Sample records for assessing surface ice

  1. 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

  2. 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

  3. 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 ...

  4. 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.

  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. 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

  7. 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

  8. 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

  9. 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.

  10. 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...

  11. Formation of lobate debris aprons on Mars: Assessment of regional ice sheet collapse and debris-cover armoring

    E-Print Network [OSTI]

    Marchant, David R.

    not have attained temperatures near or above the ice melting point and retained their current shape, a findFormation of lobate debris aprons on Mars: Assessment of regional ice sheet collapse and debris Keywords: Mars, climate Mars, surface Mars, polar geology Mars, polar caps a b s t r a c t Lobate debris

  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. Surface Science Letters P) reactions with small alkenes adsorbed on Rh, Au, and ice

    E-Print Network [OSTI]

    Sibener, Steven

    Surface Science Letters O(3 P) reactions with small alkenes adsorbed on Rh, Au, and ice K.D. Gibson the reaction of O(3 P) with 1- and 2-butene on the surface of Rh(111) and ice, and propene on the surface of Au(111) and amorphous ice and propene adsorbed on Au(111). These experiments were done at cryogenic

  14. Assessment of Future ICE and Fuel-Cell Powered Vehicles and Their...

    Broader source: Energy.gov (indexed) [DOE]

    Assessment of Future ICE and Fuel-Cell Powered Vehicles and Their Potential Impacts Assessment of Future ICE and Fuel-Cell Powered Vehicles and Their Potential Impacts 2004 Diesel...

  15. 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

  16. 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.

  17. 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

  18. Decay of the Greenland Ice Sheet due to surface-meltwater-induced acceleration of basal sliding

    E-Print Network [OSTI]

    Greve, Ralf

    2009-01-01T23:59:59.000Z

    Simulations of the Greenland Ice Sheet are carried out with a high-resolution version of the ice-sheet model SICOPOLIS for several global-warming scenarios for the period 1990-2350. In particular, the impact of surface-meltwater-induced acceleration of basal sliding on the stability of the ice sheet is investigated. A parameterization for the acceleration effect is developed for which modelled and measured mass losses of the ice sheet in the early 21st century agree well. The main findings of the simulations are: (i) the ice sheet is generally very susceptible to global warming on time-scales of centuries, (ii) surface-meltwater-induced acceleration of basal sliding leads to a pronounced speed-up of ice streams and outlet glaciers, and (iii) this ice-dynamical effect accelerates the decay of the Greenland Ice Sheet as a whole significantly, but not catastrophically, in the 21st century and beyond.

  19. Assessment of Future ICE and Fuel-Cell Powered Vehicles and Their...

    Broader source: Energy.gov (indexed) [DOE]

    San Diego, CA August 29 - September 2, 2004 Assessment of Future ICE and Fuel-Cell Powered Vehicles and Their Potential Impacts 082904 "The fundamental problem is that...

  20. Greenland Ice Sheet Surface Air Temperature Variability: 18402007* JASON E. BOX

    E-Print Network [OSTI]

    Howat, Ian M.

    Greenland Ice Sheet Surface Air Temperature Variability: 1840­2007* JASON E. BOX Byrd Polar, seasonal, and annual mean Greenland ice sheet near- surface air temperatures. Independent observations Greenland in autumn and southern Greenland in winter. Spring trends marked the 1920s warming onset, while

  1. 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 Ã...

  2. Relating Microwave Backscatter Azimuth Modulation to Surface Properties of the Greenland Ice Sheet

    E-Print Network [OSTI]

    Long, David G.

    Relating Microwave Backscatter Azimuth Modulation to Surface Properties of the Greenland Ice Sheet modulation of the normalized radar cross- section in satellite data sets over Greenland is investigated. Data sastrugi are estimated. I. INTRODUCTION The Greenland ice sheet is a critical area of study in esti- mating

  3. Determination and Characterization of Ice Propagation Mechanisms on Surfaces Undergoing Dropwise Condensation

    E-Print Network [OSTI]

    Dooley, Jeffrey B.

    2011-08-08T23:59:59.000Z

    The mechanisms responsible for ice propagation on surfaces undergoing dropwise condensation have been determined and characterized. Based on experimental data acquired non-invasively with high speed quantitative microscopy, the freezing process...

  4. Interaction of acetonitrile with the surfaces of amorphous and crystalline ice

    SciTech Connect (OSTI)

    Schaff, J.E.; Roberts, J.T.

    1999-10-12T23:59:59.000Z

    The adsorption of acetonitrile (CH{sub 3}CN) on ultrathin films of ice under ultrahigh vacuum was investigated with temperature-programmed desorption ass spectrometry (TPD) and Fourier transform infrared reflection absorption spectroscopy (FTIRAS). Two types of film were studied, amorphous and crystalline. On the amorphous films, two sates of adsorbed acetonitrile were observed by TPD and FTIRAS. One of the states is attributed to acetonitrile that is hydrogen bonded to agree OH group at the ice surface; the other state is assigned to acetonitrile that is purely physiorbed. Evidence for the hydrogen-bonded state is two-fold. First, there is a large kinetic isotope effect for desorption from H{sub 2}O-and D{sub 2}O-ice: the desorption temperatures from ice-h{sub 2} and ice-d{sub 2} are {approximately}161 and {approximately}176 K, respectively. Second, the C{triple{underscore}bond}N stretching frequency (2,265 cm{sup {minus}1}) is 16 cm{sup {minus}1} is greater than that of physisorbed acetonitrile, and it is roughly equal to that of acetonitrile which is hydrogen bonded to an OH group at the air-liquid water interface. On the crystalline films, there is no evidence for a hydrogen-bonded state in the TPD spectra. The FTIRAS spectra do show that some hydrogen-bonded acetonitrile is present but at a maximum coverage that is roughly one-sixth of that on the amorphous surface. The difference between the amorphous and crystalline surfaces cannot be attributed to a difference n surface areas. Rather, this work provides additional evidence that the surface chemical properties of amorphous ice are different from those of crystalline ice.

  5. 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.

  6. Frost formation and ice adhesion on superhydrophobic surfaces

    E-Print Network [OSTI]

    Varanasi, Kripa K.

    We study frost formation and its impact on icephobic properties of superhydrophobic surfaces. Using an environmental scanning electron microscope, we show that frost nucleation occurs indiscriminately on superhydrophobic ...

  7. Surface Water Monitoring and Assessment (Ohio)

    Broader source: Energy.gov [DOE]

    This law establishes criteria for three levels of credible data for a surface water quality monitoring and assessment program and establishes the necessary training and experience for persons to...

  8. Influence of Ice Particle Surface Roughening on the Global Cloud Radiative Effect BINGQI YI,* PING YANG,* BRYAN A. BAUM,1

    E-Print Network [OSTI]

    Baum, Bryan A.

    Influence of Ice Particle Surface Roughening on the Global Cloud Radiative Effect BINGQI YI,* PING locally by more than 10 W m22 over a range of effective diameters. The global-averaged SW cloud radiative but nonnegligible increase in the global LW cloud radiative effect. 1. Introduction Ice clouds significantly

  9. Bio-inspired design of ice-retardant devices based on benthic marine invertebrates: the effect of surface texture

    E-Print Network [OSTI]

    Mehrabani, Homayun; Tse, Kyle; Evangelista, Dennis

    2014-01-01T23:59:59.000Z

    Growth of ice on surfaces poses a challenge for both organisms and for devices that come into contact with liquids below the freezing point. Resistance of some organisms to ice formation and growth, either in subtidal environments (e.g. Antarctic anchor ice), or in environments with moisture and cold air (e.g. plants, intertidal) begs examination of how this is accomplished. Several factors may be important in promoting or mitigating ice formation. As a start, here we examine the effect of surface texture alone. We tested four candidate surfaces, inspired by hard-shelled marine invertebrates and constructed using a three-dimensional printing process. We screened biological and artifical samples for ice formation and accretion in submerged conditions using previous methods, and developed a new test to examine ice formation from surface droplets as might be encountered in environments with moist, cold air. It appears surface texture plays only a small role in delaying the onset of ice formation: a stripe featur...

  10. J1.15 PARAMETERIZING THE TURBULENT SURFACE FLUXES OVER SUMMER SEA ICE Edgar L Andreas1*

    E-Print Network [OSTI]

    Persson, Ola

    1 of 9 J1.15 PARAMETERIZING THE TURBULENT SURFACE FLUXES OVER SUMMER SEA ICE Edgar L Andreas1* , P- * Corresponding author address: Edgar L Andreas, U.S. Army Cold Regions Research and Engineering Laboratory, 72

  11. Ice Nucleation on Carbon Surface Supports the Classical Theory for Heterogeneous Nucleation

    E-Print Network [OSTI]

    Cabriolu, Raffaela

    2015-01-01T23:59:59.000Z

    The prevalence of heterogeneous nucleation in nature was explained qualitatively by the classical theory for heterogeneous nucleation established over more than 60 years ago, but the quantitative validity and the key conclusions of the theory have remained unconfirmed. Employing the forward flux sampling method and the coarse-grained water model mW, we explicitly computed the heterogeneous ice nucleation rates in the supercooled water on a graphitic surface at various temperatures. The independently calculated ice nucleation rates were found to fit well according to the classical theory for heterogeneous nucleation. The fitting procedure further yields the estimate of the potency factor which measures the ratio of the heterogeneous nucleation barrier to the homogeneous nucleation barrier. Remarkably, the estimated potency factor agrees quantitatively with the volumetric ratio of the critical nuclei between the heterogeneous and homogeneous nucleation. Our numerical study thus provides a strong support to the ...

  12. Long-timescale simulations of H$_2$O admolecule diffusion on Ice Ih(0001) surfaces

    E-Print Network [OSTI]

    Pedersen, Andreas; Cuppen, Herma M; Jónsson, Hannes

    2015-01-01T23:59:59.000Z

    Long-timescale simulations of the diffusion of a H2O admolecule on the (0001) basal plane of ice Ih were carried out over a temperature range of 100 to 200 K using the adaptive kinetic Monte Carlo method and TIP4P/2005f interaction potential function. The arrangement of dangling H atoms was varied from the proton-disordered surface to the perfectly ordered Fletcher surface. A large variety of sites was found leading to a broad distribution in adsorption energy at both types of surfaces. Up to 4% of the sites have an adsorption energy exceeding the cohesive energy of ice Ih. The mean squared displacement of a simulated trajectory at 175 K for the proton-disordered surface gave a diffusion constant of 6 10$^{-10}$ cm2/s, consistent with an upper bound previously reported from experimental measurements. During the simulation, dangling H atoms were found to rearrange in order to reduce clustering, thereby approaching a linear Fletcher type arrangement. From simulations over the range in temperature, an effective ...

  13. Impact of Solvent on Photocatalytic Mechanisms: Reactions of Photodesorption Products with Ice Overlayers on the TiO2(110) Surface

    SciTech Connect (OSTI)

    Shen, Mingmin; Henderson, Michael A.

    2011-04-07T23:59:59.000Z

    The effects of water and methanol ice overlayers on the photodecomposition of acetone on rutile TiO2(110) were evaluated in ultrahigh vacuum (UHV) using photon stimulated desorption (PSD) and temperature programmed desorption (TPD). In the absence of ice overlayers, acetone photodecomposed on TiO2(110) at 95 K by ejection of a methyl radical into the gas phase and formation of acetate on the surface. With ice overlayers, the methyl radicals are trapped at the interface between TiO2(110) and the ice. When water ice was present, these trapped methyl radicals reacted either with each other to form ethane or with other molecules in the ice (e.g., water or displaced acetone) to form methane (CH4), ethane (CH3CH3) and other products (e.g., methanol), with all of these products trapped in the ice. The new products were free to revisit the surface or depart during desorption of the ice. When methanol ice was present, methane formation came about only from reaction of trapped methyl radicals with the methanol ice. Methane and ethane slowly leaked through methanol ice overlayers into vacuum at 95 K, but not through water ice overlayers. Different degrees of site competition between water and acetone, and between methanol and acetone led to different hydrogen abstraction pathways in the two ices. These results provide new insights into product formation routes and solution-phase radical formation mechanisms that are important in heterogeneous photocatalysis.

  14. An idealised experimental model of ocean surface wave transmission by an ice floe

    E-Print Network [OSTI]

    Bennetts, Luke; Meylan, Michael; Cavaliere, Claudio; Babanin, Alexander; Toffoli, Alessandro

    2015-01-01T23:59:59.000Z

    An experimental model of transmission of ocean waves by an ice floe is presented. Thin plastic plates with different material properties and thicknesses are used to model the floe. Regular incident waves with different periods and steepnesses are used, ranging from gently-sloping to storm-like conditions. A wave gauge is used to measure the water surface elevation in the lee of the floe. The depth of wave overwash on the floe is measured by a gauge in the centre of the floe's upper surface. Results show transmitted waves are regular for gently-sloping incident waves but irregular for storm-like incident waves. The proportion of the incident wave transmitted is shown to decrease as incident wave steepness increases, and to be at its minimum for an incident wavelength equal to the floe length. Further, a trend is noted for transmission to decrease as the mean wave height in the overwash region increases.

  15. IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 40, NO. 7, JULY 2002 1605 Surface Roughness Characterizations of Sea Ice and

    E-Print Network [OSTI]

    Kurapov, Alexander

    , surface roughness data from airborne laser altimeter transects correlate well with MISR-derived estimates of surface roughness. In Antarctica, ablation-related blue-ice areas, which are difficult to distinguish from bare ice exposed by crevasses, are easily detected using multiangular data. These unusual ablation

  16. Effect of atmospheric water vapor on modification of stable isotopes in near-surface snow on ice sheets

    E-Print Network [OSTI]

    Walden, Von P.

    in the near-surface snow of East Antarctica. The processes of forced ventilation, pore-space diffusion to forced ventilation for several annual cycles. Postdepositional modification during the Last Glacial. Introduction [2] Stable isotopes of water in polar snow and ice have long been regarded as proxies for local

  17. The water ice rich surface of (145453) 2005 RR43: a case for a carbon-depleted population of TNOs?

    E-Print Network [OSTI]

    N. Pinilla-Alonso; J. Licandro; R. Gil-Hutton; R. Brunetto

    2007-05-26T23:59:59.000Z

    Recent results suggest that there is a group of TNOs (2003 EL61 being the biggest member), with surfaces composed of almost pure water ice and with very similar orbital elements. We study the surface composition of another TNO that moves in a similar orbit, 2005 RR43, and compare it with the surface composition of the other members of this group. We report visible and near-infrared spectra, obtained with the 4.2m William Herschel Telescope and the 3.58m Telescopio Nazionale Galileo at the "Roque de los Muchachos" Observatory (La Palma, Spain). The spectrum of 2005 RR43 is neutral in color in the visible and dominated by very deep water ice absorption bands in the near infrared (D= 70.3 +/- 2.1 % and 82.8 +/- 4.9 % at 1.5 \\mu and 2.0 \\mu respectively). It is very similar to the spectrum of the group of TNOs already mentioned. All of them present much deeper water ice absorption bands (D>40 %) than any other TNO except Charon. Scattering models show that its surface is covered by water ice, a significant fraction in crytalline state with no trace (5 % upper limit) of complex organics. Possible scenarios to explain the existence of this population of TNOs are discussed: a giant collision, an originally carbon depleted composition, or a common process of continuous resurfacing. We conclude that TNO 2005 RR43 is member of a group, may be a population, of TNOs clustered in the space of orbital parameters that show abundant water ice and no signs of complex organics. The lack of complex organics in their surfaces suggests a significant smaller fraction of carbonaceous volatiles like CH4 in this population than in "normal" TNOs. A carbon depleted population of TNOs could be the origin of the population of carbon depleted Jupiter family comets already noticed by A'Hearn et al. (1995).

  18. Assessing the Predictability of the Beaufort Sea Minimum Ice Extent in a Changing Arctic Climate Regime

    E-Print Network [OSTI]

    Quirk, Laura Marie

    2014-04-25T23:59:59.000Z

    Understanding the climatic drivers of changes in sea ice extent in the Arctic has become increasingly important as record minima in the September sea ice extent continue to be reached. This research therefore addresses the question of which synoptic...

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

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    Antarctica (MOA) image map: Digital media, National Snow andmodel of Antarctica: Digital media, National Snow and IceThickness, 2009–2011: Digital media, NASA Distributed Active

  20. 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...

  1. Greenland ice sheet surface mass-balance modeling in a 131-year perspective, 1950-2080

    SciTech Connect (OSTI)

    Mernild, Sebastian Haugard [Los Alamos National Laboratory; Liston, Glen [COLORADO STATE UNIV.; Hiemstra, Christopher [COLORADO STATE UNIV.; Christensen, Jens [DANISH METEOROLOGICAL INS.

