print Network [OSTI]

    Guzdial, Mark

    Summer ICE@Tech Computing Camps Session I: June 5th - June 9th Session II: July 10th ­ July 14th (404) 385-2273 Fax (404) 385-0965 http://www.cc.gatech.edu/campice 1 #12;2 Summer ICE@Tech Program Handbook #12;3 Summer ICE@Tech is a computing and technology program for students entering 10th , 11th

  20. Mixed crystal organic scintillators

    DOE Patents [OSTI]

    Zaitseva, Natalia P; Carman, M Leslie; Glenn, Andrew M; Hamel, Sebastien; Hatarik, Robert; Payne, Stephen A; Stoeffl, Wolfgang

    2014-09-16T23:59:59.000Z

    A mixed organic crystal according to one embodiment includes a single mixed crystal having two compounds with different bandgap energies, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source, wherein the signal response signature does not include a significantly-delayed luminescence characteristic of neutrons interacting with the organic crystal relative to a luminescence characteristic of gamma rays interacting with the organic crystal. According to one embodiment, an organic crystal includes bibenzyl and stilbene or a stilbene derivative, the organic crystal having a physical property of exhibiting a signal response signature for neutrons from a radioactive source.

  1. Simulating mixed-phase Arctic stratus clouds: Sensitivity to ice initiationmechanisms

    SciTech Connect (OSTI)

    Sednev, I.; Menon, S.; McFarquhar, G.

    2009-04-10T23:59:59.000Z

    The importance of Arctic mixed-phase clouds on radiation and the Arctic climate is well known. However, the development of mixed-phase cloud parameterization for use in large scale models is limited by lack of both related observations and numerical studies using multidimensional models with advanced microphysics that provide the basis for understanding the relative importance of different microphysical processes that take place in mixed-phase clouds. To improve the representation of mixed-phase cloud processes in the GISS GCM we use the GISS single-column model coupled to a bin resolved microphysics (BRM) scheme that was specially designed to simulate mixed-phase clouds and aerosol-cloud interactions. Using this model with the microphysical measurements obtained from the DOE ARM Mixed-Phase Arctic Cloud Experiment (MPACE) campaign in October 2004 at the North Slope of Alaska, we investigate the effect of ice initiation processes and Bergeron-Findeisen process (BFP) on glaciation time and longevity of single-layer stratiform mixed-phase clouds. We focus on observations taken during October 9th-10th, which indicated the presence of a single-layer mixed-phase clouds. We performed several sets of 12-hour simulations to examine model sensitivity to different ice initiation mechanisms and evaluate model output (hydrometeors concentrations, contents, effective radii, precipitation fluxes, and radar reflectivity) against measurements from the MPACE Intensive Observing Period. Overall, the model qualitatively simulates ice crystal concentration and hydrometeors content, but it fails to predict quantitatively the effective radii of ice particles and their vertical profiles. In particular, the ice effective radii are overestimated by at least 50%. However, using the same definition as used for observations, the effective radii simulated and that observed were more comparable. We find that for the single-layer stratiform mixed-phase clouds simulated, process of ice phase initiation due to freezing of supercooled water in both saturated and subsaturated (w.r.t. water) environments is as important as primary ice crystal origination from water vapor. We also find that the BFP is a process mainly responsible for the rates of glaciation of simulated clouds. These glaciation rates cannot be adequately represented by a water-ice saturation adjustment scheme that only depends on temperature and liquid and solid hydrometeors contents as is widely used in bulk microphysics schemes and are better represented by processes that also account for supersaturation changes as the hydrometeors grow.

  2. Simulating mixed-phase Arctic stratus clouds: sensitivity to ice initiation mechanisms

    SciTech Connect (OSTI)

    Sednev, Igor; Sednev, I.; Menon, S.; McFarquhar, G.

    2008-02-18T23:59:59.000Z

    The importance of Arctic mixed-phase clouds on radiation and the Arctic climate is well known. However, the development of mixed-phase cloud parameterization for use in large scale models is limited by lack of both related observations and numerical studies using multidimensional models with advanced microphysics that provide the basis for understanding the relative importance of different microphysical processes that take place in mixed-phase clouds. To improve the representation of mixed-phase cloud processes in the GISS GCM we use the GISS single-column model coupled to a bin resolved microphysics (BRM) scheme that was specially designed to simulate mixed-phase clouds and aerosol-cloud interactions. Using this model with the microphysical measurements obtained from the DOE ARM Mixed-Phase Arctic Cloud Experiment (MPACE) campaign in October 2004 at the North Slope of Alaska, we investigate the effect of ice initiation processes and Bergeron-Findeisen process (BFP) on glaciation time and longevity of single-layer stratiform mixed-phase clouds. We focus on observations taken during 9th-10th October, which indicated the presence of a single-layer mixed-phase clouds. We performed several sets of 12-h simulations to examine model sensitivity to different ice initiation mechanisms and evaluate model output (hydrometeors concentrations, contents, effective radii, precipitation fluxes, and radar reflectivity) against measurements from the MPACE Intensive Observing Period. Overall, the model qualitatively simulates ice crystal concentration and hydrometeors content, but it fails to predict quantitatively the effective radii of ice particles and their vertical profiles. In particular, the ice effective radii are overestimated by at least 50%. However, using the same definition as used for observations, the effective radii simulated and that observed were more comparable. We find that for the single-layer stratiform mixed-phase clouds simulated, process of ice phase initiation due to freezing of supercooled water in both saturated and undersaturated (w.r.t. water) environments is as important as primary ice crystal origination from water vapor. We also find that the BFP is a process mainly responsible for the rates of glaciation of simulated clouds. These glaciation rates cannot be adequately represented by a water-ice saturation adjustment scheme that only depends on temperature and liquid and solid hydrometeors contents as is widely used in bulk microphysics schemes and are better represented by processes that also account for supersaturation changes as the hydrometeors grow.

  3. H2 ICE Combustion | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    H2 ICE Combustion Share Description Hydrogen combustion inside a direct injection H2 engine Topic Energy Energy efficiency Vehicles Hydrogen & fuel cells Credit S. Ciatti This...

  4. Viscosity of interfacial water regulates ice nucleation

    SciTech Connect (OSTI)

    Li, Kaiyong; Chen, Jing; Zhang, Qiaolan; Zhang, Yifan [Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China) [Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Xu, Shun; Zhou, Xin [School of Physics, University of Chinese Academy of Sciences, Beijing 100049 (China)] [School of Physics, University of Chinese Academy of Sciences, Beijing 100049 (China); Cui, Dapeng; Wang, Jianjun, E-mail: wangj220@iccas.ac.cn; Song, Yanlin [Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)] [Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-03-10T23:59:59.000Z

    Ice formation on solid surfaces is an important phenomenon in many fields, such as cloud formation and atmospheric icing, and a key factor for applications in preventing freezing. Here, we report temperature-dependent nucleation rates of ice for hydrophilic and hydrophobic surfaces. The results show that hydrophilic surface presents a lower ice nucleation rate. We develop a strategy to extract the thermodynamic parameters, J{sub 0} and ?, in the context of classical nucleation theory. From the extracted J{sub 0} and ?, we reveal the dominant role played by interfacial water. The results provide an insight into freezing mechanism on solid surfaces.

  5. Dynamics of colloidal particles in ice

    E-Print Network [OSTI]

    Melissa Spannuth; S. G. J. Mochrie; S. S. L. Peppin; J. S. Wettlaufer

    2010-12-31T23:59:59.000Z

    We use X-ray Photon Correlation Spectroscopy (XPCS) to probe the dynamics of colloidal particles in polycrystalline ice. During freezing, the dendritic ice morphology and rejection of particles from the ice created regions of high-particle-density, where some of the colloids were forced into contact and formed disordered aggregates. We find that the particles in these high density regions underwent ballistic motion coupled with both stretched and compressed exponential decays of the intensity autocorrelation function, and that the particles' characteristic velocity increased with temperature. We explain this behavior in terms of ice grain boundary migration.

  6. BISICLES Captures Details of Retreating Antarctic Ice

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Retreating Antarctic Ice March 30, 2013 | Tags: Climate Research, Hopper, Math & Computer Science Contact: Linda Vu, lvu@lbl.gov, +1 510 495 2402 Berkeley Lab Contributes...

  7. Past Accumulation Rates of the Western Antarctic Ice Sheet Near an Ice Divide 

    E-Print Network [OSTI]

    Child, Sarah

    2009-08-12T23:59:59.000Z

    The study of accumulation rates of ice is a direct link to the evolution of ice sheet. It is believed by scientists that ice sheet evolution will aid in the mystery of climate change and may lead to predictions about climates in the future...

  8. Satellite SAR Remote Sensing of Great Lakes Ice Cover, Part 2. Ice Classification and Mapping

    E-Print Network [OSTI]

    Satellite SAR Remote Sensing of Great Lakes Ice Cover, Part 2. Ice Classification and Mapping° to 60° for all polarizations, was processed to radar cross-section to establish a library of signatures (look-up table) for different ice types. The library is used in the computer classifica- tion

  9. white paper, 9 March 2009 An ice core to reconstruct Greenland ice sheet mass balance

    E-Print Network [OSTI]

    Box, Jason E.

    white paper, 9 March 2009 1 An ice core to reconstruct Greenland a handful of years suggest a profound Greenland ice sheet mass balance sensitivity (2000) found that the Greenland ice sheet lost as much as 2/3 its current

  10. Pressure cryocooling protein crystals

    DOE Patents [OSTI]

    Kim, Chae Un (Ithaca, NY); Gruner, Sol M. (Ithaca, NY)

    2011-10-04T23:59:59.000Z

    Preparation of cryocooled protein crystal is provided by use of helium pressurizing and cryocooling to obtain cryocooled protein crystal allowing collection of high resolution data and by heavier noble gas (krypton or xenon) binding followed by helium pressurizing and cryocooling to obtain cryocooled protein crystal for collection of high resolution data and SAD phasing simultaneously. The helium pressurizing is carried out on crystal coated to prevent dehydration or on crystal grown in aqueous solution in a capillary.

  11. ARKTOS: An intelligent system for SAR sea ice image classification

    E-Print Network [OSTI]

    Soh, L. K.; Tsatsoulis, Costas; Gineris, D.; Bertoia, C.

    2004-01-01T23:59:59.000Z

    We present an intelligent system for satellite sea ice image analysis named Advanced Reasoning using Knowledge for T ping Of Sea ice (ARKTOS). ARKTOS performs fully automated analysis of synthetic aperture radar (SAR) sea ice images by mimicking...

  12. Hail Ice Damage of Stringer-Stiffened Curved Composite Panels /

    E-Print Network [OSTI]

    Le, Jacqueline Linh

    2013-01-01T23:59:59.000Z

    Damage. Composite Structures 2003;62:213–21. Ice Drop.How to make clear ice. 28 February 2011. Victoria, BC,2011/02/how-to- make-clear-ice-that-actually-works/ Graham,

  13. Dust takes detour on ice-cloud journey | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dust takes detour on ice-cloud journey Dust takes detour on ice-cloud journey Pollution-coated particles bypass ice formation, but influence clouds Cirrus clouds are composed of...

  14. Sandia National Laboratories: Ice-Sheet Simulation Code Matures...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Research & Capabilities Ice-flow velocity magnitude myr on the surface of the Greenland Ice Sheet, as computed by the AlbanyFELIX finite element code. Ice-flow velocity...

  15. Laboratory H2O:CO2 ice desorption data: entrapment dependencies and its parameterization with an extended three-phase model

    E-Print Network [OSTI]

    Fayolle, Edith C; Cuppen, Herma M; Visser, Ruud; Linnartz, Harold; 10.1051/0004-6361/201016121

    2011-01-01T23:59:59.000Z

    Ice desorption affects the evolution of the gas-phase chemistry during the protostellar stage, and also determines the chemical composition of comets forming in circumstellar disks. From observations, most volatile species are found in H2O-dominated ices. The aim of this study is first to experimentally determine how entrapment of volatiles in H2O ice depends on ice thickness, mixture ratio and heating rate, and second, to introduce an extended three-phase model (gas, ice surface and ice mantle) to describe ice mixture desorption with a minimum number of free parameters. Thermal H2O:CO2 ice desorption is investigated in temperature programmed desorption experiments of thin (10 - 40 ML) ice mixtures under ultra-high vacuum conditions. Desorption is simultaneously monitored by mass spectrometry and reflection-absorption infrared spectroscopy. The H2O:CO2 experiments are complemented with selected H2O:CO, and H2O:CO2:CO experiments. The results are modeled with rate equations that connect the gas, ice surface an...

  16. The Patty Ice Arena User Responsibilities and Conduct is designed to create better communication between the patrons of the Patty Ice Arena and the Facilities Services' Patty Ice

    E-Print Network [OSTI]

    Wagner, Diane

    PURPOSE: The Patty Ice Arena User Responsibilities and Conduct is designed to create better communication between the patrons of the Patty Ice Arena and the Facilities Services' Patty Ice Arena management or other misuse of any part of the Patty Ice Arena may result in an individual, team, or organization being

  17. Heterogeneous Nucleation of Ice on Anthropogenic Organic Particles...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nucleation of Ice on Anthropogenic Organic Particles Collected in Mexico City. Heterogeneous Nucleation of Ice on Anthropogenic Organic Particles Collected in Mexico City....

  18. Heterogeneous ice nucleation and water uptake by field-collected...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ice nucleation and water uptake by field-collected atmospheric particles below 273 K. Heterogeneous ice nucleation and water uptake by field-collected atmospheric particles below...

  19. Crystalline Ice Growth on Pt(111): Observation of a Hydrophobic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Crystalline Ice Growth on Pt(111): Observation of a Hydrophobic Water Monolayer. Crystalline Ice Growth on Pt(111): Observation of a Hydrophobic Water Monolayer. Abstract: The...

  20. The dependence of ice microphysics on aerosol concentration in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The dependence of ice microphysics on aerosol concentration in arctic mixed-phase stratus clouds during ISDAC and M-PACE. The dependence of ice microphysics on aerosol...

  1. Complex systems influence melting of Greenland ice sheet

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Complex systems influence melting of Greenland ice sheet Complex systems influence melting of Greenland ice sheet International research team's field work shows that, well, things...

  2. Cold neutron scattering in imperfect deuterium crystals

    E-Print Network [OSTI]

    Andrzej Adamczak

    2010-12-10T23:59:59.000Z

    The differential cross sections for cold neutron scattering in mosaic deuterium crystals have been calculated for various target temperatures. The theoretical results are compared with the recent experimental data for the neutron wavelengths $\\lambda\\approx$~1--9~\\AA. It is shown that the structures of observed Bragg peaks can be explained by the mosaic spread of about $3^{\\circ}$ and contributions from a~limited number of crystal orientations. Such a~crystal structure should be also taken into account in ultracold neutron upscattering due to the coherent phonon annihilation in solid deuterium.

  3. Unlocking a Sea Ice Secret

    SciTech Connect (OSTI)

    Dr. Rachel Obbard

    2013-04-22T23:59:59.000Z

    Dr. Rachel Obbard and her research group from Dartmouth College traveled to the Antarctic to collect samples of sea ice. Next stop: the GeoSoilEnviroCARS x-ray beamline at the Advanced Photon Source at Argonne National Laboratory in Illinois. This U.S. Department of Energy Office of Science synchrotron x-ray research facility gave the Obbard team the frontier scientific tools they needed to study the path bromide takes as it travels from the ocean to the atmosphere.

  4. ARM - Measurement - Cloud ice particle

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow,ice particle ARM Data Discovery Browse Data

  5. ARM - Measurement - Ice water content

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow,ice particleSize Distributiontypes

  6. ARM - Measurement - Ice water path

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow,ice particleSize Distributiontypespath ARM

  7. ARM - TWP-ICE Maps

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP :ProductsVaisalaAlaskaInstruments NSASteeringContactsTWP-ICE Maps

  8. Ice Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdfGetecGtel JumpCounty, Texas:ITC Transmission Jump to: navigation,IbervilleIce

  9. Testing the physics of heat conduction in glasses and crystals using high pressure

    E-Print Network [OSTI]

    Braun, Paul

    Chen California Institute of Technology Jackie Li University of Michigan supported by CDAC and AFOSR, Wen-Pin Hsieh, Mark Losego, Paul Braun, Dallas Trinkle University of Illinois at Urbana Champaign Bin for disordered materials ­ Leibfried-Schlömann equation for perfect crystals PMMA polymer water ice VII #12;Time

  10. Passive ice freezing-releasing heat pipe

    DOE Patents [OSTI]

    Gorski, Anthony J. (Lemont, IL); Schertz, William W. (Batavia, IL)

    1982-01-01T23:59:59.000Z

    A heat pipe device has been developed which permits completely passive ice formation and periodic release of ice without requiring the ambient temperature to rise above the melting point of water. This passive design enables the maximum amount of cooling capacity to be stored in the tank.

  11. IceCube Project Monthly Report Accomplishments

    E-Print Network [OSTI]

    Saffman, Mark

    ;3 The latest revised estimates were modified to reflect the anticipated changes resulting from the Raytheon in Raytheon Polar Services completing the IceCube Laboratory. $1 million is from the lagging receipts. The on-ice Integrated Master Schedule is underway and being worked on this week with Raytheon Polar

  12. CRYSTALLIZATION IN MULTICOMPONENT GLASSES

    SciTech Connect (OSTI)

    KRUGER AA; HRMA PR

    2009-10-08T23:59:59.000Z

    In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.

  13. Theory of ice-skating

    E-Print Network [OSTI]

    Berre, Martine Le

    2015-01-01T23:59:59.000Z

    Almost frictionless skating on ice relies on a thin layer of melted water insulating mechanically the blade of the skate from ice. Using the basic equations of fluid mechanics and Stefan law, we derive a set of two coupled equations for the thickness of the film and the length of contact, a length scale which cannot be taken as its value at rest. The analytical study of these equations allows to define a small a-dimensional parameter depending on the longitudinal coordinate which can be neglected everywhere except close to the contact points at the front and the end of the blade, where a boundary layer solution is given. This solution provides without any calculation the order of magnitude of the film thickness, and its dependence with respect to external parameters like the velocity and mass of the skater and the radius of profile and bite angle of the blade, in good agreement with the numerical study. Moreover this solution also shows that a lubricating water layer of macroscopic thickness always exists for...

  14. Magnetic Monopoles in Spin Ice

    E-Print Network [OSTI]

    Claudio Castelnovo; Roderich Moessner; Shivaji L. Sondhi

    2007-10-31T23:59:59.000Z

    Electrically charged particles, such as the electron, are ubiquitous. By contrast, no elementary particles with a net magnetic charge have ever been observed, despite intensive and prolonged searches. We pursue an alternative strategy, namely that of realising them not as elementary but rather as emergent particles, i.e., as manifestations of the correlations present in a strongly interacting many-body system. The most prominent examples of emergent quasiparticles are the ones with fractional electric charge e/3 in quantum Hall physics. Here we show that magnetic monopoles do emerge in a class of exotic magnets known collectively as spin ice: the dipole moment of the underlying electronic degrees of freedom fractionalises into monopoles. This enables us to account for a mysterious phase transition observed experimentally in spin ice in a magnetic field, which is a liquid-gas transition of the magnetic monopoles. These monopoles can also be detected by other means, e.g., in an experiment modelled after the celebrated Stanford magnetic monopole search.

  15. Change Number

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccessAlamos LaboratoryCertified Reference6-02-01Change Number

  16. Flight tests of a digital data acquisition system for analysis of ultrasonic pulse-echo signals used to measure ice accretion

    E-Print Network [OSTI]

    Ryan, Justin Mark

    1986-01-01T23:59:59.000Z

    A number of signal processing algorithms were developed for analyzing ultrasonic signals used to measure aircraft ice accretion in flight. A high speed digital signal acquisition system was designed and constructed to ...

  17. THE THERMAL EVOLUTION OF ICES IN THE ENVIRONMENTS OF NEWLY FORMED STARS: THE CO{sub 2} DIAGNOSTIC

    SciTech Connect (OSTI)

    Cook, A. M.; Whittet, D. C. B. [New York Center for Astrobiology and Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180 (United States); Shenoy, S. S. [Spitzer Science Center, Mail Code 220-6, California Institute of Technology, Pasadena, CA 91125 (United States); Gerakines, P. A.; White, D. W. [Department of Physics, University of Alabama at Birmingham, 310 Campbell Hall, 1300 University Boulevard, Birmingham, AL 35294 (United States); Chiar, J. E. [SETI Institute, 189 Bernardo Avenue, Mountain View, CA 94043 (United States)

    2011-04-01T23:59:59.000Z

    Archival data from the Infrared Spectrometer of the Spitzer Space Telescope are used to study the 15 {mu}m absorption feature of solid CO{sub 2} toward 28 young stellar objects (YSOs) of approximately solar mass. Fits to the absorption profile using laboratory spectra enable categorization according to the degree of thermal processing of the ice matrix that contains the CO{sub 2}. The majority of YSOs in our sample (20 out of 28) are found to be consistent with a combination of polar (H{sub 2}O-rich) and nonpolar (CO-rich) ices at low temperature; the remainder exhibit profile structure consistent with partial crystallization as the result of significant heating. Ice-phase column densities of CO{sub 2} are determined and compared with those of other species. Lines of sight with crystallization signatures in their spectra are found to be systematically deficient in solid-phase CO, as expected if CO is being sublimated in regions where the ices are heated to crystallization temperatures. Significant variation is found in the CO{sub 2} abundance with respect to both H{sub 2}O (the dominant ice constituent) and total dust column (quantified by the extinction, A{sub V}). YSOs in our sample display typically higher CO{sub 2} concentrations (independent of evidence for thermal processing) in comparison to quiescent regions of the prototypical cold molecular cloud. This suggests that enhanced CO{sub 2} production is driven by photochemical reactions in proximity to some YSOs, and that photoprocessing and thermal processing may occur independently.

  18. First data from DM-Ice17

    E-Print Network [OSTI]

    DM-Ice Collaboration; :; J. Cherwinka; D. Grant; F. Halzen; K. M. Heeger; L. Hsu; A. J. F. Hubbard; A. Karle; M. Kauer; V. A. Kudryavtsev; C. Macdonald; R. H. Maruyama; S. Paling; W. Pettus; Z. P. Pierpoint; B. N. Reilly; M. Robinson; P. Sandstrom; N. J. C. Spooner; S. Telfer; L. Yang

    2014-11-13T23:59:59.000Z

    We report the first analysis of background data from DM-Ice17, a direct-detection dark matter experiment consisting of 17 kg of NaI(Tl) target material. It was codeployed with IceCube 2457 m deep in the South Pole glacial ice in December 2010 and is the first such detector operating in the Southern Hemisphere. The background rate in the 6.5 - 8.0 keVee region is measured to be 7.9 +/- 0.4 counts/day/keV/kg. This is consistent with the expected background from the detector assemblies with negligible contributions from the surrounding ice. The successful deployment and operation of DM-Ice17 establishes the South Pole ice as a viable location for future underground, low-background experiments in the Southern Hemisphere. The detector assembly and deployment are described here, as well as the analysis of the DM-Ice17 backgrounds based on data from the first two years of operation after commissioning, July 2011 - June 2013.

  19. Modelling Sea Ice Growth Mark J. McGuinness

    E-Print Network [OSTI]

    McGuinness, Mark

    salinity. The saltier the brine, the lower the freezing point. When salinity is above the critical value is rejected by growing ice as a dense brine, but the brine cannot escape as rapidly as heat at the ice, trapping brine in the ice-brine mixture. This constitutional supercooling causes the ice-ocean interface

  20. Introduction Microorganisms in sea ice function ecologically in the

    E-Print Network [OSTI]

    Stewart, Frank

    of the pack via brine drainage, ice melting, or ice break-up (Garrison & Buck 1989 and references thereinIntroduction Microorganisms in sea ice function ecologically in the Antarctic marine ecosystem where pelagic and sea ice habitats are intrinsically coupled (Laws 1985, Garrison 1991, Eicken 1992

  1. FIRST PRINCIPLES MODELING FOR LIDAR SENSING OF COMPLEX ICE SURFACES

    E-Print Network [OSTI]

    Kerekes, John

    FIRST PRINCIPLES MODELING FOR LIDAR SENSING OF COMPLEX ICE SURFACES J. Kerekes, A. Goodenough, S of monitoring the dynamics and mass balance of glaciers, ice caps, and ice sheets. However, it is also known that ice surfaces can have complex 3-dimensional structure, which can challenge their accurate retrieval

  2. Microstructure through an ice sheet Tobias Binder1, a

    E-Print Network [OSTI]

    Garbe, Christoph S.

    Microstructure through an ice sheet Tobias Binder1, a , Ilka Weikusat2, b , Johannes Freitag2, c.Garbe@iwr.uni-heidelberg.de, e Dietmar.Wagenbach@iup.uni-heidelberg.de, f Sepp.Kipfstuhl@awi.de Keywords: Ice, microstructure characterization, grain boundary curvature, image processing Abstract. Ice cores through an ice sheet can

  3. ORIGINAL ARTICLE Diatom assemblages promote ice formation in large

    E-Print Network [OSTI]

    Lee Jr., Richard E.

    ORIGINAL ARTICLE Diatom assemblages promote ice formation in large lakes NA D'souza1,3 , Y evidence for the directed formation of ice by planktonic communities dominated by filamentous diatoms sampled from the ice-covered Laurentian Great Lakes. We hypothesize that ice formation promotes attachment

  4. Age characteristics in a multidecadal Arctic sea ice simulation

    SciTech Connect (OSTI)

    Hunke, Elizabeth C [Los Alamos National Laboratory; Bitz, Cecllia M [UNIV. OF WASHINGTON

    2008-01-01T23:59:59.000Z

    Results from adding a tracer for age of sea ice to a sophisticated sea ice model that is widely used for climate studies are presented. The consistent simulation of ice age, dynamics, and thermodynamics in the model shows explicitly that the loss of Arctic perennial ice has accelerated in the past three decades, as has been seen in satellite-derived observations. Our model shows that the September ice age average across the Northern Hemisphere varies from about 5 to 8 years, and the ice is much younger (about 2--3 years) in late winter because of the expansion of first-year ice. We find seasonal ice on average comprises about 5% of the total ice area in September, but as much as 1.34 x 10{sup 6} km{sup 2} survives in some years. Our simulated ice age in the late 1980s and early 1990s declined markedly in agreement with other studies. After this period of decline, the ice age began to recover, but in the final years of the simulation very little young ice remains after the melt season, a strong indication that the age of the pack will again decline in the future as older ice classes fail to be replenished. The Arctic ice pack has fluctuated between older and younger ice types over the past 30 years, while ice area, thickness, and volume all declined over the same period, with an apparent acceleration in the last decade.

