Mrs
Livia Eleonora Bove
(CNRS & Université P&M Curie, EPFL)
08/01/2018, 10:05
keynote
Compressed water is overspread on Earth at depth and in the extra-terrestrial space, both interstellar and on outer planets and moons (ice bodies) [1]. Under the conditions experienced in these celestial bodies water displays an incredibly rich phase diagram, including seventeen known crystalline phases and three amorphous states, and predicted exotic properties like plasticity [2], ionization...
Prof.
Niall English
(University College Dublin, Chemical Engineering)
08/01/2018, 10:50
Phases of Ice
Talk
We report ab-initio molecular dynamics, using state-of-the-art non-local dispersion, to study, inter alia, the structural, hydrogen-bonding, vibrational and Raman properties of ices Ih, VII and XVII at appropriate temperature and pressure ranges for their stability. In many senses, probing of ice Ih serves as a validation tool for the functional, with reasonable agreement with experiment.
...
Dr
Andrzej Falenty
(GZG Abt. Kristallographie Uni Göttingen)
08/01/2018, 11:10
Amorphous Ice
Talk
Formation of gas hydrates from ice is generally a slow process due to the intrinsically sluggish solid-state mass transfer (Salamatin et al. 2015). Small size Ne, H2 and He are an exception to this rule by being able to penetrate into the lattice of the ordinary ice Ih with ease. Upon further compression ice Ih presaturated with He-gas was found to transform rapidly into gas-filled ice II....
Dr
Arnaud DESMEDT
(CNRS)
08/01/2018, 11:30
Phases of Ice
Talk
In addition to their various applications in the environment, energy and technology fields, gas hydrates are supposed to be involved in the formation of planetesimals, comets and other planets, such as Titan or Enceladus, both being Saturn’s moons. For instance, CO gas hydrate was one of the hydrates especially highlighted in the first work outlining this hypothetical hydrate formation in...
Prof.
Changqing Sun
(NTU, SIngapore)
08/01/2018, 13:20
Phases of Ice
Talk
As the source and central part of all lives, water is most abundant yet least known. This presentation shares the recent progress [1-6]: (i) correlation of the length scale, structure order, and mass density of molecular packing in water ice; (ii) potential paths for O:H-O bond at relaxation; and anomalies of water ice under (iii) compression; (iv) molecular under-coordination; and (v) thermal...
Mr
Tobias M. Gasser
(University of Innsbruck)
08/01/2018, 13:40
Phases of Ice
Talk
In the last decade five new ice phases were experimentally prepared. Two of them(1, 2) are empty clathrate hydrates and three of them(3, 4) represent hydrogen ordered counterparts of previously known disordered ice phases. In our experiments, we investigated hydrogen ordering in ice VI samples upon cooling at pressures up to 1.8 GPa. Using calorimetry, dielectric relaxation spectroscopy, Raman...
Prof.
Yoshinori Furukawa
(Institute of Low Temperature Science, Hokkaido University)
08/01/2018, 14:05
keynote
Antifreeze protein (AFP) and antifreeze glycoprotein (AFGP) molecules adsorb on ice-water interfaces and control the ice crystal growth. However, there still remain many missing pieces of the puzzle for the growth control mechanism. The basic observations from the viewpoint of crystal growth, for example, in-situ observations of morphologies, precise measurements of growth rates,...
Dr
gilles demange
(GPM, University of Rouen)
08/01/2018, 14:50
Ice Crystal Growth
Talk
Simulating ice crystal growth is a major issue for meteorology and aircraft safety [1]. Notwithstanding, very few models currently succeed in reproducing the diversity of snowflake forms in three dimensions, and the link between model parameters and thermodynamic quantities is far from being established. Here, we present a 3D modified phase field model that describes the subtlety of the...
Prof.
Etsuro Yokoyama
(Computer Centre, Gakushuin University)
08/01/2018, 15:10
Ice Crystal Growth
Talk
We measured the growth rates of secondary branches of a dendritic ice crystal growing from supercooled heavy water in both microgravity and 1g conditions. We have analyzed recorded sequences of images of microgravity experiments that were carried out 134 times in the International Space Station(ISS) and measured the growth rates of both the tip of a primary dendrite and the basal faces of an...