    2009-01-01T23:59:59.000Z

    Fluctuations in the Greenland Ice Sheet (GrIS) surface mass-balance (SMB) and freshwater influx to the surrounding oceans closely follow climate fluctuations and are of considerable importance to the global eustatic sea level rise. SnowModel, a state-of-the-art snow-evolution modeling system, was used to simulate variations in the GrIS melt extent, surface water balance components, changes in SMB, and freshwater influx to the ocean. The simulations are based on the IPCC scenario AlB modeled by the HIRHAM4 RCM (using boundary conditions from ECHAM5 AOGCM) from 1950 through 2080. In-situ meteorological station (GC-Net and WMO DMI) observations from inside and outside the GrIS were used to validate and correct RCM output data before it was used as input for SnowModel. Satellite observations and independent SMB studies were used to validate the SnowModel output and confirm the model's robustness. We simulated a {approx}90% increase in end-of-summer surface melt extent (0.483 x 10{sup 6} km{sup 2}) from 1950 to 2080, and a melt index (above 2,000-m elevation) increase of 138% (1.96 x 10{sup 6} km{sup 2} x days). The greatest difference in melt extent occured in the southern part of the GrIS, and the greatest changes in the number of melt days was seen in the eastern part of the GrIS ({approx}50-70%) and was lowest in the west ({approx}20-30%). The rate of SMB loss, largely tied to changes in ablation processes, lead to an enhanced average loss of 331 km{sup 3} from 1950 to 2080, an average 5MB level of -99 km{sup 3} for the period 2070-2080. GrIS surface freshwater runoff yielded an eustatic rise in sea level from 0.8 {+-} 0.1 (1950-1959) to 1.9 {+-} 0.1 mm (2070-2080) sea level equivalent (SLE) y{sup -1}. The accumulated GrIS freshwater runoff contribution from surface melting equaled 160 mm SLE from 1950 through 2080.

  2. Ice Mineralogy Across and Into the Surfaces of Pluto, Triton, and Eris

    E-Print Network [OSTI]

    Tegler, S C; Olkin, C B; Young, L A; Romanishin, W; Cornelison, D M; Khodadadkouchaki, R

    2012-01-01T23:59:59.000Z

    We present three near-infrared spectra of Pluto taken with the IRTF and SpeX, an optical spectrum of Triton taken with the MMT and the Red Channel Spectrograph, and previously published spectra of Pluto, Triton, and Eris. We combine these observations with a two-phase Hapke model, and gain insight into the ice mineralogy on Pluto, Triton, and Eris. Specifically, we measure the methane-nitrogen mixing ratio across and into the surfaces of these icy dwarf planets. In addition, we present a laboratory experiment that demonstrates it is essential to model methane bands in spectra of icy dwarf planets with two methane phases - one highly-diluted by nitrogen and the other rich in methane. For Pluto, we find bulk, hemisphere-averaged, methane abundances of 9.1 \\pm 0.5%, 7.1 \\pm 0.4%, and 8.2 \\pm 0.3% for sub-Earth longitudes of 10\\degree, 125\\degree, and 257\\degree. Application of the Wilcoxon rank sum test to our measurements finds these small differences are statistically significant. For Triton, we find bulk, hem...

  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. ICE MINERALOGY ACROSS AND INTO THE SURFACES OF PLUTO, TRITON, AND ERIS

    SciTech Connect (OSTI)

    Tegler, S. C. [Department of Physics and Astronomy, Northern Arizona University, Flagstaff, AZ 86011 (United States); Grundy, W. M. [Lowell Observatory, Flagstaff, AZ 86001 (United States); Olkin, C. B.; Young, L. A. [Southwest Research Institute, Boulder, CO 80302 (United States); Romanishin, W. [Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States); Cornelison, D. M. [Department of Physics, Astronomy, and Materials Science, Missouri State University, Springfield, MO 65897 (United States); Khodadadkouchaki, R., E-mail: Stephen.Tegler@nau.edu, E-mail: W.Grundy@lowell.edu, E-mail: colkin@boulder.swri.edu, E-mail: layoung@boulder.swri.edu, E-mail: wjr@nhn.ou.edu, E-mail: DavidCornelison@MissouriState.edu [Department of Physics, California State University, Northridge, CA 91330 (United States)

    2012-05-20T23:59:59.000Z

    We present three near-infrared spectra of Pluto taken with the Infrared Telescope Facility and SpeX, an optical spectrum of Triton taken with the MMT and the Red Channel Spectrograph, and previously published spectra of Pluto, Triton, and Eris. We combine these observations with a two-phase Hapke model and gain insight into the ice mineralogy on Pluto, Triton, and Eris. Specifically, we measure the methane-nitrogen mixing ratio across and into the surfaces of these icy dwarf planets. In addition, we present a laboratory experiment that demonstrates it is essential to model methane bands in spectra of icy dwarf planets with two methane phases-one highly diluted by nitrogen and the other rich in methane. For Pluto, we find bulk, hemisphere-averaged, methane abundances of 9.1% {+-} 0.5%, 7.1% {+-} 0.4%, and 8.2% {+-} 0.3% for sub-Earth longitudes of 10 Degree-Sign , 125 Degree-Sign , and 257 Degree-Sign . Application of the Wilcoxon rank sum test to our measurements finds these small differences are statistically significant. For Triton, we find bulk, hemisphere-averaged, methane abundances of 5.0% {+-} 0.1% and 5.3% {+-} 0.4% for sub-Earth longitudes of 138 Degree-Sign and 314 Degree-Sign . Application of the Wilcoxon rank sum test to our measurements finds the differences are not statistically significant. For Eris, we find a bulk, hemisphere-averaged, methane abundance of 10% {+-} 2%. Pluto, Triton, and Eris do not exhibit a trend in methane-nitrogen mixing ratio with depth into their surfaces over the few centimeter range probed by these observations. This result is contrary to the expectation that since visible light penetrates deeper into a nitrogen-rich surface than the depths from which thermal emission emerges, net radiative heating at depth would drive preferential sublimation of nitrogen leading to an increase in the methane abundance with depth.

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

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    of the Potential Sea-Level Rise from a Col- lapse of theof floating ice and sea level rise, Geophys. Res. Lett. ,contribution to sea-level rise (58 m) are simi- lar to those

  6. A New Model to Construct Ice Stream Surface Elevation Profiles and Calculate Contributions to Sea-Level Rise

    E-Print Network [OSTI]

    Adachi, Yosuke

    2012-01-01T23:59:59.000Z

    melting is responsible for, 60% comes from glaciers and ice caps.and ice caps will continue to be the dominant contributor to sea-level rise from the land ice-melting

  7. A common supersolid low-density skin sliperizing ice and toughening water surface

    E-Print Network [OSTI]

    Xi Zhang; Yongli Huang; Zengsheng Ma; Yichun Zhou; Weitao Zheng; Ji Zhou; Chang Q. Sun

    2014-08-15T23:59:59.000Z

    Skins of water and ice share the same attribute of supersolidity characterized by the identical H-O vibration frequency of 3450 cm-1. Molecular undercoordination and inter-electron-pair repulsion shortens the H-O bond and lengthen the O:H nonbond, leading to a dual process of nonbonding electron polarization. This relaxation-polarization process enhances the dipole moment, elasticity,viscosity, thermal stability of these skins with 25% density loss, which is responsible for the hydrophobicity and toughness of water skin and for the slippery of ice.

  8. 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.

  9. Assessing Phosphorous Loss to Protect Surface Water

    E-Print Network [OSTI]

    Garcia, Raul

    2005-01-01T23:59:59.000Z

    . Minimizing phosphorus pollution of surface water from agricultural fields involves manage- ment practices that control both the source and transportation factors of soil. Influences that affect the source and the amount of phosphorus transported include... the type of phosphorus applied and the content in the soil itself. Transportation factors include rainfall, irrigation, erosion, and runoff. The overall aim of environmentally sound practices is to keep soil fertility levels of phos- phorus to a range...

  10. 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

  11. An AeroCom Assessment of Black Carbon in Arctic Snow and Sea Ice

    SciTech Connect (OSTI)

    Jiao, C.; Flanner, M. G.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Berntsen, T.; Bian, Huisheng; Carslaw, K. S.; Chin, Mian; De Luca, N.; Diehl, Thomas; Ghan, Steven J.; Iversen, T.; Kirkevag, A.; Koch, Dorothy; Liu, Xiaohong; Mann, G. W.; Penner, Joyce E.; Pitari, G.; Schulz, M.; Seland, O.; Skeie, R. B.; Steenrod, Stephen D.; Stier, P.; Takemura, T.; Tsigaridis, Kostas; van Noije, T.; Yun, Yuxing; Zhang, Kai

    2014-03-07T23:59:59.000Z

    Though many global aerosols models prognose surface deposition, only a few models have been used to directly simulate the radiative effect from black carbon (BC) deposition to snow and sea-ice. Here, we apply aerosol deposition fields from 25 models contributing to two phases of the Aerosol Comparisons between Observations and Models (AeroCom) project to simulate and evaluate within snow BC concentrations and radiative effect in the Arctic. We accomplish this by driving the offline land and sea-ice components of the Community Earth System Model with different deposition fields and meteorological conditions from 2004-2009, during which an extensive field campaign of BC measurements in Arctic snow occurred. We find that models generally underestimate BC concentrations in snow in northern Russia and Norway, while overestimating BC amounts elsewhere in the Arctic. Although simulated BC distributions in snow are poorly correlated with measurements, mean values are reasonable. The multi-model mean (range) bias in BC concentrations, sampled over the same grid cells, snow depths, and months of measurements, are -4.4 (-13.2 to +10.7) ng g?1 for an earlier Phase of AeroCom models (Phase I), and +4.1 (-13.0 to +21.4) ng g?1 for a more recent Phase of AeroCom models (Phase II), compared to the observational mean of 19.2 ng g?1. Factors determining model BC concentrations in Arctic snow include Arctic BC emissions, transport of extra-Arctic aerosols, precipitation, deposition efficiency of aerosols within the Arctic, and meltwater removal of particles in snow. Sensitivity studies show that the model–measurement evaluation is only weakly affected by meltwater scavenging efficiency because most measurements were conducted in non-melting snow. The Arctic (60-90?N) atmospheric residence time for BC in Phase II models ranges from 3.7 to 23.2 days, implying large inter-model variation in local BC deposition efficiency. Combined with the fact that most Arctic BC deposition originates from extra-Arctic emissions, these results suggest that aerosol removal processes are a leading source of variation in model performance. The multi-model mean (full range) of Arctic radiative effect from BC in snow is 0.15 (0.07-0.25) W m?2 and 0.18 (0.06-0.28) W m?2 in Phase I and Phase II models, respectively. After correcting for model biases relative to observed BC concentrations in different regions of the Arctic, we obtain a multi-model mean Arctic radiative effect of 0.17 W m?2 for the combined AeroCom ensembles. Finally, there is a high correlation between modeled BC concentrations sampled over the observational sites and the Arctic as a whole, indicating that the field campaign provided a reasonable sample of the Arctic.

  12. 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

  13. Determination of Large-Scale Cloud Ice Water Concentration by Combining Surface Radar and Satellite Data in Support of ARM SCM Activities

    SciTech Connect (OSTI)

    Liu, Guosheng

    2013-03-15T23:59:59.000Z

    Single-column modeling (SCM) is one of the key elements of Atmospheric Radiation Measurement (ARM) research initiatives for the development and testing of various physical parameterizations to be used in general circulation models (GCMs). The data required for use with an SCM include observed vertical profiles of temperature, water vapor, and condensed water, as well as the large-scale vertical motion and tendencies of temperature, water vapor, and condensed water due to horizontal advection. Surface-based measurements operated at ARM sites and upper-air sounding networks supply most of the required variables for model inputs, but do not provide the horizontal advection term of condensed water. Since surface cloud radar and microwave radiometer observations at ARM sites are single-point measurements, they can provide the amount of condensed water at the location of observation sites, but not a horizontal distribution of condensed water contents. Consequently, observational data for the large-scale advection tendencies of condensed water have not been available to the ARM cloud modeling community based on surface observations alone. This lack of advection data of water condensate could cause large uncertainties in SCM simulations. Additionally, to evaluate GCMsâ�� cloud physical parameterization, we need to compare GCM results with observed cloud water amounts over a scale that is large enough to be comparable to what a GCM grid represents. To this end, the point-measurements at ARM surface sites are again not adequate. Therefore, cloud water observations over a large area are needed. The main goal of this project is to retrieve ice water contents over an area of 10 x 10 deg. surrounding the ARM sites by combining surface and satellite observations. Built on the progress made during previous ARM research, we have conducted the retrievals of 3-dimensional ice water content by combining surface radar/radiometer and satellite measurements, and have produced 3-D cloud ice water contents in support of cloud modeling activities. The approach of the study is to expand a (surface) point measurement to an (satellite) area measurement. That is, the study takes the advantage of the high quality cloud measurements (particularly cloud radar and microwave radiometer measurements) at the point of the ARM sites. We use the cloud ice water characteristics derived from the point measurement to guide/constrain a satellite retrieval algorithm, then use the satellite algorithm to derive the 3-D cloud ice water distributions within an 10�° (latitude) x 10�° (longitude) area. During the research period, we have developed, validated and improved our cloud ice water retrievals, and have produced and archived at ARM website as a PI-product of the 3-D cloud ice water contents using combined satellite high-frequency microwave and surface radar observations for SGP March 2000 IOP and TWP-ICE 2006 IOP over 10 deg. x 10 deg. area centered at ARM SGP central facility and Darwin sites. We have also worked on validation of the 3-D ice water product by CloudSat data, synergy with visible/infrared cloud ice water retrievals for better results at low ice water conditions, and created a long-term (several years) of ice water climatology in 10 x 10 deg. area of ARM SGP and TWP sites and then compared it with GCMs.

  14. 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

  15. Assessment of ISLOCA risk: Methodology and application to a Westinghouse four-loop ice condenser plant

    SciTech Connect (OSTI)

    Kelly, D.L.; Auflick, J.L.; Haney, L.N. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

    1992-04-01T23:59:59.000Z

    Inter-system loss-of-coolant accidents (ISLOCAs) have been identified as important contributors to offsite risk for some nuclear power plants. A methodology has been developed for identifying and evaluating plant-specific hardware designs, human factors issues, and accident consequence factors relevant to the estimation of ISLOCA core damage frequency and risk. This report presents a detailed description of the application of this analysis methodology to a Westinghouse four-loop ice condenser plant. This document also includes appendices A through I which provide: System descriptions; ISLOCA event trees; human reliability analysis; thermal hydraulic analysis; core uncovery timing calculations; calculation of system rupture probability; ISLOCA consequences analysis; uncertainty analysis; and component failure analysis.

  16. 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

  17. A New Model to Construct Ice Stream Surface Elevation Profiles and Calculate Contributions to Sea-Level Rise

    E-Print Network [OSTI]

    Adachi, Yosuke

    2012-01-01T23:59:59.000Z

    to 21st-Century Sea-Level Rise. Science, 321, 1340; DOI:in the Face of Sea-Level Rise: A Hybrid Modeling Approachof ice sheets to sea-level rise. Bibliography Alcamo, J. et

  18. 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...

  19. 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

  20. 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

  1. 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

  2. A LARGE ROCK AVALANCHE ONTO MORSRJKULL GLACIER, SOUTH-EAST ICELAND. ITS IMPLICATIONS FOR ICE-SURFACE EVOLUTION

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , indicating a rapid process. Photogrammetric studies of the source-area estimates the volume of the rock1 A LARGE ROCK AVALANCHE ONTO MORSÁRJÖKULL GLACIER, SOUTH-EAST ICELAND. ITS IMPLICATIONS FOR ICE, IS-600 Akureyri, Iceland Abstract In spring 2007, a large rock avalanche descended onto

  3. 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

  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. Gas Migration from Closed Coal Mines to the Surface RISK ASSESSMENT METHODOLOGY AND PREVENTION MEANS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Gas Migration from Closed Coal Mines to the Surface RISK ASSESSMENT METHODOLOGY AND PREVENTION to the surface is especially significant in the context of coal mines. This is because mine gas can migrate of the scheduled closure of all coal mining operations in France, INERIS has drawn up, at the request of national

  6. 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.

  7. 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 ...

  8. Use of OCA and APOLLO in Heliosat-4 method for the assessment of surface downwelling solar irradiance

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    the German Aerospace Center (DLR), for the assessment of surface downwelling solar irradiance (SSI). Each-based assessments of surface downwelling solar irradiance (SSI) are more and more used in the domain of solar energy, diffuse and direct surface irradiance for use in various domains: solar energy, biomass, agriculture

  9. Do et al. 1 Full Scale Tests for the Assessment of Wear of Pavement Surfaces

    E-Print Network [OSTI]

    Boyer, Edmond

    Do et al. 1 Full Scale Tests for the Assessment of Wear of Pavement Surfaces Minh-Tan Do subjected to heavy traffic. Reports can be found in (1)(2). Evolution of pavements during its whole service shown in the figure 2. By this way, during tests on one track, pavement construction can be carried out

  10. Importance of thermal effects and sea surface roughness for offshore wind resource assessment

    E-Print Network [OSTI]

    Heinemann, Detlev

    sites. The first large offshore wind farms are currently being built in several countries in EuropeImportance of thermal effects and sea surface roughness for offshore wind resource assessment National Laboratory, Roskilde, Denmark Abstract The economic feasibility of offshore wind power utilisation

  11. 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

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. 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.