  5. Dynamics of Ice Nucleation on Water Repellent Surfaces Azar Alizadeh,*,

    E-Print Network [OSTI]

    Dhinojwala, Ali

    for nonicing applications. 1. INTRODUCTION Ice accretion on surfaces of aircraft, wind turbine blades, oil

  6. Self-excited oscillations in sea ice and evaluation of the ice forces

    SciTech Connect (OSTI)

    Smirnov, V.N. [Arctic and Antarctic Research Inst., St. Petersburg (Russian Federation)

    1996-12-01T23:59:59.000Z

    The processes of the dynamical interactions of the ice are described. Special attention is given to the self-excited oscillating processes when the ice goes through periodical deformations similar to these which appear in the structures in the sea ice. The range of the self-excited oscillations periods is from 0.1 s to 20 s. The jump-like processes transform themselves into the quasi-harmonical ones up to sound frequency range. For comparison purposes the spectra of the frictional self-excited oscillations in the glaciers are presented. An iceberg interacting with the drifting ice also forms self-excited oscillating system with period of up to 10 s. An example of numerical evaluation of the forces of interaction between a drifting ice island and the sea ice is given.

  7. RGPS/Model Ice Deformation July 3, 2003 1 Sea Ice Deformation Rates From Satellite Measurements and in a Model

    E-Print Network [OSTI]

    Lindsay, Ron

    of the Arctic geophysical environment. The deformation rate of pack ice, determined from the spatial gradientsRGPS/Model Ice Deformation July 3, 2003 1 Sea Ice Deformation Rates From Satellite Measurements The deformation of sea ice is an important element of the Arctic climate system because of its influence

  8. Communication: On the stability of ice 0, ice i, and I h D. Quigley, D. Alf, and B. Slater

    E-Print Network [OSTI]

    Alfè, Dario

    Communication: On the stability of ice 0, ice i, and I h D. Quigley, D. Alfè, and B. Slater (2014) Communication: On the stability of ice 0, ice i, and Ih D. Quigley,1,a) D. Alfè,2 and B. Slater3

  9. ice-surface lowering or some regional climate change induced by ice-surface lowering. If attributed solely to a

    E-Print Network [OSTI]

    Flint-Garcia, Sherry

    ice-surface lowering or some regional climate change induced by ice-surface lowering. If attributed solely to a change in ice-surface elevation, the 3° to 4°C warming at Siple Dome (16) would indicate 500 to 650 m of ice-surface lowering, assuming a free atmospheric lapse rate of 6°C per 1000 m

  10. Inter-annual sea-ice dynamics and micro-algal biomass in winter pack ice of Marguerite Bay, Antarctica

    E-Print Network [OSTI]

    Stewart, Frank

    in this region (Stammerjohn et al., 2003; Stammerjohn and Smith, 1996). Changes in mesoscale ice dynamics

  11. Neutron detection with single crystal organic scintillators

    SciTech Connect (OSTI)

    Zaitseva, N; Newby, J; Hamel, S; Carman, L; Faust, M; Lordi, V; Cherepy, N; Stoeffl, W; Payne, S

    2009-07-15T23:59:59.000Z

    Detection of high-energy neutrons in the presence of gamma radiation background utilizes pulse-shape discrimination (PSD) phenomena in organics studied previously only with limited number of materials, mostly liquid scintillators and single crystal stilbene. The current paper presents the results obtained with broader varieties of luminescent organic single crystals. The studies involve experimental tools of crystal growth and material characterization in combination with the advanced computer modeling, with the final goal of better understanding the relevance between the nature of the organic materials and their PSD properties. Special consideration is given to the factors that may diminish or even completely obscure the PSD properties in scintillating crystals. Among such factors are molecular and crystallographic structures that determine exchange coupling and exciton mobility in organic materials and the impurity effect discussed on the examples of trans-stilbene, bibenzyl, 9,10-diphenylanthracene and diphenylacetylene.

  12. Photonic crystal light source

    DOE Patents [OSTI]

    Fleming, James G. (Albuquerque, NM); Lin, Shawn-Yu (Albuquerque, NM); Bur, James A. (Corrales, NM)

    2004-07-27T23:59:59.000Z

    A light source is provided by a photonic crystal having an enhanced photonic density-of-states over a band of frequencies and wherein at least one of the dielectric materials of the photonic crystal has a complex dielectric constant, thereby producing enhanced light emission at the band of frequencies when the photonic crystal is heated. The dielectric material can be a metal, such as tungsten. The spectral properties of the light source can be easily tuned by modification of the photonic crystal structure and materials. The photonic crystal light source can be heated electrically or other heating means. The light source can further include additional photonic crystals that exhibit enhanced light emission at a different band of frequencies to provide for color mixing. The photonic crystal light source may have applications in optical telecommunications, information displays, energy conversion, sensors, and other optical applications.

  13. The Phases of Water Ice in the Solar Nebula

    E-Print Network [OSTI]

    Ciesla, Fred J

    2014-01-01T23:59:59.000Z

    Understanding the phases of water ice that were present in the solar nebula has implications for understanding cometary and planetary compositions as well as internal evolution of these bodies. Here we show that amorphous ice formed more readily than previously recognized, with formation at temperatures ice to form. This processing would be a natural consequence of ice dynamics, and would allow for the trapping of noble gases and other volatiles in water ice in the outer solar nebula.

  14. Crystal structure and interaction dependence of the crystal-melt interfacial free energy

    E-Print Network [OSTI]

    Davidchack, Ruslan L.; Laird, Brian Bostian

    2005-03-01T23:59:59.000Z

    we examine, via molecular simulation, the interfacial free energies for a large number of systems interacting with inverse-power potentials of varying range, crystal orientation, and crystal structure (fcc or bcc). By focusing on a general class... of model interaction potentials 0031-9007= understanding of the dependence of .0013 on is largely empirical. In 1950, Turnbull values of .0013 for a variety of materials, ob- from nucleation rate experiments. ed a strong correlation between the en- per...

  15. Observations of the Askaryan Effect in Ice

    SciTech Connect (OSTI)

    Gorham, P.W.

    2007-01-16T23:59:59.000Z

    We report on the first observations of the Askaryan effect in ice: coherent impulsive radio Cherenkov radiation from the charge asymmetry in an electromagnetic (EM) shower. Such radiation has been observed in silica sand and rock salt, but this is the first direct observation from an EM shower in ice. These measurements are important since the majority of experiments to date that rely on the effect for ultra-high energy neutrino detection are being performed using ice as the target medium. As part of the complete validation process for the Antarctic Impulsive Transient Antenna (ANITA) experiment, we performed an experiment at the Stanford Linear Accelerator Center (SLAC) in June 2006 using a 7.5 metric ton ice target, yielding results fully consistent with theoretical expectations.

  16. Neutrino Oscillation Measurements with IceCube

    E-Print Network [OSTI]

    Carsten Rott; for the IceCube Collaboration

    2008-10-20T23:59:59.000Z

    We present preliminary results for a neutrino oscillation analysis in progress on data collected with the IceCube 22-string detector during 2007 and 2008. The goal of this analysis is to measure muon neutrino disappearance as a function of energy for a constant baseline length of the diameter of the Earth by studying vertically up-going muon neutrinos. At this baseline disappearance effects are expected to become sizable at neutrino energies below 100 GeV. This energy range has not been previously explored with IceCube, however due to IceCube's vertical geometry there is some sensitivity for this specific class of events. Based on preliminary selection criteria, we show that IceCube has the potential to detect these events and we estimate the sensitivity to determining oscillation parameters.

  17. Observations of the Askaryan Effect in Ice

    E-Print Network [OSTI]

    ANITA collaboration; P. W. Gorham; S. W. Barwick; J. J. Beatty; D. Z. Besson; W. R. Binns; C. Chen; P. Chen; J. M. Clem; A. Connolly; P. F. Dowkontt; M. A. DuVernois; R. C. Field; D. Goldstein; A. Goodhue; C. Hast; C. L. Hebert; S. Hoover; M. H. Israel; J. Kowalski; J. G. Learned; K. M. Liewer; J. T. Link; E. Lusczek; S. Matsuno; B. Mercurio; C. Miki; P. Miocinovic; J. Nam; C. J. Naudet; J. Ng; R. Nichol; K. Palladino; K. Reil; A. Romero-Wolf; M. Rosen; D. Saltzberg; D. Seckel; G. S. Varner; D. Walz; F. Wu

    2007-01-12T23:59:59.000Z

    We report on the first observations of the Askaryan effect in ice: coherent impulsive radio Cherenkov radiation from the charge asymmetry in an electromagnetic (EM) shower. Such radiation has been observed in silica sand and rock salt, but this is the first direct observation from an EM shower in ice. These measurements are important since the majority of experiments to date that rely on the effect for ultra-high energy neutrino detection are being performed using ice as the target medium. As part of the complete validation process for the Antarctic Impulsive Transient Antenna (ANITA) experiment, we performed an experiment at the Stanford Linear Accelerator Center (SLAC) in June 2006 using a 7.5 metric ton ice target, yielding results fully consistent with theoretical expectations.

  18. Observations of the Askaryan Effect in Ice

    E-Print Network [OSTI]

    Barwick, S W; Besson, D Z; Binns, W R; Chen, P; Clem, J M; Connolly, A; Dowkontt, P F; Duvernois, M A; Field, R C; Goldstein, D; Goodhue, A; Gorham, P W; Hast, C; Hebert, C L; Hoover, S; Israel, M H; Kowalski, J; Learned, J G; Liewer, K M; Link, J T; Lusczek, E; Matsuno, S; Mercurio, B; Miki, C; Miocinovic, P; Nam, J; Naudet, C J; Ng, J; Nichol, R; Palladino, K J; Reil, K; Romero-Wolf, A; Rosen, M; Saltzberg, D; Secke, D; Varner, G S; Walz, D; Wu, F

    2006-01-01T23:59:59.000Z

    We report on the first observations of the Askaryan effect in ice: coherent impulsive radio Cherenkov radiation from the charge asymmetry in an electromagnetic (EM) shower. Such radiation has been observed in silica sand and rock salt, but this is the first direct observation from an EM shower in ice. These measurements are important since the majority of experiments to date that rely on the effect for ultra-high energy neutrino detection are being performed using ice as the target medium. As part of the complete validation process for the Antarctic Impulsive Transient Antenna (ANITA) experiment, we performed an experiment at the Stanford Linear Accelerator Center (SLAC) in June 2006 using a 7.5 metric ton ice target, yielding results fully consistent with theoretical expectations.

  19. Weakening of ice by magnesium perchlorate hydrate

    E-Print Network [OSTI]

    Lenferink, Hendrik J., 1985-

    2012-01-01T23:59:59.000Z

    I show that perchlorate hydrates, which have been indirectly detected at high Martian circumpolar latitudes by the Phoenix Mars Lander, have a dramatic effect upon the rheological behavior of polycrystalline water ice under ...

  20. Growth and characterization of diammonium copper disulphate hexahydrate single crystal

    SciTech Connect (OSTI)

    Siva Sankari, R. [Department of Physics, Agni College of Technology, Thalambur, Chennai 603103 (India); Perumal, Rajesh Narayana, E-mail: r.shankarisai@gmail.com [Department of Physics, SSN College of Engineering, Kalavakkam, Chennai 603110 (India)

    2014-03-01T23:59:59.000Z

    Graphical abstract: Diammonium copper disulphate hexahydrate (DACS) is one of the most promising inorganic dielectric crystals with exceptional mechanical properties. Good quality crystals of DACS were grown by using solution method in a period of 30 days. The grown crystals were subjected to single crystal X-ray diffraction analysis in order to establish their crystalline nature. Thermo gravimetric, differential thermal analysis, FTIR, and UV–vis–NIR analysis were performed for the crystal. Several solid state physical parameters have been determined for the grown crystals. The dielectric constant and the dielectric loss and AC conductivity of the grown crystal were studied as a function of frequency and temperature has been calculated and plotted. - Highlights: • Diammonium copper disulphate is grown for the first time and CCDC number obtained. • Thermal analysis is done to see the stability range of the crystals. • Band gap and UV cut off wavelength of the crystal are determined to be 2.4 eV and 472.86 nm, respectively. • Dielectric constant, dielectric loss and AC conductivity are plotted as a function of applied field. - Abstract: Diammonium copper disulphate hexahydrate is one of the most promising inorganic crystals with exceptional dielectric properties. A good quality crystal was harvested in a 30-day period using solution growth method. The grown crystal was subjected to various characterization techniques like single crystal X-ray diffraction analysis, thermo gravimetric, differential thermal analysis, FTIR, and UV–vis–NIR analysis. Unit cell dimensions of the grown crystal have been identified from XRD studies. Functional groups of the title compounds have been identified from FTIR studies. Thermal stability of the samples was checked by TG/DTA studies. Band gap of the crystal was calculated. The dielectric constant and dielectric loss were studied as a function of frequency of the applied field. AC conductivity was plotted as a function of temperature.

  1. Kinetics of growth of spinel crystals in a borosilicate glass

    SciTech Connect (OSTI)

    Alton, Jesse; Plaisted, Trevor J.; Hrma, Pavel R.

    2002-07-01T23:59:59.000Z

    Three aspects of the kinetics of spinel crystallization in a high-level waste (HLW) glass were studied: (1) the effect of nucleation agents on the number density (ns) of spinel crystals, (2) crystallization kinetics in a crushed glass, and (3) crystallization kinetics in a glass preheated at T > TL (liquidus temperature). In glass lacking in nucleation agents, ns was a strong function of temperature. In glasses with noble metals (Rh, Ru, Pd, and Pt), ns increased by up to four orders of magnitude and was nearly independent of temperature. The kinetics of spinel crystallization in crushed glass lacking nucleation agents was dominated by surface crystallization and was described by the Kolmogorov-Johnson-Mehl-Avrami (KJMA) equation with the Avrami exponent n {at} 0.5. For application to HLW glass melter processing, it was necessary to preheat glass at T > TL to eliminate the impact of temperature history and surface crystallization on crystal nucleation and growth. In the temperature range of glass processing, crystals descend under gravity when they reach a critical size. Below this critical size, crystallization kinetics is described by the KJMA equation and above the critical size by the Hixson-Crowell equation. At low temperatures, at which glass viscosity is high and diffusion is slow, the KJMA equation represents crystal growth from nucleation to equilibrium. As ns increases, the temperature interval of the transition from the KJMA to Hixson-Crowell regime shifts to a higher temperature.

  2. Kinetics of growth of spinel crystals in a borosilicate glass

    SciTech Connect (OSTI)

    Alton, Jesse; Plaisted, Trevor J.; Hrma, Pavel R.

    2002-08-08T23:59:59.000Z

    Three aspects of the kinetics of spinel crystallization in a high-level waste (HLW) glass were studied: (1) the effect of nucleation agents on the number density (ns) of spinel crystals, (2) crystallization kinetics in a crushed glass, and (3) crystallization kinetics in a glass preheated at T>TL (liquidus temperature). In glass lacking in nucleation agens, ns was a strong function of temperature. In glasses with noble metals (Rh, Ru, Pd, and Pt), ns increased by up to four orders of magnitude and was nearly independent of temperature. The kinetics of spinel crystallization in crushed glass lacking nucleation agents was dominated by surface crystallization and was described by the Kolmogorov-Johnson-Mehl-Avrami (KJMA) equation with the Avrami exponent n~0.5. For application to HLW glass melter processing, it was necessary to preheat glass at T>TL to eliminate the impact of temperature history and surface crystallization on crystal nucleation and growth. In the temperature range of glass processing, crystals descend under gravity when they reach a critical size. Below this critical size, crystallization kinetics is described by the KJMA equation and above the critical size by the Hixson-Crowell equation. At low temperatures, at which glass viscosity is high and diffusion is slow, the KJMA equation represents crystal growth from nucleation to equilibrium. As ns increases, the temperature interval of the transition from the KJMA to Hisxon-Crowell regime shifts to a higher temperature.

  3. Bedmap2: improved ice bed, surface and thickness datasets for Antarctica

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    Subglacial topography inferred from ice surface ter- rainSubglacial topography inferred from ice surface ter- rainsurface eleva- tion, ice thickness and subglacial topography

  4. Spread of ice mass loss into northwest Greenland observed by GRACE and GPS

    E-Print Network [OSTI]

    Khan, Shfaqat Abbas; Wahr, John; Bevis, Michael; Velicogna, Isabella; Kendrick, Eric

    2010-01-01T23:59:59.000Z

    oscillations and seasonal ice mass fluctuations, Eos Trans.2007), Rapid changes in ice discharge from Greenland outletW. et al. (2004), Greenland Ice Sheet: Increased coastal

  5. Regelation: why does ice melt under pressure?

    E-Print Network [OSTI]

    Chang Q Sun

    2015-01-28T23:59:59.000Z

    Unlike other unusual materials whose bonds contract under compression, the O:H nonbond undergoes contraction and the H-O bond elongation towards O:H and H-O length symmetry in water and ice. The energy drop of the H-O bond dictates the melting point Tm depression of ice. Once the pressure is relieved, the O:H-O bond fully recovers its initial state, resulting in Regelation.

  6. Regelation: why does ice melt under pressure?

    E-Print Network [OSTI]

    Sun, Chang Q

    2015-01-01T23:59:59.000Z

    Unlike other unusual materials whose bonds contract under compression, the O:H nonbond undergoes contraction and the H-O bond elongation towards O:H and H-O length symmetry in water and ice. The energy drop of the H-O bond dictates the melting point Tm depression of ice. Once the pressure is relieved, the O:H-O bond fully recovers its initial state, resulting in Regelation.

  7. Development of a Mobile Ice Nucleus Counter

    SciTech Connect (OSTI)

    Kok, Gregory; Kulkarni, Gourihar

    2014-07-10T23:59:59.000Z

    An ice nucleus counter has been constructed. The instrument uses built-in refrigeration systems for wall cooling. A cascade refrigeration system will allow the cold wall to operate as low as -70 deg C, and a single stage system can operate the warm wall at -45 deg C. A unique optical particle counter has been constructed using polarization detection of the scattered light. This allows differentiation of the particles exiting the chamber to determine if they are ice or liquid.

  8. First Results from IceCube

    E-Print Network [OSTI]

    Spencer R. Klein; for the IceCube Collaboration

    2006-01-12T23:59:59.000Z

    IceCube is a 1 km$^3$ neutrino observatory being built to study neutrino production in active galactic nuclei, gamma-ray bursts, supernova remnants, and a host of other astrophysical sources. High-energy neutrinos may signal the sources of ultra-high energy cosmic rays. IceCube will also study many particle-physics topics: searches for WIMP annihilation in the Earth or the Sun, and for signatures of supersymmetry in neutrino interactions, studies of neutrino properties, including searches for extra dimensions, and searches for exotica such as magnetic monopoles or Q-balls. IceCube will also study the cosmic-ray composition. In January, 2005, 60 digital optical modules (DOMs) were deployed in the South Polar ice at depths ranging from 1450 to 2450 meters, and 8 ice-tanks, each containing 2 DOMs were deployed as part of a surface air-shower array. All 76 DOMs are collecting high-quality data. After discussing the IceCube physics program and hardware, I will present some initial results with the first DOMs.

  9. Dynamically coupling the non-linear Stokes equations with the Shallow Ice Approximation in glaciology: Description and first applications of the ISCAL method

    E-Print Network [OSTI]

    Ahlkrona, Josefin; Kirchner, Nina; Zwinger, Thomas

    2015-01-01T23:59:59.000Z

    We propose and implement a new method, called the Ice Sheet Coupled Approximation Levels (ISCAL) method, for simulation of ice sheet flow in large domains under long time-intervals. The method couples the exact, full Stokes (FS) equations with the Shallow Ice Approximation (SIA). The part of the domain where SIA is applied is determined automatically and dynamically based on estimates of the modeling error. For a three dimensional model problem where the number of degrees of freedom is comparable to a real world application, ISCAL performs almost an order of magnitude faster with a low reduction in accuracy compared to a monolithic FS. Furthermore, ISCAL is shown to be able to detect rapid dynamic changes in the flow. Three different error estimations are applied and compared. Finally, ISCAL is applied to the Greenland Ice Sheet, proving ISCAL to be a potential valuable tool for the ice sheet modeling community.

  10. Modeling of Antarctic sea ice in a general circulation model

    SciTech Connect (OSTI)

    Wu, Xingren; Budd, W.F. [Antarctic Cooperative Research Centre, Tasmania (Australia)] [Antarctic Cooperative Research Centre, Tasmania (Australia); Simmonds, I. [School of Earth Sciences, Victoria (Australia)] [School of Earth Sciences, Victoria (Australia)

    1997-04-01T23:59:59.000Z

    A dynamic-thermodynamic sea ice model is developed and coupled with the Melbourne University general circulation model to simulate the seasonal cycle of the Antarctic sea ice distributions The model is efficient, rapid to compute, and useful for a range of climate studies. The thermodynamic part of the sea ice model is similar to that developed by Parkinson and Washington, the dynamics contain a simplified ice rheology that resists compression. The thermodynamics is based on energy conservation at the top surface of the ice/snow, the ice/water interface, and the open water area to determine the ice formation, accretion, and ablation. A lead parameterization is introduced with an effective partitioning scheme for freezing between and under the ice floes. The dynamic calculation determines the motion of ice, which is forced with the atmospheric wind, taking account of ice resistance and rafting. The simulated sea ice distribution compares reasonably well with observations. The seasonal cycle of ice extent is well simulated in phase as well as in magnitude. Simulated sea ice thickness and concentration are also in good agreement with observations over most regions and serve to indicate the importance of advection and ocean drift in the determination of the sea ice distribution. 64 refs., 15 figs., 2 tabs.

  11. Quantification of summertime water ice deposition on the Martian north polar ice cap

    E-Print Network [OSTI]

    Brown, Adrian J; Becerra, Patricio; Byrne, Shane

    2015-01-01T23:59:59.000Z

    We use observations from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) of the north polar cap during late summer for two Martian years, to monitor the complete summer cycle of albedo and water ice grain size in order to place quantitative limits of the amount of water ice deposited in late summer. We establish here for the first time the complete spring to summer cycle of water ice grain sizes on the north polar cap. The apparent grain sizes grow until Ls=132, when they appear to shrink again, until they are obscured at the end of summer by the north polar hood. Under the assumption that the shrinking of grain sizes is due to the deposition of find grained ice, we quantify the amount of water ice deposited per Martian boreal summer, and estimate the amount of water ice that must be transported equatorward. Interestingly, we find that the relative amount of water ice deposited in the north cap during boreal summer (0.7-7 microns) is roughly equivalent to the average amount of water ice depos...

  12. Home Atmosphere Sea Ice Ocean Land Greenland Biology Greenland Ice Sheet Mass Balance

    E-Print Network [OSTI]

    Box, Jason E.

    , thinning and breakup of Jakobshavn Glacier's (SW Greenland) floating ice tongue and acceleration-to-year variability in GrIS mass turnover, e.g. sudden glacier accelerations (Rignot and Kanagartnam 2006). Since or 2005. Physical response mechanisms, such as hydraulic acceleration of the ice sheet from continued

  13. ICED'09/148 INTERNATIONAL CONFERENCE ON ENGINEERING DESIGN, ICED'09

    E-Print Network [OSTI]

    Papalambros, Panos

    derived from the diversity of disciplines that contribute to design, including engineering, economics with the usual engineering requirements. This article describes the basic ideas in constructing the designICED'09/148 INTERNATIONAL CONFERENCE ON ENGINEERING DESIGN, ICED'09 24 - 27 AUGUST 2009, STANFORD

  14. Ion Coulomb Crystals

    E-Print Network [OSTI]

    Richard C. Thompson

    2014-11-18T23:59:59.000Z

    Ion Coulomb crystals (ICC), formed by atomic ions at low temperatures in radiofrequency and Penning ion traps, are structures that have remarkable properties and many applications. Images of Coulomb crystals are striking and reveal the crystal structure, which arises from a balance between the trapping forces acting on the ions and their mutual Coulomb repulsion. Applications of these structures range from frequency standards and quantum simulation through to measurement of the cross sections of chemical reactions of ions.

  15. Phononic crystal devices

    DOE Patents [OSTI]

    El-Kady, Ihab F. (Albuquerque, NM); Olsson, Roy H. (Albuquerque, NM)

    2012-01-10T23:59:59.000Z

    Phononic crystals that have the ability to modify and control the thermal black body phonon distribution and the phonon component of heat transport in a solid. In particular, the thermal conductivity and heat capacity can be modified by altering the phonon density of states in a phononic crystal. The present invention is directed to phononic crystal devices and materials such as radio frequency (RF) tags powered from ambient heat, dielectrics with extremely low thermal conductivity, thermoelectric materials with a higher ratio of electrical-to-thermal conductivity, materials with phononically engineered heat capacity, phononic crystal waveguides that enable accelerated cooling, and a variety of low temperature application devices.

  16. Liquid Crystal Optofluidics

    SciTech Connect (OSTI)

    Vasdekis, Andreas E.; Cuennet, J. G.; Psaltis, D.