Quirine Krol
(WSL Institute for Snow and Avalanche Research SLF)
08/01/2018, 15:30
Ice Crystal Growth
Talk
While the growth of single ice-crystals in the atmosphere is reasonably well understood, the microstructure dynamics of snow on the ground as the collective growth of aggregated crystals, is still lacking a unified treatment based on first principles of ice crystal growth. One of the key-challenges is the lack of models for the microstructure evolution of the bicontinuous ice matrix. To this...
Dr
Masakazu Matsumoto
(Research Institute for Interdisciplinary Science, Okayama University)
08/01/2018, 16:30
Ice Crystal Growth
Talk
Among 17 known ice polymorphs, only two are less dense than normal ice, and they are made very recently by a tricky procedure, vacuum pumping the small guest molecules from clathrate hydrate. The discovery of low-density ice polymorphs opens the door to the survey on ices under negative pressures. Negative pressure is very hard to be accessed experimentally, and theoretical predictions are...
Mr
Fabian Mahrt
(Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, 8092, Switzerland)
08/01/2018, 16:50
Ice Crystal Growth
Talk
Soot particles are primary particles produced by incomplete combustion of both biomass and/or fossil fuels and thus constitute a major anthropogenic pollutant. They are generally complex internal mixtures of black carbon (BC) and organic matter (OM) (Bond et al., 2013; Petzold et al., 2013). While these properties strongly depend on the emission sources, they can be altered during atmospheric...
Dr
Ken Nagashima
(Institute of Low Temperature Science, Hokkaido University, Japan)
08/01/2018, 17:10
Ice Crystal Growth
Talk
Ice crystal surfaces are covered with quasi-liquid layers (QLLs) and it leads great influence on the global environment whether ice surfaces are dry or wet. For example, since QLLs enhance various chemical reactions in ice clouds, the formation of QLLs by atmospheric gases has been studied intensively. In particular, chemical reactions on ice surfaces in the presence of hydrogen chloride (HCl)...
Dr
Michel J. ROSSI
(Paul Scherrer Institute (PSI)), Dr
Riccardo Iannarelli
(EPFL)
08/01/2018, 17:30
Nucleation
Talk
A multidiagnostic Stirred Flow Reactor has been used to investigate heterogeneous nucleation of pure H2O ice from water vapor depositing on a silicon substrate mounted in a cryostat at controlled temperatures. The gas phase has been monitored using residual gas mass spectrometry, the cryogenic deposit was investigated using FTIR spectroscopy in transmission in the range 650 to 4000 cm-1 across...
Dr
Katrin Amann-Winkel
(Stockholm University)
09/01/2018, 08:30
keynote
The amorphous forms of water play an important role in the understanding of water´s anomalous properties. Computer simulations suggests that the anomalous behaviour of ambient and supercooled water could be explained by a two state model of water [1]. Since the discovery of two distinct amorphous states of ice with different density (high- and low density amorphous ice, HDA and LDA) it has...
Violeta Fuentes Landete
(Institute of Physical Chemistry, University of Innsbruck, Austria)
09/01/2018, 09:15
Amorphous Ice
Talk
Studies on doped crystalline ice phases have been done over the past decades. Dopants have allowed unlocking the kinetically hindered, but thermodynamically favored transitions to hydrogen ordered ices, allowing the discovery of ices XI[1], XIII[2], XIV[2] and XV[3]. The role of these dopants is to enhance the microscopic dynamics up to 100.000[4], as reveal by the dielectric studies. This...
Mr
Du Hyeong Lee
(Seoul National University)
09/01/2018, 09:35
Amorphous Ice
Talk
Amorphous solid water (ASW) has attracted much attention in the ice research community because of its unique properties as a metastable solid form of water and possible existence in interstellar clouds. ASW is kinetically metastable and undergoes a phase transition to crystalline ice (CI) upon heating; these phenomena have been studied in depth in recent years. [1-3] In this presentation, we...
Prof.
Werner F Kuhs
(University of Göttingen)
09/01/2018, 09:55
Phases of Ice
Talk
Crystallite size distributions (CSDs) provide important insights into the formation processes of materials, in particular the balance between nucleation and growth rates. Both equilibrium and non-equilibrium physical properties of the resulting polycrystalline gas hydrate assemblages will depend on the CSDs, in particular their mechanical properties as well as their interactions with any...