  17. 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

  18. Transmission of Solar Radiation by Clouds over Snow and Ice Surfaces. Part II: Cloud Optical Depth and Shortwave Radiative Forcing from Pyranometer

    E-Print Network [OSTI]

    Warren, Stephen

    coincident hourly sea ice reports, instantaneous cloud radiative forcing and effective cloud optical depth. "Effective" optical depths (for a radiatively equivalent horizontally homogeneous cloud) are classified a characteristic optical depth of 15 at 47°S, increasing to 24 in the region of maximum cloud cover at 58°S

  19. Assessment of circuit board surface finishes for electronic assembly with lead-free solders

    SciTech Connect (OSTI)

    Ray, U.; Artaki, I.; Finley, D.W.; Wenger, G.M. [Bell Labs., Princeton, NJ (United States). Lucent Technologies; Pan, T.; Blair, H.D.; Nicholson, J.M. [Ford Motor Co., Dearborn, MI (United States); Vianco, P.T. [Sandia National Labs., Albuquerque, NM (United States)

    1996-10-01T23:59:59.000Z

    The suitability of various metallic printed wiring board surface finishes was assessed for new technology applications that incorporate assembly with Lead-free solders. The manufacture of a lead-free product necessitates elimination of lead (Pb) from the solder, the circuit board as well as the component lead termination. It is critical however for the selected interconnect Pb-free solder and the corresponding printed wiring board (PWB) and component lead finishes to be mutually compatible. Baseline compatibility of select Pb-free solders with Pb containing PWB surface finish and components was assessed. This was followed by examining the compatibility of the commercially available CASTIN{trademark} (SnAgCuSb) Pb-free solder with a series of PWB metallic finishes: Ni/Au, Ni/Pd, and Pd/Cu. The compatibility was assessed with respect to assembly performance, solder joint integrity and long term attachment reliability. Solder joint integrity and mechanical behavior of representative 50 mil pitch 20I/O SOICs was determined before and after thermal stress. Mechanical pull test studies demonstrated that the strength of SnAgCuSb solder interconnections is notably greater than that of SnPb interconnections.

  20. Assessing and Analyzing Near-Surface Radar Snow Accumulation Layers at Summit, Greenland

    E-Print Network [OSTI]

    Overly, Thomas Buckmaster

    2010-04-28T23:59:59.000Z

    depth are compared to physical properties, age-depth relationships, and accumulation rates from ice cores near Summit. Having established the radar horizons as annual accumulation markers, a 350-year record of accumulation rate is derived and analyzed...

  1. Conductivity Profile Determination by Eddy Current for Shot Peened Superalloy Surfaces Toward Residual Stress Assessment

    SciTech Connect (OSTI)

    Shen, Y.; Lo, C. C. H.; Frishman, A. M.; Lee, C.; Nakagawa, N. [Center for Nondestructive Evaluation, Iowa State University, Ames, Iowa 50011 (United States)

    2007-03-21T23:59:59.000Z

    This paper describes an eddy current model-based method for inverting near-surface conductivity deviation profiles of surface treated materials from swept-high frequency eddy current (SHFEC) data. This work forms part of our current research directed towards the development of an electromagnetic nondestructive technique for assessing residual stress of shot-peened superalloy components. The inversion procedure is based on the use of a parameterized function to describe the near-surface conductivity as a function of depth for a shot-peened surface, and the laterally uniform multi-layer theory of Cheng, Dodd and Deeds to calculate the resulting coil impedance deviations. The convergence of the inversion procedure has been tested against synthesized eddy current data. As a demonstration, the conductivity deviation profiles of a series of Inconel 718 specimens, shot peened at various Almen intensities, have been obtained by inversion. Several consistency tests were conducted to examine the reliability of the inverted conductivity profiles. The results show that conductivity deviation profiles can be reliably determined from SHFEC data within the accuracy of the current measurement system.

  2. Use of land surface remotely sensed satellite and airborne data for environmental exposure assessment in cancer research

    E-Print Network [OSTI]

    cancer and environmental contaminants, focusing primarily on agricultural chemical exposure assessmentUse of land surface remotely sensed satellite and airborne data for environmental exposure assessment in cancer research SUSAN K. MAXWELLa , JAYMIE R. MELIKERb AND PIERRE GOOVAERTSc a U.S. Geological

  3. Assessment of Heliosat-4 surface solar irradiance derived on the basis of SEVIRI-APOLLO cloud products

    E-Print Network [OSTI]

    Boyer, Edmond

    Assessment of Heliosat-4 surface solar irradiance derived on the basis of SEVIRI-APOLLO cloud are crucial for the assessment of SSI. The APOLLO cloud product provided by DLR includes abundant information about the cloud physical and optical properties. The performances of Heliosat-4 when using APOLLO

  4. 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...

  5. PROCEEDINGS OF THE 14TH INTERNATIONAL SYMPOSIUM ON ICE POTSDAM/NEWYORK/USA/27-31 JULY 1998

    E-Print Network [OSTI]

    PROCEEDINGS OF THE 14TH INTERNATIONAL SYMPOSIUM ON ICE POTSDAM/NEWYORK/USA/27-31 JULY 1998 Ice/ROTTERDAM/BROOKFIELD/ 1998 #12;Ice in Surface WatelS, Shen (ed.)@ 1998 Balkema, Rotterdam, ISBN 90 5410 971 8 Ice-on, ice-off, and ice duration for lakes and rivers with long-term records R.A.Assel & L. R. Rerche NOAA, Great Lakes

  6. Thermodynamic assessment of the variation of the surface areas of two synthetic swelling clays during adsorption of water

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Thermodynamic assessment of the variation of the surface areas of two synthetic swelling clays; Synthetic smectite; Water; Adsorption; Surface area; Swelling clay; Interlayer space #12;1. Introduction Synthetic clays are very interesting materials, both for scientific research and for industrial applications

  7. 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.

  8. Modelling Lake Volumes and Runoff on the Western Greenland Ice Sheet 

    E-Print Network [OSTI]

    Lund, Sarah

    Supra-glacial lakes can act as a key regulator of variable surface meltwater to the ice-bed interface on the Greenland Ice Sheet. In light of recent numerical studies focussing on the impact of variable surface meltwater inputs to ice sheet dynamics...

  9. In Situ, Airborne Instrumentation: Addressing and Solving Measurement Problems in Ice Clouds

    E-Print Network [OSTI]

    Cziczo, Daniel James

    A meeting of 31 international experts on in situ measurements from aircraft was held to identify unresolved questions concerning ice formation and evolution in ice clouds, assess the current state of instrumentation that ...

  10. Surfaces

    E-Print Network [OSTI]

    DeMaio, Ernest Vincent, 1964-

    1989-01-01T23:59:59.000Z

    Surfaces is a collection of four individual essays which focus on the characteristics and tactile qualities of surfaces within a variety of perceived landscapes. Each essay concentrates on a unique surface theme and purpose; ...

  11. 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.

  12. 2, 413445, 2008 Surface inversion on

    E-Print Network [OSTI]

    Boyer, Edmond

    variations in surface flow velocity and topography along a flow line on ice streams and ice sheets of spatial variations in basal topography and basal slipperiness on surface data can be accurately separatedTCD 2, 413­445, 2008 Surface inversion on ice streams G. H. Gudmundsson and M. Raymond Title Page

  13. High-Resolution Monitoring of Internal Layers Over the Greenland Ice Sheet P. Kanagaratnam, S.P. Gogineni

    E-Print Network [OSTI]

    Kansas, University of

    High-Resolution Monitoring of Internal Layers Over the Greenland Ice Sheet P. Kanagaratnam, S ice plays an important role in the rise of the Earth's sea level. A key variable in assessing the mass balance of an ice sheet is accumulation rate, which is currently determined from ice cores and pits

  14. 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.

  15. 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.

  16. Assessing surface water consumption using remotely-sensed groundwater, evapotranspiration, and precipitation

    E-Print Network [OSTI]

    Anderson, Ray G; Lo, Min-Hui; Famiglietti, James S

    2012-01-01T23:59:59.000Z

    2010), The surface water and ocean topography mission:and the Surface Energy Balance with Topography Algorithm (

  17. 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

  18. 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...

  19. Peeling back the layers: a molecular dynamics investigation into heterogeneous ice nucleation

    E-Print Network [OSTI]

    Cox, Stephen J; Slater, Ben; Michaelides, Angelos

    2015-01-01T23:59:59.000Z

    Coarse grained molecular dynamics simulations are presented in which the sensitivity of the ice nucleation rate to the hydrophilicity of a graphene nanoflake is investigated. We find that an optimal interaction strength for promoting ice nucleation exists, which coincides with that found previously for an FCC (111) surface. We further investigate the role that the layering of interfacial water plays in heterogeneous ice nucleation, and demonstrate that the extent of layering is not a good indicator of ice nucleating ability for all surfaces. Our results suggest that to be an efficient ice nucleating agent, a surface should not bind water too strongly if it is able to accommodate high coverages of water.

  20. 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...

  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. Western oil-shale development: a technology assessment. Volume 4. Solid waste from mining and surface retorts

    SciTech Connect (OSTI)

    Not Available

    1982-01-01T23:59:59.000Z

    The overall objectives of this study were to: review and evaluate published information on the disposal, composition, and leachability of solid wastes produced by aboveground shale oil extraction processes; examine the relationship of development to surface and groundwater quality in the Piceance Creek basin of northwestern Colorado; and identify key areas of research necessary to quantitative assessment of impact. Information is presented under the following section headings: proposed surface retorting developments; surface retorting processes; environmental concerns; chemical/mineralogical composition of raw and retorted oil shale; disposal procedures; water quality; and research needs.

  3. 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

  4. Variability of sea ice cover in the Chukchi Sea (western Arctic Ocean) during the Holocene

    E-Print Network [OSTI]

    Darby, Dennis

    of the Arctic Ocean during the last decades suggest a decrease in areal extent and thickness of its pack ice [e be tentatively attributed to global warming and raises concerns about the stability and fate of the pack ice of Arctic pack ice, which cannot be fully assessed from short-term instrumental observations alone

  5. 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.

  6. Access Provided by Queen's University Library at 07/21/11 2:38PM GMT The ICE Approach

    E-Print Network [OSTI]

    Graham, Nick

    Access Provided by Queen's University Library at 07/21/11 2:38PM GMT #12;The ICE Approach: Saving-Young and Robert J. Wilson, ICE is a tool for assessing student learning. The basic principles are outlined in their co-authored book, Assessment and Learning: The ICE Approach. Standing for Ideas, Connections

  7. Formation of ice lenses and frost heave A. W. Rempel1

    E-Print Network [OSTI]

    Rempel, Alan W.

    are promoted by the influence of mineral surfaces on the phase behavior of ice. A large body of experimental, but nevertheless ad hoc parameterizations for the ice particle interactions, the choice of functional form beingFormation of ice lenses and frost heave A. W. Rempel1 Received 13 April 2006; revised 26 January

  8. Feasibility study for mapping the polar ice bottom topography using interferometric synthetic-aperture

    E-Print Network [OSTI]

    Kansas, University of

    interferometric synthetic-aperture radar processing for basal surface topography mapping of the thickest GreenlandFeasibility study for mapping the polar ice bottom topography using interferometric synthetic sheets. Ice bottom topography drives ice dynamics, which affects the mass balance. Accurate information

  9. SPORT & RECREATION SERVICES-ICE HOCKEY INTRAMURALS RELEASE OF LIABILITY, WAIVER OF CLAIMS,

    E-Print Network [OSTI]

    Burg, Theresa

    of injury arising from falling and impacting against the floor or ice surface, walls or rink boardsSPORT & RECREATION SERVICES-ICE HOCKEY INTRAMURALS RELEASE OF LIABILITY, WAIVER OF CLAIMS #:______________________ TO: THE UNIVERSITY OF LETHBRIDGE (THE "UOFL"), THE ACTIVITY: The UofL plays host to Ice Hockey

  10. A NEW METHOD FOR MELT DETECTION ON ANTARCTIC ICE-SHELVES AND SCATTEROMETER CALIBRATION

    E-Print Network [OSTI]

    Long, David G.

    A NEW METHOD FOR MELT DETECTION ON ANTARCTIC ICE-SHELVES AND SCATTEROMETER CALIBRATION VERIFICATION of Engineering and Technology #12;ABSTRACT A NEW METHOD FOR MELT DETECTION ON ANTARCTIC ICE-SHELVES to determine periods of surface melt and freeze in the Antarctic ice-shelves. The normalized radar backscatter

  11. 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:...

  12. Ice Drilling Gallonmilkjugs

    E-Print Network [OSTI]

    Saffman, Mark

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

  13. 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...

  14. 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.

  15. 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.

  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. 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...

  19. 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...

  20. Molecular dynamics study of photodissociation of water in crystalline and amorphous ice

    E-Print Network [OSTI]

    Stefan Andersson; Ayman Al-Halabi; Geert-Jan Kroes; Ewine F. van Dishoeck

    2005-12-23T23:59:59.000Z

    We present results of classical dynamics calculations, performed to study the photodissociation of water in crystalline and amorphous ice surfaces at a surface temperature of 10 K. Dissociation in the top six monolayers is considered. Desorption of H2O has a low probability (less than 0.5% yield per absorbed photon) for both types of ice. The final outcome strongly depends on the original position of the photodissociated molecule. For molecules in the first bilayer of crystalline ice and the corresponding layers in amorphous ice, desorption of H atoms dominates. In the second bilayer H atom desorption, trapping of the H and OH fragments in the ice, and recombination of H and OH are of roughly equal importance. Deeper into the ice H atom desorption becomes less important and trapping and recombination dominate. The distribution of distances traveled by H atoms in the ice peaks at 6 - 7 Angstroms with a tail going to about 60 Angstroms for both types of ice. The mobility of OH radicals is low within the ice with most probable distances traveled of 2 and 1 Angstroms for crystalline and amorphous ice, respectively. OH is however quite mobile on top of the surface, where it has been found to travel more than 80 Angstroms. Simulated absorption spectra of crystalline ice, amorphous ice, and liquid water are found to be in very good agreement with experiments.

  1. 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.

  2. 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

  3. 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

  4. Spatial and temporal variability of the dimethylsulfide to chlorophyll ratio in the surface ocean: an assessment based on phytoplankton group dominance determined from space

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    po- lar front and along the pack-ice where SSTs were belowtransect at the limit of the pack-ice in mid-January (Fig.

  5. 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.

  6. Designing for effective stationkeeping in ice

    E-Print Network [OSTI]

    Nørvåg, 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

  7. Ice Nuclei in Marine Air: Biogenic Particles or Dust?

    SciTech Connect (OSTI)

    Burrows, Susannah M.; Hoose, C.; Poschl, U.; Lawrence, M.

    2013-01-11T23:59:59.000Z

    Ice nuclei impact clouds, but their sources and distribution in the atmosphere are still not well known. Particularly little attention has been paid to IN sources in marine environments, although evidence from field studies suggests that IN populations in remote marine regions may be dominated by primary biogenic particles associated with sea spray. In this exploratory model study, we aim to bring attention to this long-neglected topic and identify promising target regions for future field campaigns. We assess the likely global distribution of marine biogenic ice nuclei using a combination of historical observations, satellite data and model output. By comparing simulated marine biogenic immersion IN distributions and dust immersion IN distributions, we predict strong regional differences in the importance of marine biogenic IN relative to dust IN. Our analysis suggests that marine biogenic IN are most likely to play a dominant role in determining IN concentrations in near-surface-air over the Southern Ocean, so future field campaigns aimed at investigating marine biogenic IN should target that region. Climate related changes in the abundance and emission of biogenic marine IN could affect marine cloud properties, thereby introducing previously unconsidered feedbacks that influence the hydrological cycle and the Earth’s energy balance. Furthermore, marine biogenic IN may be an important aspect to consider in proposals for marine cloud brightening by artificial sea spray production.

  8. Evaluation of Methods to Assess and Reduce Bacterial Contamination of Surface Water from Grazing Lands

    E-Print Network [OSTI]

    Wagner, Kevin

    2012-10-19T23:59:59.000Z

    assessed the ability of alternative water supplies and grazing management to reduce E. coli loading from cattle and evaluated the ability of quantitative polymerase chain reaction analysis of total and bovine-associated Bacteroides markers (AllBac and Bo...

  9. 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.

  10. 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.

  11. 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

  12. 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

  13. Risk assessment of surface vs subsea blowout preventers (bops) on mobile offshore drilling units focusing on riser failure and the use of subsea shear rams 

    E-Print Network [OSTI]

    Melendez, Jorge Luis

    2006-08-16T23:59:59.000Z

    The use of a slim, high-pressure drilling riser for surface blowout preventer operations in the deepwater Gulf of Mexico was assessed as an alternative to conventional drilling procedures from floating units. Comparison ...