    2012-10-11T23:59:59.000Z

    By employing anisotropic fluids and namely liquid crystals, fluid flow becomes an additional degree of freedom in designing optofluidic devices. In this paper, we demonstrate optofluidic liquid crystal devices based on the direct flow of nematic liquid crystals in microfluidic channels. Contrary to previous reports, in the present embodiment we employ the effective phase delay acquired by light travelling through flowing liquid crystal, without analysing the polarisation state of the transmitted light. With this method, we demonstrate the variation in the diffraction pattern of an array of microfluidic channels acting as a grating. We also discuss our recent activities in integrating mechanical oscillators for on-chip peristaltic pumping.

  17. Partial rotational lattice order–disorder in stefin B crystals

    SciTech Connect (OSTI)

    Renko, Miha [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, SI-1000 Ljubljana (Slovenia); Taler-Ver?i?, Ajda [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Miheli?, Marko [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, SI-1000 Ljubljana (Slovenia); Žerovnik, Eva [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Turk, Dušan, E-mail: dusan.turk@ijs.si [Josef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Jamova 39, SI-1000 Ljubljana (Slovenia)

    2014-04-01T23:59:59.000Z

    Crystal lattice disorders are a phenomenon which may hamper the determination of macromolecular crystal structures. Using the case of the crystal structure of stefin B, identification of rotational order–disorder and structure determination are described. At present, the determination of crystal structures from data that have been acquired from twinned crystals is routine; however, with the increasing number of crystal structures additional crystal lattice disorders are being discovered. Here, a previously undescribed partial rotational order–disorder that has been observed in crystals of stefin B is described. The diffraction images revealed normal diffraction patterns that result from a regular crystal lattice. The data could be processed in space groups I4 and I422, yet one crystal exhibited a notable rejection rate in the higher symmetry space group. An explanation for this behaviour was found once the crystal structures had been solved and refined and the electron-density maps had been inspected. The lattice of stefin B crystals is composed of five tetramer layers: four well ordered layers which are followed by an additional layer of alternatively placed tetramers. The presence of alternative positions was revealed by the inspection of electron-density score maps. The well ordered layers correspond to the crystal symmetry of space group I422. In addition, the positions of the molecules in the additional layer are related by twofold rotational axes which correspond to space group I422; however, these molecules lie on the twofold axis and can only be related in a statistical manner. When the occupancies of alternate positions and overlapping are equal, the crystal lattice indeed fulfills the criteria of space group I422; when these occupancies are not equal, the lattice only fulfills the criteria of space group I4.

  18. Heat transfer in ice hockey halls: measurements, energy analysis and analytical ice pad temperature profile

    E-Print Network [OSTI]

    Andrea Ferrantelli; Klaus Viljanen

    2015-06-30T23:59:59.000Z

    We consider heat transfer processes in an ice hockey hall, during operating conditions, with a bottom-up approach based upon on-site measurements. Detailed temperature data of both the ice pad and the air above the ice rink are used for a heat balance calculation in the steady-state regime, which quantifies the impact of each single heat source. We solve the heat equation in the ice slab in transient regime, and obtain a general analytical formula for the temperature profile. This solution is then applied to the resurfacing process by using our measurements as (time-dependent) boundary conditions (b.c.), and compared to an analogous numerical computation with good agreement. Our analytical formula is given with implicit initial condition and b.c., therefore it can be used not only in ice halls, but in a large variety of engineering applications.

  19. Heat transfer in ice hockey halls: measurements, energy analysis and analytical ice pad temperature profile

    E-Print Network [OSTI]

    Ferrantelli, Andrea

    2015-01-01T23:59:59.000Z

    We consider heat transfer processes in an ice hockey hall, during operating conditions, with a bottom-up approach based upon on-site measurements. Detailed temperature data of both the ice pad and the air above the ice rink are used for a heat balance calculation in the steady-state regime, which quantifies the impact of each single heat source. We solve the heat equation in the ice slab in transient regime, and obtain a general analytical formula for the temperature profile. This solution is then applied to the resurfacing process by using our measurements as (time-dependent) boundary conditions (b.c.), and compared to an analogous numerical computation with good agreement. Our analytical formula is given with implicit initial condition and b.c., therefore it can be used not only in ice halls, but in a large variety of engineering applications.

  20. The Role of Snow and Ice in the Climate System

    SciTech Connect (OSTI)

    Barry, Roger (NSIDC) [NSIDC

    2007-12-19T23:59:59.000Z

    Global snow and ice cover (the 'cryosphere') plays a major role in global climate and hydrology through a range of complex interactions and feedbacks, the best known of which is the ice - albedo feedback. Snow and ice cover undergo marked seasonal and long term changes in extent and thickness. The perennial elements - the major ice sheets and permafrost - play a role in present-day regional and local climate and hydrology, but the large seasonal variations in snow cover and sea ice are of importance on continental to hemispheric scales. The characteristics of these variations, especially in the Northern Hemisphere, and evidence for recent trends in snow and ice extent are discussed.

  1. Channeling through Bent Crystals

    SciTech Connect (OSTI)

    Mack, Stephanie; /Ottawa U. /SLAC

    2012-09-07T23:59:59.000Z

    Bent crystals have demonstrated potential for use in beam collimation. A process called channeling is when accelerated particle beams are trapped by the nuclear potentials in the atomic planes within a crystal lattice. If the crystal is bent then the particles can follow the bending angle of the crystal. There are several different effects that are observed when particles travel through a bent crystal including dechanneling, volume capture, volume reflection and channeling. With a crystal placed at the edge of a particle beam, part of the fringe of the beam can be deflected away towards a detector or beam dump, thus helping collimate the beam. There is currently FORTRAN code by Igor Yazynin that has been used to model the passage of particles through a bent crystal. Using this code, the effects mentioned were explored for beam energy that would be seen at the Facility for Advanced Accelerator Experimental Tests (FACET) at a range of crystal orientations with respect to the incoming beam. After propagating 5 meters in vacuum space past the crystal the channeled particles were observed to separate from most of the beam with some noise due to dechanneled particles. Progressively smaller bending radii, with corresponding shorter crystal lengths, were compared and it was seen that multiple scattering decreases with the length of the crystal therefore allowing for cleaner detection of the channeled particles. The input beam was then modified and only a portion of the beam sent through the crystal. With the majority of the beam not affected by the crystal, most particles were not deflected and after propagation the channeled particles were seen to be deflected approximately 5mm. After a portion of the beam travels through the crystal, the entire beam was then sent through a quadrupole magnet, which increased the separation of the channeled particles from the remainder of the beam to a distance of around 20mm. A different code, which was developed at SLAC, was used to create an angular profile plot which was compared to what was produced by Yazynin's code for a beam with no multiple scattering. The results were comparable, with volume reflection and channeling effects observed and the range of crystal orientations at which volume reflection is seen was about 1 mrad in both simulations.

  2. Detecting extra-galactic supernova neutrinos in the Antarctic ice

    E-Print Network [OSTI]

    Sebastian Böser; Marek Kowalski; Lukas Schulte; Nora Linn Strotjohann; Markus Voge

    2014-07-28T23:59:59.000Z

    Building on the technological success of the IceCube neutrino telescope, we outline a prospective low-energy extension that utilizes the clear ice of the South Pole. Aiming at a 10 Mton effective volume and a 10 MeV threshold, the detector would provide sufficient sensitivity to detect neutrino bursts from core-collapse supernovae (SNe) in nearby galaxies. The detector geometry and required density of instrumentation are discussed along with the requirements to control the various sources of background, such as solar neutrinos. In particular, the suppression of spallation events induced by atmospheric muons poses a challenge that will need to be addressed. Assuming this background can be controlled, we find that the resulting detector will be able to detect SNe from beyond 10 Mpc, delivering between 10 and 41 regular core-collapse SN detections per decade. It would further allow to study more speculative phenomena, such as optically dark (failed) SNe, where the collapse proceeds directly to a black hole, at a detection rate similar to that of regular SNe. We find that the biggest technological challenge lies in the required number of large area photo-sensors, with simultaneous strict limits on the allowed noise rates. If both can be realized, the detector concept we present will reach the required sensitivity with a comparatively small construction effort and hence offers a route to future routine observations of SNe with neutrinos.

  3. Equations of state of ice VI and ice VII at high pressure and high temperature

    SciTech Connect (OSTI)

    Bezacier, Lucile; Hanfland, Michael [European Synchrotron Radiation Facility, 6 rue Jules Horowitz, 38000 Grenoble (France); Journaux, Baptiste; Perrillat, Jean-Philippe; Cardon, Hervé; Daniel, Isabelle [Laboratoire de Géologie de Lyon, UMR 5276 CNRS, Ecole Normale Supérieure de Lyon – Université Claude Bernard Lyon 1, 2 rue Raphael Dubois, 69622 Villeurbanne Cedex (France)

    2014-09-14T23:59:59.000Z

    High-pressure H{sub 2}O polymorphs among which ice VI and ice VII are abundant in the interiors of large icy satellites and exo-planets. Knowledge of the elastic properties of these pure H{sub 2}O ices at high-temperature and high-pressure is thus crucial to decipher the internal structure of icy bodies. In this study we assess for the first time the pressure-volume-temperature (PVT) relations of both polycrystalline pure ice VI and ice VII at high pressures and temperatures from 1 to 9 GPa and 300 to 450 K, respectively, by using in situ synchrotron X-ray diffraction. The PVT data are adjusted to a second-order Birch-Murnaghan equation of state and give V{sub 0} = 14.17(2) cm{sup 3}?mol{sup ?1}, K{sub 0} = 14.05(23) GPa, and ?{sub 0} = 14.6(14) × 10{sup ?5} K{sup ?1} for ice VI and V{sub 0} = 12.49(1) cm{sup 3}?mol{sup ?1}, K{sub 0} = 20.15(16) GPa, and ?{sub 0} = 11.6(5) × 10{sup ?5} K{sup ?1} for ice VII.

  4. Maneuverability of ships in ice: numerical simulation and comparison with field measurements

    E-Print Network [OSTI]

    Nřrvĺg, Kjetil

    Maneuverability of ships in ice: numerical simulation and comparison with field measurements Biao Su Department of Marine Technology, NTNU May 28, 2013 #12;Motivation Local ice load Global ice load Ship's performance · Ice-hull interaction · Local ice load · Global ice load · Ship's performance #12

  5. Development of the Great Lakes Ice-circulation Model (GLIM): Application to Lake Erie in 20032004

    E-Print Network [OSTI]

    Development of the Great Lakes Ice-circulation Model (GLIM): Application to Lake Erie in 2003: Received 4 May 2009 Accepted 30 November 2009 Communicated by Dr. Ram Yerubandi Index words: Coupled Ice-Ocean Model Ice modeling Lake ice cover Ice thickness Ice speed Lake surface temperature Great Lakes Lake Erie

  6. Numerical simulation of ice-induced loads on ships and comparison with field measurements

    E-Print Network [OSTI]

    Nřrvĺg, Kjetil

    Numerical simulation of ice-induced loads on ships and comparison with field measurements Biao Su Department of Marine Technology, NTNU May 28, 2013 #12;Motivation Local ice load Global ice load Ship's performance · Ice-hull interaction · Local ice load · Global ice load · Ship's performance #12;Outline

  7. Postdoctoral position Antarctic ice sheet modelling Free University of Brussels (VUB)

    E-Print Network [OSTI]

    Huybrechts, Philippe

    systems and ice caps, and in ice sheets in both polar regions (Greenland and Antarctica). The project as improved treatments for basal processes (basal sliding below ice sheet, basal melting below ice shelvesPostdoctoral position ­ Antarctic ice sheet modelling Free University of Brussels (VUB) The Ice

  8. Basal melt rates beneath Whillans Ice Stream, West Antarctica

    E-Print Network [OSTI]

    Beem, Lucas H.; Jezek, Ken C.; Van Der Veen, C. J.

    2010-08-05T23:59:59.000Z

    Basal water lubricates and enables the fast flow of the West Antarctic ice streams which exist under low gravitational driving stress. Identification of sources and rates of basal meltwater production can provide insight into the dynamics of ice...

  9. Study of ice cloud properties using infrared spectral data

    E-Print Network [OSTI]

    Garrett, Kevin James

    2009-05-15T23:59:59.000Z

    The research presented in this thesis involves the study of ice cloud microphysical and optical properties using both hyperspectral and narrowband infrared spectral data. First, ice cloud models are developed for the Infrared Atmospheric Sounding...

  10. arctic ocean ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AD of transient model simulations and a new type of sen- sitivity experiments with artificial sea ice growth Born, Andreas 320 The Thinning of Arctic Sea Ice, 19882003: Have...

  11. Study of ice cloud properties using infrared spectral data 

    E-Print Network [OSTI]

    Garrett, Kevin James

    2009-05-15T23:59:59.000Z

    The research presented in this thesis involves the study of ice cloud microphysical and optical properties using both hyperspectral and narrowband infrared spectral data. First, ice cloud models are developed for the Infrared Atmospheric Sounding...

  12. aircraft icing training: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Completed all Enhanced Hot Water Drill staff from UW, IceCube collaborators, and Raytheon. Conducted a Quarterly Status Meeting at UW-loaded schedule for on-ice...

  13. andrill mcmurdo ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Completed all Enhanced Hot Water Drill staff from UW, IceCube collaborators, and Raytheon. Conducted a Quarterly Status Meeting at UW-loaded schedule for on-ice...

  14. aterrizamiento del ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Completed all Enhanced Hot Water Drill staff from UW, IceCube collaborators, and Raytheon. Conducted a Quarterly Status Meeting at UW-loaded schedule for on-ice...

  15. aircraft icing hazards: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Completed all Enhanced Hot Water Drill staff from UW, IceCube collaborators, and Raytheon. Conducted a Quarterly Status Meeting at UW-loaded schedule for on-ice...

  16. aircraft icing nowcasting: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Completed all Enhanced Hot Water Drill staff from UW, IceCube collaborators, and Raytheon. Conducted a Quarterly Status Meeting at UW-loaded schedule for on-ice...

  17. adsorption ice maker: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Completed all Enhanced Hot Water Drill staff from UW, IceCube collaborators, and Raytheon. Conducted a Quarterly Status Meeting at UW-loaded schedule for on-ice...

  18. ancient 19-m ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Completed all Enhanced Hot Water Drill staff from UW, IceCube collaborators, and Raytheon. Conducted a Quarterly Status Meeting at UW-loaded schedule for on-ice...

  19. IceCube Project Monthly Report -November 2009 Accomplishments

    E-Print Network [OSTI]

    Saffman, Mark

    -speaking researchers. · IceCube participated with Raytheon Polar Services Company in an extremely successful emergency principally due to lower labor and on-ice support costs for Raytheon Polar Services Corporation and the Air

  20. Cirrus cloud formation and the role of heterogeneous ice nuclei

    E-Print Network [OSTI]

    Froyd, Karl D.

    2013-01-01T23:59:59.000Z

    Composition, size, and phase are key properties that define the ability of an aerosol particle to initiate ice in cirrus clouds. Properties of cirrus ice nuclei (IN) have not been well constrained due to a lack of systematic ...

  1. Learn to Skate at UAF Patty Ice Arena

    E-Print Network [OSTI]

    Wagner, Diane

    Learn to Skate at UAF Patty Ice Arena Tots(age 3-6)& Beginners/Pre-Alpha(age 6-up) 4 Sessions for non-members; $20/day Alpha-Freestyle 3:30-5:00pm One year membership to Ice Skating Institute - $15BreakSkatingCamp Skating for Hockey 3:30-5:00pm March 12-15 3:30-3:45 - O -ice:Warm up 4:00-4:45 - On Ice Skills 15 min

  2. Covered Product Category: Water-Cooled Ice Machines

    Broader source: Energy.gov [DOE]

    The Federal Energy Management Program (FEMP) provides acquisition guidance and federal efficiency requirements for water-cooled ice machines.

  3. An update on land-ice modeling in the CESM

    SciTech Connect (OSTI)

    Lipscomb, William H [Los Alamos National Laboratory

    2011-01-18T23:59:59.000Z

    Mass loss from land ice, including the Greenland and Antarctic ice sheets as well as smaller glacier and ice caps, is making a large and growing contribution to global sea-level rise. Land ice is only beginning to be incorporated in climate models. The goal of the Land Ice Working Group (LIWG) is to develop improved land-ice models and incorporate them in CESM, in order to provide useful, physically-based sea-level predictions. LJWG efforts to date have led to the inclusion of a dynamic ice-sheet model (the Glimmer Community Ice Sheet Model, or Glimmer-CISM) in the Community Earth System Model (CESM), which was released in June 2010. CESM also includes a new surface-mass-balance scheme for ice sheets in the Community Land Model. Initial modeling efforts are focused on the Greenland ice sheet. Preliminary results are promising. In particular, the simulated surface mass balance for Greenland is in good agreement with observations and regional model results. The current model, however, has significant limitations: The land-ice coupling is one-way; we are using a serial version of Glimmer-CISM with the shallow-ice approximation; and there is no ice-ocean coupling. During the next year we plan to implement two-way coupling (including ice-ocean coupling with a dynamic Antarctic ice sheet) with a parallel , higher-order version of Glimmer-CISM. We will also add parameterizations of small glaciers and ice caps. With these model improvements, CESM will be able to simulate all the major contributors to 21st century global sea-level rise. Results of the first round of simulations should be available in time to be included in the Fifth Assessment Report (ARS) of the Intergovernmental Panel on Climate Change.

  4. Electron decay at IceCube

    E-Print Network [OSTI]

    Lynch, Morgan H

    2015-01-01T23:59:59.000Z

    In this paper we apply the formalism of Accelerated Quantum Dynamics (AQD) to the radiative stopping of highly relativistic electrons in ice. We compute the lifetime of electrons to decay into muons as well as the spectrum of the emitted muons. The energy of the emitted muon depends on the deceleration of the electron and this correlation can be used to tag the event and confirm the prediction. The results predict the acceleration-induced decay of electrons at IceCube energies. This experimental setting has the potential to establish the existence of the Unruh effect as well investigate the role of high acceleration in particle physics.

  5. Observations: Changes in Snow, Ice and Frozen Ground

    E-Print Network [OSTI]

    Jellinek, Mark

    ................................................ 352 4.4.4 Pack Ice Motion................................................... 355 4.5 Changes4 Observations: Changes in Snow, Ice and Frozen Ground Coordinating Lead Authors: Peter Lemke. Kaser, P. Mote, R.H. Thomas and T. Zhang, 2007: Observations: Changes in Snow, Ice and Frozen Ground. In

  6. Contemporary Lake Superior Ice Cover Climatology Raymond A. Assel

    E-Print Network [OSTI]

    Contemporary Lake Superior Ice Cover Climatology Raymond A. Assel NOAA Great Lakes Environmental Introduction A brief discussion of Lake Superior ice cover climatology (Phillips, 1978) was included) almost three decades ago. Much additional information (and analysis) of Great Lakes ice cover has been

  7. The Integrated Computer Engineering Design (ICED) Curriculum Augustus K. Uht

    E-Print Network [OSTI]

    Uht, Augustus K.

    The Integrated Computer Engineering Design (ICED) Curriculum Augustus K. Uht Department computer engineering curriculum, ICED, is being introduced at the University of Rhode Island. The main. This paper gives the rationale of ICED in depth, and describes the core courses, their activities and use

  8. Ice-Floe Simulation Viewer Tool Justin Adams

    E-Print Network [OSTI]

    Peters, Dennis

    Ice-Floe Simulation Viewer Tool Justin Adams Computer Engineering Memorial University St. John's, Newfoundland dpeters@mun.ca Abstract--We are developing software to simulate the be- haviour of sea ice the ability to set up the initial conditions, run the simulation, and display the simulated ice- floe data

  9. Bacteria beneath the West Antarctic Ice Sheet Brian Lanoil,1

    E-Print Network [OSTI]

    Priscu, John C.

    Bacteria beneath the West Antarctic Ice Sheet Brian Lanoil,1 * Mark Skidmore,1 John C. Priscu,2, particularly those that lie beneath polar ice sheets, are beginning to be recog- nized as an important part Vostok, Antarctica, no sub-ice sheet environments have been shown to support microbial ecosystems. Here

  10. Ice Simulation Using GPGPU Shadi Alawneh and Dennis Peters

    E-Print Network [OSTI]

    Peters, Dennis

    Ice Simulation Using GPGPU Shadi Alawneh and Dennis Peters Electrical and Computer Engineering.alawneh, dpeters}@mun.ca Abstract-- Simulation of the behaviour of a ship operating in pack ice on several different ice fields for several iterations to compare the performance. Our results show speed up

  11. A Computer Tutorial for Great Lakes Ice Cover Climatology

    E-Print Network [OSTI]

    A Computer Tutorial for Great Lakes Ice Cover Climatology R.A. ASSELL U.S. Department of Commerce tutorial was developed to provide an overview of the annual ~ r e a fLakes ice cycle. The tutorial includes an animation to aid in visualizing the normal seasonal progression and the spatial patterns of ice cover

  12. Implementing an ICE: A methodology for the design, development

    E-Print Network [OSTI]

    Deussen, Oliver

    Implementing an ICE: A methodology for the design, development and installation of Interactive for the design, development and implementation of ICEs (Interactive Collaborative Environments) in real world with the Edinburgh Napier ICE, a multi-user, multi-surface, multi-touch blended interaction digitally augmented space

  13. Modeling Lake Erie ice dynamics: Process studies , Haoguo Hu2

    E-Print Network [OSTI]

    Modeling Lake Erie ice dynamics: Process studies Jia Wang1 , Haoguo Hu2 , and Xuezhi Bai2 1 NOAA of Michigan 4840 S. State Road, Ann Arbor, MI 48108 Abstract. A Great Lakes Ice-circulation Model (GLIM derived from meteorological measurements. After the seasonal cycles of ice concentration, thickness

  14. ICE Algorithm for the Shocktube Problem Oren E. Livne

    E-Print Network [OSTI]

    Utah, University of

    1 ICE Algorithm for the Shocktube Problem Oren E. Livne UUSCI-2006-007 Scientific Computing the main ICE advection algorithm for scalar advection problems (advection and Burg- ers step in this original Kashiwa ICE algorithm [Kas00], and its relation of both the Davis scheme [Dav87

  15. A lattice model to simulate ice-structure interaction

    E-Print Network [OSTI]

    Boyer, Edmond

    A lattice model to simulate ice-structure interaction O. Dorival, A. V. Metrikine, A. Simone of Technology P. O. Box 5048, 2600 GA Delft, Netherlands Abstract The interaction between ice sheets, due to the complexity of ice material the use of small-scale experiments is problematic if one aims

  16. Operation and Control of Full Ice-storage System

    E-Print Network [OSTI]

    Liu, Q.; Liu, Y.

    2006-01-01T23:59:59.000Z

    In a dividing time ice-storage system, the refrigerator does not operate during power's on-peak period, and all the cooling is supplied by the ice stored in off-peak period, so that the use of electricity can be maintained. When the ice is thawing...

  17. Global Ice and Land Climate Studies Using Scatterometer Image Data

    E-Print Network [OSTI]

    Long, David G.

    1 Global Ice and Land Climate Studies Using Scatterometer Image Data David G. Long Brigham Young CA 91109 ben@pacific.jpl.nasa.gov Sasan.Saatchi@jpl.nasa.gov Cheryl Bertoia U. S. National Ice Center: Long, D. G., M. R. Drinkwater, B. Holt, S. Saatchi, and C. Bertoia, Global ice and land climate studies

  18. Is the Missing Ultra-Red Material Colorless Ice?

    E-Print Network [OSTI]

    W. M. Grundy

    2008-11-14T23:59:59.000Z

    The extremely red colors of some transneptunian objects and Centaurs are not seen among the Jupiter family comets which supposedly derive from them. Could this mismatch result from sublimation loss of colorless ice? Radiative transfer models show that mixtures of volatile ice and nonvolatile organics could be extremely red, but become progressively darker and less red as the ice sublimates away.

  19. STATE OF CALIFORNIA ICE STORAGE AIR CONDITIONING (ISAC) UNITS

    E-Print Network [OSTI]

    cooling with the compressor). Yes No #12;STATE OF CALIFORNIA ICE STORAGE AIR CONDITIONING (ISAC) UNITS CEC/09) CALIFORNIA ENERGY COMMISSION INSTALLATION CERTIFICATE CF-6R-MECH-08 Ice Storage Air Conditioning (ISAC) Units being full of ice. Verify that the system is operates properly in the Idle mode (i.e., the compressor

  20. THE CONTRIBUTION OF GREENLAND ICE SHEET MELTING TO

    E-Print Network [OSTI]

    THE CONTRIBUTION OF GREENLAND ICE SHEET MELTING TO GLOBAL SEA-LEVEL CHANGE Conor Mc three major sources, the Greenland ice sheet, Antarctica, and other eustatic components. Each has its own predictable spatial signal, and particular attention was paid to the Greenland ice sheet, given

  1. The Ice Rink Problem 1 Bernard M.E. Moret,

    E-Print Network [OSTI]

    Moret, Bernard

    The Ice Rink Problem 1 Bernard M.E. Moret, Michael Collins, Jared Saia, and Ling Yu Department the sensor footprint. A similar task with a simpler geometry consists of cleaning an ice rink. We prove that the method used in ice rinks (the ``Zamboni algorithm'') is optimal and use it to develop heuristics

  2. Integrated navigation for AUV operations under ice shelves

    E-Print Network [OSTI]

    Griffiths, Gwyn

    Integrated navigation for AUV operations under ice shelves Gwyn Griffiths and Steve Mc One-slide summary of the Autosub AUV J Why explore beneath ice shelves? J Technology challenges: the Halliburton `Geosub' #12;Why explore beneath ice shelves? Gl oba l Wa r mi ng Li nke d t o Me l t i ng I c e c

  3. ICE SHEET SOURCES OF SEA LEVEL RISE AND FRESHWATER DISCHARGE

    E-Print Network [OSTI]

    Carlson, Anders

    ICE SHEET SOURCES OF SEA LEVEL RISE AND FRESHWATER DISCHARGE DURING THE LAST DEGLACIATION Anders E the sources of sea level rise and freshwater dis- charge to the global oceans associated with retreat of ice­10 m sea level rise at 19.0­19.5 ka, sourced largely from Northern Hemisphere ice sheet retreat

  4. THE ROLE OF METHANOL IN THE CRYSTALLIZATION OF TITAN'S PRIMORDIAL OCEAN

    SciTech Connect (OSTI)

    Deschamps, Frederic [Institute of Geophysics, Swiss Federal Institute of Technology Zurich, 8092 Zurich (Switzerland); Mousis, Olivier [Universite de Franche-Comte, Institut UTINAM, CNRS/INSU, UMR 6213, 25030 Besancon Cedex (France); Sanchez-Valle, Carmen [Institute of Geochemistry and Petrology, Swiss Federal Institute of Technology Zurich, 8092 Zurich (Switzerland); Lunine, Jonathan I., E-mail: frederic.deschamps@erdw.ethz.c [Dipartimento di Fisica, Universita degli Studi di Roma 'Tor Vergata', Rome (Italy)

    2010-12-01T23:59:59.000Z

    A key parameter that controls the crystallization of primordial oceans in large icy moons is the presence of anti-freeze compounds, which may have maintained primordial oceans over the age of the solar system. Here we investigate the influence of methanol, a possible anti-freeze candidate, on the crystallization of Titan's primordial ocean. Using a thermodynamic model of the solar nebula and assuming a plausible composition of its initial gas phase, we first calculate the condensation sequence of ices in Saturn's feeding zone, and show that in Titan's building blocks methanol can have a mass fraction of {approx}4 wt% relative to water, i.e., methanol can be up to four times more abundant than ammonia. We then combine available data on the phase diagram of the water-methanol system and scaling laws derived from thermal convection to estimate the influence of methanol on the dynamics of the outer ice I shell and on the heat transfer through this layer. For a fraction of methanol consistent with the building blocks composition we determined, the vigor of convection in the ice I shell is strongly reduced. The effect of 5 wt% methanol is equivalent to that of 3 wt% ammonia. Thus, if methanol is present in the primordial ocean of Titan, the crystallization may stop, and a sub-surface ocean may be maintained between the ice I and high-pressure ice layers. A preliminary estimate indicates that the presence of 4 wt% methanol and 1 wt% ammonia may result in an ocean of thickness at least 90 km.