Prof.
Peter Kusalik
(University of Calgary)
09/01/2018, 10:50
keynote
Ice crystallization is ubiquitous in nature and has numerous important roles, technological applications and implications. Yet, the ordering processes associated with the nucleation and growth of ice crystals have proven difficult to study directly with experiments, in part due to their stochastic nature of the underlying molecular processes. Consequently, a complete molecular-level picture of...
Dr
Claudia Marcolli
(ETH Zurich, Institute for Atmospheric and Climate Science)
09/01/2018, 11:35
Nucleation
Talk
Mineral dust has lifetimes of several days in the atmosphere and can be transported over long distances. During transport, mineral dust particles may acquire a coating when they come in contact with reactive gases and semivolatile species or when they undergo cloud processing (e.g. Tang et al., 2016). Coatings can influence the ice nucleation (IN) efficiency of mineral dust in different ways....
Mr
Robert O. David
(Institute for Atmospheric and Climate Science, ETH Zürich)
09/01/2018, 11:55
Nucleation
Talk
Ice crystals in clouds play an important role in initiating precipitation and thus cloud lifetime which acts to moderate the Earth’s radiative balance. As such, understanding the mechanisms responsible for ice formation is necessary to quantify the impacts of anthropogenic climate change. Pore condensation and freezing (PCF), is a proposed mechanism for ice formation below water saturation. ...
Dr
Martin Luethi
(University of Zurich, Geography)
09/01/2018, 12:35
Poster
The iceberg calving process influences the geometry of a tidewater glacier,
and is in turn controlled by the terminus geometry through the stress field
which controls damage and fracture of the ice. A simple parametrization of
the stress field at the glacier terminus is obtained from the results of a
Finite Element model with varying water depths. Using this stress field in an
isotropic...
Dr
Bradley Paul Lipovsky
(Harvard University)
09/01/2018, 12:35
Poster
Distant storms, tsunamis, and earthquakes generate waves in floating ice shelves. In several instances, seismic observations have clearly demonstrated a mechanistic link between periods of elevated wave activity and iceberg calving. The detailed mechanical interpretation of observed seismograms is complicated, however, by the existence of numerous types of waves that propagate in the coupled...
Mr
Michael Chasnitsky
(The Hebrew University of Jerusalem)
09/01/2018, 12:35
PICO talk
When a moving solidification front encounters a foreign particle in the melt for example during freezing, it can either engulf it, or push and reject it. This interaction takes place in freezing of any colloidal suspension and is basic in metallurgy, freeze casting, frost heave, and cryopreservation. In this work we show that the interaction of the particles with the freezing front can be...
Dr
Martin Luethi
(University of Zurich, Geography)
09/01/2018, 12:35
Poster
Glacier ice at the melting temperature may contain up to 6% of unfrozen water,
as was inferred with indirect methods such as ice-penetrating radar. This
inter-grain water influences ice deformation, the thermal structure of ice
sheets, and subglacial hydrology.
We determined by the content of free water in-situ in ice caves and at the
base of serveral temperate glaciers. The...
Prof.
Yoshinori Furukawa
(Institute of Low Temperature Science, Hokkaido University)
09/01/2018, 12:35
PICO talk
The purpose of our research is to explore how type III AFP modifies the morphology and growth kinetics of ice crystals, and to reveal the action mechanisms of AFP-III.
In a glass capillary seed crystals of ice of hexagonal modification were formed in supercooled water with AFP-III concentrations of 0-0.8 mg/ml. Measurements of growth rates were performed by Mach-Zehnder interferometry at...
Prof.
Iwao Takei
(Hokuriku University)
09/01/2018, 12:35
Poster
In ice, the dielectric response signals of a Debye relaxation process have been measured parallel to the applied electric field. Here, we report response signals detected perpendicular to the applied field for ice samples. An alternating electric field (applied voltage V0: 5 Vp-p) of 1 Hz to 1 MHz was applied to a cube (1 × 1 × 1 cm) of single-crystal ice Ih between one pair of planes along...