  14. 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.

  15. Modelling the impact of superimposed ice on the mass balance of an Arctic glacier under scenarios of future climate change

    E-Print Network [OSTI]

    ). A consequence of climatic warming in the high Arctic will be an increase in surface melting of glaciers and ice component of the mass accumulation of many glaciers and ice caps in thModelling the impact of superimposed ice on the mass balance of an Arctic glacier under scenarios

  16. Received 26 Aug 2013 | Accepted 22 Apr 2014 | Published 21 May 2014 Ice sheets as a significant source of highly

    E-Print Network [OSTI]

    Benning, Liane G.

    , but are rarely considered as active components of the global iron cycle. The ocean waters around both ice sheets, Katherine Lee1 & Jon Telling1 The Greenland and Antarctic Ice Sheets cover B10% of global land surface concentrations in subglacial runoff from a large Greenland Ice Sheet catchment reveal the potential for globally

  17. 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.

  18. 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...

  19. Modeling the summertime evolution of sea-ice melt ponds rsted-DTU, Electromagnetic Systems, Technical University of Denmark, Lyngby, Denmark

    E-Print Network [OSTI]

    Feltham, Daniel

    ablation. The model predictions are tested for sensitivity to the melt rate of unponded ice, enhanced melt with surface topographies derived from laser altimetry corresponding to first-year sea ice and multiyear sea ice are important in determining the total surface ablation and area covered by melt ponds. Citation

  20. 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...

  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. 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...

  3. BOREAS INTRODUCTION Fennoscandian Ice Sheet in MIS 3 Introduction

    E-Print Network [OSTI]

    Wohlfarth, Barbara

    an important re- ference for the safety assessments performed by the Swedish Nuclear Fuel and Waste Management nuclear fuel repositories. Our knowledge regarding the history of the Fennoscandian Ice Sheet during forcing mechanisms, and offers data sets that are necessary for assessing the long-term safety of spent

  4. Carbon dioxide effects research and assessment program. Environmental and societal consequences of a possible CO/sub 2/-induced climate change: volume II, part I. Response of the West Antarctic ice sheet to CO/sub 2/-induced climatic warming

    SciTech Connect (OSTI)

    Bentley, C.

    1982-04-01T23:59:59.000Z

    The paper proposes a research plan to deal with the question of what the response of the West Antarctic Ice Sheet would be to a rise in global temperatures caused by an anthropogenic CO/sub 2/ buildup in the atmosphere. The plan is designed to answer the following questions: (1) how fast is the ice mass changing now, and why; (2) how will the boundary conditions that affect the ice sheet respond to an atmospheric temperature change and how are those boundary conditions changing now; (3) what will be the response of the ice sheet to changes in boundary conditions; and (4) what can be learned by analogy with what has happened in the past. (ACR)

  5. Final Report DE-EE0005380: Assessment of Offshore Wind Farm Effects on Sea Surface, Subsurface and Airborne Electronic Systems

    SciTech Connect (OSTI)

    Ling, Hao [The University of Texas at Austin] [The University of Texas at Austin; Hamilton, Mark F. [The University of Texas at Austin Applied Research Laboratories] [The University of Texas at Austin Applied Research Laboratories; Bhalla, Rajan [Science Applications International Corporation] [Science Applications International Corporation; Brown, Walter E. [The University of Texas at Austin Applied Research Laboratories] [The University of Texas at Austin Applied Research Laboratories; Hay, Todd A. [The University of Texas at Austin Applied Research Laboratories] [The University of Texas at Austin Applied Research Laboratories; Whitelonis, Nicholas J. [The University of Texas at Austin] [The University of Texas at Austin; Yang, Shang-Te [The University of Texas at Austin] [The University of Texas at Austin; Naqvi, Aale R. [The University of Texas at Austin] [The University of Texas at Austin

    2013-09-30T23:59:59.000Z

    Offshore wind energy is a valuable resource that can provide a significant boost to the US renewable energy portfolio. A current constraint to the development of offshore wind farms is the potential for interference to be caused by large wind farms on existing electronic and acoustical equipment such as radar and sonar systems for surveillance, navigation and communications. The US Department of Energy funded this study as an objective assessment of possible interference to various types of equipment operating in the marine environment where offshore wind farms could be installed. The objective of this project was to conduct a baseline evaluation of electromagnetic and acoustical challenges to sea surface, subsurface and airborne electronic systems presented by offshore wind farms. To accomplish this goal, the following tasks were carried out: (1) survey electronic systems that can potentially be impacted by large offshore wind farms, and identify impact assessment studies and research and development activities both within and outside the US, (2) engage key stakeholders to identify their possible concerns and operating requirements, (3) conduct first-principle modeling on the interactions of electromagnetic signals with, and the radiation of underwater acoustic signals from, offshore wind farms to evaluate the effect of such interactions on electronic systems, and (4) provide impact assessments, recommend mitigation methods, prioritize future research directions, and disseminate project findings. This report provides a detailed description of the methodologies used to carry out the study, key findings of the study, and a list of recommendations derived based the findings.

  6. Assessment of structures and stabilities of defect clusters and surface energies predicted by nine interatomic potentials for UO2

    SciTech Connect (OSTI)

    Stephen A. Taller; Xian-Ming Bai

    2013-11-01T23:59:59.000Z

    The irradiation in nuclear reactors creates many point defects and defect clusters in uranium dioxide (UO2) and their evolution severely degrades the thermal and mechanical properties of the nuclear fuels. Previously many empirical interatomic potentials have been developed for modeling defect production and evolution in UO2. However, the properties of defect clusters and extended defects are usually not fitted into these potentials. In this work nine interatomic potentials for UO2 are examined by using molecular statics and molecular dynamics to assess their applicability in predicting the properties of various types of defect clusters in UO2. The binding energies and structures for these defect clusters have been evaluated for each potential. In addition, the surface energies of voids of different radii and (1 1 0) flat surfaces predicted by these potentials are also evaluated. It is found that both good agreement and significant discrepancies exist for these potentials in predicting these properties. For oxygen interstitial clusters, these potentials predict significantly different defect cluster structures and stabilities; For defect clusters consisting of both uranium and oxygen defects, the prediction is in better agreement; The surface energies predicted by these potentials have significant discrepancies, and some of them are much higher than the experimentally measured values. The results from this work can provide insight on interpreting the outcome of atomistic modeling of defect production using these potentials and may provide guidelines for choosing appropriate potential models to study problems of interest in UO2.

  7. Piezoresistive Effect for Near-Surface Eddy Current Residual Stress Assessment

    SciTech Connect (OSTI)

    Yu, F.; Nagy, P.B. [Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, Ohio 45221-0070 (United States)

    2005-04-09T23:59:59.000Z

    This paper discusses the relationship between isothermal and adiabatic piezoresistive properties of metals. The piezoresistive effect, i.e., stress-dependence of the electrical resistivity, can be exploited for nondestructive residual stress assessment using eddy current measurements. First, the paper establishes the relationship between the familiar isothermal piezoresistivity coefficients measured under uniaxial tension and hydrostatic pressure and the relevant isothermal electroelastic coefficients measured under uniaxial and biaxial stress conditions either by non-directional circular or directional elliptical eddy current coils. In order to quantitatively assess the prevailing residual stress from eddy current conductivity measurements, the electroelastic coefficients must be first determined. These calibration measurements are usually conducted on a reference specimen of the material to be tested using cyclic uniaxial loads between 0.1 and 10 Hz, which is fast enough to produce adiabatic conditions. It is demonstrated that in high-conductivity metals such calibration measurements must be corrected for the thermoelastic effect, which is always positive, i.e., it increases the conductivity in tension, when the material cools down, and reduces it in compression, when the material heats up.

  8. Blocking a wave: Frequency band gaps in ice shelves with periodic crevasses

    E-Print Network [OSTI]

    Julian Freed-Brown; Jason M. Amundson; Douglas R. MacAyeal; Wendy W. Zhang

    2011-12-14T23:59:59.000Z

    We assess how the propagation of high-frequency elastic-flexural waves through an ice shelf is modified by the presence of spatially periodic crevasses. Analysis of the normal modes supported by the ice shelf with and without crevasses reveals that a periodic crevasse distribution qualitatively changes the mechanical response. The normal modes of an ice shelf free of crevasses are evenly distributed as a function of frequency. In contrast, the normal modes of a crevasse-ridden ice shelf are distributed unevenly. There are "band gaps", frequency ranges over which no eigenmodes exist. A model ice shelf that is 50 km in lateral extent and 300 m thick with crevasses spaced 500 m apart has a band gap from 0.2 to 0.38 Hz. This is a frequency range relevant for ocean wave/ice-shelf interactions. When the outermost edge of the crevassed ice shelf is oscillated at a frequency within the band gap, the ice shelf responds very differently from a crevasse-free ice shelf. The flexural motion of the crevassed ice shelf is confined to a small region near the outermost edge of the ice shelf and effectively "blocked" from reaching the interior.

  9. SU-E-J-171: Surface Imaging Based Intrafraction Motion Assessments for Whole Brain Radiotherapy

    SciTech Connect (OSTI)

    Wiant, D; Vanderstraeten, C; Maurer, J; Pursley, J; Terrell, J; Sintay, B [Cone Health Cancer Center, Greensboro, NC (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To quantify and characterize intrafraction motion for whole brain radiotherapy treatments in open face masks using 3D surface imaging. Methods: Fifteen whole brain patients were monitored with 3D surface imaging over a total of 202 monitoring sessions. Mean translations and rotations were calculated over each minute, each session, and over all sessions combined. The percentage of each session that the root mean square (RMS) of the linear translations were outside of 2 mm, 3 mm, 4 mm, and 5 mm were determined for each patient. Correlations between mean translations per minute and time and between standard deviation per minute and time were evaluated using Pearson's r value. Results: The mean RMS translation averaged over all patients was 1.45 mm +/? 1.52 mm. The patients spent an average of 18%, 10%, 6%, and 3% of the monitoring time outside of 2 mm, 3 mm, 4 mm, and 5 mm RMS tolerances, respectively. The RMS values averaged over all patients were 1.31 mm +/? 0.98 mm, 1.52 +/- 1.04, and 1.30 mm +/? 0.71 mm over the 1th, 5th, and 10th minutes of monitoring, respectively. Neither, the RMS values (p = 0.15) or the standard deviations of the RMS values (p = 0.16) showed significant correlations with time. Conclusion: The patients were positioned within 2 mm of isocenter, which was the initial set-up tolerance, for the majority of their treatments. The average position changed by < 0.3 mm over 10 minutes of monitoring. Short term movements, reflected by the standard deviations, where on the order of 1 mm. This immobilization system provides adequate immobilization over a course of treatment for whole brain radiotherapy. This system may also be suitable for head and neck or stereotactic radiosurgery treatments as well.

  10. 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. ..

  11. 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...

  12. 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...

  13. Journal of Glaciology, Vol. 58, No. 212, 2012 doi: 10.3189/2012JoG11J249 1151 Using surface velocities to calculate ice thickness and bed

    E-Print Network [OSTI]

    Rasmussen, L.A.

    and Space Sciences, University of Washington, Seattle, WA, USA 5 School of Technology, Michigan velocities to calculate ice thickness and bed topography: a case study at Columbia Glacier, Alaska, USA R,7 W.T. PFEFFER,8 B.E. SMITH,7 M. TRUFFER1 1 Geophysical Institute, University of Alaska Fairbanks

  14. 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.

  15. 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.

  16. Electromagnetic and physical properties of sea ice formed in the presence of wave action

    E-Print Network [OSTI]

    Onstott, R. G.; Gogineni, Sivaprasad; Gow, A. J.; Grenfell, T. C.; Jezek, K. C.; Perovich, D. K.; Swift, C. T.

    1998-09-01T23:59:59.000Z

    Estimating the magnitude of brine flux to the upper ocean requires an ability to assess the dynamics of the formation of sea ice in a region. Brine storage and rate of expulsion is determined by the environmental conditions under which the sea ice...

  17. A meteorological experiment in the melting zone of the Greenland ice sheet

    SciTech Connect (OSTI)

    Oerlemans, J. (Utrecht Univ. (Netherlands)); Vugts, H.F. (Free Univ. of Amsterdam (Netherlands))

    1993-03-01T23:59:59.000Z

    Preliminary results are described from a glaciometeorological experiment carried out in the margin (melting zone) of the Greenland ice sheet in the summers of 1990 and 1991. This work was initiated within the framework of a Dutch research program on land ice and sea level change. Seven meteostations were operated along a transect running from the tundra well onto the ice sheet. At the ice edge, humidity, temperature, and wind profiles were obtained with a tethered balloon. On the ice sheet, 90 km from the edge, a boundary-layer research unit, including a sound detecting and ranging system (SODAR) and a radio acoustic sounding system (RASS), was established. Although focusing on the relation between surface energy balance, glacier mass balance, and ice flow, the experiment has also delivered a unique dataset on the dynamics of the atmospheric boundary layer around the warm tundra-cold ice sheet transition. Unexpected behavior was found for the surface albedo during the melt season. Lowest values are not found close to the ice edge, which is usual for glaciers, but higher on the ice sheet. Meltwater accumulation due to inefficient surface drainage was found to be the cause for this. The wind regime is dominated by katabatic flow from the ice sheet. The katabatic layer is typically 100-200 m thick. Close to the ice edge, the flow exhibits a very regular daily rhythm, with maximum wind speed in the afternoon. Farther on the ice sheet, the regime changes, and wind speed reaches maximum values in late night/early morning.

  18. Experimental Investigation of Direct Expansion Dynamic Ice-on-coil Storage System Used in Residential Buildings

    E-Print Network [OSTI]

    Zheng, M.; Kong, F.; Han, Z.; Liu, W.

    2006-01-01T23:59:59.000Z

    better heat exchanger ability caused by the larger surface of sheet ice, steady and low chilled water temperature was directly extracted from an ice storage tank. The longitudinal and axial fin-added coils improved the COP of the refrigerating unit...

  19. 2, 383397, 2008 Extreme surface melt

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    surface snowmelt over high elevations (above 2000 m) of the Greenland ice sheet during summer of 2007Pa atmospheric thick- ness, and the net surface energy flux, linked in turn to southerly airflow over the ice10 Scanning Multichannel Microwave Radiometer (SMMR, 1979­1987) and the Special Sensor Microwave/Imager (SSM

  20. Constraining MODIS snow albedo at large solar zenith angles: Implications for the surface energy budget in Greenland

    E-Print Network [OSTI]

    Wang, Xianwei; Zender, Charles S

    2010-01-01T23:59:59.000Z

    surface albedo of the Greenland ice sheet: satellite-derivedand J. Box. 2001. Surface climatology of the Greenland IceSheet: Greenland climate net- work 1995-1999. J. Geophys.

  1. 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

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. Conf. on Polar Meteorology and Oceanography, 9-13 Jan 2005, San Diego, CA 7.1 DETERMINING WINTERTIME HETEROGENEOUS PACK ICE CHARACTERISTICS AND

    E-Print Network [OSTI]

    Persson, Ola

    WINTERTIME HETEROGENEOUS PACK ICE CHARACTERISTICS AND THEIR IMPACT ON THE AGGREGATE ATMOSPHERIC SURFACE) over the Arctic pack ice during clear-sky wintertime conditions. These histograms were remarkable) data and a simple one- dimensional snow and ice model. The SAR data show the time of the formation

  8. Blocking a wave: Frequency band gaps in ice shelves with periodic crevasses

    E-Print Network [OSTI]

    Freed-Brown, Julian; MacAyeal, Douglas R; Zhang, Wendy W

    2011-01-01T23:59:59.000Z

    We assess how the propagation of high-frequency elastic-flexural waves through an ice shelf is modified by the presence of spatially periodic crevasses. Analysis of the normal modes supported by the ice shelf with and without crevasses reveals that a periodic crevasse distribution qualitatively changes the mechanical response. The normal modes of an ice shelf free of crevasses are evenly distributed as a function of frequency. In contrast, the normal modes of a crevasse-ridden ice shelf are distributed unevenly. There are "band gaps", frequency ranges over which no eigenmodes exist. A model ice shelf that is 50 km in lateral extent and 300 m thick with crevasses spaced 500 m apart has a band gap from 0.2 to 0.38 Hz. This is a frequency range relevant for ocean wave/ice-shelf interactions. When the outermost edge of the crevassed ice shelf is oscillated at a frequency within the band gap, the ice shelf responds very differently from a crevasse-free ice shelf. The flexural motion of the crevassed ice shelf is c...