  5. Historical and future black carbon deposition on the three ice caps: Ice core measurements and model simulations from 1850 to 2100

    E-Print Network [OSTI]

    Historical and future black carbon deposition on the three ice caps: Ice core measurements black carbon deposition on the three ice caps: Ice core measurements and model simulations from 1850 tends to enhance snow and ice melting due to the absorption caused by the increased BC deposition

  6. Sublimation rate of molecular crystals - role of internal degrees of freedom

    SciTech Connect (OSTI)

    Maiti, A; Zepeda-Ruiz, L A; Gee, R H; Burnham, A

    2007-01-19T23:59:59.000Z

    It is a common practice to estimate site desorption rate from crystal surfaces with an Arrhenius expression of the form v{sub eff} exp(-{Delta}E/k{sub B}T), where {Delta}E is an activation barrier to desorb and v{sub eff} is an effective vibrational frequency {approx} 10{sup 12} sec{sup -1}. However, such a formula can lead to several to many orders of magnitude underestimation of sublimation rates in molecular crystals due to internal degrees of freedom. We carry out a quantitative comparison of two energetic molecular crystals with crystals of smaller entities like ice and Argon (solid) and uncover the errors involved as a function of molecule size. In the process, we also develop a formal definition of v{sub eff} and an accurate working expression for equilibrium vapor pressure.

  7. Total reflection infrared spectroscopy of water-ice and frozen aqueous NaCl solutions

    SciTech Connect (OSTI)

    Walker, Rachel L.; Searles, Keith; Willard, Jesse A.; Michelsen, Rebecca R. H., E-mail: RMichelsen@rmc.edu [Department of Chemistry, Randolph-Macon College, P.O. Box 5005, Ashland, Virginia 23005 (United States)] [Department of Chemistry, Randolph-Macon College, P.O. Box 5005, Ashland, Virginia 23005 (United States)

    2013-12-28T23:59:59.000Z

    Liquid-like and liquid water at and near the surface of water-ice and frozen aqueous sodium chloride films were observed using attenuated total reflection infrared spectroscopy (ATR-IR). The concentration of NaCl ranged from 0.0001 to 0.01 M and the temperature varied from the melting point of water down to 256 K. The amount of liquid brine at the interface of the frozen films with the germanium ATR crystal increased with salt concentration and temperature. Experimental spectra are compared to reflection spectra calculated for a simplified morphology of a uniform liquid layer between the germanium crystal and the frozen film. This morphology allows for the amount of liquid observed in an experimental spectrum to be converted to the thickness of a homogenous layer with an equivalent amount of liquid. These equivalent thickness ranges from a nanometer for water-ice at 260 K to 170 nm for 0.01 M NaCl close to the melting point. The amounts of brine observed are over an order of magnitude less than the total liquid predicted by equilibrium thermodynamic models, implying that the vast majority of the liquid fraction of frozen solutions may be found in internal inclusions, grain boundaries, and the like. Thus, the amount of liquid and the solutes dissolved in them that are available to react with atmospheric gases on the surfaces of snow and ice are not well described by thermodynamic equilibrium models which assume the liquid phase is located entirely at the surface.

  8. Dynamics and energetics of the cloudy boundary layer in simulations of off-ice flow in the marginal ice zone

    E-Print Network [OSTI]

    Harrington, Jerry Y.

    kinetic energy even in the present case where very strong surface heat fluxes occur. Ice-phase. Inclusion of the ice phase significantly affected the radiative budget as compared to purely liquid clouds, illustrating the importance of ice-phase­radiative couplings for accurate simulations of arctic clouds

  9. Where might we find evidence of a Last Interglacial West Antarctic Ice Sheet collapse in Antarctic ice core records?

    E-Print Network [OSTI]

    Siddall, Mark

    increased melting from valley glaciers and small ice caps (estimated ~0.6±0.1 m, Radi and Hock, 2010), oceanWhere might we find evidence of a Last Interglacial West Antarctic Ice Sheet collapse in Antarctic ice core records? S.L. Bradley a, , M. Siddall a , G.A. Milne b , V. Masson-Delmotte c , E. Wolff d

  10. Decadal-scale variations in ice flow along Whillans Ice Stream and its tributaries, West Antarctica

    E-Print Network [OSTI]

    Stearns, Leigh; Jezek, K.A.; Van der Veen, C.J.

    2005-01-01T23:59:59.000Z

    We investigate velocity changes occurring along Whillans Ice Stream (WIS) by comparing velocities derived from repeat aerial photographs acquired in 1985–89 (average date of 1987) to interferometric satellite radar (InSAR) velocities collected...

  11. Focused synthetic aperture radar processing of ice-sounder data collected over the Greenland ice sheet

    E-Print Network [OSTI]

    Legarsky, J.; Gogineni, Sivaprasad; Akins, T. L.

    2001-10-01T23:59:59.000Z

    We developed a synthetic aperture radar (SAR) processing algorithm for airborne/spaceborne ice-sounding radar systems and applied it to data collected in Greenland. By using focused SAR (phase-corrected coherent averaging), we improved along...

  12. Ice surfaces: macroscopic effects of microscopic structure

    E-Print Network [OSTI]

    Wettlaufer, John S.

    in the large tropical and subtropical belt, and between -20 and -40 C in the small polar caps. Water becomes ice at just around the middle of that temperature range. Only a small shift in temperature determines microphysics and chemistry have large-scale consequences. The difficulties associated with observing processes

  13. Ocean Atmosphere Sea Ice Soil User's Guide

    E-Print Network [OSTI]

    OASIS3 Ocean Atmosphere Sea Ice Soil User's Guide oasis3 prism 2­2, June 2004 Sophie Valcke 1 to realize a coupled simulation with OASIS3. The aim of OASIS3 is to provide a flexible and user friendly. OASIS3 synchronizes the exchanges of coupling fields between the models being coupled, and performs 2D

  14. Ocean Atmosphere Sea Ice Soil User's Guide

    E-Print Network [OSTI]

    OASIS3 Ocean Atmosphere Sea Ice Soil User's Guide oasis3 prism 2­3, August 2004 Sophie Valcke 1 to realize a coupled simulation with OASIS3. The aim of OASIS3 is to provide a flexible and user friendly. OASIS3 synchronizes the exchanges of coupling fields between the models being coupled, and performs 2D

  15. Ocean Atmosphere Sea Ice Soil User's Guide

    E-Print Network [OSTI]

    OASIS 2.0 Ocean Atmosphere Sea Ice Soil User's Guide and Reference Manual November 1995 Laurent for the straightforward use of OASIS 2.0. As far as we know, it is the best way to use it! The aim of OASIS is to provide been particularly emphasized in the OASIS design. The use of OASIS does not change the way the models

  16. IceCube Project Monthly Report Accomplishments

    E-Print Network [OSTI]

    Saffman, Mark

    .2% complete, as measured using earned value techniques. The contingency % of the remaining work is 28.3%. #12 with critical dates and activities managed by both Raytheon Polar Services Company and the UW is set Division Management, and FY08 Actual costs for On-Ice Support that were less than planned. 5/31/08 Change

  17. IceCube Project Monthly Report Accomplishments

    E-Print Network [OSTI]

    Saffman, Mark

    versus the planned performance of 55.8% complete as measured using earned value techniques. The earned safety training for drilling and installation managers, safety leads and a few other on- ice personnel Project Cost $274.3 Value of Foreign Contributions $32.2 NSF Funding $242.1 Contingency as % of Remaining

  18. Largest Ice-Bank Promotes Load Management

    E-Print Network [OSTI]

    Brarmann, G. L.

    1983-01-01T23:59:59.000Z

    of both the 30-year old, 265,000 square foot facility and the new 156,000 square foot Fred L. Hartley Research Center. The energy and demand savings resulting from the installation of the ice-bank system are significant. Large commercial and industrial...

  19. Toward Extraplanetary Under-Ice Exploration

    E-Print Network [OSTI]

    Eustice, Ryan

    .jhu@gmail.com Ryan Eustice Department of Naval Architecture and Marine Engineering University of Michigan Ann Arbor· · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · Toward Extraplanetary Under-Ice@whoi.edu, rsohn@whoi.edu, ssingh@whoi.edu Taichi Sato Ocean Research Institute University of Tokyo Nakano, Tokyo

  20. SINGLE CRYSTAL NEUTRON DIFFRACTION.

    SciTech Connect (OSTI)

    KOETZLE,T.F.

    2001-03-13T23:59:59.000Z

    Single-crystal neutron diffraction measures the elastic Bragg reflection intensities from crystals of a material, the structure of which is the subject of investigation. A single crystal is placed in a beam of neutrons produced at a nuclear reactor or at a proton accelerator-based spallation source. Single-crystal diffraction measurements are commonly made at thermal neutron beam energies, which correspond to neutron wavelengths in the neighborhood of 1 Angstrom. For high-resolution studies requiring shorter wavelengths (ca. 0.3-0.8 Angstroms), a pulsed spallation source or a high-temperature moderator (a ''hot source'') at a reactor may be used. When complex structures with large unit-cell repeats are under investigation, as is the case in structural biology, a cryogenic-temperature moderator (a ''cold source'') may be employed to obtain longer neutron wavelengths (ca. 4-10 Angstroms). A single-crystal neutron diffraction analysis will determine the crystal structure of the material, typically including its unit cell and space group, the positions of the atomic nuclei and their mean-square displacements, and relevant site occupancies. Because the neutron possesses a magnetic moment, the magnetic structure of the material can be determined as well, from the magnetic contribution to the Bragg intensities. This latter aspect falls beyond the scope of the present unit; for information on magnetic scattering of neutrons see Unit 14.3. Instruments for single-crystal diffraction (single-crystal diffractometers or SCDs) are generally available at the major neutron scattering center facilities. Beam time on many of these instruments is available through a proposal mechanism. A listing of neutron SCD instruments and their corresponding facility contacts is included in an appendix accompanying this unit.

  1. Modeling the Fracture of Ice Sheets on Parallel Computers

    SciTech Connect (OSTI)

    Waisman, Haim [Columbia University] [Columbia University; Tuminaro, Ray [Sandia National Labs] [Sandia National Labs

    2013-10-10T23:59:59.000Z

    The objective of this project was to investigate the complex fracture of ice and understand its role within larger ice sheet simulations and global climate change. This objective was achieved by developing novel physics based models for ice, novel numerical tools to enable the modeling of the physics and by collaboration with the ice community experts. At the present time, ice fracture is not explicitly considered within ice sheet models due in part to large computational costs associated with the accurate modeling of this complex phenomena. However, fracture not only plays an extremely important role in regional behavior but also influences ice dynamics over much larger zones in ways that are currently not well understood. To this end, our research findings through this project offers significant advancement to the field and closes a large gap of knowledge in understanding and modeling the fracture of ice sheets in the polar regions. Thus, we believe that our objective has been achieved and our research accomplishments are significant. This is corroborated through a set of published papers, posters and presentations at technical conferences in the field. In particular significant progress has been made in the mechanics of ice, fracture of ice sheets and ice shelves in polar regions and sophisticated numerical methods that enable the solution of the physics in an efficient way.

  2. West antarctic ice sheet collapse: Chimera or clear danger

    SciTech Connect (OSTI)

    Alley, R.B. (Pennsylvania State Univ., University Park, PA (United States)); MacAyeal, D.R. (Univ. of Chicago, IL (United States))

    1993-01-01T23:59:59.000Z

    The specter of a west antarctic collapse has been with us for 25 years. Recently, certain official assessments concerned primarily with the future response to projected global warming have concluded that Antarctica will not cause much sea-level rise within the planning horizon of a century or so. At the same time startling new results on ice sheet (in)stability have been emerging, pointing to less stability then previously believed. Some recent results are reviewed briefly: Heinrich layers in the North Atlantic show basally lubricated surges of the Laurentide ice sheet; the west antarctic ice sheet collapsed recently; the modern west antarctic ice sheet is changing rapidly locally; the bed of ice stream B is exceptionally well lubricated by water and water-saturated soft sediments; the modern ice sheet is thinning slowly on average; a model west antarctic ice sheet undergoes rapid collapses long after forcing and probably related to penetration of warmth to the bed. 23 refs.

  3. Determining Greenland Ice Sheet sensitivity to regional climate change: one-way coupling of a 3-D thermo-mechanical ice sheet model with a mesoscale climate model

    E-Print Network [OSTI]

    Schlegel, Nicole-Jeanne

    2011-01-01T23:59:59.000Z

    Jakobshavn I. Rinks Observed Historic Flux (km 3 ice/year)I. Rinks * Outlets fed by the Northeast Greenland Ice StreamRinks, measured in 2000). Figure 3.1: Steady-state (A) topography (m) and (C) ice

  4. Growing intermetallic single crystals using in situ decanting

    SciTech Connect (OSTI)

    Petrovic, Cedomir; Canfield, Paul; Mellen, Jonathan

    2012-05-16T23:59:59.000Z

    High temperature metallic solution growth is one of the most successful and versatile methods for single crystal growth, and is particularly suited for exploratory synthesis. The method commonly utilizes a centrifuge at room temperature and is very successful for the synthesis of single crystal phases that can be decanted from the liquid below the melting point of the silica ampoule. In this paper, we demonstrate the extension of this method that enables single crystal growth and flux decanting inside the furnace at temperatures above 1200°C. This not only extends the number of available metallic solvents that can be used in exploratory crystal growth but also can be particularly well suited for crystals that have a rather narrow exposed solidification surface in the equilibrium alloy phase diagram.

  5. Global Simulations of Ice nucleation and Ice Supersaturation with an Improved Cloud Scheme in the Community Atmosphere Model

    SciTech Connect (OSTI)

    Gettelman, A.; Liu, Xiaohong; Ghan, Steven J.; Morrison, H.; Park, Sungsu; Conley, Andrew; Klein, Stephen A.; Boyle, James; Mitchell, David; Li, J-L F.

    2010-09-28T23:59:59.000Z

    A process-based treatment of ice supersaturation and ice-nucleation is implemented in the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM). The new scheme is designed to allow (1) supersaturation with respect to ice, (2) ice nucleation by aerosol particles and (3) ice cloud cover consistent with ice microphysics. The scheme is implemented with a 4-class 2 moment microphysics code and is used to evaluate ice cloud nucleation mechanisms and supersaturation in CAM. The new model is able to reproduce field observations of ice mass and mixed phase cloud occurrence better than previous versions of the model. Simulations indicate heterogeneous freezing and contact nucleation on dust are both potentially important over remote areas of the Arctic. Cloud forcing and hence climate is sensitive to different formulations of the ice microphysics. Arctic radiative fluxes are sensitive to the parameterization of ice clouds. These results indicate that ice clouds are potentially an important part of understanding cloud forcing and potential cloud feedbacks, particularly in the Arctic.

  6. Molecular Dynamics Simulations of CO2 Formation in Interstellar Ices

    E-Print Network [OSTI]

    Arasa, Carina; van Dishoeck, Ewine F; Kroes, Geert-Jan

    2013-01-01T23:59:59.000Z

    CO2 ice is one of the most abundant components in ice-coated interstellar ices besides H2O and CO, but the most favorable path to CO2 ice is still unclear. Molecular dynamics calculations on the ultraviolet photodissociation of different kinds of CO-H2O ice systems have been performed at 10 K in order to demonstrate that the reaction between CO and an OH molecule resulting from H2O photodissociation through the first excited state is a possible route to form CO2 ice. However, our calculations, which take into account different ice surface models, suggest that there is another product with a higher formation probability ((3.00+-0.07)x10-2), which is the HOCO complex, whereas the formation of CO2 has a probability of only (3.6+-0.7)x10-4. The initial location of the CO is key to obtain reaction and form CO2: the CO needs to be located deep into the ice. The HOCO complex becomes trapped in the cold ice surface in the trans-HOCO minimum because it quickly loses its internal energy to the surrounding ice, preventi...

  7. Phonon manipulation with phononic crystals.

    SciTech Connect (OSTI)

    Kim Bongsang; Hopkins, Patrick Edward; Leseman, Zayd C.; Goettler, Drew F.; Su, Mehmet F. (University of New Mexico, Albuquerque, NM); El-Kady, Ihab Fathy; Reinke, Charles M.; Olsson, Roy H., III

    2012-01-01T23:59:59.000Z

    In this work, we demonstrated engineered modification of propagation of thermal phonons, i.e. at THz frequencies, using phononic crystals. This work combined theoretical work at Sandia National Laboratories, the University of New Mexico, the University of Colorado Boulder, and Carnegie Mellon University; the MESA fabrication facilities at Sandia; and the microfabrication facilities at UNM to produce world-leading control of phonon propagation in silicon at frequencies up to 3 THz. These efforts culminated in a dramatic reduction in the thermal conductivity of silicon using phononic crystals by a factor of almost 30 as compared with the bulk value, and about 6 as compared with an unpatterned slab of the same thickness. This work represents a revolutionary advance in the engineering of thermoelectric materials for optimal, high-ZT performance. We have demonstrated the significant reduction of the thermal conductivity of silicon using phononic crystal structuring using MEMS-compatible fabrication techniques and in a planar platform that is amenable to integration with typical microelectronic systems. The measured reduction in thermal conductivity as compared to bulk silicon was about a factor of 20 in the cross-plane direction [26], and a factor of 6 in the in-plane direction. Since the electrical conductivity was only reduced by a corresponding factor of about 3 due to the removal of conductive material (i.e., porosity), and the Seebeck coefficient should remain constant as an intrinsic material property, this corresponds to an effective enhancement in ZT by a factor of 2. Given the number of papers in literature devoted to only a small, incremental change in ZT, the ability to boost the ZT of a material by a factor of 2 simply by reducing thermal conductivity is groundbreaking. The results in this work were obtained using silicon, a material that has benefitted from enormous interest in the microelectronics industry and that has a fairly large thermoelectric power factor. In addition, the techniques and scientific understanding developed in the research can be applied to a wide range of materials, with the caveat that the thermal conductivity of such a material be dominated by phonon, rather than electron, transport. In particular, this includes several thermoelectric materials with attractive properties at elevated temperatures (i.e., greater than room temperature), such as silicon germanium and silicon carbide. It is reasonable that phononic crystal patterning could be used for high-temperature thermoelectric devices using such materials, with applications in energy scavenging via waste-heat recovery and thermoelectric cooling for high-performance microelectronic circuits. The only part of the ZT picture missing in this work was the experimental measurement of the Seebeck coefficient of our phononic crystal devices. While a first-order approximation indicates that the Seebeck coefficient should not change significantly from that of bulk silicon, we were not able to actually verify this assumption within the timeframe of the project. Additionally, with regards to future high-temperature applications of this technology, we plan to measure the thermal conductivity reduction factor of our phononic crystals as elevated temperatures to confirm that it does not diminish, given that the nominal thermal conductivity of most semiconductors, including silicon, decreases with temperature above room temperature. We hope to have the opportunity to address these concerns and further advance the state-of-the-art of thermoelectric materials in future projects.

  8. Large Scale Ice Water Path and 3-D Ice Water Content

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Liu, Guosheng

    Cloud ice water concentration is one of the most important, yet poorly observed, cloud properties. Developing physical parameterizations used in general circulation models through single-column modeling is one of the key foci of the ARM program. In addition to the vertical profiles of temperature, water vapor and condensed water at the model grids, large-scale horizontal advective tendencies of these variables are also required as forcing terms in the single-column models. Observed horizontal advection of condensed water has not been available because the radar/lidar/radiometer observations at the ARM site are single-point measurement, therefore, do not provide horizontal distribution of condensed water. The intention of this product is to provide large-scale distribution of cloud ice water by merging available surface and satellite measurements. The satellite cloud ice water algorithm uses ARM ground-based measurements as baseline, produces datasets for 3-D cloud ice water distributions in a 10 deg x 10 deg area near ARM site. The approach of the study is to expand a (surface) point measurement to an (satellite) areal measurement. That is, this study takes the advantage of the high quality cloud measurements at the point of ARM site. We use the cloud characteristics derived from the point measurement to guide/constrain satellite retrieval, then use the satellite algorithm to derive the cloud ice water distributions within an area, i.e., 10 deg x 10 deg centered at ARM site.

  9. Searching for sterile neutrinos in ice

    E-Print Network [OSTI]

    Soebur Razzaque; A. Yu. Smirnov

    2011-07-04T23:59:59.000Z

    Oscillation interpretation of the results from the LSND, MiniBooNE and some other experiments requires existence of sterile neutrino with mass $\\sim 1$ eV and mixing with the active neutrinos $|U_{\\mu 0}|^2 \\sim (0.02 - 0.04)$. It has been realized some time ago that existence of such a neutrino affects significantly the fluxes of atmospheric neutrinos in the TeV range which can be tested by the IceCube Neutrino Observatory. In view of the first IceCube data release we have revisited the oscillations of high energy atmospheric neutrinos in the presence of one sterile neutrino. Properties of the oscillation probabilities are studied in details for various mixing schemes both analytically and numerically. The energy spectra and angular distributions of the $\

  10. Under consideration for publication in J. Fluid Mech. 1 Ocean waves and ice sheets

    E-Print Network [OSTI]

    Craster, Richard

    ; Wadhams & Holt, 1991) to pack ice (Robin, 1963) and even glacial ice tongues (Holdsworth, 1969; Squire etUnder consideration for publication in J. Fluid Mech. 1 Ocean waves and ice sheets By N. J waves incident on ice­covered ocean. The ice cover is idealized as a plate of elastic material for which

  11. Evidence for atmospheric control of sea-ice motion through Nares Strait

    E-Print Network [OSTI]

    Kurapov, Alexander

    Arctic pack ice, a critical element of the global climate system. The general flow of seawater through be sufficient to halt ice drift, despite strong forcing. Pack ice often consolidates in winter behind an ice mobility of pack ice in Fram Strait and the more persistently static conditions in the western CAA. We

  12. Evaluation of Arctic sea ice thickness simulated by Arctic Ocean Model Intercomparison Project models

    E-Print Network [OSTI]

    Zhang, Jinlun

    of fast ice formation and growth. Instead, the modeled fast ice is replaced with pack ice which driftsEvaluation of Arctic sea ice thickness simulated by Arctic Ocean Model Intercomparison Project with estimates of sea ice thickness derived from pan-Arctic satellite freeboard measurements (2004

  13. Classification of Annual Great Lakes Ice Cycles: Winters of 19732002* RAYMOND A. ASSEL

    E-Print Network [OSTI]

    Classification of Annual Great Lakes Ice Cycles: Winters of 1973­2002* RAYMOND A. ASSEL National (Manuscript received 12 July 2004, in final form 13 June 2005) ABSTRACT Annual seasonal average ice cover from 1973 to 2002 and associated dates of first ice, last ice, and ice duration are presented and discussed

  14. MCM LTER METADATA FILE TITLE: Lake ice thickness in the McMurdo Dry Valleys

    E-Print Network [OSTI]

    Priscu, John C.

    MCM LTER METADATA FILE TITLE: Lake ice thickness in the McMurdo Dry Valleys ABSTRACT: Ice thickness was measured from the bottom of the ice cover to the piezometric water level and to the top of the ice cover-2360 achiuchiolo@montana.edu VARIABLES: Location Name, Location Code, Limno Run, Collection Date, z-water, z-ice, z

  15. NOAA Technical Memorandum ERL GLERL-48 LAKE ERIE REGIONAL ICE COVER ANALYSIS: PRELIMINARY RESULTS

    E-Print Network [OSTI]

    NOAA Technical Memorandum ERL GLERL-48 LAKE ERIE REGIONAL ICE COVER ANALYSIS: PRELIMINARY RESULTS R.2 2.3 2.4 2.5 Observation density Average regional ice cover Percentage exceedance from average regional ice cover for discrete ice cover values Contour analysis of percentage ice cover exceedance

  16. Polar Sea Ice Mapping Using SeaWinds Data Hyrum S. Anderson and David G. Long

    E-Print Network [OSTI]

    Long, David G.