Mr
Jan Eichler
(Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research)
09/01/2018, 12:35
Poster
Ice has a very high plastic anisotropy with easy dislocation glide on basal planes while glide on non-basal planes is much harder. Basal glide involves dislocations with Burgers vector b=, while glide on non-basal planes can involve dislocations with b=, b=[c] and b=<c+a>. During natural ductile flow of polar ice sheets most of the deformation is expected to occur by basal slip...
Mr
Hani Kang
(Seoul National University)
09/01/2018, 12:35
Poster
We examed the effect of applied electric field on collective phonon modes of a CO solid crystal. A strong electric field (~10⁸ V/m) was applied across a thin CO film grown on a metal substrate at 7 K by using the ice film capacitor method. Reflection absorption infrared spectroscopy (RAIRS) was used for monitoring the optical phonon modes of a CO film, where a longitudinal optical (LO) mode...
Dr
Jonathan Vermette
(Université de sherbrooke), Mr
Thomas Putaud
(Laboratoire d'Etudes du Rayonnement et de la Matière en Astrophysique et Atmosphères (LERMA), Sorbonne Universités, UPMC Univ. Paris 06, Observatoire de Paris, PSL Research University, CNRS UMR 8112, F-75005, Paris, France)
09/01/2018, 12:35
Poster
The properties of the nuclear spin isomers of the water molecule are of great interest in astrophysics since the ortho:para ratio (OPR) is assumed to provide insight into the formation mechanism and history of comets as well as other celestial bodies [1,2]. Technological advances are also foreseen for ortho-water enriched samples in magnetic resonance applications, in analogy with...
Prof.
Niall English
(UCD)
09/01/2018, 12:35
Poster
Elucidating water-to-ice freezing, especially in “No Man’s Land” (150 K < T < 235 K) is fundamentally important (e.g., predicting upper-troposphere cirrus-cloud formation) – and elusive. An oft-neglected aspect of tropospheric ice-crystallite formation lies in inevitably-present electric fields’ role. Exploring nucleation in No Man’s Land is technically demanding, owing to rapid nucleation...
Ms
Lucie Plaga
(TU Dortmund)
09/01/2018, 12:35
Poster
The crystalline ices can be divided into two groups, the hydrogen disordered and the hydrogen ordered ices. Phase transitions between ordered/disordered pairs that share the same oxygen lattice require the rearrangement of hydrogen bonds. These reorientational processes can only take place if point defects are present that locally violate the Bernal-Fowler ice rules, and the concentration of...
Frederic Flin
(Meteo-France CNRS / CNRM UMR 3589 / CEN), Dr
marie dumont
(Meteo-France - CNRS /CNRM/CEN)
09/01/2018, 12:35
Poster
Snow optical properties are unique among Earth surfaces and crucial for a wide range of applications. The bi-directional reflectance factor, hereafter BRF, of snow is sensible to snow microstructure. However the complex interplays between different parameters of snow microstructure, namely size and shape parameters, on reflectance are challenging to disentangle both theoretically and...
Prof.
Yoshimichi Hagiwara
(Kyoto Institute of Technology)
09/01/2018, 12:35
Poster
To develop icephobic surfaces is an urgent issue because ice-covering surfaces cause serious troubles, such as (1) poor visibility through the windshields of aircraft, trains and automobiles; (2) poor visibility of traffic lights in snowy winter, (3) the breaking of power transmission lines; (4) a deterioration of the aerodynamic performance of aircraft wings. To date, many studies proposed...
Dr
Vasily Artemov
(Prokhorov General physics institute of Russian academy of sciences)
09/01/2018, 12:35
PICO talk
Presently, the wideband dielectric spectra of water and ice are accumulated to be accessible for comparative analysis [1, 2]. The spectra reveal striking similarities such as a unified temperature dependence of the dielectric constants [3], related forms of dielectric relaxations (shifted by 6 decades on frequency) [4, 10], close matching of infrared resonances [6], abnormally high...
Dr
Jonathan Vermette
(Université de Sherbrooke)
09/01/2018, 12:35
Poster
Water nuclear spin isomers properties are of great interest for astrophysicists regarding information they can potentially provide from celestial ice bodies and interstellar cloud formation [1,2]. Population ratio between magnetic (H2O-ortho; Ms=1) and non-magnetic isomer (H2O-para; Ms=0) at equilibrium is a thermodynamic constant related to the nuclear spin temperature (Tspin). The very weak...