  9. Light-absorbing Particles in Snow and Ice: Measurement and Modeling of Climatic and Hydrological Impact

    SciTech Connect (OSTI)

    Qian, Yun; Yasunari, Teppei J.; Doherty, Sarah J.; Flanner, M. G.; Lau, William K.; Ming, J.; Wang, Hailong; Wang, Mo; Warren, Stephen G.; Zhang, Rudong

    2015-01-01T23:59:59.000Z

    Light absorbing particles (LAP, e.g., black carbon, brown carbon, and dust) influence water and energy budgets of the atmosphere and snowpack in multiple ways. In addition to their effects associated with atmospheric heating by absorption of solar radiation and interactions with clouds, LAP in snow on land and ice can reduce the surface reflectance (a.k.a., surface darkening), which is likely to accelerate the snow aging process and further reduces snow albedo and increases the speed of snowpack melt. LAP in snow and ice (LAPSI) has been identified as one of major forcings affecting climate change, e.g. in the fourth and fifth assessment reports of IPCC. However, the uncertainty level in quantifying this effect remains very high. In this review paper, we document various technical methods of measuring LAPSI and review the progress made in measuring the LAPSI in Arctic, Tibetan Plateau and other mid-latitude regions. We also report the progress in modeling the mass concentrations, albedo reduction, radiative forcing, andclimatic and hydrological impact of LAPSI at global and regional scales. Finally we identify some research needs for reducing the uncertainties in the impact of LAPSI on global and regional climate and the hydrological cycle.

  10. The IceCube Collaboration: contributions to the 30th International Cosmic Ray Conference (ICRC 2007)

    E-Print Network [OSTI]

    The IceCube Collaboration

    2007-11-02T23:59:59.000Z

    This paper bundles 40 contributions by the IceCube collaboration that were submitted to the 30th International Cosmic Ray Conference ICRC 2007. The articles cover studies on cosmic rays and atmospheric neutrinos, searches for non-localized, extraterrestrial electron, muon and tau neutrino signals, scans for steady and intermittent neutrino point sources, searches for dark matter candidates, magnetic monopoles and other exotic particles, improvements in analysis techniques, as well as future detector extensions. The IceCube observatory will be finalized in 2011 to form a cubic-kilometer ice-Cherenkov detector at the location of the geographic South Pole. At the present state of construction, IceCube consists of 52 paired IceTop surface tanks and 22 IceCube strings with a total of 1426 Digital Optical Modules deployed at depths up to 2350 m. The observatory also integrates the 19 string AMANDA subdetector, that was completed in 2000 and extends IceCube's reach to lower energies. Before the deployment of IceTop, cosmic air showers were registered with the 30 station SPASE-2 surface array. IceCube's low noise Digital Optical Modules are very reliable, show a uniform response and record waveforms of arriving photons that are resolvable with nanosecond precision over a large dynamic range. Data acquisition, reconstruction and simulation software are running in production mode and the analyses, profiting from the improved data quality and increased overall sensitivity, are well under way.

  11. Development of an ultrasonic pulse-echo (UPE) technique for aircraft icing studies

    SciTech Connect (OSTI)

    Liu, Yang; Hu, Hui [Department of Aerospace Engineering, Iowa State University, 2271 Howe Hall, Room 1200, Ames, IA 50011 (United States); Chen, Wen-Li [Department of Aerospace Engineering, Iowa State University, 2271 Howe Hall, Room 1200, Ames, IA 50011 (United States); School of Civil Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150090 (China); Bond, Leonard J. [Department of Aerospace Engineering, Iowa State University, 2271 Howe Hall, Room 1200, Ames, IA 50011 (United States); Center for Nondestructive Evaluation, Iowa State University, 1915 Scholl Road, 151 ASC II, Ames, IA 50011 (United States)

    2014-02-18T23:59:59.000Z

    Aircraft operating in some cold weather conditions face the risk of icing. Icing poses a threat to flight safety and its management is expensive. Removing light frost on a clear day from a medium-size business jet can cost $300, heavy wet snow removal can cost $3,000 and removal of accumulated frozen/freezing rain can cost close to $10,000. Understanding conditions that lead to severe icing events is important and challenging. When an aircraft or rotorcraft flies in a cold climate, some of the super cooled droplets impinging on exposed aircraft surfaces may flow along the surface prior to freezing and give various forms and shapes of ice. The runback behavior of a water film on an aircraft affects the morphology of ice accretion and the rate of formation. In this study, we report the recent progress to develop an Ultrasonic Pulse-Echo (UPE) technique to provide real-time thickness distribution measurements of surface water flows driven by boundary layer airflows for aircraft icing studies. A series of initial experimental investigations are conducted in an ice wind tunnel employing an array of ultrasonic transducers placed underneath the surface of a flat plate. The water runback behavior on the plate is evaluated by measuring the thickness profile variation of the water film along the surface by using the UPE technique under various wind speed and flow rate conditions.

  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. IceCube Project Monthly Report September 2007

    E-Print Network [OSTI]

    Saffman, Mark

    planned. The additional hubs will be are spares. The new release of DAQ software, including over 100 new for glacial motion, and the other one using the IceCube Standard Candle that provides an absolute energy-Plan AnnualBaseline Re-Plan Instrumentation Re-Plan for 75+ Str. #12;3 Risk Assessment & Potential Contingency

  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. Fluid Migration During Ice/Rock Planetesimal Differentiation

    E-Print Network [OSTI]

    Raney, Robert 1987-

    2012-12-12T23:59:59.000Z

    /water reaction, which will depend on the rate at which water can be segregated from a melting ice/rock core. For the liquid water phase to migrate toward the surface, the denser rock phase must compact. The primary question that this thesis will answer is how...

  3. Intelligent Matchmaking for Polar Ice Sheet Data Collection and Delivery

    E-Print Network [OSTI]

    Kansas, University of

    of intelligent radars integrated into robotic vehicles. They autonomously decide where and how to measure to map near- surface layers. These sensors are integrated into two vehicles; an autonomous robotic Abstract-- The PRISM (Polar Radar for Ice Sheet Measurement) project is developing mobile, autonomous

  4. II. Properties of Water 1. Ice and Liquid water structure

    E-Print Network [OSTI]

    Frey, Terry

    Heat Capacity 4. Solvent Properties 5. Dissociation: Acids & Bases / pH II. Organic Chemistry A transport in plants #12;Water has a high specific heat capacity specific heat capacity = amount of energyII. Properties of Water 1. Ice and Liquid water structure 2. Cohesion / Surface Tension 3. High

  5. 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

  6. 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

  7. 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.

  8. Water Ice in 2060 Chiron and its Implications for Centaurs and Kuiper Belt Objects

    E-Print Network [OSTI]

    J. X. Luu; D. C. Jewitt; C. Trujillo

    2000-02-04T23:59:59.000Z

    We report the detection of water ice in the Centaur 2060 Chiron, based on near-infrared spectra (1.0 - 2.5 micron) taken with the 3.8-meter United Kingdom Infrared Telescope (UKIRT) and the 10-meter Keck Telescope. The appearance of this ice is correlated with the recent decline in Chiron's cometary activity: the decrease in the coma cross-section allows previously hidden solid-state surface features to be seen. We predict that water ice is ubiquitous among Centaurs and Kuiper Belt objects, but its surface coverage varies from object to object, and thus determines its detectability and the occurrence of cometary activity.

  9. The Design and Performance of IceCube DeepCore

    E-Print Network [OSTI]

    The IceCube Collaboration

    2011-09-25T23:59:59.000Z

    The IceCube neutrino observatory in operation at the South Pole, Antarctica, comprises three distinct components: a large buried array for ultrahigh energy neutrino detection, a surface air shower array, and a new buried component called DeepCore. DeepCore was designed to lower the IceCube neutrino energy threshold by over an order of magnitude, to energies as low as about 10 GeV. DeepCore is situated primarily 2100 m below the surface of the icecap at the South Pole, at the bottom center of the existing IceCube array, and began taking physics data in May 2010. Its location takes advantage of the exceptionally clear ice at those depths and allows it to use the surrounding IceCube detector as a highly efficient active veto against the principal background of downward-going muons produced in cosmic-ray air showers. DeepCore has a module density roughly five times higher than that of the standard IceCube array, and uses photomultiplier tubes with a new photocathode featuring a quantum efficiency about 35% higher than standard IceCube PMTs. Taken together, these features of DeepCore will increase IceCube's sensitivity to neutrinos from WIMP dark matter annihilations, atmospheric neutrino oscillations, galactic supernova neutrinos, and point sources of neutrinos in the northern and southern skies. In this paper we describe the design and initial performance of DeepCore.

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. IceCube: Construction Status and First Results

    E-Print Network [OSTI]

    Albrecht Karle; for the IceCube Collaboration

    2008-12-20T23:59:59.000Z

    IceCube is a 1 km3 neutrino telescope currently under construction at the South Pole. The detector will consist of 4800 optical sensors deployed at depths between 1450 m and 2450 m in clear Antarctic ice evenly distributed over 80 strings. An air shower array covering a surface area of 1 km^2 above the in-ice detector will measure cosmic ray air showers in the energy range from 300 TeV to above 1 EeV. The detector is designed to detect neutrinos of all flavors. With 40 strings currently in operation, construction is 50% complete. Based on data taken to date, the observatory meets its design goals and currently exceeds the sensitivity of AMANDA and previous neutrino telescopes. The construction outlook and possible future extensions are also discussed.

  20. 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

  1. 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; ...

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. The shallow shelf approximation as a "sliding law" in a thermomechanically coupled ice sheet model

    E-Print Network [OSTI]

    Bueler, Ed

    2008-01-01T23:59:59.000Z

    The shallow shelf approximation is a better ``sliding law'' for ice sheet modeling than those sliding laws in which basal velocity is a function of driving stress. The shallow shelf approximation as formulated by \\emph{Schoof} [2006a] is well-suited to this use. Our new thermomechanically coupled sliding scheme is based on a plasticity assumption about the strength of the saturated till underlying the ice sheet in which the till yield stress is given by a Mohr-Coulomb formula using a modeled pore water pressure. Using this scheme, our prognostic whole ice sheet model has convincing ice streams. Driving stress is balanced in part by membrane stresses, the model is computable at high spatial resolution in parallel, it is stable with respect to parameter changes, and it produces surface velocities seen in actual ice streams.

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. Towards a tool to design vegetated strips for mitigation of pesticides transfers in surface runoff. Assessment of different

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    (Simunek et al,1999) coupled with a kinematic wave equation, which represents both surface runoff pollutions. Water pollution control division. Cemagref. 3 Bis Quai Chauveau. 69 336 LYON 09. France. * nadia fields towards surface waters. However, as the efficiency of these structures is closely related

  14. The IceCube Collaboration:contributions to the 30 th International Cosmic Ray Conference (ICRC 2007),

    SciTech Connect (OSTI)

    IceCube Collaboration; Ackermann, M.

    2007-11-02T23:59:59.000Z

    This paper bundles 40 contributions by the IceCube collaboration that were submitted to the 30th International Cosmic Ray Conference ICRC 2007. The articles cover studies on cosmic rays and atmospheric neutrinos, searches for non-localized, extraterrestrial {nu}{sub e}, {nu}{sub {mu}} and {nu}{sub {tau}} signals, scans for steady and intermittent neutrino point sources, searches for dark matter candidates, magnetic monopoles and other exotic particles, improvements in analysis techniques, as well as future detector extensions. The IceCube observatory will be finalized in 2011 to form a cubic-kilometer ice-Cherenkov detector at the location of the geographic South Pole. At the present state of construction, IceCube consists of 52 paired IceTop surface tanks and 22 IceCube strings with a total of 1426 Digital Optical Modules deployed at depths up to 2350 m. The observatory also integrates the 19 string AMANDA subdetector, that was completed in 2000 and extends IceCube's reach to lower energies. Before the deployment of IceTop, cosmic air showers were registered with the 30 station SPASE-2 surface array. IceCube's low noise Digital Optical Modules are very reliable, show a uniform response and record waveforms of arriving photons that are resolvable with nanosecond precision over a large dynamic range. Data acquisition, reconstruction and simulation software are running in production mode and the analyses, profiting from the improved data quality and increased overall sensitivity, are well under way.

  15. Journal of Nondestructive Evaluation, Vol. 23, No. 3, September 2004 ( C 2004) Eddy Current Assessment of Near-Surface Residual

    E-Print Network [OSTI]

    Nagy, Peter B.

    Journal of Nondestructive Evaluation, Vol. 23, No. 3, September 2004 ( C 2004) Eddy Current in eddy current conductivity at increasing inspection frequencies, which can be exploited components, lend themselves easily for eddy current residual stress assessment lies in their favorable

  16. Assessment of clear and cloudy sky parameterizations for daily downwelling longwave radiation over different land surfaces in

    E-Print Network [OSTI]

    meteorological data, resulting in reliable quantification of net radiation and evapotranspiration in FloridaAssessment of clear and cloudy sky parameterizations for daily downwelling longwave radiation over sky downwelling longwave radiation (Rldc) and cloudy sky downwelling longwave radiation (Rld) formulas

  17. Indirect ultraviolet photodesorption from CO:N2 binary ices - an efficient grain-gas process

    E-Print Network [OSTI]

    Bertin, Mathieu; Romanzin, Claire; Poderoso, Hugo A M; Michaut, Xavier; Philippe, Laurent; Jeseck, Pascal; Öberg, Karin I; Linnartz, Harold; Fillion, Jean-Hugues

    2013-01-01T23:59:59.000Z

    UV ice photodesorption is an important non-thermal desorption pathway in many interstellar environments that has been invoked to explain observations of cold molecules in disks, clouds and cloud cores. Systematic laboratory studies of the photodesorption rates, between 7 and 14 eV, from CO:N2 binary ices, have been performed at the DESIRS vacuum UV beamline of the synchrotron facility SOLEIL. The photodesorption spectral analysis demonstrates that the photodesorption process is indirect, i.e. the desorption is induced by a photon absorption in sub-surface molecular layers, while only surface molecules are actually desorbing. The photodesorption spectra of CO and N2 in binary ices therefore depend on the absorption spectra of the dominant species in the subsurface ice layer, which implies that the photodesorption efficiency and energy dependence are dramatically different for mixed and layered ices compared to pure ices. In particular, a thin (1-2 ML) N2 ice layer on top of CO will effectively quench CO photod...

  18. The Formation of Ice Giants in a Packed Oligarchy: Instability and Aftermath

    E-Print Network [OSTI]

    Ford, E B; Ford, Eric B.; Chiang, Eugene

    2007-01-01T23:59:59.000Z

    As many as 5 ice giants--Neptune-mass planets composed of 90% ice and rock and 10% hydrogen--are thought to form at heliocentric distances of 10-25 AU on closely packed orbits spaced ~5 Hill radii apart. Such oligarchies are ultimately unstable. Once the parent disk of planetesimals is sufficiently depleted, oligarchs perturb one another onto crossing orbits. We explore both the onset and the outcome of the instability through numerical integrations, including dynamical friction cooling of planets by a planetesimal disk whose properties are held fixed. To trigger instability and the ejection of the first ice giant in systems having an original surface density in oligarchs of Sigma ~ 1 g/cm^2, the disk surface density s must fall below 0.1 g/cm^2. Ejections are predominantly by Jupiter and occur within 10 Myr. To eject more than 1 oligarch requires s ice ...

  19. 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.

  20. 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

  1. Molecular interactions with ice: Molecular embedding, adsorption, detection, and release

    SciTech Connect (OSTI)

    Gibson, K. D.; Langlois, Grant G.; Li, Wenxin; Sibener, S. J., E-mail: s-sibener@uchicago.edu [The James Franck Institute and Department of Chemistry, The University of Chicago, 929 E. 57th Street, Chicago, Illinois 60637 (United States); Killelea, Daniel R. [Department of Chemistry and Biochemistry, Loyola University Chicago, 1068 W. Sheridan Ave., Chicago, Illinois 60660 (United States)

    2014-11-14T23:59:59.000Z

    The interaction of atomic and molecular species with water and ice is of fundamental importance for chemistry. In a previous series of publications, we demonstrated that translational energy activates the embedding of Xe and Kr atoms in the near surface region of ice surfaces. In this paper, we show that inert molecular species may be absorbed in a similar fashion. We also revisit Xe embedding, and further probe the nature of the absorption into the selvedge. CF{sub 4} molecules with high translational energies (?3 eV) were observed to embed in amorphous solid water. Just as with Xe, the initial adsorption rate is strongly activated by translational energy, but the CF{sub 4} embedding probability is much less than for Xe. In addition, a larger molecule, SF{sub 6}, did not embed at the same translational energies that both CF{sub 4} and Xe embedded. The embedding rate for a given energy thus goes in the order Xe > CF{sub 4} > SF{sub 6}. We do not have as much data for Kr, but it appears to have a rate that is between that of Xe and CF{sub 4}. Tentatively, this order suggests that for Xe and CF{sub 4}, which have similar van der Waals radii, the momentum is the key factor in determining whether the incident atom or molecule can penetrate deeply enough below the surface to embed. The more massive SF{sub 6} molecule also has a larger van der Waals radius, which appears to prevent it from stably embedding in the selvedge. We also determined that the maximum depth of embedding is less than the equivalent of four layers of hexagonal ice, while some of the atoms just below the ice surface can escape before ice desorption begins. These results show that energetic ballistic embedding in ice is a general phenomenon, and represents a significant new channel by which incident species can be trapped under conditions where they would otherwise not be bound stably as surface adsorbates. These findings have implications for many fields including environmental science, trace gas collection and release, and the chemical composition of astrophysical icy bodies in space.