    Polar Sea Ice Mapping Using SeaWinds Data Hyrum S. Anderson and David G. Long Brigham Young for mapping polar sea ice extent. In this study, a new al- gorithm for polar sea ice mapping is developed of Bayes detection to produce sea ice extent maps. Statistical models for sea ice and ocean are represented

  17. ORIGINAL PAPER Sedimentary pellets as an ice-cover proxy in a High Arctic

    E-Print Network [OSTI]

    Vincent, Warwick F.

    ORIGINAL PAPER Sedimentary pellets as an ice-cover proxy in a High Arctic ice-covered lake Jessica-cover extent and dynamics on this perennially ice-covered, High Arctic lake. These pellets are interpreted growth. The pellets remain frozen in the ice until a summer or series of summers with reduced ice cover

  18. NAO influence on net sea ice production and exchanges in the Arctic region

    E-Print Network [OSTI]

    Hu, Aixue

    NAO influence on net sea ice production and exchanges in the Arctic region Aixue Hu National Center of the net sea ice production and the sea ice exchanges between the Arctic and its adjacent seas are studied) is the major factor controlling the net sea ice production in the Arctic region since a thinning ice cover

  19. Holocene-Late Pleistocene Climatic Ice Core Records from Qinghai-Tibetan Plateau

    E-Print Network [OSTI]

    Howat, Ian M.

    for affecting large-scale climate. In 1987, three ice cores were recovered to bedrock from the Dunde ice cap. XIE Three ice cores to bedrock from the Dunde ice cap on the north-central Qinghai- Tibetan Plateau of ago. T HE DUNDE ICE CAP (38°06'N, 96°24'E) is located in a desert envi- ronment between the highest

  20. XXII ICTAM, 2529 August 2008, Adelaide, Australia EXPERIMENTAL AND THEORETICAL MODELLING OF ICE SHEETSHELF GROUNDING

    E-Print Network [OSTI]

    Worster, M. Grae

    melting of the polar ice caps due to global warming, a dynamical collapse of the ice sheets has the dynamical stability of shelving ice sheets. INTRODUCTION The Antarctic ice cap contains several tensXXII ICTAM, 25­29 August 2008, Adelaide, Australia EXPERIMENTAL AND THEORETICAL MODELLING OF ICE

  1. Melting of small Arctic ice caps observed from ERS scatterometer time series

    E-Print Network [OSTI]

    Smith, Laurence C.

    Melting of small Arctic ice caps observed from ERS scatterometer time series Laurence C. Smith,1 of melt onset can be observed over small ice caps, as well as the major ice sheets and multi-year sea ice for 14 small Arctic ice caps from 1992­2000. Interannual and regional variability in the timing of melt

  2. Contractor SOW Template - ICE | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative FuelsNovember 13, 2014 BuildingEnergyEnergyConsortiumContacts Contacts2012ICE

  3. Frequency doubling crystals

    DOE Patents [OSTI]

    Wang, Francis (Danville, CA); Velsko, Stephan P. (Livermore, CA)

    1989-01-01T23:59:59.000Z

    A systematic approach to the production of frequency conversion crystals is described in which a chiral molecule has attached to it a "harmonic generating unit" which contributes to the noncentrosymmetry of the molecule. Certain preferred embodiments of such harmonic generating units include carboxylate, guanadyly and imidazolyl units. Certain preferred crystals include L-arginine fluoride, deuterated L-arginine fluoride, L-arginine chloride monohydrate, L-arginine acetate, dithallium tartrate, ammonium N-acetyl valine, N-acetyl tyrosine and N-acetyl hydroxyproline. Chemical modifications of the chiral molecule, such as deuteration, halogenation and controlled counterion substitution are available to adapt the dispersive properties of a crystal in a particular wavelength region.

  4. JOURNAL DE PHYSIQUE Colloque C1, supplement au no 3, Tome 48, mars 1987

    E-Print Network [OSTI]

    Boyer, Edmond

    Abstract : A number of attempts have been made to find the protonic phot~~~nductivityof ice (abbreviated ice single crystals by a xenon lamp and concluded that the probability of photodissociation of ice was observed in ice doped with o- nitrobenzoaldehyde (abbreviated as NBAld ; ice was gram from aquaus solution

  5. Exploring the Earth matter effect with atmospheric neutrinos in ice

    E-Print Network [OSTI]

    Sanjib Kumar Agarwalla; Tracey Li; Olga Mena; Sergio Palomares-Ruiz

    2012-12-10T23:59:59.000Z

    We study the possibility to perform neutrino oscillation tomography and to determine the neutrino mass hierarchy in kilometer-scale ice Cerenkov detectors by means of the theta13-driven matter effects which occur during the propagation of atmospheric neutrinos deep through the Earth. We consider the ongoing IceCube/DeepCore neutrino observatory and future planned extensions, such as the PINGU detector, which has a lower energy threshold. Our simulations include the impact of marginalization over the neutrino oscillation parameters and a fully correlated systematic uncertainty on the total number of events. For the current best-fit value of the mixing angle theta13, the DeepCore detector, due to its relatively high-energy threshold, could only be sensitive to fluctuations on the normalization of the Earth's density of \\Delta\\rho \\simeq \\pm 10% at ~ 1.6 sigma CL after 10 years in the case of a true normal hierarchy. For the two PINGU configurations we consider, overall density fluctuations of \\Delta\\rho \\simeq \\pm 3% (\\pm 2%) could be measured at the 2 sigma CL after 10 years, also in the case of a normal mass hierarchy. We also compare the prospects to determine the neutrino mass hierarchy in these three configurations and find that this could be achieved at the 5 sigma CL, for both hierarchies, after 5 years in DeepCore and about 1 year in PINGU. This clearly shows the importance of lowering the energy threshold below 10 GeV so that detectors are fully sensitive to the resonant matter effects.

  6. A radio air shower surface detector as an extension for IceCube and IceTop

    E-Print Network [OSTI]

    J. Auffenberg; T. Gaisser; K. Helbing; T. Huege; T. Karg; A. Karle

    2007-08-24T23:59:59.000Z

    The IceCube neutrino detector is built into the Antarctic ice sheet at the South Pole to measure high energy neutrinos. For this, 4800 photomultiplier tubes (PMTs) are being deployed at depths between 1450 and 2450 meters into the ice to measure neutrino induced charged particles like muons. IceTop is a surface air shower detector consisting of 160 Cherenkov ice tanks located on top of IceCube. To extend IceTop, a radio air shower detector could be built to significantly increase the sensitivity at higher shower energies and for inclined showers. As air showers induced by cosmic rays are a major part of the muonic background in IceCube, IceTop is not only an air shower detector, but also a veto to reduce the background in IceCube. Air showers are detectable by radio signals with a radio surface detector. The major emission process is the coherent synchrotron radiation emitted by e+ e- shower particles in the Earths magnetic field (geosynchrotron effect). Simulations of the expected radio signals of air showers are shown. The sensitivity and the energy threshold of different antenna field configurations are estimated.

  7. On water ice formation in interstellar clouds

    E-Print Network [OSTI]

    Renaud Papoular

    2005-07-06T23:59:59.000Z

    A model is proposed for the formation of water ice mantles on grains in interstellar clouds. This occurs by direct accretion of monomers from the gas, be they formed by gas or surface reactions. The model predicts the existence of a threshold in interstellar light extinction, A(v), which is mainly determined by the adsorption energy of water molecules on the grain material; for hydrocarbon material, chemical simulation places this energy between 0.5 and 2 kcal/mole, which sets the visible exctinction threshold at a few magnitudes, as observed. Once the threshold is crossed, all available water molecules in the gas are quickly adsorbed, forming an ice mantle, because the grain cools down and the adsorption energy on ice is higher than on bare grain. The model also predicts that the thickness of the mantle, and, hence, the optical thickness at 3 mu, grow linearly with A(v), as observed, with a slope which depends upon the total amount of water in the gas. Chemical simulation was also used to determine the adsorption sites and energies of O and OH on hydrocarbons, and study the dynamics of formation of water molecules by surface reactions with gaseous H atoms, as well as their chances of sticking in situ.

  8. Analytical determination of propeller performance degradation due to ice accretion

    E-Print Network [OSTI]

    Miller, Thomas Lloyd

    1984-01-01T23:59:59.000Z

    result of exposing an airfoil in forward motion to supercooled water droplets in a sub-freezing environment. The type of ice which will form may be determined by a variety of factors including freestream velocity, liquid water content of the cloud... as rime ice, occurs at relatively low velocities, low liquid water content values (typically 0. 5 to 1. 0 grams per cubic meter), and temperature well below freezing. Due primarily to the very cold temperatures associated with rime ice formation...

  9. Calibration and Characterization of the IceCube Photomultiplier Tube

    E-Print Network [OSTI]

    Abbasi, R.

    2010-01-01T23:59:59.000Z

    Calibration and Characterization of the IceCubeUniversity of California. Calibration and Characterizationchar- acterization and calibration of these PMTs before

  10. Optimal Control of Harvesting Ice Thermal Storage Systems

    E-Print Network [OSTI]

    Knebel, D. E.

    1988-01-01T23:59:59.000Z

    for optimal control of a harvesting ice storage system. A simplified procedure is used to develop 24 hour load data. Example installations will be shown....

  11. Covered Product Category: Air-Cooled Ice Machines

    Broader source: Energy.gov [DOE]

    The Federal Energy Management Program (FEMP) provides acquisition guidance for air-cooled ice machines, which are covered by the ENERGY STAR program.

  12. Artificial Spin Ice - A New Playground to Better Understand Magnetism...

    Office of Science (SC) Website

    Artificial Spin Ice - A New Playground to Better Understand Magnetism Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding...

  13. antarctic sea ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AD of transient model simulations and a new type of sen- sitivity experiments with artificial sea ice growth Born, Andreas 327 Sedimentation and particle dynamics in the...

  14. arctic sea ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AD of transient model simulations and a new type of sen- sitivity experiments with artificial sea ice growth Born, Andreas 388 Sedimentation and particle dynamics in the...

  15. altimeter sea ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AD of transient model simulations and a new type of sen- sitivity experiments with artificial sea ice growth Born, Andreas 218 Sedimentation and particle dynamics in the...

  16. artic sea ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AD of transient model simulations and a new type of sen- sitivity experiments with artificial sea ice growth Born, Andreas 214 Sedimentation and particle dynamics in the...

  17. arctic ice dynamics: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    W. F. Vincent (2008), Seasonal dynamics of bacterial Vincent, Warwick F. 168 Dynamics of artificial spin ice: a continuous honeycomb network MIT - DSpace Summary: We model the...

  18. arctic ice islands: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    analogous to the effects of the Arctic region; KEYWORDS: Arctic Ocean, ice rafting, climate change Citation: Darby, D. A., and J. F. Bischof (2004), A Holocene record of...

  19. Reducing uncertainty in high-resolution sea ice models.

    SciTech Connect (OSTI)

    Peterson, Kara J.; Bochev, Pavel Blagoveston

    2013-07-01T23:59:59.000Z

    Arctic sea ice is an important component of the global climate system, reflecting a significant amount of solar radiation, insulating the ocean from the atmosphere and influencing ocean circulation by modifying the salinity of the upper ocean. The thickness and extent of Arctic sea ice have shown a significant decline in recent decades with implications for global climate as well as regional geopolitics. Increasing interest in exploration as well as climate feedback effects make predictive mathematical modeling of sea ice a task of tremendous practical import. Satellite data obtained over the last few decades have provided a wealth of information on sea ice motion and deformation. The data clearly show that ice deformation is focused along narrow linear features and this type of deformation is not well-represented in existing models. To improve sea ice dynamics we have incorporated an anisotropic rheology into the Los Alamos National Laboratory global sea ice model, CICE. Sensitivity analyses were performed using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA) to determine the impact of material parameters on sea ice response functions. Two material strength parameters that exhibited the most significant impact on responses were further analyzed to evaluate their influence on quantitative comparisons between model output and data. The sensitivity analysis along with ten year model runs indicate that while the anisotropic rheology provides some benefit in velocity predictions, additional improvements are required to make this material model a viable alternative for global sea ice simulations.

  20. Journal of Crystal Growth ] (

    E-Print Network [OSTI]

    ) at high pressure of CO2 (initial PCO2 Ľ 55 bar) and moderate to high temperature (30 and 90 1C) was used and the dissolved quantity of CO2 have a significant effect on the average particle size, specific surface areaJournal of Crystal Growth ] (

  1. Silicon crystal growing by oscillating crucible technique

    DOE Patents [OSTI]

    Schwuttke, G.H.; Kim, K.M.; Smetana, P.

    1983-08-03T23:59:59.000Z

    A process for growing silicon crystals from a molten melt comprising oscillating the container during crystal growth is disclosed.

  2. About International Cruise & Excursions International Cruise & Excursions, Inc. (ICE) is a worldwide travel and

    E-Print Network [OSTI]

    Fisher, Kathleen

    About International Cruise & Excursions International Cruise & Excursions, Inc. (ICE corporations, resorts, cruise lines and leisure travel providers. ICE provides cruise and travel programs-commerce platform, state of the art call centers and customer service and fulfillment operations. Situation ICE

  3. Web-Ice: Integrated Data Collection and Analysis for Macromolecular Crystallography

    E-Print Network [OSTI]

    Gonzalez, Ana

    2008-01-01T23:59:59.000Z

    results. A summary list is also available in Blu-Ice.Figure 7: SSRL Web-Ice interface displaying the summarizedTable 1: Programs used by Web-Ice for data analysis. Program

  4. The influence of subglacial hydrology on the flow of West Antarctic ice streams

    E-Print Network [OSTI]

    Baker, Narelle Paula Marie

    2012-04-10T23:59:59.000Z

    Subglacial hydrology is known to influence the flow of ice. However, difficulty in accessing the base of large ice sheets has made determining the interaction between ice streams, basal sediment and water difficult to discern. The aim of this thesis...

  5. Incorporation of particulates into accreted ice above subglacial Vostok lake, Antarctica 

    E-Print Network [OSTI]

    Siegert, M. J.; Royston-Bishop, G.; Priscu, J. C.; Tranter, M.; Christner, B.; Lee, V.

    2005-01-01T23:59:59.000Z

    The nature of microscopic particulates in meteoric and accreted ice from the Vostok (Antarctica) ice core is assessed in conjunction with existing ice-core data to investigate the mechanism by which particulates are ...

  6. APPROVED ICE STORAGE AIR CONDITIONERS Revised as of 06-18-2008

    E-Print Network [OSTI]

    APPROVED ICE STORAGE AIR CONDITIONERS Revised as of 06-18-2008 The following vendors and their ice storage air conditioners models can be used in the ice storage air conditioner compliance option. Input

  7. Ice stream basal conditions from block-wise surface data inversion and simple regression models of ice stream flow: Application to

    E-Print Network [OSTI]

    Boyce, C. Kevin

    Ice stream basal conditions from block-wise surface data inversion and simple regression models of ice stream flow: Application to Bindschadler Ice Stream O. V. Sergienko,1 R. A. Bindschadler,2 P. L; published 4 December 2008. [1] Widespread basal conditions controlling ice stream flows are still beyond

  8. Ice in the Environment: Proceedings of the 16th IAHR International Symposium on Ice Dunedin, New Zealand, 2nd6th December 2002

    E-Print Network [OSTI]

    Feltham, Daniel

    Ice in the Environment: Proceedings of the 16th IAHR International Symposium on Ice Dunedin, New OF DETERMINING A GEOPHYSICAL-SCALE SEA ICE RHEOLOGY FROM LABORATORY EXPERIMENTS Daniel Feltham1 and Peter Sammonds2 and Daniel Hatton2 ABSTRACT We present a methodology that allows a sea ice rheology, suitable

  9. ICE IGERT Mission The mission of the ICE IGERT program is to exploit the synergistic interface between engineering and the life sciences to enable

    E-Print Network [OSTI]

    Mountziaris, T. J.

    1 ICE IGERT Mission The mission of the ICE IGERT program is to exploit the synergistic interface foundation for future interdisciplinary research success. ICE IGERT Curriculum Structure (minimum of 19 credits) ICE IGERT promotes broad-based graduate training in cellular engineering through the following

  10. Modeling the evolution of polar ice sheets: Ice sheet system model workshop; Bergen, Norway, 2-4 June 2014

    E-Print Network [OSTI]

    Larour, E; Schlegel, N; Morlighem, M

    2014-01-01T23:59:59.000Z

    Model Workshop; Bergen, Norway, 2?4 June 2014 The Ice SheetUniversity of Bergen in Norway, in June 2014. This is the

  11. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/, Frazil Deposition Under Growing Sea Ice

    E-Print Network [OSTI]

    McGuinness, Mark

    Ice M.J. McGuinness,1,4 M.J.M. Williams,2 P.J. Langhorne,3 C. Purdie,3 J. Crook4 Abstract. Platelet ice may be an important component of Antarctic land-fast sea ice. Typically, it is found at depth in first-year landfast sea ice cover, near ice shelves. To explain why platelet ice is not commonly

  12. Hyper Space Complex Number

    E-Print Network [OSTI]

    Shanguang Tan

    2007-04-23T23:59:59.000Z

    A new kind of numbers called Hyper Space Complex Numbers and its algebras are defined and proved. It is with good properties as the classic Complex Numbers, such as expressed in coordinates, triangular and exponent forms and following the associative and commutative laws of addition and multiplication. So the classic Complex Number is developed from in complex plane with two dimensions to in complex space with N dimensions and the number system is enlarged also.

  13. Freeze crystallization technology for Kraft black liquor concentration. Third report

    SciTech Connect (OSTI)

    Johnson, W.E.; Rhodes, C.R.

    1985-04-01T23:59:59.000Z

    About 25% of the purchased energy in the pulp and paper industry is used to concentrate black liquor. The technical feasibility of using freeze concentration to supplement evaporation has been successfully demonstrated, and results indicate that energy consumption can be reduced 45%. After compiling a considerable data base on the characteristics of black liquor at low temperature and after developing a computer program to aid analysis, the process chosen was vacuum freezing-vapor absorption (VFVA). A pilot plant was built and operated; however, due to problems with crystallization of the absorbent and contamination, it was found that maintaining the conditions necessary for a continuous process was not practical at the present state of development. Therefore, indirect freezing was used for all subsequent work. This required the design and fabrication of a simple shuttle crystallizer to replace scraped surface units conventionally used. CSI also developed an integrated ice separation column that combined crystal growth, a concentration gradient, and washing all in one unit. Finally, extensive heat transfer coefficient data were collected so that a preliminary design could be completed for a 350 TPD industrial freeze concentration unit. An economic analysis was calculated in order to compare using evaporation and freeze concentration to process the increased liquor flow from a pulp mill expansion. A 200,000 lb/hr freezing unit used to preconcentrate the mill's entire stream up to 18.7% solids would save $10 to $16 per ton of pulp.

  14. IceCube Project Monthly Report Accomplishments

    E-Print Network [OSTI]

    Saffman, Mark

    is the culmination of a series of ICECUBE - TOTAL US and NON-US 20.8% 19.4% 17.6% 6.6% 20.4% 19.0% 16.9% 6.6% 0.0% 10.0% 20.0% 30.0% 40.0% 50.0% 60.0% 70.0% 80.0% 90.0% 100.0% 3FY02-2FY03 3FY03-2FY04 A-04 M -04 J-04 J-04 A and Safety ­ This month the IceCube Safety and Quality Assurance Manager participated in site visits

  15. Climate, Ocean and Sea Ice Modeling (COSIM)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccessAlamosCharacterization2Climate, Ocean and Sea Ice Modeling

  16. ARM - Lesson Plans: When Land Ice Melts

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow, AlaskaWhen Floating Ice Melts in the SeaWhen

  17. Developing and Evaluating Ice Cloud Parameterizations by

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign: Potential Application toDevelopingand Evaluating Ice Cloud

  18. Hydration of the lower stratosphere by ice crystal geysers over land convective systems

    E-Print Network [OSTI]

    Khaykin, S.

    The possible impact of deep convective overshooting over land has been explored by six simultaneous soundings of water vapour, particles and ozone in the lower stratosphere next to Mesoscale Convective Systems (MCSs) during ...

  19. Microsoft PowerPoint - 6_Zhao_ice crystals.ppt

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighand Retrievals fromprocess usedGELustre FileBimodal Particle

  20. Passive ice freezing-releasing heat pipe. [Patent application

    DOE Patents [OSTI]

    Gorski, A.J.; Schertz, W.W.

    1980-09-29T23:59:59.000Z

    A heat pipe device has been developed which permits completely passive ice formation and periodic release of ice without requiring the ambient temperature to rise above the melting point of water. This passive design enables the maximum amount of cooling capacity to be stored in the tank.

  1. Dynamical mechanism of antifreeze proteins to prevent ice growth

    E-Print Network [OSTI]

    B. Kutschan; K. Morawetz; S. Thoms

    2014-07-24T23:59:59.000Z

    The fascinating ability of algae, insects and fishes to survive at temperatures below normal freezing is realized by antifreeze proteins (AFPs). These are surface-active molecules and interact with the diffusive water/ice interface thus preventing complete solidification. We propose a new dynamical mechanism on how these proteins inhibit the freezing of water. We apply a Ginzburg-Landau type approach to describe the phase separation in the two-component system (ice, AFP). The free energy density involves two fields: one for the ice phase with a low AFP concentration, and one for liquid water with a high AFP concentration. The time evolution of the ice reveals microstructures resulting from phase separation in the presence of AFPs. We observed a faster clustering of pre-ice structure connected to a locking of grain size by the action of AFP, which is an essentially dynamical process. The adsorption of additional water molecules is inhibited and the further growth of ice grains stopped. The interfacial energy between ice and water is lowered allowing the AFPs to form smaller critical ice nuclei. Similar to a hysteresis in magnetic materials we observe a thermodynamic hysteresis leading to a nonlinear density dependence of the freezing point depression in agreement with the experiments.

  2. How Do Cultural Differences Affect Utilization of the ICE Approach?

    E-Print Network [OSTI]

    de Weck, Olivier L.

    with permission. Abstract. Integrated Concurrent Engineering (ICE) is a design approach initially developed process: "Integrated Concurrent Engineering (ICE) is a real-time collaborative process in which-understood procedures for real-time collaboration; concurrent quantitative engineering and qualitative conversation. 4

  3. ENERGY BASED ICE COLLISION FORCES Claude Daley1

    E-Print Network [OSTI]

    Daley, Claude

    1 ENERGY BASED ICE COLLISION FORCES Claude Daley1 1 Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1C 3X5 ABSTRACT Ice collision forces can be determined by energy considerations. A variety of interaction geometry cases are considered. The indentation energy functions for eight different

  4. ENERGY BASED ICE COLLISION FORCES Claude Daley1

    E-Print Network [OSTI]

    Daley, Claude

    ENERGY BASED ICE COLLISION FORCES Claude Daley1 1 Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1C 3X5 ABSTRACT Ice collision forces can be determined by energy considerations. A variety of interaction geometry cases are considered. The indentation energy functions for eight different

  5. UV Irradiation of Polycyclic Aromatic Hydrocarbons in Ices

    E-Print Network [OSTI]

    . Clemett,3 Richard N. Zare3 Polycyclic aromatic hydrocarbons (PAHs) in water ice were exposed to ultra meteorites. Hydrogen and deu- terium atoms exchange readily between the PAHs and the ice, which may explain abundant and widespread class of carbon-car- rying gaseous species is believed to be PAHs (3­5). In dense

  6. Ice Storm Damage Greater Along the Terrestrial-Aquatic Interface

    E-Print Network [OSTI]

    Kraft, Clifford E.

    Ice Storm Damage Greater Along the Terrestrial-Aquatic Interface in Forested Landscapes Andrew A- tems. In 1998, a severe ice storm damaged over ten million hectares of forest across northern New York investigated the spatial arrangement of forest damage at the terrestrial-aquatic interface, an ecological edge

  7. IceCube Project Monthly Report November 2007

    E-Print Network [OSTI]

    Saffman, Mark

    the current budgets or the budgets modified by the cost performance index. Change Log - IceCube Total Project IceCube array with a detector uptime of 97%, above the internal monthly goal of 95%. #12;Cost design, development, procured materials, and the construction of the infrastructure that supports

  8. Azimuth Variation in Microwave Backscatter over the Greenland Ice Sheet

    E-Print Network [OSTI]

    Long, David G.

    Azimuth Variation in Microwave Backscatter over the Greenland Ice Sheet Ivan S. Ashcraft and David backscatter measurements are becoming an important tool for monitoring the dynamic behavior of the Greenland ice sheet. However, most Greenland studies assume constant backscatter for varying azimuth angles

  9. Arctic catastrophes in an idealized sea ice model Ian Eisenman

    E-Print Network [OSTI]

    Eisenman, Ian

    thermodynamics, varying open water fraction, an energy balance atmosphere, and scalable CO2. We find that summer.e., reflectiveness) between sea ice and the open water that is exposed when it melts. Bare or snow-covered sea ice reflects most sunlight back to space, while the dark ocean surface absorbs most incident light. Global

  10. Optimization of Ice Thermal Storage Systems Design for HVAC Systems

    E-Print Network [OSTI]

    Nassif, N.; Hall, C.; Freelnad, D.

    2013-01-01T23:59:59.000Z

    Ice thermal storage is promising technology to reduce energy costs by shifting the cooling cost from on-peak to off-peak periods. The paper discusses the optimal design of ice thermal storage and its impact on energy consumption, demand, and total...