Mr
Balazs FABIAN
(Institut UTINAM - Besançon, France / ELTE Univ. of Budapest - Hungary), Dr
Sylvain PICAUD
(Institut UTINAM - UMR 6213 CNRS/Univ Franche Comte)
09/01/2018, 12:35
Poster
Overcoming the important deficiencies of the clathrate equilibrium data at low temperatures by using theoretical approaches such as the van der Waals & Platteeuw method seems truly tempting. However, this thermodynamic route is usually based on descriptions with simplified intermolecular potentials calibrated using equilibrium data obtained at high temperatures. As a consequence, the...
Andrey Stoporev
(Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk State University)
09/01/2018, 12:35
Poster
Experimental investigations carried out in this work allowed us to elucidate a number of new aspects in the ice freezing and gas hydrate formation processes in water-in-hydrocarbon emulsions. Various types of oils, including one with different biodegradation levels, and n-decane were used as disperse media. As it has been shown there are several hydrate and ice formation ways in the emulsions....
Ms
Annika Lauber
(ETH Zürich, IAC)
09/01/2018, 12:35
Poster
For a better understanding of cloud processes, accurate observations of ice crystal number concentrations and size spectra are important. We measure the cloud microphysics with the holographic imager HOLIMO. Holography is the only measurement technique, which allows the recording of the concentration, the size, the shape, as well as the spatial distribution of cloud particles. The...
Mr
John Ladan
(University of Toronto)
09/01/2018, 12:35
Poster
Icicles observed in nature and the laboratory often exhibit ribs or ripples with a wavelength close to 1cm around their circumference. Previous experiments on laboratory-grown icicles have shown that the existence of these ripples depends on the presence of (very small) concentrations of impurities in the feed water. However, all existing theoretical models of the icicle ripple instability...
Mr
Ryusuke Nishitani
(Department of Earth and Space Science, Graduate School of Science, Osaka University, Japan)
09/01/2018, 12:35
Poster
Clathrate hydrates are crystalline inclusion compounds composed of hydrogen-bonded water cages which incorporate hydrophobic gases called guest molecules. The clathrate hydrate could exist not only in the Earth but also in icy moons. One of the most likely candidate is Saturn's icy moon Enceladus, having a global ocean beneath the icy shell. INMS (Ion and Neutral Mass Spectrometer) aboard the...
Mr
Jaehyeock Bang
(Department of Chemistry, Seoul National University)
09/01/2018, 12:35
Poster
We studied the interaction of low energy (0-20 eV) electrons with sulfur dioxide (SO₂) on a crystalline ice film surface. An ice film was prepared by H2O vapor deposition on a Pt(111) substrate at 150 K for thickness of >100 BL inside a vacuum chamber and was annealed at 165 K to produce a crystalline ice film with a flat (0001) surface. SO₂ gas was adsorbed on the crystalline ice film through...
Frederic Flin
(Meteo-France CNRS / CNRM UMR 3589 / CEN)
09/01/2018, 12:35
Poster
Once deposited on the ground, snow forms a complex porous material whose microstructure constantly transforms over time. These evolutions, which strongly impact the physical and mechanical properties of snow (e.g. Srivastava et al, 2010; Calonne et al, 2014; Wautier et al, 2015) need to be considered in details for an accurate snowpack modeling. However, some of the physical mechanisms...
Mr
Jan Eichler
(Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research)
09/01/2018, 12:35
Poster
The impurity content in meteoric ice from polar regions is relatively low compared to other natural materials. However, it controls a variety of physical properties of ice - from dielectric response to its mechanical behaviour. Links between impurity concentration, changes in ice micro-structure and deformation rate have been reported on several scales. In order to approach the responsible...
Mr
Bastian Gerling
(WSL Institute for Snow and Avalanche Research SLF)
09/01/2018, 12:35
Poster
The elastic modulus is a fundamental mechanical property of snow and key for the interpretation of seismic measurements, assessment of slope stability or development of constitutive models. However, literature values scatter by orders of magnitude due to visco-plastic peculiarities of ice and microstructural variability. Hitherto still no cross-validated measurement exists.