  2. 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.

  3. Water Ice on the Satellite of Kuiper Belt Object 2003 EL61

    E-Print Network [OSTI]

    K. M Barkume; M. E. Brown; E. L. Schaller

    2006-01-24T23:59:59.000Z

    We have obtained a near infrared spectrum of the brightest satellite of the large Kuiper Belt Object, 2003 EL61. The spectrum has absorption features at 1.5 and 2.0 microns, indicating that water ice is present on the surface. We find that the satellite's absorption lines are much deeper than water ice features typically found on Kuiper Belt Objects. We argue that the unusual spectrum indicates that the satellite was likely formed by impact and not by capture.

  4. 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.

  5. First-Principles Assessment of H[subscript 2]S and H[subscript 2]O Reaction Mechanisms and the Subsequent Hydrogen Absorption on the CeO[subscript 2](111) Surface

    E-Print Network [OSTI]

    Marrocchelli, Dario

    The main goal of this study is to assess the resistance of ceria against hydrogen penetration into its bulk, in the context of its application as a protective surface coating against hydrogen embrittlement in metals. We ...

  6. 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 ...

  7. 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...

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. On the applicability of the Heliosat-2 method to assess surface solar irradiance in the Intertropical Convergence Zone,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    on the Earth's surface and its geographical distribution is of prime importance for numerous solar-3027" DOI : 10.1080/01431161.2012.756598 #12;2 energy systems for heating and electrical power generation satisfactory for Europe, including Madeira Island (Aculinin 2008; Blanc et al. 2011; Lefèvre et al. 2007

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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...

  1. 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

  2. On the Nanoengineering of Superhydrophobic and Impalement Resistant Surface Textures below the Freezing Temperature

    E-Print Network [OSTI]

    Daraio, Chiara

    On the Nanoengineering of Superhydrophobic and Impalement Resistant Surface Textures below: The superhydrophobic behavior of nano- and microtextured surfaces leading to rebound of impacting droplets is of great morphology, superhydrophobicity, supercooling, anti-icing, drop impact Nanotextured surfaces in nature

  3. Calibration and Characterization of the IceCube Photomultiplier Tube

    SciTech Connect (OSTI)

    IceCube Collaboration; Abbasi, R.; al., et

    2010-02-11T23:59:59.000Z

    Over 5,000 PMTs are being deployed at the South Pole to compose the IceCube neutrino observatory. Many are placed deep in the ice to detect Cherenkov light emitted by the products of high-energy neutrino interactions, and others are frozen into tanks on the surface to detect particles from atmospheric cosmic ray showers. IceCube is using the 10-inch diameter R7081-02 made by Hamamatsu Photonics. This paper describes the laboratory characterization and calibration of these PMTs before deployment. PMTs were illuminated with pulses ranging from single photons to saturation level. Parameterizations are given for the single photoelectron charge spectrum and the saturation behavior. Time resolution, late pulses and afterpulses are characterized. Because the PMTs are relatively large, the cathode sensitivity uniformity was measured. The absolute photon detection efficiency was calibrated using Rayleigh-scattered photons from a nitrogen laser. Measured characteristics are discussed in the context of their relevance to IceCube event reconstruction and simulation efforts.

  4. 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.

  5. 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 ...

  6. Environmental Assessment

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

    surface and the lower part of the atmosphere; this phenomenon is called the greenhouse effect. U.S. Department of Energy DOEEA-1728D Draft Environmental Assessment 32 June...

  7. arXiv:1408.2487v2[physics.ao-ph]22Aug2014 Ising model for melt ponds on Arctic sea ice

    E-Print Network [OSTI]

    Golden, Kenneth M.

    arXiv:1408.2487v2[physics.ao-ph]22Aug2014 Ising model for melt ponds on Arctic sea ice Yi-Ping Ma,1, USA The albedo of melting Arctic sea ice, a key parameter in climate modeling, is determined by pools of water on the ice surface. Recent observations show an onset of pond complexity at a critical area

  8. 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...

  9. 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...

  10. 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

  11. Scaling relation for the bond length, mass density, and packing order of water ice

    E-Print Network [OSTI]

    Sun, Chang Q

    2013-01-01T23:59:59.000Z

    The packing order of molecules and the distance between adjacent oxygen atoms (dOO) in water and ice are most basic yet puzzling. Here we present a scaling solution for this purpose based only on the mass density (gcm-3), (Equation) where dL is the length ({\\AA}) of the O:H van der Waals bond and dH the H-O polar-covalent bond projecting on the O---O line. Validated by the measured proton symmetrization of compressed ice, dOO of water and ice, and dOO expansion at water surface, this solution confirms that the fluctuated, tetrahedrally-coordinated structure is unique for water ice.

  12. Scaling relation for the bond length, mass density, and packing order of water ice

    E-Print Network [OSTI]

    Chang Q Sun

    2013-05-18T23:59:59.000Z

    The packing order of molecules and the distance between adjacent oxygen atoms (dOO) in water and ice are most basic yet puzzling. Here we present a scaling solution for this purpose based only on the mass density (gcm-3), (Equation) where dL is the length ({\\AA}) of the O:H van der Waals bond and dH the H-O polar-covalent bond projecting on the O---O line. Validated by the measured proton symmetrization of compressed ice, dOO of water and ice, and dOO expansion at water surface, this solution confirms that the fluctuated, tetrahedrally-coordinated structure is unique for water ice.

  13. 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...

  14. Can xenon in water inhibit ice growth? Molecular dynamics of phase transitions in water$-$Xe system

    E-Print Network [OSTI]

    Vasilii I. Artyukhov; Alexander Yu. Pulver; Alex Peregudov; Igor Artyuhov

    2014-07-11T23:59:59.000Z

    Motivated by recent experiments showing the promise of noble gases as cryoprotectants, we perform molecular dynamics modeling of phase transitions in water with xenon under cooling. We study the structure and dynamics of xenon water solution as a function of temperature. Homogeneous nucleation of clathrate hydrate phase is observed and characterized. As the temperature is further reduced we observe hints of dissociation of clathrate due to stronger hydrophobic hydration, pointing towards a possible instability of clathrate at cryogenic temperatures and conversion to an amorphous phase comprised of "xenon + hydration shell" Xe$\\cdot$(H$_{2}$O)$_{21.5}$ clusters. Simulations of ice$-$xenon solution interface in equilibrium and during ice growth reveal the effects of xenon on the ice$-$liquid interface, where adsorbed xenon causes roughening of ice surface but does not preferentially form clathrate. These results provide evidence against the ice-blocker mechanism of xenon cryoprotection.

  15. Further observations of a decreasing atmospheric CO2 uptake capacity in the Canada Basin (Arctic Ocean) due to sea ice loss

    E-Print Network [OSTI]

    Boyer, Edmond

    decayed ice cover, we found surprisingly high pCO2sw (~290­320 matm), considering that surface waterFurther observations of a decreasing atmospheric CO2 uptake capacity in the Canada Basin (Arctic as an atmospheric CO2 sink under the summertime ice-free conditions expected in the near future. Beneath a heavily

  16. Direct releases to the surface and associated complementary cumulative distribution functions in the 1996 performance assessments for the Waste Isolation Pilot Plant: Direct brine release

    SciTech Connect (OSTI)

    STOELZEL,D.M.; O'BRIEN,D.G.; GARNER,J.W.; HELTON,JON CRAIG; JOHNSON,J.D.; SCOTT,L.N.

    2000-05-19T23:59:59.000Z

    The following topics related to the treatment of direct brine releases to the surface environment in the 1996 performance assessment for the Waste Isolation Pilot Plant (WIPP) are presented (1) mathematical description of models, (2) uncertainty and sensitivity analysis results arising from subjective (i.e., epistemic) uncertainty for individual releases, (3) construction of complementary cumulative distribution functions (CCDFs) arising from stochastic (i.e., aleatory) uncertainty, and (4) uncertainty and sensitivity analysis results for CCDFs. The presented analyses indicate that direct brine releases do not constitute a serious threat to the effectiveness of the WIPP as a disposal facility for transuranic waste. Even when the effects of uncertain analysis inputs are taken into account, the CCDFs for direct brine releases fall substantially to the left of the boundary line specified in the US Environmental Protection Agency's standard for the geologic disposal of radioactive waste (4O CFR 191.40 CFR 194).

  17. 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.

  18. 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

  19. 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

  20. 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.

  1. 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.

  2. 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

  3. Predicting Land-Ice Retreat and Sea-Level Rise with the Community Earth System Model

    SciTech Connect (OSTI)

    Lipscomb, William [Los Alamos National Laboratory

    2012-06-19T23:59:59.000Z

    Coastal stakeholders need defensible predictions of 21st century sea-level rise (SLR). IPCC assessments suggest 21st century SLR of {approx}0.5 m under aggressive emission scenarios. Semi-empirical models project SLR of {approx}1 m or more by 2100. Although some sea-level contributions are fairly well constrained by models, others are highly uncertain. Recent studies suggest a potential large contribution ({approx}0.5 m/century) from the marine-based West Antarctic Ice Sheet, linked to changes in Southern Ocean wind stress. To assess the likelihood of fast retreat of marine ice sheets, we need coupled ice-sheet/ocean models that do not yet exist (but are well under way). CESM is uniquely positioned to provide integrated, physics based sea-level predictions.

  4. 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

  5. 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

  6. 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...

  7. 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.

  8. 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...

  9. 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...

  10. 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

  11. 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

  12. 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...

  13. 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,

  14. 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...

  15. 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

  16. Amundsen Sea sea-ice variability, atmospheric circulation, and spatial variations in snow isotopic composition from new West Antarctic firn cores

    E-Print Network [OSTI]

    Criscitiello, Alison Sara

    2014-01-01T23:59:59.000Z

    Recent work has documented dramatic changes in the West Antarctic Ice Sheet (WAIS) over the past 30 years (e.g., mass loss, glacier acceleration, surface warming) due largely to the influence of the marine environment. ...

  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. 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.

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. Low-Frequency Electrical Properties of Ice-Silicate Mixtures David E. Stillman,*,

    E-Print Network [OSTI]

    Stillman, David E.

    Low-Frequency Electrical Properties of Ice-Silicate Mixtures David E. Stillman,*, Robert E. Grimm The low-frequency electrical properties of mixtures of silicates and saline H2O were measured over broad are able to form in proximity to silicate surfaces. Five dielectric relaxations related to H2O were

  9. 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.

  10. 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

  11. 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.

  12. 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...

  13. 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.

  14. Effects of exchange bias on magnetotransport in permalloy kagome artificial spin ice

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Le, B. L.; Rench, D. W.; Misra, R.; O’Brien, L.; Leighton, C.; Samarth, N.; Schiffer, P.

    2015-02-01T23:59:59.000Z

    We investigate the magnetotransport properties of connected kagome artificial spin ice networks composed of permalloy nanowires. Our data show clear evidence of magnetic switching among the wires, both in the longitudinal and transverse magnetoresistance. An unusual asymmetry with field sweep direction appears at temperatures below about 20 K that appears to be associated with exchange bias resulting from surface oxidation of permalloy, and which disappears in alumina-capped samples. These results demonstrate that exchange bias is a phenomenon that must be considered in understanding the physics of such artificial spin ice systems, and that opens up new possibilities for their control.

  15. Laboratory investigations of irradiated acetonitrile-containing ices on an interstellar dust analog

    SciTech Connect (OSTI)

    Abdulgalil, Ali G. M.; Marchione, Demian; Rosu-Finsen, Alexander; Collings, Mark P.; McCoustra, Martin R. S. [School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton, Edinburgh, EH14 4AS (United Kingdom)

    2012-07-15T23:59:59.000Z

    Reflection-absorption infrared spectroscopy is used to study the impact of low-energy electron irradiation of acetonitrile-containing ices, under conditions close to those in the dense star-forming regions in the interstellar medium. Both the incident electron energy and the surface coverage were varied. The experiments reveal that solid acetonitrile is desorbed from its ultrathin solid films with a cross section of the order of 10{sup -17} cm{sup 2}. Evidence is presented for a significantly larger desorption cross section for acetonitrile molecules at the water-ice interface, similar to that previously observed for the benzene-water system.

  16. JOURNAL OF GEOPHYSICAL RESEARCH, VOL 104, NO C7, PAGES 15,66915,677, JULY 15, 1999 An energyconserving thermodynamic model of sea ice

    E-Print Network [OSTI]

    Bitz, Cecilia

    of internal brine­pocket melting on surface ablation. Sea ice models that parameterize latent heat storage in brine pockets often fail to reduce the energy required for surface ablation in proportion leads to reduced heat conduction, less internal brine­pocket melting, and more surface ablation. 1

  17. 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.

  18. 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.

  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. 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

  2. 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

  3. 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.

  4. In Situ Airborne Instrumentation: Addressing and Solving Measurement Problems in Ice Clouds

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baumgardner, Darrel; Kok, Greg; Avallone, L.; Bansemer, A.; Borrmann, S.; Brown, P.; Bundke, U.; Chuang, P. Y.; Cziczo, D.; Field, P.; et al

    2012-02-01T23:59:59.000Z

    A meeting of 31 international experts on in situ measurements from aircraft was held to identify unresolved questions concerning ice formation and evolution in ice clouds, assess the current state of instrumentation that can address these problems, introduce emerging technology that may overcome current measurement issues and recommend future courses of action that can improve our understanding of ice cloud microphysical processes and their impact on the environment. The meeting proceedings and outcome has been described in detail in a manuscript submitted to the Bulletin of the American Meteorological Society (BAMS) on March 24, 2011. This paper is currently undermore »review. The remainder of this summary, in the following pages, is the text of the BAMS article. A technical note that will be published by the National Center for Atmospheric Research is currently underway and is expected to be published before the end of the year.« less

  5. In Situ Airborne Instrumentation: Addressing and Solving Measurement Problems in Ice Clouds

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baumgardner, Darrel [Univ. Nacional Autonoma de Mexico, Mexico City (Mexico). Centro de Ciencias de la Atmosfera; Kok, Greg [Univ. Nacional Autonoma de Mexico, Mexico City (Mexico). Centro de Ciencias de la Atmosfera; Avallone, L. [Univ. of Colorado, Boulder, CO (United States); Bansemer, A. [National Center for Atmospheric Research, Boulder, CO (United States); Borrmann, S. [Univ. of Maine (Germany); Brown, P. [Met Office, Exeter (United Kingdom); Bundke, U. [Univ. of Frankfurt (Germany); Chuang, P. Y. [Univ. of California, Santa Cruz, CA (United States); Cziczo, D. [Massachusetts Institute of Technology, Cambridge, MA (United States); Field, P. [Met Office, Exeter (United Kingdom); Gallagher, M. [Univ. of Manchester (United Kingdom); Gayet, J. -F. [CNRS/Univ. Blaise Pascal, Clermont-Ferrand (France). Lab. de Meteorologie Physique; Heymsfield, A. [National Center for Atmospheric Research, Boulder, CO (United States); Korolev, A. [Environment Canada (Canada). Cloud Physics and Severe Weather Research Section; Kraemer, M. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Energie- und Klimaforschung Stratosphaere; McFarquhar, G. [Univ. of Illinois at Urbana-Champaign, IL (United States); Mertes, S. [Leibniz Inst. for Tropospheric Research, Leipzig (Germany); Moehler, O. [Karlsruhe Institute of Technology (Germany); Lance, S. [Univ. of Colorado, Boulder, CO (United States). Cooperative Inst. for Research in Environmental Sciences, Climate Diagnostics Center; National Oceanic and Atmospheric Administration, Boulder, CO (United States); Lawson, P. [SPEC, Inc., Boulder, CO (United States); Petters, M. D. [North Carolina State Univ., Raleigh, NC (United States); Pratt, K. [Purdue Univ., West Lafayette, IN (United States); Roberts, G. [Scripps Oceanographic Inst., La Jolla, CA (United States); Rogers, D. [National Center for Atmospheric Research, Boulder, CO (United States); Stetzer, O. [ETH, Zurich (Switzerland). Inst. for Atmospheric and Climate Science; Stith, J. [National Center for Atmospheric Research, Boulder, CO (United States); Strapp, W. [Environment Canada (Canada). Cloud Physics and Severe Weather Research Section; Twohy, C. [Oregon State Univ., Corvallis, OR (United States); Wendisch, M. [Leipzig Univ. (Germany). LIM

    2012-02-01T23:59:59.000Z

    A meeting of 31 international experts on in situ measurements from aircraft was held to identify unresolved questions concerning ice formation and evolution in ice clouds, assess the current state of instrumentation that can address these problems, introduce emerging technology that may overcome current measurement issues and recommend future courses of action that can improve our understanding of ice cloud microphysical processes and their impact on the environment. The meeting proceedings and outcome has been described in detail in a manuscript submitted to the Bulletin of the American Meteorological Society (BAMS) on March 24, 2011. This paper is currently under review. The remainder of this summary, in the following pages, is the text of the BAMS article. A technical note that will be published by the National Center for Atmospheric Research is currently underway and is expected to be published before the end of the year.