  11. CO diffusion into amorphous H2O ices

    E-Print Network [OSTI]

    Lauck, Trish; Shulenberger, Katherine; Rajappan, Mahesh; Oberg, Karin I; Cuppen, Herma M

    2015-01-01T23:59:59.000Z

    The mobility of atoms, molecules and radicals in icy grain mantles regulate ice restructuring, desorption, and chemistry in astrophysical environments. Interstellar ices are dominated by H2O, and diffusion on external and internal (pore) surfaces of H2O-rich ices is therefore a key process to constrain. This study aims to quantify the diffusion kinetics and barrier of the abundant ice constituent CO into H2O dominated ices at low temperatures (15-23 K), by measuring the mixing rate of initially layered H2O(:CO2)/CO ices. The mixed fraction of CO as a function of time is determined by monitoring the shape of the infrared CO stretching band. Mixing is observed at all investigated temperatures on minute time scales, and can be ascribed to CO diffusion in H2O ice pores. The diffusion coefficient and final mixed fraction depend on ice temperature, porosity, thickness and composition. The experiments are analyzed by applying Fick's diffusion equation under the assumption that mixing is due to CO diffusion into an i...

  12. IceCube Project Monthly Report -June 2010 Accomplishments

    E-Print Network [OSTI]

    Saffman, Mark

    (April 29-30) and an ice drilling technology meeting (April 27-28). Cost and Schedule Performance Service Corporation and New York Air National Guard FY10 on-ice fuel and labor cost savings. Contingency. $125K WBS 1.2 Implementation Additional UW & PSL Labor to replace and refurbish drill hardware. On

  13. absorption scale ice: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    absorption scale ice First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Optical properties of deep ice at...

  14. An Assessment of Lattice Energy Minimization for the Prediction of Molecular Organic Crystal Structures

    E-Print Network [OSTI]

    de Gispert, Adriŕ

    An Assessment of Lattice Energy Minimization for the Prediction of Molecular Organic Crystal Received August 18, 2004 ABSTRACT: Lattice energy searches for theoretical low-energy crystal forms with respect to the global minimum energy structure, and we determine the number of unobserved structures lower

  15. Large single domain 123 material produced by seeding with single crystal rare earth barium copper oxide single crystals

    DOE Patents [OSTI]

    Todt, Volker (Lemont, IL); Miller, Dean J. (Darien, IL); Shi, Donglu (Oak Park, OH); Sengupta, Suvankar (Columbus, OH)

    1998-01-01T23:59:59.000Z

    A method of fabricating bulk YBa.sub.2 Cu.sub.3 O.sub.x where compressed powder oxides and/or carbonates of Y and Ba and Cu present in mole ratios to form YBa.sub.2 Cu.sub.3 O.sub.x are heated in the presence of a Nd.sub.1+x Ba.sub.2-x Cu.sub.3 O.sub.y seed crystal to a temperature sufficient to form a liquid phase in the YBa.sub.2 Cu.sub.3 O.sub.x while maintaining the seed crystal solid. The materials are slowly cooled to provide a YBa.sub.2 Cu.sub.3 O.sub.x material having a predetermined number of domains between 1 and 5. Crack-free single domain materials can be formed using either plate shaped seed crystals or cube shaped seed crystals with a pedestal of preferential orientation material.

  16. Methods and apparatus for rotor blade ice detection

    DOE Patents [OSTI]

    LeMieux, David Lawrence

    2006-08-08T23:59:59.000Z

    A method for detecting ice on a wind turbine having a rotor and one or more rotor blades each having blade roots includes monitoring meteorological conditions relating to icing conditions and monitoring one or more physical characteristics of the wind turbine in operation that vary in accordance with at least one of the mass of the one or more rotor blades or a mass imbalance between the rotor blades. The method also includes using the one or more monitored physical characteristics to determine whether a blade mass anomaly exists, determining whether the monitored meteorological conditions are consistent with blade icing; and signaling an icing-related blade mass anomaly when a blade mass anomaly is determined to exist and the monitored meteorological conditions are determined to be consistent with icing.

  17. Fast-flowing outlet glaciers on Svalbard ice caps

    SciTech Connect (OSTI)

    Dowdeswell, J.A. (Univ. of Cambridge (England)); Collin, R.L. (University College of Wales, Aberystwyth (England))

    1990-08-01T23:59:59.000Z

    Four well-defined outlet glaciers are present on the 2510 km{sup 2} cap of Vestfonna in Nordaustlandet, Svalbard. Airborne radio echo sounding and aerial-photograph and satellite-image analysis methods are used to analyze the morphology and dynamics of the ice cap and its component outlet glaciers. The heavily crevassed outlets form linear depressions in the ice-cap surface and flow an order of magnitude faster than the ridges of uncrevassed ice between them. Ice flow on the ridges is accounted for by internal deformation alone, whereas rates of outlet glacier flow require basal motion. One outlet has recently switched into and out of a faster mode of flow. Rapid terminal advance, a change from longitudinal compression to tension, and thinning in the upper basin indicate surge behavior. Observed outlet glacier discharge is significantly greater than current inputs of mass of the ice cap, indicating that present rates of flow cannot be sustained under the contemporary climate.

  18. Ice emission and the redshifts of submillimeter sources

    E-Print Network [OSTI]

    C. C. Dudley; M. Imanishi; P. R. Maloney

    2008-02-12T23:59:59.000Z

    Observations at submillimeter wavelengths have revealed a population of sources thought to be at relatively large redshifts. The position of the 850 $\\mu$m passband on the Rayleigh-Jeans portion of the Planck function leads to a maximum redshift estimate of $z\\sim$4.5 since sources will not retain their redshift independent brightness close to the peak of the Planck function and thus drop out of surveys. Here we review evidence that ice absorption is present in the spectra of local ultraluminous infrared galaxies which are often taken as analogs for the 850 $\\mu$m source population. We consider the implication of this absorption for ice induced spectral structure at far infrared wavelengths and present marginal astronomical evidence that amorphous ice may have a feature similar to crystalline ice near 150 $\\mu$m. Recent corroborative laboratory evidence is supportive of this conclusion. It is argued that early metal enrichment by pair instability SN may lead to a high ice content relative to refractory dust at high redshift and a fairly robust detection of ice emission in a $z=6.42$ quasar is presented. It is further shown that ice emission is needed to understand the 450 $\\mu$m sources observed in the GOODS-N field. We are thus encouraged to apply far infrared ice emission models to the available observations of HDF 850.1, the brightest submillimeter source in the {\\it Hubble Deep Field}. We suggest that a redshift as large as 13 may need to be considered for this source, nearly a factor of three above the usual top estimate. Inclusion of the possibility of far infrared ice emission in the spectral energy distributions of model sources generally broadens the range of redshifts to be considered for submillimeter sources compared to models without ice emission.

  19. 43rd AIAA Aerospace Sciences Meeting and Exhibit, 10-13 Jan 2005, Reno, Nevada Improved De-icing of an Inclined Windshield Surface

    E-Print Network [OSTI]

    Roy, Subrata

    transfer coefficient, W/m2 K k Thermal conductivity, W/m-K Nu Nusselt number P Static pressure, Pa SL-icing of an Inclined Windshield Surface Haribalan Kumar* and Subrata Roy Computational Plasma Dynamics Laboratory. Nomenclature Cp Specific heat at constant pressure, kJ/kg-K E Specific enthalpy, kJ/kg H Convection heat

  20. SnapShot: Visualization to Propel Ice Hockey Analytics Hannah Pileggi, Charles D. Stolper, J. Michael Boyle, and John T. Stasko, Senior Member, IEEE

    E-Print Network [OSTI]

    Stasko, John T.

    SnapShot: Visualization to Propel Ice Hockey Analytics Hannah Pileggi, Charles D. Stolper, J A of eight radial heat maps displaying patterns of shot lengths at each of the indicated rinks during into tables of numbers, divorced from the rinks, pitches, and courts where they were generated. Currently

  1. D-D Nuclear Fusion Using Different Size Pyroelectric Crystals

    E-Print Network [OSTI]

    Danon, Yaron

    D-D Nuclear Fusion Using Different Size Pyroelectric Crystals A. M. Kovanen, D. J. Gillich, T. Z of Homeland Security under cooperative agreement number 2007-DN-077-ER0003. The authors are with the Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY. A. M

  2. Improvements in Representations of Cloud Microphysics for BBHRP and Models using Data Collected during M-PACE and TWP-ICE

    SciTech Connect (OSTI)

    Greg M. McFarquhar

    2010-02-22T23:59:59.000Z

    In our research we proposed to use data collected during the 2004 Mixed-Phase Arctic Cloud Experiment (MPACE) and the 2006 Tropical Warm Pool International Cloud Experiment (TWP-ICE) to improve retrievals of ice and mixed-phase clouds, to improve our understanding of how cloud and radiative processes affect cloud life cycles, and to develop and test methods for using ARM data more effectively in model. In particular, we proposed to: 1) use MPACE in-situ data to determine how liquid water fraction and cloud ice and liquid effective radius (r{sub ei} and r{sub ew}) vary with temperature, normalized cloud altitude and other variables for Arctic mixed-phase clouds, and to use these data to evaluate the performance of model parameterization schemes and remote sensing retrieval algorithms; 2) calculate rei and size/shape distributions using TWP-ICE in-situ data, investigate their dependence on cirrus type (oceanic or continental anvils or cirrus not directly traced to convection), and develop and test representations for MICROBASE; 3) conduct fundamental research enhancing our understanding of cloud/radiative interactions, concentrating on effects of small crystals and particle shapes and sizes on radiation; and 4) improve representations of microphysical processes for models (fall-out, effective density, mean scattering properties, rei and rew) and provide them to ARM PIs. In the course of our research, we made substantial progress on all four goals.

  3. Demixing cascades in cluster crystals

    E-Print Network [OSTI]

    Nigel B. Wilding; Peter Sollich

    2014-07-14T23:59:59.000Z

    In a cluster crystal, each lattice site is occupied by multiple soft-core particles. As the number density is increased at zero temperature, a `cascade' of isostructural phase transitions can occur between states whose site occupancy differs by unity. For low but finite temperature, each of these transitions terminates in a critical point. Using tailored Monte Carlo simulation techniques we have studied such demixing cascades in systems of soft particles interacting via potentials of the generalized exponential form $u(r)=\\epsilon\\exp[-(r/\\sigma)^n]$. We have estimated the critical parameters of the first few transitions in the cascade as a function of the softness parameter $n$. The critical temperature and pressure exhibit non-monotonic behaviour as $n$ is varied, although the critical chemical potential remains monotonic. The trends for the pressure and chemical potential are confirmed by cell model calculations at zero temperature. As $n\\to 2^+$, all the transitions that we have observed are preempted by melting although we cannot rule out that clustering transitions survive at high density.

  4. New organic crystals for pulse shape discrimination

    SciTech Connect (OSTI)

    Hull, G; Zaitseva, N; Cherepy, N; Newby, J; Stoeffl, W; Payne, S

    2008-07-16T23:59:59.000Z

    Efficient, readily-available, low-cost, high-energy neutron detectors can play a central role in detecting illicit nuclear weapons since neutrons are a strong indication for the presence of fissile material such as Plutonium and Highly-Enriched Uranium. The main challenge in detecting fast neutrons consists in the discrimination of the signal from the gamma radiation background. At present, the only well-investigated organic crystal scintillator for fast neutron detection, in a n/{gamma} mixed field, is stilbene, which while offering good pulse shape discrimination, is not widely used because of its limited availability and high cost. In this work we report the results of our studies made with a number of new organic crystals, which exhibit pulse shape discrimination for detection of fast neutrons. In particular 1,1,4,4-tetraphenyl-1,3-butadiene features a light yield higher than anthracene and a Figure of Merit (FOM) for the pulse shape discrimination better than stilbene. New crystals are good candidates for the low-cost solution growth method, thus representing promising organic scintillators for widespread deployment for high-energy neutron detection.

  5. Crystal face temperature determination means

    DOE Patents [OSTI]

    Nason, D.O.; Burger, A.

    1994-11-22T23:59:59.000Z

    An optically transparent furnace having a detection apparatus with a pedestal enclosed in an evacuated ampule for growing a crystal thereon is disclosed. Temperature differential is provided by a source heater, a base heater and a cold finger such that material migrates from a polycrystalline source material to grow the crystal. A quartz halogen lamp projects a collimated beam onto the crystal and a reflected beam is analyzed by a double monochromator and photomultiplier detection spectrometer and the detected peak position in the reflected energy spectrum of the reflected beam is interpreted to determine surface temperature of the crystal. 3 figs.

  6. Florida Nuclear Profile - Crystal River

    U.S. Energy Information Administration (EIA) Indexed Site

    Crystal River1" "Unit","Summer capacity (mw)","Net generation (thousand mwh)","Summer capacity factor (percent)","Type","Commercial operation date","License expiration date"...

  7. Air conditioning system with supplemental ice storing and cooling capacity

    DOE Patents [OSTI]

    Weng, Kuo-Lianq (Taichung, TW); Weng, Kuo-Liang (Taichung, TW)

    1998-01-01T23:59:59.000Z

    The present air conditioning system with ice storing and cooling capacity can generate and store ice in its pipe assembly or in an ice storage tank particularly equipped for the system, depending on the type of the air conditioning system. The system is characterized in particular in that ice can be produced and stored in the air conditioning system whereby the time of supplying cooled air can be effectively extended with the merit that the operation cycle of the on and off of the compressor can be prolonged, extending the operation lifespan of the compressor in one aspect. In another aspect, ice production and storage in great amount can be performed in an off-peak period of the electrical power consumption and the stored ice can be utilized in the peak period of the power consumption so as to provide supplemental cooling capacity for the compressor of the air conditioning system whereby the shift of peak and off-peak power consumption can be effected with ease. The present air conditioning system can lower the installation expense for an ice-storing air conditioning system and can also be applied to an old conventional air conditioning system.

  8. GRAPH-BASED METHOD FOR MULTITEMPORAL SEGMENTATION OF SEA ICE FLOES FROM SATELLITE DATA

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    the Arc- tic sea ice pack in December 2007, continuously moved with the Arctic ocean currents and meltedGRAPH-BASED METHOD FOR MULTITEMPORAL SEGMENTATION OF SEA ICE FLOES FROM SATELLITE DATA Claudio, MODIS, Sea Ice Floes. ABSTRACT: Automated segmentation of the sea ice evolution would allow scientists

  9. Arctic Ice Dynamics Joint Experiment (AIDJEX) assumptions revisited and found inadequate

    E-Print Network [OSTI]

    Sulsky, Deborah L.

    the Arctic Ice Dynamics Joint Experiment (AIDJEX) assumptions about pack ice behavior with an eye to modeling the behavior of pack ice. A model based on these assumptions is needed to represent the deformation and stress in pack ice on scales from 10 to 100 km, and would need to explicitly resolve discontinuities

  10. Effect of air-sea-ice interaction on winter 1996 Southern Ocean subpolar storm distribution

    E-Print Network [OSTI]

    Columbia University

    is the baroclinic instability caused by the cold air blown from the ice pack to the warm open-ocean waters. Where with the entire pack ice/open-water region. The heat flux changes considerably in the area from continental ice to pack ice, resulting in strong baroclinicity that leads to the enhanced development of vortices. Streten

  11. Gas ageice age differences and the chronology of the Vostok ice core, M. L. Bender,1

    E-Print Network [OSTI]

    Chappellaz, Jérôme

    Gas age­ice age differences and the chronology of the Vostok ice core, 0­100 ka M. L. Bender,1 G. [1] Gas is trapped in polar ice at depths of $50­120 m and is therefore significantly younger than cores (Vostok, Dome Fuji, and Dome C). We recorrelate the gas records of Vostok and Greenland Ice Sheet

  12. IDENTIFYING ICE HYDROMETEOR SIGNATURES ABOVE SUMMIT, GREENLAND USING A MULTI-INSTRUMENT APPROACH

    E-Print Network [OSTI]

    Wisconsin at Madison, University of

    IDENTIFYING ICE HYDROMETEOR SIGNATURES ABOVE SUMMIT, GREENLAND USING A MULTI. These retrievals, however, may be adversely affected by ice hydrometeors commonly observed in mixed phase clouds. Research on the effect of ice hydrometeors on the microwave signal is insufficient. We establish that ice

  13. Adaptive mesh, finite volume modeling of marine ice sheets Stephen L. Cornforda

    E-Print Network [OSTI]

    Adaptive mesh, finite volume modeling of marine ice sheets Stephen L. Cornforda , Daniel F. Martinb Abstract Continental scale marine ice sheets such as the present day West Antarctic Ice Sheet are strongly phenomenon of this kind is the migration of the grounding line -- the division between ice in contact

  14. Sessions 1526 & 2526 The URI Integrated Computer Engineering Design (ICED) Curriculum

    E-Print Network [OSTI]

    Uht, Augustus K.

    Sessions 1526 & 2526 The URI Integrated Computer Engineering Design (ICED) Curriculum: Progress the ICED curriculum in the Fall of 1997. The key feature of ICED is a substantial 2-3 year long project of ICED after two years of startup operation. Some custom hardware was required for the curriculum

  15. IMPLICATIONS OF CO, GLOBAL WARMING O N GREAT LAKES ICE COVER

    E-Print Network [OSTI]

    IMPLICATIONS OF CO, GLOBAL WARMING O N GREAT LAKES ICE COVER RAYMOND A. ASSEL US. Department to project daily mean basin ice cover and annual ice cover duration for Lakes Superior and Erie. Models were), and the Oregon State University (OSU)general circulationmodels. Ice cover estimateswere made for the West

  16. Ice-associated phytoplankton blooms in the southeastern Bering Sea Meibing Jin,1

    E-Print Network [OSTI]

    Ice-associated phytoplankton blooms in the southeastern Bering Sea Meibing Jin,1 Clara Deal,1 Jia 2007. [1] Ice-associated phytoplankton blooms in the south- eastern Bering Sea can critically impact ice algal components, our 1-D ecosystem model successfully reproduced the observed ice

  17. ESTIMATING BEDROCK AND SURFACE LAYER BOUNDARIES AND CONFIDENCE INTERVALS IN ICE SHEET RADAR IMAGERY USING MCMC

    E-Print Network [OSTI]

    Menczer, Filippo

    ESTIMATING BEDROCK AND SURFACE LAYER BOUNDARIES AND CONFIDENCE INTERVALS IN ICE SHEET RADAR IMAGERY and Computing Indiana University Bloomington, Indiana USA ABSTRACT Climate models that predict polar ice sheet behavior require accurate measurements of the bedrock-ice and ice-air bound- aries in ground

  18. Ice sheets and their dynamics Continuum thermo-mechanical model of a glacier

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Ice sheets and their dynamics Continuum thermo-mechanical model of a glacier Shallow Ice Approximation (SIA) SIA-I Iterative Improvement Technique Benchmarks Numerical modeling of ice-sheet dynamics and Cartography, Zdiby 1.6.2010 Ondej Soucek Ph.D. defense #12;Ice sheets and their dynamics Continuum thermo

  19. Ice-assisted electron beam lithography of graphene Jules A Gardener1

    E-Print Network [OSTI]

    1 Ice-assisted electron beam lithography of graphene Jules A Gardener1 and Jene A Golovchenko1 with a thin ice layer. The irradiated ice plays a crucial role in the process by providing activated species that locally remove graphene from a silicon dioxide substrate. After patterning the graphene, the ice resist

  20. Pleistocene ice and paleo-strain rates at Taylor Glacier, Antarctica S.M. Aciego a

    E-Print Network [OSTI]

    Severinghaus, Jeffrey P.

    Pleistocene ice and paleo-strain rates at Taylor Glacier, Antarctica S.M. Aciego a , K.M. Cuffey b September 2006 Abstract Ice exposed in ablation zones of ice sheets can be a valuable source of samples for paleoclimate studies and information about long-term ice dynamics. We report a 28-km long stable isotope

  1. Ice Climbing in Clear Creek Canyon A climbing trip report by Glenn Murray

    E-Print Network [OSTI]

    Ice Climbing in Clear Creek Canyon A climbing trip report by Glenn Murray SUMMARY: I climb ice in to ask about local climbing. The guys there told me there was ice nearby, in Clear Creek Canyon. I. Four pitches? Five? It was time to find a partner. The only ice climber I knew in Denver was a friend

  2. Snow and Ice Control Best Management Practices Parking Lots, Sidewalks, Roads

    E-Print Network [OSTI]

    Minnesota, University of

    Snow and Ice Control Best Management Practices Parking Lots, Sidewalks, Roads Minnesota Circuit opportunity to improve the way we manage snow and ice in Minnesota. By using snow and ice control best safer--while saving money and protecting water quality. Current Situation The snow and ice maintenance

  3. SEA ICE MAPPING ALGORITHM FOR QUIKSCAT AND SEAWINDS Quinn P. Remund and David G. Long

    E-Print Network [OSTI]

    Long, David G.

    SEA ICE MAPPING ALGORITHM FOR QUIKSCAT AND SEAWINDS Quinn P. Remund and David G. Long Brigham Young@ee.byu.edu Abstruct- Polar sea ice extent is an important input to global climate models and is considered are sensitive to the pres- ence of sea ice. An algorithm has been developed for sea ice extent detection using

  4. The ice flow behavior in the neighborhood of the grounding line. Non-Newtonian case.

    E-Print Network [OSTI]

    Fontelos, Marco

    The ice flow behavior in the neighborhood of the grounding line. Non-Newtonian case. Marco A line dynamics. The grounding line is the line where tran- sition between ice attached to the solid ground and ice floating over the sea takes place. We analyze a mathematical model describing the ice flow

  5. Instruments and Methods Intermediate-depth ice coring of high-altitude and polar glaciers

    E-Print Network [OSTI]

    Howat, Ian M.

    an electromechanical drill (EMD) and an ethanol thermal electric drill (ETED). The EMD permitted an average ice in cold and temperate ice and in clean and particle-laden ice. The influence of the ethanol drilling fluid- arctica, 2000) and an ethanol thermal electric drill (ETED; Zagorodnov and others, 1998)). Ice thicknesses

  6. Recent ice loss from the Fleming and other glaciers, Wordie Bay, West Antarctic Peninsula

    E-Print Network [OSTI]

    Kansas, University of

    that the glaciers accelerated following ice shelf removal, and have been thinning and losing mass to the ocean overRecent ice loss from the Fleming and other glaciers, Wordie Bay, West Antarctic Peninsula E. Rignot ice thickness data from 2002, reveal that the glaciers flowing into former Wordie Ice Shelf, West

  7. Development, sensitivity analysis, and uncertainty quantification of high-fidelity arctic sea ice models.

    SciTech Connect (OSTI)

    Peterson, Kara J.; Bochev, Pavel Blagoveston; Paskaleva, Biliana S.

    2010-09-01T23:59:59.000Z

    Arctic sea ice is an important component of the global climate system and due to feedback effects the Arctic ice cover is changing rapidly. Predictive mathematical models are of paramount importance for accurate estimates of the future ice trajectory. However, the sea ice components of Global Climate Models (GCMs) vary significantly in their prediction of the future state of Arctic sea ice and have generally underestimated the rate of decline in minimum sea ice extent seen over the past thirty years. One of the contributing factors to this variability is the sensitivity of the sea ice to model physical parameters. A new sea ice model that has the potential to improve sea ice predictions incorporates an anisotropic elastic-decohesive rheology and dynamics solved using the material-point method (MPM), which combines Lagrangian particles for advection with a background grid for gradient computations. We evaluate the variability of the Los Alamos National Laboratory CICE code and the MPM sea ice code for a single year simulation of the Arctic basin using consistent ocean and atmospheric forcing. Sensitivities of ice volume, ice area, ice extent, root mean square (RMS) ice speed, central Arctic ice thickness, and central Arctic ice speed with respect to ten different dynamic and thermodynamic parameters are evaluated both individually and in combination using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA). We find similar responses for the two codes and some interesting seasonal variability in the strength of the parameters on the solution.