To this end we...
Dr
Richard Gaal
(EPFL SB ICMP EPSL)
09/01/2018, 12:35
Poster
We report the results of Raman spectroscopy and quantum thermal bath molecular dynamics simulations in methane and hydrate at pressures up to 150 Gpa. We have found signatures of methane ordering, hydrogen bond symmetrisation and new high pressure phases.
Ms
Josée Maurais
(Département de chimie, Université de Sherbrooke, Sherbrooke, J1K 2R1, CANADA)
09/01/2018, 12:35
Poster
Mining residues tailings are a major environmental problem facing mining industries. These phenomena are a greater source of preoccupation during winter conditions since wind-borne dust emissions are less predictable; it is thus more difficult to prevent them. Also, mining residues tailings cause greater modulation of the albedo on permanently or seasonally snow-covered regions. Their...
Mr
Soroush Rasti
(Theoretical Chemistry, Leiden Institute of Chemistry, Leiden University)
09/01/2018, 12:35
PICO talk
Solid water comprises the most abundant form of ice in the universe and is believed to have played an important role in catalysing the formation of those prebiotic molecules that were essential for the development of life on earth. Apart from amorphous structures solid water also appears in a plethora of ordered structures under different temperature and pressure conditions. The corresponding...
Prof.
Bertrand Chazallon
(Laboratoire PhLAM, Bât. P5, UMR CNRS 8523, Université de Lille, 59655 Villeneuve d'Ascq, FRANCE)
09/01/2018, 12:35
Poster
Nitrogen-bearing clathrates, possibly mixed as gas hydrates also containing CO, H2, and CO2, are potentially important astrophysical constituents as they might take part in the formation of nebulae, comets and might have participated in the formation of the outer planets in the solar system.(1),(2)
The formation of clathrates in the solar system is often associated with vapor deposited...
Mrs
Shlomit Preis
(Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel.)
09/01/2018, 12:35
PICO talk
Spontaneous self-organization of a system can lead to pattern formation. Many examples for that are found in nature, such as dividing cells in the developing embryo, dendritic growth of crystals, and the formation of brine channels in sea ice. Here we present a new pattern formation in ice under selective infrared (IR) radiation. Unlike Tyndall flowers, which are dendritic melting of super...
Dr
Toshiaki Iitaka
(RIKEN)
09/01/2018, 12:35
Poster
Recently, Bove et al. (Phys. Rev. Lett. 103 165901) have found a supporting evidence for the existence of concerted proton tunneling along hydrogen bonds of six-membered rings in ice Ih using neutron incoherent quasi-elastic scattering measurement. Since the height of the potential barrier can be controlled by the distance between the nearest oxygen atoms or by the external pressure, study of...
Dr
Jennie Thomas
(LATMOS/IPSL, UPMC Univ. Paris 06 Sorbonne Universites, UVSQ, CNRS, Paris, France)
09/01/2018, 12:35
Poster
Black carbon (BC) concentrations has been observed in 22 snowpits sampled in the northwest sector of the Greenland ice sheet in April 2014. The pits contain a strong and widespread BC aerosol deposition event, which accumulated in the pits during two snow storms between 27 July and 2 August 2013. This event comprises a significant portion (57% on average across all pits) of total BC...
Dr
Lorenzo Ulivi
(IFAC-CNR)
09/01/2018, 12:35
PICO talk
Ice XVII is a newly discovered solid form of pure water, which is metastable at ambient pressure if maintained below 130 K. It is obtained from the so-called C0-phase of the H2-H2O binary compound, quenched at a temperature T=77 K, after letting the hydrogen molecules diffuse out of the crystal [1]. It is intrinsically porous and can absorb again molecular hydrogen and release it repetitively,...
Zuzana Sediva
(ETH Zurich)
09/01/2018, 12:35
Poster
CO2 gas hydrates are non-stoichiometric crystalline structures consisting of CO2 molecules entrapped in a 3D lattice of polyhedrals formed from water molecules. These structures, stable under moderate pressures and low temperatures, play a crucial role in in many environmental and energy sectors. Understanding and controlling the flow of hydrate slurries can bring rapid solutions for some...
Prof.