  6. Nanotextured Anti-Icing Surfaces | GE Global Research

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

    researchers are developing super water-repellent coatings to improve moisture control in steam turbines to enable higher efficiency. They also are exploring these coatings for...

  7. Nanotextured Anti-Icing Surfaces | GE Global Research

    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 CodesTransparency VisitSilver Toyota PriusNSRdiodesScience

  8. 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.

  9. Improving parameter estimation and water table depth simulation in a land surface model using GRACE water storage and estimated base flow data

    E-Print Network [OSTI]

    Lo, Min-Hui; Famiglietti, James S; Yeh, P. J.-F.; Syed, T. H

    2010-01-01T23:59:59.000Z

    2007), Estimating ground water storage changes in thestorage (i.e. , all of the snow, ice, surface water, soil moisture, and ground-

  10. 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

  11. 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

  12. 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

  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. A transitioning Arctic surface energy budget: the impacts of solar zenith angle, surface albedo and cloud radiative forcing

    E-Print Network [OSTI]

    Shupe, Matthew

    A transitioning Arctic surface energy budget: the impacts of solar zenith angle, surface albedo Springer-Verlag 2010 Abstract Snow surface and sea-ice energy budgets were measured near 87.5°N during indicated four distinct tempera- ture regimes, characterized by varying cloud, thermody- namic and solar

  15. A transitioning Arctic surface energy budget: the impacts of solar zenith angle, surface albedo and cloud radiative forcing

    E-Print Network [OSTI]

    Brooks, Ian M.

    A transitioning Arctic surface energy budget: the impacts of solar zenith angle, surface albedo surface and sea-ice energy budgets were measured near 87.5°N during the Arctic Summer Cloud Ocean Study regimes, characterized by varying cloud, thermody- namic and solar properties. An initial warm, melt

  16. 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.

  17. 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.

  18. 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...

  19. 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.

  20. 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.

  1. 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 ...

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. Liquid Water Oceans in Ice Giants

    E-Print Network [OSTI]

    Sloane J. Wiktorowicz; Andrew P. Ingersoll

    2006-09-26T23:59:59.000Z

    Aptly named, ice giants such as Uranus and Neptune contain significant amounts of water. While this water cannot be present near the cloud tops, it must be abundant in the deep interior. We investigate the likelihood of a liquid water ocean existing in the hydrogen-rich region between the cloud tops and deep interior. Starting from an assumed temperature at a given upper tropospheric pressure (the photosphere), we follow a moist adiabat downward. The mixing ratio of water to hydrogen in the gas phase is small in the photosphere and increases with depth. The mixing ratio in the condensed phase is near unity in the photosphere and decreases with depth; this gives two possible outcomes. If at some pressure level the mixing ratio of water in the gas phase is equal to that in the deep interior, then that level is the cloud base. Alternately, if the mixing ratio of water in the condensed phase reaches that in the deep interior, then the surface of a liquid ocean will occur. We find that Neptune is both too warm (photospheric temperature too high) and too dry (mixing ratio of water in the deep interior too low) for liquid oceans to exist at present. To have a liquid ocean, Neptune's deep interior water to gas ratio would have to be higher than current models allow, and the density at 19 kbar would have to be ~ 0.8 g/cm^3. Such a high density is inconsistent with gravitational data obtained during the Voyager flyby. As Neptune cools, the probability of a liquid ocean increases. Extrasolar "hot Neptunes," which presumably migrate inward toward their parent stars, cannot harbor liquid water oceans unless they have lost almost all of the hydrogen and helium from their deep interiors.

  7. The Formation of Ice Giants in a Packed Oligarchy: Instability and Aftermath

    E-Print Network [OSTI]

    Eric B. Ford; Eugene Chiang

    2007-01-28T23:59:59.000Z

    As many as 5 ice giants--Neptune-mass planets composed of 90% ice and rock and 10% hydrogen--are thought to form at heliocentric distances of 10-25 AU on closely packed orbits spaced ~5 Hill radii apart. Such oligarchies are ultimately unstable. Once the parent disk of planetesimals is sufficiently depleted, oligarchs perturb one another onto crossing orbits. We explore both the onset and the outcome of the instability through numerical integrations, including dynamical friction cooling of planets by a planetesimal disk whose properties are held fixed. To trigger instability and the ejection of the first ice giant in systems having an original surface density in oligarchs of Sigma ~ 1 g/cm^2, the disk surface density s must fall below 0.1 g/cm^2. Ejections are predominantly by Jupiter and occur within 10 Myr. To eject more than 1 oligarch requires s ice giants lie inside 30 AU and have their orbits circularized by dynamical friction. Our numerical simulations support the idea that planetary systems begin in more crowded and compact configurations, like those of shear-dominated oligarchies. In contrast to previous studies, we identify s < 0.1 Sigma as the regime relevant for understanding the evolution of the outer solar system, and we encourage future studies to concentrate on this regime while relaxing our assumption of a fixed planetesimal disk.

  8. Critical Mechanisms for the Formation of Extreme Arctic Sea-Ice Extent in the Summers of 2007 and 1996

    SciTech Connect (OSTI)

    Dong, Xiquan; Zib, Benjamin J.; Xi, Baike; Stanfield, Ryan; Deng, Yi; Zhang, Xiangdong; Lin, B.; Long, Charles N.

    2014-07-29T23:59:59.000Z

    A warming Arctic climate is undergoing significant e 21 nvironmental change, most evidenced by the reduction of Arctic sea-ice extent during the summer. In this study, we examine two extreme anomalies of September sea-ice extent in 2007 and 1996, and investigate the impacts of cloud fraction (CF), atmospheric precipitable water vapor (PWV), downwelling longwave flux (DLF), surface air temperature (SAT), pressure and winds on the sea-ice variation in 2007 and 1996 using both satellite-derived sea-ice products and MERRA reanalysis. The area of the Laptev, East Siberian and West Chukchi seas (70-90oN, 90-180oE) has experienced the largest variation in sea-ice extent from year-to-year and defined here as the Area Of Focus (AOF). The record low September sea-ice extent in 2007 was associated with positive anomalies 30 of CF, PWV, DLF, and SAT over the AOF. Persistent anti-cyclone positioned over the Beaufort Sea coupled with low pressure over Eurasia induced easterly zonal and southerly meridional winds. In contrast, negative CF, PWV, DLF and SAT anomalies, as well as opposite wind patterns to those in 2007, characterized the 1996 high September sea-ice extent. Through this study, we hypothesize the following positive feedbacks of clouds, water vapor, radiation and atmospheric variables on the sea-ice retreat during the summer 2007. The record low sea-ice extent during the summer 2007 is initially triggered by the atmospheric circulation anomaly. The southerly winds across the Chukchi and East Siberian seas transport warm, moist air from the north Pacific, which is not only enhancing sea-ice melt across the AOF, but also increasing clouds. The positive cloud feedback results in higher SAT and more sea-ice melt. Therefore, 40 more water vapor could be evaporated from open seas and higher SAT to form more clouds, which will enhance positive cloud feedback. This enhanced positive cloud feedback will then further increase SAT and accelerate the sea-ice retreat during the summer 2007.

  9. 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...

  10. 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

  11. 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

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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)

  17. 255FEBRUARY 2002AMERICAN METEOROLOGICAL SOCIETY | he Surface Heat Budget of the Arctic Ocean

    E-Print Network [OSTI]

    Shupe, Matthew

    that determine the surface energy budget and the sea­ice mass balance in the Arctic (Moritz et al. 1993; Perovich of the vertical and horizontal energy exchanges within the ocean­ice­atmosphere system. The SHEBA pro- gram for Atmospheric Research, Boulder, Colorado; TURENNE--Canadian Coast Guard, Quebec City, Quebec, Canada; SERREZE

  18. Sediment-rich meltwater plumes and ice-proximal fans at the margins of modern and ancient tidewater glaciers: Observations and modelling

    E-Print Network [OSTI]

    Dowdeswell, Julian A.; Hogan, Kelly A.; Arnold, Neil S.; Mugford, Ruth I.; Wells, Martin; Hirst, J. Philip P.; Decalf, Carole

    2015-04-11T23:59:59.000Z

    products), together with calculated solar radiation receipts, to calculate melt. The ‘degree-day’ parameters relating temperature and solar radiation receipts to melting differ between ice and snow surfaces, to account for the lower albedo of ice... Basin, the sand prone component of the larger of these subaqueous outwash events can be tracked for 10 to 15 km in radius; in the proximal areas, a single event may have deposited 2 to 3 m of sandstone (Hirst, 2012) although, typically, the fans were...

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

    E-Print Network [OSTI]

    Nørvåg, 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

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

    E-Print Network [OSTI]

    Nørvåg, 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

  1. 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

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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

  14. 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 ...

  15. Real-time Non-contact Millimeter Wave Characterization of Water-Freezing and Ice-Melting Dynamics

    SciTech Connect (OSTI)

    Sundaram, S. K.; Woskov, Paul P.

    2008-11-12T23:59:59.000Z

    We applied millimeter wave radiometry for the first time to monitor water-freezing and ice-melting dynamics in real-time non-contact. The measurements were completed at a frequency of 137 GHz. Small amounts (about 2 mL) of freshwater or saltwater were frozen over a Peltier cooler and the freezing and melting sequence was recorded. Saltwater was prepared in the laboratory that contained 3.5% of table salt to simulate the ocean water. The dynamics of freezing-melting was observed by measuring the millimeter wave temperature as well as the changes in the ice or water surface reflectivity and position. This was repeated using large amounts of freshwater and saltwater (800 mL) mimicking glaciers. Millimeter wave surface level fluctuations indicated as the top surface melted, the light ice below floated up indicating lower surface temperature until the ice completely melted. Our results are useful for remote sensing and tracking temperature for potentially large-scale environmental applications, e.g., global warming.

  16. Ice and Climate News, No. 6, August 2005 8. Okishev, P.A., and V.S. Reviakin.1966. Alakhinsky

    E-Print Network [OSTI]

    Priscu, John C.

    radiation transmits through the ice and heats the dark sediment and organic matter at depth. Once formed, 1985]. Water may be contained within cryoconite holes for several months each year, and the holes of solar heating of sediment and dark-coloured algae resident on the glacier surface. The hole depth

  17. Interannual Variations of Arctic Cloud Types in Relation to Sea Ice RYAN EASTMAN AND STEPHEN G. WARREN

    E-Print Network [OSTI]

    Hochberg, Michael

    longwave cloud radiative effect (CRE), sug- gesting that infrared radiation emitted toward the surface and cloud temperatures greater than 2318C. Cloud radiative effect over the Arctic likely varies seasonally of clouds have different effects on sea ice. Visual cloud reports from land and ocean regions of the Arctic

  18. Prospecting for lunar ice using a multi-rover cooperative team

    SciTech Connect (OSTI)

    KLARER,PAUL R.; FEDDEMA,JOHN T.; LEWIS,CHRISTOPHER L.

    2000-02-11T23:59:59.000Z

    A multi-rover cooperative team or swarm developed by Sandia National Laboratories is described, including various control methodologies that have been implemented to date. How the swarm's capabilities could be applied to a lunar ice prospecting mission is briefly explored. Some of the specific major engineering issues that must be addressed to successfully implement the swarm approach to a lunar surface mission are outlined, and potential solutions are proposed.

  19. 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

  20. 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.

  1. Annual satellite imaging of the world's glaciers Assessment of glacier extent and change

    E-Print Network [OSTI]

    GLIMS HIGH ICE Annual satellite imaging of the world's glaciers Assessment of glacier extent and change Development and population of a digital glacier data inventory #12;Skeletal remains of what was a debris-covered glacier near Mt. Everest J.S. Kargel, April 2001 #12;#12;#12;Global Land Ice Measurements

  2. 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.

  3. Pancake bouncing on superhydrophobic surfaces

    E-Print Network [OSTI]

    Liu, Yahua; Xu, Xinpeng; Qian, Tiezheng; Yeomans, Julia M; Wang, Zuankai

    2014-01-01T23:59:59.000Z

    Engineering surfaces that promote rapid drop detachment is of importance to a wide range of applications including anti-icing, dropwise condensation6, and self-cleaning. Here we show how superhydrophobic surfaces patterned with lattices of submillimetre-scale posts decorated with nano-textures can generate a counter-intuitive bouncing regime: drops spread on impact and then leave the surface in a flattened, pancake shape without retracting. This allows for a four-fold reduction in contact time compared to conventional complete rebound. We demonstrate that the pancake bouncing results from the rectification of capillary energy stored in the penetrated liquid into upward motion adequate to lift the drop. Moreover, the timescales for lateral drop spreading over the surface and for vertical motion must be comparable. In particular, by designing surfaces with tapered micro/nanotextures which behave as harmonic springs, the timescales become independent of the impact velocity, allowing the occurrence of pancake bou...

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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...

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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...

  5. 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...

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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...

  12. 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

  13. Neutrino Data from IceCube and its Predecessor at the South Pole, the Antarctic Muon and Neutrino Detector Array (AMANDA)

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

    Abbasi, R.

    IceCube is a neutrino observatory for astrophysics with parts buried below the surface of the ice at the South Pole and an air-shower detector array exposed above. The international group of sponsors, led by the National Science Foundation (NSF), that designed and implemented the experiment intends for IceCube to operate and provide data for 20 years. IceCube records the interactions produced by astrophysical neutrinos with energies above 100 GeV, observing the Cherenkov radiation from charged particles produced in neutrino interactions. Its goal is to discover the sources of high-energy cosmic rays. These sources may be active galactic nuclei (AGNs) or massive, collapsed stars where black holes have formed.[Taken from http://www.icecube.wisc.edu/] The data from IceCube's predecessor experiment and detector, AMANDA, IceCube’s predecessor detector and experiment is also available at this website. AMANDA pioneered neutrino detection in ice. Over a period of years in the 1990s, detecting “strings” were buried and activated and by 2000, AMANDA was successfully recording an average of 1,000 neutrino events per year. This site also makes available many images and video from the two experiments.

  14. 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.

  15. 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

  16. THEORETICAL SPECTRA OF TERRESTRIAL EXOPLANET SURFACES

    SciTech Connect (OSTI)

    Hu Renyu; Seager, Sara [Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Ehlmann, Bethany L., E-mail: hury@mit.edu [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States)

    2012-06-10T23:59:59.000Z

    We investigate spectra of airless rocky exoplanets with a theoretical framework that self-consistently treats reflection and thermal emission. We find that a silicate surface on an exoplanet is spectroscopically detectable via prominent Si-O features in the thermal emission bands of 7-13 {mu}m and 15-25 {mu}m. The variation of brightness temperature due to the silicate features can be up to 20 K for an airless Earth analog, and the silicate features are wide enough to be distinguished from atmospheric features with relatively high resolution spectra. The surface characterization thus provides a method to unambiguously identify a rocky exoplanet. Furthermore, identification of specific rocky surface types is possible with the planet's reflectance spectrum in near-infrared broad bands. A key parameter to observe is the difference between K-band and J-band geometric albedos (A{sub g}(K) - A{sub g}(J)): A{sub g}(K) - A{sub g}(J) > 0.2 indicates that more than half of the planet's surface has abundant mafic minerals, such as olivine and pyroxene, in other words primary crust from a magma ocean or high-temperature lavas; A{sub g}(K) - A{sub g}(J) < -0.09 indicates that more than half of the planet's surface is covered or partially covered by water ice or hydrated silicates, implying extant or past water on its surface. Also, surface water ice can be specifically distinguished by an H-band geometric albedo lower than the J-band geometric albedo. The surface features can be distinguished from possible atmospheric features with molecule identification of atmospheric species by transmission spectroscopy. We therefore propose that mid-infrared spectroscopy of exoplanets may detect rocky surfaces, and near-infrared spectrophotometry may identify ultramafic surfaces, hydrated surfaces, and water ice.