  8. Using Satellite Radar Data to Map and Monitor Variations in Great Lakes Ice Cover

    E-Print Network [OSTI]

    , for image-to-image classification, a library of backscatter signatures of different ice types is needed) classification technique has shown that different ice types in the ice cover can be identified and mapped for use with calibrated SAR imagery. III. SAR ICE CLASSIFICATION AND MAPPING During the 1997 winter season

  9. Elastic uplift in southeast Greenland due to rapid ice mass loss Shfaqat A. Khan,1

    E-Print Network [OSTI]

    Larson, Kristine

    Elastic uplift in southeast Greenland due to rapid ice mass loss Shfaqat A. Khan,1 John Wahr,2] The rapid unloading of ice from the southeastern sector of the Greenland ice sheet between 2001 and 2006), Elastic uplift in southeast Greenland due to rapid ice mass loss, Geophys. Res. Lett., 34, L21701, doi:10

  10. Experimental Validation of a Computational Fluid Dynamics Model for IAQ applications in Ice Rink Arenas

    E-Print Network [OSTI]

    Chen, Qingyan "Yan"

    1 Experimental Validation of a Computational Fluid Dynamics Model for IAQ applications in Ice Rink, USA, Fax: 617-432-4122, Abstract Many ice rink arenas have ice resurfacing equipment that uses fossil temperature distributions in ice rinks. The numerical results agree reasonably with the corresponding

  11. NAO influence on net sea ice production and exchanges in the Arctic region: a numerical study

    E-Print Network [OSTI]

    Hu, Aixue

    NAO influence on net sea ice production and exchanges in the Arctic region: a numerical study Aixue The variability of net sea ice production and sea ice exchange between the Arctic and its adjacent seas export) is the major factor controlling the net sea ice production in the Arctic region since a thinning

  12. NAO influence on net sea ice production and exchanges in the Arctic region

    E-Print Network [OSTI]

    Hu, Aixue

    NAO influence on net sea ice production and exchanges in the Arctic region Aixue Hu, Claes Rooth and Rainer Bleck February 18, 2003 Abstract The variability of the net sea ice production and the sea ice circulation model. The wind driven divergence (or ice flux export) is the major factor controlling the net sea

  13. Developing a coupled ice flow, meltwater plume model to study Developing a coupled ice flow, meltwater plume model to study interactions beneath ice shelves off the coast of West Antarctica.interactions beneath ice shelves off the coast of West Antarctica

    E-Print Network [OSTI]

    , meltwater plume model to study interactions beneath ice shelves off the coast of West Antarctica.interactions beneath ice shelves off the coast of West Antarctica. Victoria Lee1 (v.lee@bristol.ac.uk), Tony Payne1 on the Antarctic Ice Sheet. Observational studies have shown that ice shelves off the coast of West Antarctica

  14. Transoceanic infragravity waves impacting Antarctic ice shelves Peter D. Bromirski,1

    E-Print Network [OSTI]

    Boyce, C. Kevin

    Transoceanic infragravity waves impacting Antarctic ice shelves Peter D. Bromirski,1 Olga V that IG- wave forcing may produce ice-shelf fractures that enable abrupt disintegration of ice shelves impacting Antarctic ice shelves, Geophys. Res. Lett., 37, L02502, doi:10.1029/2009GL041488. 1. Introduction

  15. THE SHRINKING ARCTIC ICE CAP From the IPCC* Summary For Policymakers...

    E-Print Network [OSTI]

    THE SHRINKING ARCTIC ICE CAP From the IPCC* Summary For Policymakers... "Sea ice is projected] - a phenomenon sometimes referred to as "Arctic amplification". As Arctic temperatures rise, sea ice melts for the 20th century. The rate at which the modeled 21st century Arctic warming and sea ice melting occurs

  16. Multiple effects of ice load changes and associated stress change on magmatic systems

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    . Pressure release melting due to ice cap retreat in Iceland may at present times generate a similar amount that part of this magma may be captured in the crust, rather than being erupted. Gradual retreat of ice caps retreat of ice caps and glaciers worldwide; many of which are located in volcanic regions. The reduced ice

  17. Relationships between Arctic Sea Ice and Clouds during Autumn AXEL J. SCHWEIGER AND RON W. LINDSAY

    E-Print Network [OSTI]

    Francis, Jennifer

    , as the direct radiative effects of cloud cover changes are compensated for by changes in the temperature The connection between sea ice variability and cloud cover over the Arctic seas during autumn is investigated that cloud cover variability near the sea ice margins is strongly linked to sea ice variability. Sea ice

  18. Photodesorption of ices I: CO, N2 and CO2

    E-Print Network [OSTI]

    Karin I. Oberg; Ewine F. van Dishoeck; Harold Linnartz

    2009-01-23T23:59:59.000Z

    A longstanding problem in astrochemistry is how molecules can be maintained in the gas phase in dense inter- and circumstellar regions. Photodesorption is a non-thermal desorption mechanism, which may explain the small amounts of observed cold gas in cloud cores and disk mid-planes. This paper aims to determine the UV photodesorption yields and to constrain the photodesorption mechanisms of three astrochemically relevant ices: CO, N2 and CO2. In addition, the possibility of co-desorption in mixed and layered CO:N2 ices is explored. The ice photodesorption is studied experimentally under ultra high vacuum conditions and at 15-60 K using a hydrogen discharge lamp (7-10.5 eV). The ice desorption during irradiation is monitored by reflection absorption infrared spectroscopy of the ice and simultaneous mass spectrometry of the desorbed molecules. Both the UV photodesorption yields per incident photon and the photodesorption mechanisms are molecule specific. CO photodesorbs without dissociation from the surface layer of the ice. N2, which lacks an electronic transition in this wavelength range, has a photodesorption yield that is more than an order of magnitude lower. This yield increases significantly due to co-desorption when N2 is mixed in with or layered on top of CO ice. CO2 photodesorbs through dissociation and subsequent recombination from the top 10 layers of the ice. At low temperatures (15-18 K) the derived photodesorption yields are 2.7x10^-3 and CO2 photodesorption yield is 1.2x10^-3x(1-e^(-X/2.9)) + 1.1x10^-3x(1-e^(-X/4.6)) molecules photon-1, where X is the ice thickness in monolayers and the two parts of the expression represent a CO2 and CO photodesorption pathway.

  19. Structural and dynamical properties of nanoconfined supercooled water

    E-Print Network [OSTI]

    Oriol Vilanova; Giancarlo Franzese

    2011-02-14T23:59:59.000Z

    Bulk water presents a large number of crystalline and amorphous ices. Hydrophobic nanoconfinement is known to affect the tendency of water to form ice and to reduce the melting temperature. However, a systematic study of the ice phases in nanoconfinement is hampered by the computational cost of simulations at very low temperatures. Here we develop a coarse-grained model for a water monolayer in hydrophobic nanoconfinement and study the formation of ice by Mote Carlo simulations. We find two ice phases: low-density-crystal ice at low pressure and high-density hexatic ice at high pressure, an intermediate phase between liquid and high-density-crystal ice.

  20. Phonons in a one-dimensional microfluidic crystal

    E-Print Network [OSTI]

    Tsevi Beatus; Tsvi Tlusty; Roy Bar-Ziv

    2010-08-06T23:59:59.000Z

    The development of a general theoretical framework for describing the behaviour of a crystal driven far from equilibrium has proved difficult1. Microfluidic crystals, formed by the introduction of droplets of immiscible fluid into a liquid-filled channel, provide a convenient means to explore and develop models to describe non-equilibrium dynamics2, 3, 4, 5, 6, 7, 8, 9, 10, 11. Owing to the fact that these systems operate at low Reynolds number (Re), in which viscous dissipation of energy dominates inertial effects, vibrations are expected to be over-damped and contribute little to their dynamics12, 13, 14. Against such expectations, we report the emergence of collective normal vibrational modes (equivalent to acoustic 'phonons') in a one-dimensional microfluidic crystal of water-in-oil droplets at Reapprox10-4. These phonons propagate at an ultra-low sound velocity of approx100 mum s-1 and frequencies of a few hertz, exhibit unusual dispersion relations markedly different to those of harmonic crystals, and give rise to a variety of crystal instabilities that could have implications for the design of commercial microfluidic systems. First-principles theory shows that these phonons are an outcome of the symmetry-breaking flow field that induces long-range inter-droplet interactions, similar in nature to those observed in many other systems including dusty plasma crystals15, 16, vortices in superconductors17, 18, active membranes19 and nucleoprotein filaments20.

  1. Multispecies weighted Hurwitz numbers

    E-Print Network [OSTI]

    Harnad, J

    2015-01-01T23:59:59.000Z

    The construction of hypergeometric 2D Toda $\\tau$-functions as generating functions for weighted Hurwitz numbers is extended to multispecies families. Both the enumerative geometrical significance of multispecies weighted Hurwitz numbers as weighted enumerations of branched coverings of the Riemann sphere and their combinatorial significance in terms of weighted paths in the Cayley graph of $S_n$ are derived. The particular case of multispecies quantum weighted Hurwitz numbers is studied in detail.

  2. Curvature and Tachibana numbers

    SciTech Connect (OSTI)

    Stepanov, Sergey E [Finance Academy under the Government of the Russian Federation, Moscow (Russian Federation)

    2011-07-31T23:59:59.000Z

    The aim of this paper is to define the rth Tachibana number t{sub r} of an n-dimensional compact oriented Riemannian manifold as the dimension of the space of conformally Killing r-forms, for r=1,2,...,n-1. We also describe properties of these numbers, by analogy with properties of the Betti numbers b{sub r} of a compact oriented Riemannian manifold. Bibliography: 25 titles.

  3. Vacuum-UV spectroscopy of interstellar ice analogs. II. Absorption cross-sections of nonpolar ice molecules

    E-Print Network [OSTI]

    Cruz-Diaz, G A; Chen, Y -J; Yih, T -S

    2014-01-01T23:59:59.000Z

    Dust grains in cold circumstellar regions and dark-cloud interiors at 10-20 K are covered by ice mantles. A nonthermal desorption mechanism is invoked to explain the presence of gas-phase molecules in these environments, such as the photodesorption induced by irradiation of ice due to secondary ultraviolet photons. To quantify the effects of ice photoprocessing, an estimate of the photon absorption in ice mantles is required. In a recent work, we reported the vacuum-ultraviolet (VUV) absorption cross sections of nonpolar molecules in the solid phase. The aim was to estimate the VUV-absorption cross sections of nonpolar molecular ice components, including CH4, CO2, N2, and O2. The column densities of the ice samples deposited at 8 K were measured in situ by infrared spectroscopy in transmittance. VUV spectra of the ice samples were collected in the 120-160 nm (10.33-7.74 eV) range using a commercial microwave-discharged hydrogen flow lamp. We found that, as expected, solid N2 has the lowest VUV-absorption cros...

  4. Spatial mapping of ices in the Oph-F core: A direct measurement of CO depletion and the formation of CO2

    E-Print Network [OSTI]

    K. M. Pontoppidan

    2006-05-22T23:59:59.000Z

    Aims: Ices in dense star-forming cores contain the bulk of volatile molecules apart from H2 and thus represent a large fraction of dark cloud chemistry budget.To directly constrain the freeze-out profile of CO, the formation route of CO2 and the carrier of the 6.8 micron band, the spatial distribution of the CO/CO2 ice system and the 6.8 micron band carrier are measured in a nearby dense core. Methods: VLT-ISAAC, ISOCAM-CVF and Spitzer-IRS archival mid-infrared (3-20 micron) spectroscopy of young stellar objects is used to construct a map of the abundances of CO and CO2 ices in the Oph-F star-forming core, probing core radii from 2 10^3 to 14 10^3 AU or densities from 5 10^4 to 5 10^5 cm^-3 with a resolution of ~ 3000 AU. Results: The line-of-sight averaged abundances relative to water ice of both CO and CO2 ices increase monotonously with decreasing distance to the core center. The map traces the shape of the CO abundance profile between freeze-out ratios of 5-60% and shows that the CO2 ice abundance increases by a factor of 2 as the CO freezes out. It is suggested that this indicates a formation route of CO2 on a CO ice surface to produce a CO2 component dilute in CO ice, in addition to a fraction of the CO2 formed at lower densities along with the water ice mantle. It is predicted that the CO2 bending mode band profile should reflect a high CO:CO2 number ratio in the densest parts of dark clouds. In contrast to CO and CO2, the abundance of the carrier of the 6.8 micron band remains relatively constant throughout the core. A simple freeze-out model of the CO abundance profile is used to estimate the binding energy of CO on a CO ice surface to 814+/-30 K.

  5. 1 | De-icing salt damage to trees | November 2011 Pathology Advisory Note

    E-Print Network [OSTI]

    1 | De-icing salt damage to trees | November 2011 Pathology Advisory Note (No. 11) De-icing salt damage to trees De-icing Salt Damage to Trees Joan F Webber, David R Rose, Martin C Dobson #12;2 | De-icing salt damage to trees | November 2011 S a l t D a m a g e De-icing Salt Damage Introduction Rock salt

  6. crystal nickel a hree dimension

    E-Print Network [OSTI]

    Braun, Paul

    Zhenting 1 Department 2 Departmen ABSTRACT This pape crystal nickel a hree dimension photonic cryst polystyrene op silicon chips, volume fraction can be controlle nickel structure hen sacrificed volume fraction reports microm crystal structur or alumina she nickel microca microstructure further electrop volume

  7. Nonisothermal kinetics of spinel crystallization in a HLW glass

    SciTech Connect (OSTI)

    Casler, D.G.; Hrma, P.

    1999-07-01T23:59:59.000Z

    Nonisothermal kinetics of spinel crystallization in a high-level waste (HLW) glass was predicted using Mehl-Avrami-Johnson-Kolmogorov equation coefficients from isothermal data. The volume fraction of spinel was determined as a function of time, temperature, and cooling rate. The results were verified experimentally. Also predicted was the spatial distribution of spinel in a HLW glass canister. Finally, a parameter study was performed, and an empirical equation was proposed relating the final spinel volume fraction in glass to dimensionless numbers for cooling rate, phase equilibrium, and crystallization kinetics.

  8. Definitions Numbered Space

    E-Print Network [OSTI]

    Behmer, Spencer T.

    Definitions · Numbered Space ­ a single space marked with a number and reserved for a single permit 24/7 · Unnumbered Space ­ a space which can be used by any customer allowed to park in that lot. High Low Average Question 4: If I buy a staff permit for an UNNUMBERED* space in a non-gated surface

  9. Determining Greenland Ice Sheet sensitivity to regional climate change: one-way coupling of a 3-D thermo-mechanical ice sheet model with a mesoscale climate model

    E-Print Network [OSTI]

    Schlegel, Nicole-Jeanne

    2011-01-01T23:59:59.000Z

    ice sheet model with a mesoscale climate model By Nicole-ice sheet model with a mesoscale climate model Copyrightice sheet model with a mesoscale climate model by Nicole-

  10. The influence of vegetation on frost dynamics, infiltration rate and surface stability in Icelandic Andisolic rangelands

    E-Print Network [OSTI]

    Orradottir, Berglind

    2002-01-01T23:59:59.000Z

    only occurred where vegetation cover was sparse. Seasonal changes in infiltration rates, measured with double-ring infiltrometers, varied with soil frost depth and type, as indicated by the depth of visible ice crystals and size and number of ice...

  11. Proton ordering dynamics of H2O ice

    E-Print Network [OSTI]

    Yen, Fei

    2015-01-01T23:59:59.000Z

    From high precision measurements of the complex dielectric constant of H2O ice, we identify the critical temperatures of the phase transition into and out of ice XI from ice Ih to occur at T_Ih-IX=58.9 K and T_IX-Ih=73.4 K. For D2O, T_Ih-IX=63.7 K and T_IX-Ih=78.2 K. A triple point is identified to exist at 0.07 GPa and 73.4 K for H2O and 0.08 GPa and 78.2 K for D2O where ices Ih, II and XI coexist. A first order phase transition with kinetic broadening associated to proton ordering dynamics is identified at 100 K.

  12. Immersion freezing of clay minerals and bacterial ice nuclei

    E-Print Network [OSTI]

    Hiranuma, Naruki

    2013-01-01T23:59:59.000Z

    The immersion mode ice nucleation efficiency of clay minerals and biological aerosols has been investigated using the AIDA (Aerosol Interaction and Dynamics in the Atmosphere) cloud chamber. Both monodisperse and polydisperse ...

  13. Ocean and Sea Ice SAF ASCAT NWP Ocean Calibration

    E-Print Network [OSTI]

    Stoffelen, Ad

    Ocean and Sea Ice SAF ASCAT NWP Ocean Calibration Jeroen Verspeek Anton Verhoef Ad Stoffelen Version 1.5 2011-03-16 #12;ASCAT NWP Ocean Calibration Contents 1 Introduction ....................................................................................................................3 2 NWP Ocean Calibration

  14. Shear measurements across the northern margin of Whillans Ice Stream

    E-Print Network [OSTI]

    Van Der Veen, C.J.; Jezek, K.; Stearns, Leigh

    2007-01-01T23:59:59.000Z

    Field measurements of surface deformation across the northern shear margin of Whillans Ice Stream, West Antarctica, were analyzed to better understand the processes controlling the position and migration of this margin. Four lines of poles extending...

  15. Composition of Ices in Low-Mass Extrasolar Planets

    E-Print Network [OSTI]

    Ulysse Marboeuf; Olivier Mousis; David Ehrenreich; Yann Alibert; Arnaud Cassan; Valentine Wakelam; Jean-Philippe Beaulieu

    2008-04-02T23:59:59.000Z

    We study the formation conditions of icy planetesimals in protoplanetary disks in order to determine the composition of ices in small and cold extrasolar planets. Assuming that ices are formed from hydrates, clathrates, and pure condensates, we calculate their mass fractions with respect to the total quantity of ices included in planetesimals, for a grid of disk models. We find that the composition of ices weakly depends on the adopted disk thermodynamic conditions, and is rather influenced by the initial composition of the gas phase. The use of a plausible range of molecular abundance ratios and the variation of the relative elemental carbon over oxygen ratio in the gas phase of protoplanetary disks, allow us to apply our model to a wide range of planetary systems. Our results can thus be used to constrain the icy/volatile phase composition of cold planets evidenced by microlensing surveys, hypothetical ocean-planets and carbon planets, which could be detected by Corot or Kepler.

  16. Composition of Ices in Low-Mass Extrasolar Planets

    E-Print Network [OSTI]

    Marboeuf, Ulysse; Ehrenreich, David; Alibert, Yann; Cassan, Arnaud; Wakelam, Valentine; Beaulieu, Jean-Philippe

    2008-01-01T23:59:59.000Z

    We study the formation conditions of icy planetesimals in protoplanetary disks in order to determine the composition of ices in small and cold extrasolar planets. Assuming that ices are formed from hydrates, clathrates, and pure condensates, we calculate their mass fractions with respect to the total quantity of ices included in planetesimals, for a grid of disk models. We find that the composition of ices weakly depends on the adopted disk thermodynamic conditions, and is rather influenced by the initial composition of the gas phase. The use of a plausible range of molecular abundance ratios and the variation of the relative elemental carbon over oxygen ratio in the gas phase of protoplanetary disks, allow us to apply our model to a wide range of planetary systems. Our results can thus be used to constrain the icy/volatile phase composition of cold planets evidenced by microlensing surveys, hypothetical ocean-planets and carbon planets, which could be detected by Corot or Kepler.

  17. TRACES Centre Thermo iCE 3500 Flame AA Spectrometer

    E-Print Network [OSTI]

    Wells, Mathew G. - Department of Physical and Environmental Sciences, University of Toronto

    TRACES Centre Thermo iCE 3500 Flame AA Spectrometer Standard Operating Procedure 1. Turn on the lamp icon a. ID the lamp of choice and click the `Off' button to `On' b. Non-Thermo lamps MUST

  18. The effect of selective desorption mechanisms during interstellar ice formation

    E-Print Network [OSTI]

    Kalvans, Juris

    2015-01-01T23:59:59.000Z

    Major components of ices on interstellar grains in molecular clouds - water and carbon oxides - occur at various optical depths. This implies that selective desorption mechanisms are at work. An astrochemical model of a contracting low-mass molecular cloud core is presented. Ice was treated as consisting of the surface and three subsurface layers (sublayers). Photodesorption, reactive desorption, and indirect reactive desorption were investigated. The latter manifests itself through desorption from H+H reaction on grains. Desorption of shallow subsurface species was included. Modeling results suggest the existence of a "photon-dominated ice" during the early phases of core contraction. Subsurface ice is chemically processed by interstellar photons, which produces complex organic molecules. Desorption from the subsurface layer results in high COM gas-phase abundances at Av = 2.4...10mag. This may contribute towards an explanation for COM observations in dark cores. It was found that photodesorption mostly gove...

  19. Crater ice deposits near the south pole of Mars

    E-Print Network [OSTI]

    Westbrook, Owen William

    2009-01-01T23:59:59.000Z

    Layered deposits atop both Martian poles are thought to preserve a record of past climatic conditions in up to three km of water ice and dust. Just beyond the extent of these south polar layered deposits (SPLD), dozens of ...

  20. Modelling the hydrology of the Greenland ice sheet 

    E-Print Network [OSTI]

    Karatay, Mehmet Rahmi

    2011-06-28T23:59:59.000Z

    This thesis aims to better understand the relationships between basal water pressure, friction, and sliding mechanisms at ice sheet scales. In particular, it develops a new subglacial hydrology model (Hydro) to explicitly ...

  1. Searching for Cosmic Accelerators via IceCube

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of the highest energy neutrinos ever reported, which have been named Bert and Ernie." The new results from IceCube, which were published in the journal Science, provide...

  2. IceCube Project Monthly Report January 2011 Accomplishments

    E-Print Network [OSTI]

    Saffman, Mark

    Raytheon responsibilities. The excitement generated by the completion of IceCube construction led at the end of December 2010 was a favorable $2.042M, primarily due to Raytheon and New York Air National

  3. Magnetization plateaus of dipolar spin ice on kagome lattice

    SciTech Connect (OSTI)

    Xie, Y. L.; Wang, Y. L.; Yan, Z. B.; Liu, J.-M., E-mail: liujm@nju.edu.cn [Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China)

    2014-05-07T23:59:59.000Z

    Unlike spin ice on pyrochlore lattice, the spin ice structure on kagome lattice retains net magnetic charge, indicating non-negligible dipolar interaction in modulating the spin ice states. While it is predicted that the dipolar spin ice on kagome lattice exhibits a ground state with magnetic charge order and ?3?×??3 spin order, our work focuses on the magnetization plateau of this system. By employing the Wang-Landau algorithm, it is revealed that the lattice exhibits the fantastic three-step magnetization in response to magnetic field h along the [10] and [01] directions, respectively. For the h//[1 0] case, an additional ?3/6M{sub s} step, where M{sub s} is the saturated magnetization, is observed in a specific temperature range, corresponding to a new state with charge order and short-range spin order.

  4. Hydrological and biogeochemical cycling along the Greenland ice sheet margin

    E-Print Network [OSTI]

    Bhatia, Maya Pilar, 1979-

    2012-01-01T23:59:59.000Z

    Global warming has led to a significant increase in Greenland ice sheet (GrIS) melt and runoff since 1990, resulting in escalated export of fresh water and associated sediment to the surrounding North Atlantic and Arctic ...

  5. Periodic fluctuations in deep water formation due to sea ice

    E-Print Network [OSTI]

    Saha, Raj

    2015-01-01T23:59:59.000Z

    During the last ice age several quasi-periodic abrupt warming events took place. Known as Dansgaard-Oeschger (DO) events their effects were felt globally, although the North Atlantic experienced the largest temperature anomalies. Paleoclimate data shows that the fluctuations often occurred right after massive glacial meltwater releases in the North Atlantic and in bursts of three or four with progressively decreasing strengths. In this study a simple dynamical model of an overturning circulation and sea ice is developed with the goal of understanding the fundamental mechanisms that could have caused the DO events. Interaction between sea ice and the overturning circulation in the model produces self-sustained oscillations. Analysis and numerical experiments reveal that the insulating effect of sea ice causes the ocean to periodically vent out accumulated heat in the deep ocean into the atmosphere. Subjecting the model to idealized freshwater forcing mimicking Heinrich events causes modulation of the natural p...

  6. Sea ice floes dissipate the energy of steep ocean waves

    E-Print Network [OSTI]

    Toffoli, Alessandro; Meylan, Michael H; Cavaliere, Claudio; Alberello, Alberto; Elsnab, John; Monty, Jason P

    2015-01-01T23:59:59.000Z

    Wave attenuation by ice floes is an important parameter for modelling the Arctic Oceans. At present, attenuation coefficients are extracted from linear models as a function of the incident wave period and floe thickness. Recent explorations in the Antarctic Mixed Ice Zone (MIZ) revealed a further dependence on wave amplitude, suggesting that nonlinear contributions are non-negligible. An experimental model for wave attenuation by a single ice floe in a wave flume is here presented. Observations are compared with linear predictions based on wave scattering. Results indicate that linear models perform well under the effect of gently sloping waves. For more energetic wave fields, however, transmitted wave height is normally over predicted. Deviations from linearity appear to be related to an enhancement of wave dissipation induced by unaccounted wave-ice interaction processes, including the floe over wash.

  7. CRYSTALLIZATION IN HIGH-LEVEL WASTE GLASSES U.S. DEPARTMENT OF ENERGY OFFICE OF RIVER PROTECTION WTP ENGINEERING DIVISION

    SciTech Connect (OSTI)

    KRUGER AA; HRMA PR

    2009-08-19T23:59:59.000Z

    Various circumstances influence crystallization in glassmaking, for example: (1) crystals nucleate and grow before the glass-forming melt occurs; (2) crystals grow or dissolve in flowing melt and during changing temperature; (3) crystals move under the influence of gravity; (4) crystals agglomerate and interact with gas bubbles; (5) high-level wastes (HLW) are mixtures of a large number of components in unusual proportions; (6) melter processing of HLW and the slow cooling of HLW glass in canisters provides an opportunity for a variety of crystalline forms to precipitate; (7) settling of crystals in a HLW glass melter may produce undesirable sludge at the melter bottom; and (8) crystallization of the glass product may increase, but also ruin chemical durability. The conclusions are: (1) crystal growth and dissolution typically proceed in a convective medium at changing temperature; (2) to represent crystallization or dissolution the kinetics must be expressed in the form of rate equations, such as dC/dt = f(C,T) and the temperature dependence of kinetic coefficients and equilibrium concentrations must be accounted for; and (3) non-equilibrium phenomena commonly occur - metastable crystallization, periodic distribution of crystals; and dendritic crystal growth.

  8. Biochemical changes in speckled trout (Cynoscion nebulosus) preserved with ice

    E-Print Network [OSTI]

    Glover, James Donald

    1970-01-01T23:59:59.000Z

    BIOCHEMICAL CHANGES IN SPECKLED TROUT (CYNOSCION NEBULOSUS) PRESERVED WITH ICE A Thesis by JAMES DONALD GLOVER Approved as to style and content by: (C irman of Committee) emb ) (Head of Depa tment) (Member ) August 1970 ABSTRACT... Biochemical Changes in Speckled Trout (Cynoscion Nebulosus) Preserved with Ice. (August 1970) James Donald Glover, B. S. , Texas A&M University Directed by: Bryant F. Cobb III One hundred-sixty speckled trout were purchased from retail fish markets...

  9. Atmospheric neutrino oscillations and tau neutrinos in ice

    E-Print Network [OSTI]

    Gerardo Giordano; Olga Mena; Irina Mocioiu

    2010-04-20T23:59:59.000Z

    The main goal of the IceCube Deep Core Array is to search for neutrinos of astrophysical origins. Atmospheric neutrinos are commonly considered as a background for these searches. We show here that cascade measurements in the Ice Cube Deep Core Array can provide strong evidence for tau neutrino appearance in atmospheric neutrino oscillations. A careful study of these tau neutrinos is crucial, since they constitute an irreducible background for astrophysical neutrino detection.

  10. Elastic Coulomb-levitation: why is ice so slippery?

    E-Print Network [OSTI]

    Chang Q. Sun

    2015-02-14T23:59:59.000Z

    The elastic, less dense, polarized, and thermally stable supersolid skin lubricates ice. Molecular undercoordination shortens the H-O bond and lengthens the O:H nonbond through O-O repulsion, which is associated with low-frequency and high-magnitude of O:H vibration and a dual O-O polarization. The softer O:H springs attached with stronger molecular dipoles provide forces levitating objects sliding on ice, like Maglev or Hovercraft.