Changqing Sun
(NTU, SIngapore)
09/01/2018, 12:35
PICO talk
We show that transiting NaX/H2O solutions of 0.016 molar concentration (X = F, Cl, Br, I) [1, 2] and NaI/H2O of different concentrations into an ice VI phase and then into an ice VII at 298 K proceeding in different ways. The solute-type-resolved critical pressures PC1 and PC2 increases simultaneously in the Hofmeister series order: X = I > Br > Cl > F 0; comparatively,...
Mr
Hironobu Machida
(Panasonic Corporation)
09/01/2018, 12:35
Poster
Clathrate hydrate of tetra-n-butylammonium bromide (TBAB) is expected as a cold storage material for air conditioning, but supercooling is a problem for practical use. The supercooling, widely known, is the state of maintaining the liquid phase even if it is cooled below freezing point, but the detailed mechanism is not clarified. For the purpose of visualization of the supercooling...
Mr
Akimichi Kinjo
(Department of Applied Chemistry, Meiji University, Japan)
09/01/2018, 12:35
Poster
Water exists as amorphous ice in interstellar molecular clouds. Because molecules undergo chemical evolutions through various processes on amorphous ice, the structure and properties of amorphous ice is one of the important factors govern the chemical evolutions of organic molecules in the universe. Amorphous ice is formed by various methods; vapor deposition of water on cold substrates under...
Mr
Yasuhito Naoshima
(Department of Applied Chemistry, Meiji University, Japan)
09/01/2018, 12:35
Poster
Various gaseous species such as H2O, CO, CO2, CH3OH, H2CO, and NH3 are condensed onto dust grains in interstellar molecular clouds. The H2O ice, which is formed by vapor deposition onto the dust grains under low temperature and pressure conditions, is amorphous ice. The amorphous ice includes various gas molecules, and the molecules undergo chemical evolutions to organic molecules through...
Dr
Fei Yen
(Southern University of Science and Technology)
09/01/2018, 12:35
Poster
Many regions of the phase diagram of ice remain unclear. Through measurements of the near static dielectric constant a) the ice Ih/XI phase boundary line is confirmed to occur at 73 K along with the existence of the ice Ih/II/XI triple point residing at 0.07 GPa and 73 K [Phys. Chem. Chem. Phys. 2015, 17, 12458]; b) a critical point is identified to reside near 33-50 MPa and below 210 K...
Mr
Stefan Arzbacher
(Illwerke VKW Professorship for Energy Efficiency, Vorarlberg University of Applied Sciences)
09/01/2018, 12:35
PICO talk
Clathrate hydrates of CO2 are crystalline inclusion compounds composed of CO2 and water. They are expected to occur in vast amounts on comets, icy moons, and the Martian ice caps, where they play a significant role in the planetology. On earth, they are considered for usage in carbon capture and storage technologies due to their high mass density of CO2 [1,2].
Particularly, in the case of...
Andrey Stoporev
(Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk State University)
09/01/2018, 12:35
Poster
The structures of methane hydrate obtained from emulsions of water in some crude oils have been studied. It was shown that in some of these emulsions, a hydrate of the cubic structure II (sII) instead of the expected the cubic structure I (sI) hydrate was formed when a methane-saturated sample was rapidly cooled to temperatures below -35 °C. All experiments were carried out at a cooling rate...
Dr
Erik S. Thomson
(University of Gothenburg)
09/01/2018, 13:45
Nucleation
Talk
The phase state and role of aerosol particles in the radiative budget of the planet are important sources of uncertainty for climate modeling and prediction. The phase behavior of atmospheric particles depends on both environmental conditions and particle properties and can influence surface and bulk processes in both physical and chemical contexts. In the atmosphere soluble particulate is...
Prof.
Tianshu Li
(George Washington University)
09/01/2018, 14:05
Nucleation
Talk
Surface roughness has been long known to affect nucleation, but its role in ice formation remains controversial and poorly understood. Experiments showed ice nucleation is significantly promoted by surface irregularities on hematite, mica, and potassium-rich feldspar, but is relatively insensitive to the roughness of superhydrophobic surfaces.
By employing large-scale, accelerated...