  17. From near-surface to root-zone soil moisture using an exponential filter: an assessment of the method based on

    E-Print Network [OSTI]

    Boyer, Edmond

    provides a means to quantitatively describe the water content of a shallow near-surface soil layer, wg of the method based on in-situ observations and model simulations C. Albergel1 , C. Rüdiger1,* , T. Pellarin2. A recursive exponential filter equation using a time constant, T, is used to compute a soil water index

  18. Global Climate Modeling of the Martian water cycle with improved microphysics and radiatively active water ice clouds

    E-Print Network [OSTI]

    Navarro, Thomas; Forget, François; Spiga, Aymeric; Millour, Ehouarn; Montmessin, Franck

    2013-01-01T23:59:59.000Z

    Radiative effects of water ice clouds have noteworthy consequences on the Martian atmosphere, its thermal structure and circulation. Accordingly, the inclusion of such effects in the LMD Mars Global Climate Model (GCM) greatly modifies the simulated Martian water cycle. The intent of this paper is to address the impact of radiatively active clouds on atmospheric water vapor and ice in the GCM and improve its representation. We propose a new enhanced modeling of the water cycle, consisting of detailed cloud microphysics with dynamic condensation nuclei and a better implementation of perennial surface water ice. This physical modeling is based on tunable parameters. This new version of the GCM is compared to the Thermal Emission Spectrometer observations of the water cycle. Satisfying results are reached for both vapor and cloud opacities. However, simulations yield a lack of water vapor in the tropics after Ls=180{\\deg} which is persistent in simulations compared to observations, as a consequence of aphelion c...

  19. Distributed road assessment system

    DOE Patents [OSTI]

    Beer, N. Reginald; Paglieroni, David W

    2014-03-25T23:59:59.000Z

    A system that detects damage on or below the surface of a paved structure or pavement is provided. A distributed road assessment system includes road assessment pods and a road assessment server. Each road assessment pod includes a ground-penetrating radar antenna array and a detection system that detects road damage from the return signals as the vehicle on which the pod is mounted travels down a road. Each road assessment pod transmits to the road assessment server occurrence information describing each occurrence of road damage that is newly detected on a current scan of a road. The road assessment server maintains a road damage database of occurrence information describing the previously detected occurrences of road damage. After the road assessment server receives occurrence information for newly detected occurrences of road damage for a portion of a road, the road assessment server determines which newly detected occurrences correspond to which previously detected occurrences of road damage.

  20. 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.

  1. Solar Energetic Particle Spectrum on 13 December 2006 Determined by IceTop

    SciTech Connect (OSTI)

    IceCube Collaboration; Klein, Spencer

    2008-10-11T23:59:59.000Z

    The IceTop air shower array now under construction at the South Pole as the surface component of the IceCube neutrino telescope (Achterberg et al. 2006) detected an unusual near-solar-minimum Ground Level Enhancement (GLE) after a solar flare on 13 December 2006. Beginning at 0220 UT, the 4B class flare occurred at solar coordinates S06 W24, accompanied by strong (X3.4) X-ray emission and type II and IV radio bursts. The LASCO coronagraph on the SOHO spacecraft observed a halo CME launch from the Sun at {approx} 0225 UT with speed estimated to be {approx} 1770 km/s. We have begun (Bieber et al. 2007) a comprehensive analysis of the propagation of solar energetic particles in this event. However the focus of this Letter is the new and unique ability of IceTop to derive the energy spectrum of these particles in the multi-GeV regime from a single detector with a well defined viewing direction. When completed, IceTop will have approximately 500 square meters of ice Cherenkov collecting area arranged in an array of 80 stations on a 125 m triangular grid to detect air showers from one PeV to one EeV. Each station consists of two, two meter diameter tanks filled with ice to a depth of 90 cm. Tanks are instrumented with two Digital Optical Modules (DOM) operated at different gain settings to provide appropriate dynamic range to cover both large and small air showers. Each DOM contains a 10 inch photomultiplier and an advanced readout system capable of digitizing the full waveform. For historical reasons, the two discriminator counting rates recorded in each DOM are termed SPE (Single Photo Electron), and MPE (Multi Photo Electron). In the present analysis the SPE threshold corresponds approximately to 20 photoelectrons (PE), and the MPE threshold to 100 PE. Due to the high altitude (2835m) and the nearly zero geomagnetic cutoff at the South Pole, secondary particle spectra at the detector retain a significant amount of information on the spectra of the primary particles. In a thin, ionization detector these secondary particles either would not interact, or would produce virtually indistinguishable signals. This is not the case in the thick Ice-Top detector, where a traversing muon produces 130 PE and the typical electron only 15 PE. Signal amplitude therefore carries information about the composition and spectra of the incident particles, albeit integrated over broad regions of the spectrum. In particular, differences in counting rates of discriminators at different thresholds allow us to infer the particle spectrum incident at the top of the atmosphere.

  2. The Surface of 2003EL61 in the Near Infrared

    E-Print Network [OSTI]

    C. A. Trujillo; M. E. Brown; K. M. Barkume; E. L. Schaller; D. L. Rabinowitz

    2006-10-30T23:59:59.000Z

    We report the detection of crystalline water ice on the surface of 2003 EL61. Reflectance spectra were collected from Gemini North telescope from 1.0 to 2.4 micron wavelength range, and from the Keck telescope across the 1.4 to 2.4 micron wavelength range. The signature of crystalline water ice is obvious in all data collected. Like the surfaces of many outer solar system bodies, the surface of 2003 EL61 is rich in crystalline water ice, which is energetically less favored than amorphous water ice at low temperatures, suggesting that resurfacing processes may be taking place. The near infrared color of the object is much bluer than a pure water ice model. Adding a near infrared blue component such as hydrogen cyanide or phyllosilicate clays improves the fit considerably, with hydrogen cyanide providing the greatest improvement. The addition of hydrated tholins and bitumens also improves the fit but is inconsistent with the neutral V-J reflectance of 2003 EL61. A small decrease in reflectance beyond 2.3 micron may be attributable to cyanide salts. Overall, the reflected light from 2003 EL61 is best fit by a model of 2/3 to 4/5 pure crystalline water ice and 1/3 to 1/5 near infrared blue component such as hydrogen cyanide or kaolinite. The surface of 2003 EL61 is unlikely to be covered by significant amounts of dark material such as carbon black, as our pure ice models reproduce published albedo estimates derived from the spin state of 2003 EL61.

  3. Surface Energy and Surface Proton Order of Ice Ih Ding Pan,1,2

    E-Print Network [OSTI]

    Alavi, Ali

    -Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany 3 London Centre for Nanotechnology, University College London, London WC1H 0AJ, United Kingdom 4 Materials Simulation Laboratory, University College London, London WC1H 0AJ, United Kingdom 5 Department of Chemistry, University College London, London WC1H 0AJ, United

  4. 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 $\

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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...

  19. 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

  20. 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....

  1. 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.

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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.

  10. 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

  11. 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

  12. 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...

  13. 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

  14. 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

  15. 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

  16. Isotope effect in the photochemical decomposition of CO{sub 2} (ice) by Lyman-{alpha} radiation

    SciTech Connect (OSTI)

    Yuan Chunqing; Yates, John T. Jr. [Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904 (United States)

    2013-04-21T23:59:59.000Z

    The photochemical decomposition of CO{sub 2}(ice) at 75 K by Lyman-{alpha} radiation (10.2 eV) has been studied using transmission infrared spectroscopy. An isotope effect in the decomposition of the CO{sub 2} molecule in the ice has been discovered, favoring {sup 12}CO{sub 2} photodecomposition over {sup 13}CO{sub 2} by about 10%. The effect is caused by electronic energy transfer from the excited CO{sub 2} molecule to the ice matrix, which favors quenching of the heavier electronically-excited {sup 13}CO{sub 2} molecule over {sup 12}CO{sub 2}. The effect is similar to the Menzel-Gomer-Redhead isotope effect in desorption from adsorbed molecules on surfaces when electronically excited. An enhancement of the rate of formation of lattice-trapped CO and CO{sub 3} species is observed for the photolysis of the {sup 12}CO{sub 2} molecule compared to the {sup 13}CO{sub 2} molecule in the ice. Only 0.5% of the primary photoexcitation results in O-CO bond dissociation to produce trapped-CO and trapped-CO{sub 3} product molecules and the majority of the electronically-excited CO{sub 2} molecules return to the ground state. Here either vibrational relaxation occurs (majority process) or desorption of CO{sub 2} occurs (minority process) from highly vibrationally-excited CO{sub 2} molecules in the ice. The observation of the {sup 12}C/{sup 13}C isotope effect in the Lyman-{alpha} induced photodecomposition of CO{sub 2} (ice) suggests that over astronomical time scales the isotope enrichment effect may distort historical information derived from isotope ratios in space wherever photochemistry can occur.

  17. 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

  18. 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

  19. Retrieval of Cloud Ice Water Content Profiles from Advanced Microwave Sounding Unit-B Brightness Temperatures Near the Atmospheric Radiation Measurement Southern Great Plains Site

    SciTech Connect (OSTI)

    Seo, E-K.; Liu, G.

    2005-03-18T23:59:59.000Z

    One of the Atmospheric Radiation Measurement (ARM) Program important goals is to develop and test radiation and cloud parameterizations of climate models using single column modeling (SCMs) (Randall et al. 1996). As forcing terms, SCMs need advection tendency of cloud condensates besides the tendencies of temperature, moisture and momentum. To compute the tendency terms of cloud condensates, 3D distribution of cloud condensates over a scale much larger than the climate model's grid scale is needed. Since they can cover a large area within a short time period, satellite measurements are useful utilities to provide advection tendency of cloud condensates for SCMs. However, so far, most satellite retrieval algorithms only retrieve vertically integrated quantities, for example, in the case of cloud ice, ice water path (IWP). To fulfill the requirement of 3D ice water content field for computing ice water advection, in this study, we develop an ice water content profile retrieval algorithm by combining the vertical distribution characteristics obtained from long-term surface radar observations and satellite high-frequency microwave observations that cover a large area. The algorithm is based on the Bayesian theorem using a priori database derived from analyzing cloud radar observations at the Southern Great Plains (SGP) site. The end product of the algorithm is a 3D ice water content covering 10{sup o} x 10{sup o} surrounding the SGP site during the passage of the satellite. This 3D ice water content, together with wind field analysis, can be used to compute the advection tendency of ice water for SCMs.

  20. SIZE AND TEMPERATURE DEPENDENCE IN THE FAR-IR SPECTRA OF WATER ICE PARTICLES

    SciTech Connect (OSTI)

    Medcraft, Chris; McNaughton, Don; Thompson, Chris D. [School of Chemistry, Monash University, Wellington Road, Clayton, Victoria 3800 (Australia); Appadoo, Dominique [Australian Synchrotron, Blackburn Road, Clayton, Victoria 3168 (Australia); Bauerecker, Sigurd [Institut fuer Physikalische und Theoretische Chemie, Technische Universitaet Braunschweig, Hans-Sommer-Strasse 10, D-38106 Braunschweig (Germany); Robertson, Evan G., E-mail: E.Robertson@latrobe.edu.au [Department of Chemistry and La Trobe Institute of Molecular Sciences, La Trobe University, Bundoora, Victoria 3086 (Australia)

    2012-10-10T23:59:59.000Z

    Spectra of water-ice aerosol particles have been measured in the far-IR region using synchrotron radiation. The particles in the nanoscale size regime of 1-100 nm were formed by rapid collisional cooling at temperatures ranging from 4 to 190 K. The spectra show the characteristic bands centered near 44 {mu}m (230 cm{sup -1}) and 62 {mu}m (160 cm{sup -1}) associated with the intermolecular lattice modes of crystalline ice at all temperatures, in contrast to previous studies of thin films formed by vapor deposition where amorphous ice is generated below 140 K. The bands shift to higher wavenumber values as the temperature is reduced, consistent with the trend seen in earlier studies, but in our experiments the actual peak positions in the aerosol particle spectra are consistently higher by ca. 4 cm{sup -1}. This finding has implications for the potential use of these spectral features as a temperature probe. The particle sizes are small enough for their spectra to be free of scattering effects, and therefore provide a means to assess imaginary refractive index values obtained through Kramers-Kronig analyses of thin film spectra.

  1. 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.

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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.

  7. Toward a Deterministic Model of Planetary Formation V. Accumulation Near the Ice Line

    E-Print Network [OSTI]

    Shigeru Ida; D. N. C. Lin

    2008-06-01T23:59:59.000Z

    We address two outstanding issues in the sequential accretion scenario for gas giant planet formation, the retention of dust grains in the presence of gas drag and that of cores despite type I migration. The efficiency of these processes is determined by the disk structure. Theoretical models suggest that planets form in protostellar disk regions with an inactive neutral ``dead zone'' near the mid plane, sandwiched together by partially ionized surface layers where magnetorotational instability is active. Due to a transition in the abundance of dust grains, the active layer's thickness decreases abruptly near the ice line. Over a range of modest accretion rates ($\\sim 10^{-9}-10^{-8} M_\\odot$ yr$^{-1}$), the change in the angular momentum transfer rate leads to local surface density and pressure distribution maxima near the ice line. The azimuthal velocity becomes super-Keplerian and the grains accumulate in this transition zone. This barrier locally retains protoplanetary cores and enhances the heavy element surface density to the critical value needed to initiate efficient gas accretion. It leads to a preferred location and epoch of gas giant formation. We simulate and reproduce the observed frequency and mass-period distribution of gas giants around solar type stars without having to greatly reduce the type I migration strength. The mass function of the short-period planets can be utilized to calibrate the efficiency of type I migration and to extrapolate the fraction of stars with habitable terrestrial planets.

  8. 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.

  9. 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...

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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...

  18. 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

  19. 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...

  20. Surface Soil

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

    Surface Soil Surface Soil We compare local soil samples with samples collected from northern New Mexico locations that are beyond the range of potential influence from normal...

  1. Supraglacial lakes on the Larsen B Ice Shelf, Antarctica, and Paakitsoq Region, Greenland: a comparative study

    E-Print Network [OSTI]

    Banwell, Alison F.; Caballero, Martamaria; Arnold, Neil S.; Glasser, Neil F.; Cathles, L. Mac; MacAyeal, Douglas R.

    2014-05-01T23:59:59.000Z

    .epsl.2011.04.014. 427 Box, J. E., and K. Ski (2007), Remote sounding of Greenland supraglacial melt lakes: 428 implications for subglacial hydraulics, J. Glaciol., 53(181), 257–265, 429 doi:10.3189/172756507782202883. 430 Bromwich, D. H., J. P. Nicolas... , Geophys. Res. Lett., 39(16), L16504, 510 doi:10.1029/2012GL052413. 511 Mobley, C. D. (1994), Light and water: radiative transfer in natural waters. 512 Academic Press, San Diego, 592. 513 Phillips, H. A. (1998), Surface meltstreams on the Amery Ice...

  2. Microsoft PowerPoint - TWP-ICE_2006Nov_Rad.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 82981-1cnHighandSWPA / SPRA / USACE SWPA / SPRA / USACETWP-ICE: Surface Radiation

  3. 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.

  4. 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.

  5. EROSION AND DEPOSITION ON PLANETARY SURFACES BY WIND,

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    , Ecuador #12;How long did this take to form?? #12;Titan · Surface is mostly composed of water ice and disruption. #12;Types of Meteorites: Primitive (80% of total) · Primitive meteorites (chondrites): · Solar System's oldest material (~4.57 billion yr) · Accreted cold from the solar nebula. ­ Ordinary: containing

  6. The Effect of Host Star Spectral Energy Distribution and Ice-Albedo Feedback on the Climate of Extrasolar Planets

    E-Print Network [OSTI]

    Shields, Aomawa L; Bitz, Cecilia M; Pierrehumbert, Raymond T; Joshi, Manoj M; Robinson, Tyler D

    2013-01-01T23:59:59.000Z

    Planetary climate can be affected by the interaction of the host star spectral energy distribution with the wavelength-dependent reflectivity of ice and snow. Here we explore this effect using a one dimensional (1-D), line-by-line, radiative-transfer model to calculate broadband planetary albedos as input to a seasonally varying, 1-D energy-balance climate model. A three-dimensional general circulation model is also used to explore the atmosphere's response to changes in incoming stellar radiation, or instellation, and surface albedo. Using this hierarchy of models we simulate planets covered by ocean, land, and water ice of varying grain size, with incident radiation from stars of different spectral types. Terrestrial planets orbiting stars with higher near-UV radiation exhibit a stronger ice-albedo feedback. We find that ice-covered conditions occur on an F-dwarf planet with only a 2% reduction in instellation relative to the present instellation on Earth, assuming fixed CO2 (present atmospheric level on Ea...

  7. 2009 Community Sequencing Program: Life Under Ice

    SciTech Connect (OSTI)

    Victo Kunin, PhD (Project co-PI) [Project co-PI; Microbial Ecology Group, DOE JGI; Phil Hugenholtz, PhD (CSP Project PI) [CSP Project PI; Microbial Ecology Program Head, DOE JGI

    2008-09-25T23:59:59.000Z

    A JGI Multimedia Presentation: Buried deep beneath the surface of Antarctica is a fresh water lake, Lake Vostok.

  8. 2009 Community Sequencing Program: Life Under Ice

    ScienceCinema (OSTI)

    Victo Kunin, PhD (Project co-PI); Microbial Ecology Group, DOE JGI; Phil Hugenholtz, PhD (CSP Project PI); Microbial Ecology Program Head, DOE JGI

    2010-09-01T23:59:59.000Z

    A JGI Multimedia Presentation: Buried deep beneath the surface of Antarctica is a fresh water lake, Lake Vostok.

  9. 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.

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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.

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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.