  11. Comment on Magnetic Monopole Excitations in Spin Ice

    E-Print Network [OSTI]

    Subir Ghosh

    2008-01-21T23:59:59.000Z

    It has been proposed recently \\cite{son} that excitations in Spin Ice can be of the form of magnetic monopoles that does not obey the Dirac Quantization Condition. It is also well known \\cite{rj} that the above scenario leads to non-associativity among translation generators. It will be interesting to see how the monopole picture in Spin Ice survives in the light of the latter observation.

  12. Structure order, local potentials, and physical anomalies of water ice

    E-Print Network [OSTI]

    Chang Q Sun

    2014-07-11T23:59:59.000Z

    Hydrogen-bond forms a pair of asymmetric, coupled, H-bridged oscillators with ultra-short-range interactions and memory. hydrogen bond cooperative relaxation and the associated binding electron entrapment and nonbonding electron polarization discriminate water and ice from other usual materials in the physical anomalies. As a strongly correlated fluctuating system, water prefers the statistically mean of tetrahedrally-coordinated structure with a supersolid skin that is elastic, polarized, ice like, hydrophobic, with 3/4 density.

  13. Variations in the age of Arctic sea-ice and summer sea-ice extent Ignatius G. Rigor1,2

    E-Print Network [OSTI]

    Rigor, Ignatius G.

    pack is determined by the effects of the atmosphere and ocean upon the sea-ice on various time scalesVariations in the age of Arctic sea-ice and summer sea-ice extent Ignatius G. Rigor1,2 and John M] Three of the past six summers have exhibited record low sea-ice extent on the Arctic Ocean. These minima

  14. Decline in ice thickness from sub data 1 10/16/07 The decline in arctic sea-ice thickness: separating the spatial, annual, and1

    E-Print Network [OSTI]

    Percival, Don

    Decline in ice thickness from sub data 1 10/16/07 The decline in arctic sea-ice thickness/14/07 & 10/16/079 10 11 #12;Decline in ice thickness from sub data 2 10/16/07 Abstract11 Naval submarines have collected operational data of sea-ice draft (90% of thickness) in the12 Arctic Ocean since 1958

  15. Lamella settler crystallizer

    DOE Patents [OSTI]

    Maimoni, A.

    1990-12-18T23:59:59.000Z

    A crystallizer is described which incorporates a lamella settler and which is particularly applicable for use in batteries and power cells for electric vehicles or stationary applications. The lamella settler can be utilized for coarse particle separation or for agglomeration, and is particularly applicable to aluminum-air batteries or power cells for solving the hydrargillite (aluminum-hydroxide) removal problems from such batteries. This invention provides the advantages of very low energy consumption, turbulence, shear, cost and maintenance. Thus, due to the low shear and low turbulence of this invention, it is particularly effective in the control of aluminum hydroxide particle size distribution in the various sections of an aluminum-air system, as well as in other electrochemical systems requiring separation for phases of different densities. 3 figs.

  16. Lamella settler crystallizer

    DOE Patents [OSTI]

    Maimoni, Arturo (Orinda, CA)

    1990-01-01T23:59:59.000Z

    A crystallizer which incorporates a lamella settler and which is particularly applicable for use in batteries and power cells for electric vehicles or stationary applications. The lamella settler can be utilized for coarse particle separation or for agglomeration, and is particularly applicable to aluminum-air batteries or power cells for solving the hydrargillite (aluminum-hydroxide) removal problems from such batteries. This invention provides the advantages of very low energy consumption, turbulence, shear, cost and maintenance. Thus, due to the low shear and low turbulence of this invention, it is particularly effective in the control of aluminum hydroxide particle size distribution in the various sections of an aluminum-air system, as well as in other electrochemical systems requiring separation for phases of different densities.

  17. Frequency mixing crystal

    DOE Patents [OSTI]

    Ebbers, Christopher A. (Livermore, CA); Davis, Laura E. (Manteca, CA); Webb, Mark (Salida, CA)

    1992-01-01T23:59:59.000Z

    In a laser system for converting infrared laser light waves to visible light comprising a source of infrared laser light waves and means of harmoic generation associated therewith for production of light waves at integral multiples of the frequency of the original wave, the improvement of said means of harmonic generation comprising a crystal having the chemical formula X.sub.2 Y(NO.sub.3).sub.5 .multidot.2 nZ.sub.2 o wherein X is selected from the group consisting of Li, Na, K, Rb, Cs, and Tl; Y is selected from the group consisting of Sc, Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga, and In; Z is selected from the group consisting of H and D; and n ranges from 0 to 4.

  18. Shear strength of ice rubble in laboratory tests

    SciTech Connect (OSTI)

    Lehmus, E.; Kaernae, T.

    1995-12-31T23:59:59.000Z

    The values of shear strength of the ice rubble in the ridge keels and rubble fields are important in force computations. To increase the data on ridge properties, the shear strength of partially consolidated ice rubble was studied by making tests in a shear box. The only variable was the consolidation time. The tests were done in a simple shear box in which the top and bottom of the ice are not confined. The dimensions of the box were 0.96 m in length, 0.8 m in width and 0.8 m in height. The upper part of the box was pulled with the carriage. The ice field was sawn in blocks in order to get a controlled block size distribution. The size distribution for the ice blocks was selected to correspond published data on full-scale ice ridges. The measured mean values of shear strength varied from 1 kPa to 17 kPa depending on the freezing conditions.

  19. IceCube: An Instrument for Neutrino Astronomy

    SciTech Connect (OSTI)

    IceCube Collaboration; Halzen, F.; Klein, S.

    2010-06-04T23:59:59.000Z

    Neutrino astronomy beyond the Sun was first imagined in the late 1950s; by the 1970s, it was realized that kilometer-scale neutrino detectors were required. The first such instrument, IceCube, is near completion and taking data. The IceCube project transforms a cubic kilometer of deep and ultra-transparent Antarctic ice into a particle detector. A total of 5,160 optical sensors are embedded into a gigaton of Antarctic ice to detect the Cherenkov light emitted by secondary particles produced when neutrinos interact with nuclei in the ice. Each optical sensor is a complete data acquisition system, including a phototube, digitization electronics, control and trigger systems and LEDs for calibration. The light patterns reveal the type (flavor) of neutrino interaction and the energy and direction of the neutrino, making neutrino astronomy possible. The scientific missions of IceCube include such varied tasks as the search for sources of cosmic rays, the observation of Galactic supernova explosions, the search for dark matter, and the study of the neutrinos themselves. These reach energies well beyond those produced with accelerator beams.

  20. A Supersolid Skin Covering both Water and Ice

    E-Print Network [OSTI]

    Sun, Chang Q

    2014-01-01T23:59:59.000Z

    The mysterious nature and functionality of water and ice skins remain baffling to the community since 1859 when Farady firstly proposed liquid skin lubricating ice. Here we show the presence of supersolid phase that covers both water and ice using Raman spectroscopy measurements and quantum calculations. In the skin of two molecular layers thick, molecular undercoordination shortens the H-O bond by ~16% and lengthens the OH nonbond by ~25% through repulsion between electron pairs on adjacent O atoms, which depresses the density from 0.92 for bulk ice to 0.75 gcm-3. The O:H-O cooperative relaxation stiffens the H-O stretching phonon from 3200/3150 cm-1 to the same value of 3450 cm-1 and raises the melting temperature of both skins by up to ~310 K. Numerical derivatives on the viscosity and charge accumulation suggests that the elastic, polarized, and thermally stable supersolid phase makes the ice frictionless and water skin hydrophobic and ice like at room temperature.

  1. Controlling single and few-layer graphene crystals growth in a solid carbon source based chemical vapor deposition

    SciTech Connect (OSTI)

    Papon, Remi; Sharma, Subash; Shinde, Sachin M.; Vishwakarma, Riteshkumar; Tanemura, Masaki [Department of Frontier Materials, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Kalita, Golap, E-mail: kalita.golap@nitech.ac.jp [Department of Frontier Materials, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555 (Japan); Center for Fostering Young and Innovative Researchers, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, 466-8555 (Japan)

    2014-09-29T23:59:59.000Z

    Here, we reveal the growth process of single and few-layer graphene crystals in the solid carbon source based chemical vapor deposition (CVD) technique. Nucleation and growth of graphene crystals on a polycrystalline Cu foil are significantly affected by the injection of carbon atoms with pyrolysis rate of the carbon source. We observe micron length ribbons like growth front as well as saturated growth edges of graphene crystals depending on growth conditions. Controlling the pyrolysis rate of carbon source, monolayer and few-layer crystals and corresponding continuous films are obtained. In a controlled process, we observed growth of large monolayer graphene crystals, which interconnect and merge together to form a continuous film. On the other hand, adlayer growth is observed with an increased pyrolysis rate, resulting few-layer graphene crystal structure and merged continuous film. The understanding of monolayer and few-layer crystals growth in the developed CVD process can be significant to grow graphene with controlled layer numbers.

  2. Arctic sea ice extent small as never before Alerting message from the Arctic: The extent the the Arctic sea ice has reached on Sep. 8

    E-Print Network [OSTI]

    Bremen, Universität

    Arctic sea ice extent small as never before Alerting message from the Arctic: The extent the the Arctic sea ice has reached on Sep. 8 with 4.240 million km2 a new historic minimum (Figure 1). Physicists of the University of Bremen now confirm the apprehension existing since July 2011 that the ice melt in the Arctic

  3. 115 year ice-core data from Akademii Nauk ice cap, Severnaya Zemlya: high-resolution record of Eurasian Arctic climate change

    E-Print Network [OSTI]

    Fischer, Hubertus

    ice core has been drilled within the framework of the European Project for Ice Coring in Antarctica of Antarctica. Drilling reached bedrock during the last field season 2005/06 providing ice over a time span. Since Ca2+ is derived from terrestrial dust and marine sources, the non-sea-salt calcium concentrations

  4. 07/06/2009 Melting Ice Could Lead to Massive Waves of Climate Refugees Treehugger 06/30/2009 MELTING GREENLAND ICE SHEETS MAY THREATEN

    E-Print Network [OSTI]

    Hu, Aixue

    /30/2009 MELTING GREENLAND ICE SHEETS MAY THREATEN NORTHEAST U.S., CANADA Federal News Service 06/30/2009 Sea raises spectre of displaced humanity peopleandplanet.net 06/16/2009 Melting Greenland Ice Sheets May Report - Online 06/02/2009 Melting Greenland Ice Sheets May Threaten Northeast, Canada usagnet 06

  5. Probabilistic calibration of a Greenland Ice Sheet model using spatially-resolved synthetic observations: toward projections of ice mass loss with uncertainties

    E-Print Network [OSTI]

    Haran, Murali

    1 Probabilistic calibration of a Greenland Ice Sheet model using spatially-resolved synthetic on how well the model reproduces the Greenland Ice Sheet profile. We improve on the previous state et al., 2012). Here, we focus on the Greenland Ice Sheet component of future sea level rise

  6. IGS 2000: RGPS Albedo June 15, 2001 1 Arctic sea ice albedo derived from RGPS-based

    E-Print Network [OSTI]

    Lindsay, Ron

    of Arctic pack ice ia a highly significant factor for establishing the energy balance of the ice. The netIGS 2000: RGPS Albedo June 15, 2001 1 Arctic sea ice albedo derived from RGPS-based ice thickness Geophysical Processor System (RGPS) uses sequential synthetic aperture radar images of Arctic sea ice taken

  7. Observations of unusual fast-ice conditions in the southwest Ross Sea, Antarctica: preliminary analysis of iceberg and

    E-Print Network [OSTI]

    Boyce, C. Kevin

    ice (referred to as pack ice) which had several days earlier been part of the integrated AnnalsObservations of unusual fast-ice conditions in the southwest Ross Sea, Antarctica: preliminary of their presence, extensive landfast sea ice (fast ice) waxed and waned along the Victoria Land coast, with maximum

  8. View of NY harbor from the JOIDES Resolution! in an ice-free world (73 m rise)!

    E-Print Network [OSTI]

    Caps:! Melting land ice adds to ocean volume, but not sea ice! IPCC2001! Alpine! #12;Why Is global sea level Is rising today?! .! Melting mountain glaciers/ice caps ("alpine" and! continental ice sheets error: 20-60 cm (does not include ice sheet melting)! http://www.realclimate.org/images/sealevel_1.jpg

  9. Crystal Structure Representations for Machine Learning Models of Formation Energies

    E-Print Network [OSTI]

    Faber, Felix; von Lilienfeld, O Anatole; Armiento, Rickard

    2015-01-01T23:59:59.000Z

    We introduce and evaluate a set of feature vector representations of crystal structures for machine learning (ML) models of formation energies of solids. ML models of atomization energies of organic molecules have been successful using a Coulomb matrix representation of the molecule. We consider three ways to generalize such representations to periodic systems: (i) a matrix where each element is related to the Ewald sum of the electrostatic interaction between two different atoms in the unit cell repeated over the lattice; (ii) an extended Coulomb-like matrix that takes into account a number of neighboring unit cells; and (iii) an Ansatz that mimics the periodicity and the basic features of the elements in the Ewald sum matrix by using a sine function of the crystal coordinates of the atoms. The representations are compared for a Laplacian kernel with Manhattan norm, trained to reproduce formation energies using a data set of 3938 crystal structures obtained from the Materials Project. For training sets consi...

  10. Collisions of small ice particles under microgravity conditions (II): Does the chemical composition of the ice change the collisional properties?

    E-Print Network [OSTI]

    Hill, C R; Blum, J; Fraser, H J

    2015-01-01T23:59:59.000Z

    Context: Understanding the collisional properties of ice is important for understanding both the early stages of planet formation and the evolution of planetary ring systems. Simple chemicals such as methanol and formic acid are known to be present in cold protostellar regions alongside the dominant water ice; they are also likely to be incorporated into planets which form in protoplanetary disks, and planetary ring systems. However, the effect of the chemical composition of the ice on its collisional properties has not yet been studied. Aims: Collisions of 1.5 cm ice spheres composed of pure crystalline water ice, water with 5% methanol, and water with 5% formic acid were investigated to determine the effect of the ice composition on the collisional outcomes. Methods: The collisions were conducted in a dedicated experimental instrument, operated under microgravity conditions, at relative particle impact velocities between 0.01 and 0.19 m s^-1, temperatures between 131 and 160 K and a pressure of around 10^-5...

  11. Ice Nucleation of Fungal Spores from the Classes Agaricomycetes, Ustilaginomycetes, and Eurotiomycetes, and the effect on the Atmospheric Transport of these Spores

    SciTech Connect (OSTI)

    Haga, D. I.; Burrows, Susannah M.; Iannone, R.; Wheeler, M. J.; Mason, R.; Chen, J.; Polishchuk, E. A.; Poschl, U.; Bertram, Allan K.

    2014-08-26T23:59:59.000Z

    Ice nucleation on fungal spores may affect the frequency and properties of ice and mixed-phase clouds. We studied the ice nucleation properties of 12 different species of fungal spores chosen from three classes: Agaricomycetes, Ustilagomycetes, and Eurotiomycetes. Agaricomycetes include many types of mushroom species and are cosmopolitan all over the globe. Ustilagomycetes are agricultural pathogens and have caused widespread damage to crops. Eurotiomycetes are found on all types of decaying material and include important human allergens. We focused on these classes since they are thought to be abundant in the atmosphere and because there is very little information on the ice nucleation ability of these classes of spores in the literature. All of the fungal spores investigated were found to cause freezing of water droplets at temperatures warmer than homogeneous freezing. The cumulative number of ice nuclei per spore was 0.001 at temperatures between -19 °C and -29 °C, 0.01 between -25.5 °C and -31 °C, and 0.1 between -26 °C and -36 °C. On average, the order of ice nucleating ability for these spores is Ustilagomycetes > Agaricomycetes ? Eurotiomycetes. We show that at temperatures below -20 °C, all of the fungal spores studied here are less efficient ice nuclei compared to Asian mineral dust on a per surface area basis. We used our new freezing results together with data in the literature to compare the freezing temperatures of spores from the phyla Basidiomycota and Ascomycota, which together make up 98 % of known fungal species found on Earth. The data show that within both phyla (Ascomycota and Basidiomycota) there is a wide range of freezing properties, and also that the variation within a phylum is greater than the variation between the average freezing properties of the phyla. Using a global chemistry-climate transport model, we investigated whether ice nucleation on the studied spores, followed by precipitation, can influence the atmospheric transport and global distributions of these spores in the atmosphere. Simulations show that inclusion of ice nucleation scavenging of fungal spores in mixed-phase clouds can decrease the surface annual mean mixing ratios of fungal spores over the oceans and polar regions and decrease annual mean mixing ratios in the upper troposphere.

  12. Attenuation of acoustic waves in glacial ice and salt domes

    E-Print Network [OSTI]

    P. B. Price

    2005-06-27T23:59:59.000Z

    Two classes of natural solid media (glacial ice and salt domes) are under consideration as media in which to deploy instruments for detection of neutrinos with energy >1e18 eV. Though insensitive to 1e11 to 1e16 eV neutrinos for which observatories (e.g., AMANDA and IceCube) that utilize optical Cherenkov radiation detectors are designed, radio and acoustic methods are suited for searches for the very low fluxes of neutrinos with energies >1017 eV. This is because, due to the very long attenuation lengths of radio and acoustic waves in ice and salt, detection modules can be spaced very far apart. In this paper, I calculate the absorption and scattering coefficients as a function of frequency and grain size for acoustic waves in glacial ice and salt domes and show that experimental measurements on laboratory samples and in glacial ice and salt domes are consistent with theory. For South Pole ice with grain size 0.2 cm at -51 degrees C, scattering lengths are calculated to be 2000 km and 25 km at 10 kHz and 30 kHz, respectively, and the absorption length is calculated to be 9 km at frequencies above 100 Hz. For NaCl (rock salt) with grain size 0.75 cm, scattering lengths are calculated to be 120 km and 1.4 km at 10 kHz and 30 kHz, and absorption lengths are calculated to be 30,000 km and 3300 km at 10 kHz and 30 kHz. Existing measurements are consistent with theory. For ice, absorption is the limiting factor; for salt, scattering is the limiting factor.

  13. Ices in the Galactic Centre : solid ice and gaseous CO in the central parsec

    E-Print Network [OSTI]

    Moultaka, Jihane; Sabha, Nadeen

    2015-01-01T23:59:59.000Z

    For the past few years, we have observed the central half parsec of our Galaxy in the mid-infrared from 2.8 to 5.1 micron. Our aim is to improve our understanding of the direct environment of SgrA*, the supermassive blackhole at the centre of the Milky Way. This work is described in the present paper and by Moultaka et al. 2015 (submitted). Here, we focus on the study of the spatial distribution of the 12CO ice and gas-phase absorptions. We observed the central half parsec with ISAAC spectrograph located at the UT3/VLT ESO telescope in Chile. The slit was placed along 22 positions arranged parallel to each other to map the region. We built the first data cube in this wavelength range covering the central half parsec. The wavelength interval of the used M-band filter ranges from 4.6 to 5.1 micron. It hosts the P- and R- branches of the ro-vibrational transitions of the gaseous 12CO and 13CO, as well as the absorption band attributed to the 12CO ice at 4.675 micron. Using two calibrators, we could disentangle t...

  14. ON THE FORMATION OF INTERSTELLAR WATER ICE: CONSTRAINTS FROM A SEARCH FOR HYDROGEN PEROXIDE ICE IN MOLECULAR CLOUDS

    SciTech Connect (OSTI)

    Smith, R. G.; Wright, C. M.; Robinson, G. [School of Physical, Environmental and Mathematical Sciences, University of New South Wales, Australian Defence Force Academy, Canberra, ACT 2600 (Australia); Charnley, S. B. [Astrochemistry Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Pendleton, Y. J. [NASA Lunar Science Institute, NASA Ames Research Center, Moffett Field, CA 94035 (United States); Maldoni, M. M., E-mail: r.smith@adfa.edu.au, E-mail: c.wright@adfa.edu.au, E-mail: g.robinson@adfa.edu.au, E-mail: Steven.B.Charnley@nasa.gov, E-mail: yvonne.pendleton@nasa.gov [Geoscience Australia, Canberra, ACT 2601 (Australia)

    2011-12-20T23:59:59.000Z

    Recent surface chemistry experiments have shown that the hydrogenation of molecular oxygen on interstellar dust grains is a plausible formation mechanism, via hydrogen peroxide (H{sub 2}O{sub 2}), for the production of water (H{sub 2}O) ice mantles in the dense interstellar medium. Theoretical chemistry models also predict the formation of a significant abundance of H{sub 2}O{sub 2} ice in grain mantles by this route. At their upper limits, the predicted and experimental abundances are sufficiently high that H{sub 2}O{sub 2} should be detectable in molecular cloud ice spectra. To investigate this further, laboratory spectra have been obtained for H{sub 2}O{sub 2}/H{sub 2}O ice films between 2.5 and 200 {mu}m, from 10 to 180 K, containing 3%, 30%, and 97% H{sub 2}O{sub 2} ice. Integrated absorbances for all the absorption features in low-temperature H{sub 2}O{sub 2} ice have been derived from these spectra. For identifying H{sub 2}O{sub 2} ice, the key results are the presence of unique features near 3.5, 7.0, and 11.3 {mu}m. Comparing the laboratory spectra with the spectra of a group of 24 protostars and field stars, all of which have strong H{sub 2}O ice absorption bands, no absorption features are found that can definitely be identified with H{sub 2}O{sub 2} ice. In the absence of definite H{sub 2}O{sub 2} features, the H{sub 2}O{sub 2} abundance is constrained by its possible contribution to the weak absorption feature near 3.47 {mu}m found on the long-wavelength wing of the 3 {mu}m H{sub 2}O ice band. This gives an average upper limit for H{sub 2}O{sub 2}, as a percentage of H{sub 2}O, of 9% {+-} 4%. This is a strong constraint on parameters for surface chemistry experiments and dense cloud chemistry models.

  15. Report number codes

    SciTech Connect (OSTI)

    Nelson, R.N. (ed.)

    1985-05-01T23:59:59.000Z

    This publication lists all report number codes processed by the Office of Scientific and Technical Information. The report codes are substantially based on the American National Standards Institute, Standard Technical Report Number (STRN)-Format and Creation Z39.23-1983. The Standard Technical Report Number (STRN) provides one of the primary methods of identifying a specific technical report. The STRN consists of two parts: The report code and the sequential number. The report code identifies the issuing organization, a specific program, or a type of document. The sequential number, which is assigned in sequence by each report issuing entity, is not included in this publication. Part I of this compilation is alphabetized by report codes followed by issuing installations. Part II lists the issuing organization followed by the assigned report code(s). In both Parts I and II, the names of issuing organizations appear for the most part in the form used at the time the reports were issued. However, for some of the more prolific installations which have had name changes, all entries have been merged under the current name.

  16. Crystal-Like geometric modeling

    E-Print Network [OSTI]

    Landreneau, Eric Benjamin

    2006-08-16T23:59:59.000Z

    faces, symmetry, and fractal geometry. The techniques have also been implemented in software, as a proof of concept. They are used in an interactive geometric modeling system, in which users can use these techniques to create crystal-like shapes...

  17. Arnold Schwarzenegger SINGLE CRYSTAL SILICON

    E-Print Network [OSTI]

    in this report. #12;ENERGY INNOVATIONS SMALL GRANT (EISG) PROGRAM INDEPENDENT ASSESSMENT REPORT (IAR) SINGLEArnold Schwarzenegger Governor SINGLE CRYSTAL SILICON SHEET GROWTH Prepared For: California Energy Commission Energy Innovations Small Grant Program Prepared By: Energy Materials Research

  18. Active materials in photonic crystals

    E-Print Network [OSTI]

    Bermel, Peter (Peter A.)

    2007-01-01T23:59:59.000Z

    I analyze new phenomena arising from embedding active materials inside of photonic crystal structures. These structures strongly modify the photonic local density of states (LDOS), leading to quantitative and qualitative ...

  19. Crystal-Tolerant Glass Approach For Mitigation Of Crystal Accumulation In Continuous Melters Processing Radioactive Waste

    SciTech Connect (OSTI)

    Kruger, Albert A. [Department of Energy, Office of River Protection, Richland, Washington (United States); Rodriguez, Carmen P. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Lang, Jesse B. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Huckleberry, Adam R. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Matyas, Josef [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Owen, Antoinette T. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)

    2012-08-28T23:59:59.000Z

    High-level radioactive waste melters are projected to operate in an inefficient manner as they are subjected to artificial constraints, such as minimum liquidus temperature (T{sub L}) or maximum equilibrium fraction of crystallinity at a given temperature. These constraints substantially limit waste loading, but were imposed to prevent clogging of the melter with spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr){sub 2}O{sub 4}]. In the melter, the glass discharge riser is the most likely location for crystal accumulation during idling because of low glass temperatures, stagnant melts, and small diameter. To address this problem, a series of lab-scale crucible tests were performed with specially formulated glasses to simulate accumulation of spinel in the riser. Thicknesses of accumulated layers were incorporated into empirical model of spinel settling. In addition, T{sub L} of glasses was measured and impact of particle agglomeration on accumulation rate was evaluated. Empirical model predicted well the accumulation of single crystals and/or smallscale agglomerates, but, excessive agglomeration observed in high-Ni-Fe glass resulted in an under-prediction of accumulated layers, which gradually worsen over time as an increased number of agglomerates formed. Accumulation rate of ~14.9 +- 1 nm/s determined for this glass will result in ~26 mm thick layer in 20 days of melter idling.

  20. Sources of spread in simulations of Arctic sea ice loss over the twenty-first century: A letter

    E-Print Network [OSTI]

    Boé, Julien; Hall, Alex; Qu, Xin

    2010-01-01T23:59:59.000Z

    the ultimate fate of the ice pack. 1 Introduction Over theof the entire year’s ice pack (Fig. 3b). The relationshipultimate fate of the Arctic ice pack. In Boé et al. (2009b)