Dr
Gabriele Cesare Sosso
(University of Warwick)
09/01/2018, 14:25
Nucleation
Talk
The formation of ice is one of the most ubiquitous examples of crystal nucleation and growth, affecting our everyday life as well as technologies such as cryotherapy [1] or fossil fuel extraction [2]. However, pure water freezes only when cooled about 30 K below its melting point [3]. Thus, ice on earth forms mostly heterogeneously, facilitated by substrates which lower the free energy cost...
Mr
Martin Fitzner
(Department of Physics and Thomas Young Centre, University College London)
09/01/2018, 14:45
Nucleation
Talk
The dynamical properties of liquid water play a role of great importance in the context of hydrophobic interactions, where the mobility of water molecules affects e.g. both the thermodynamics and the kinetics of ionic and proton transfer, as well as the mass diffusion of molecular species in aqueous environment. Not least, the ubiquitous phenomena of the glass transition and, as we argue in...
Prof.
Hinrich Grothe
(TU Wien)
09/01/2018, 15:05
Ice Binding Proteins
Talk
Aerosol-cloud interaction is an important part in understanding the Earth radiation balance and thus global climate. The IPCC indicates the level of understanding of this issue as rather low. This is particularly true for mixed phase clouds and ice clouds. In the recent past a broad variety of aerosols has been test for ice nucleation ability. However, there is still little knowledge about the...
Hendrik Bluhm
(Lawrence Berkeley National Laboratory)
09/01/2018, 16:55
keynote
Ice surfaces play a major role in many environmental processes and heterogeneous chemical reactions in the atmosphere. The properties of ice surfaces under environmental and atmospheric conditions, in particular the presence of a liquid-like layer at the ice surface at temperatures close to the melting point, are still far from being understood. For instance, reported thicknesses of the...
Dr
Ian Baker
(Dartmouth College)
10/01/2018, 10:00
keynote
In this presentation we give an overview of techniques used to characterize the microstructures of snow, firn (multi-year snow) and ice found in both cold regions and in polar ice sheets. These techniques include: transmission electron microscopy, synchrotron-based X-ray topography, cold-stage scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, electron channeling...
Mrs
Maurine Montagnat
(IGE - CNRS - UGA)
10/01/2018, 10:45
Mechanics & Microstructure
Talk
For some years now, Electron Backscattering Diffraction (EBSD) analysis has been applied to characterise, with high spatial and angular resolution the texture and microstructure of natural ice samples [Obbard et al. J. Glaciol. 2006], or artificially deformed samples [e.g. Piazolo et al. J. Microscopy 2008, Weikusat et al. J. Microscopy 2011]. Contrary to classical optical measurements...
Mr
Sven Erik Avak
(Laboratory of Environmental Chemistry, Paul Scherrer Institute, Switzerland)
10/01/2018, 11:05
Mechanics & Microstructure
Talk
Past changes in atmospheric pollution can be reconstructed from high-alpine ice core trace element records (Schwikowski et al., 2004). Eichler et al. (2001) suggested that the preservation of major ions with respect to meltwater percolation depends on their location in the ice crystal lattice. Species predominately segregated at grain surfaces during snow metamorphism were more efficient...
Dr
Sønke Maus
(Norwegian University of Science and Technology (NTNU))
10/01/2018, 11:25
Ice Crystal Growth
Talk
When columnar sea ice forms on seawater by unidirectional freezing its interface is known to have a lammelar microstructure, consisting of vertically oriented plates with largely horizontal c-axis orientation, parallel within each grain. Away from the interface these plates thicken by lateral freezing, driven by (i) a decrease in temperature and (ii) intermittent convective exchange of brine...
Mr
Jürg Trachsel
(WSL Institute for Snow and Avalanche Research SLF)
10/01/2018, 11:45
Mechanics & Microstructure
Talk
Impurity records of an ice core are used as a proxy for past climate change. However, the processes leading to the embedding of chemical compounds are not completely understood: The compounds from the atmosphere are deposited on the ground during snowfall. If the snow does not completely melt, like on polar and alpine glaciers, the impurities will be preserved in the snowpack and later...
Prof.
Jan B. C. Pettersson
(University of Gothenburg)
10/01/2018, 17:05
keynote
Ice nucleation research is currently booming and much of the attention is motivated by the need to improve the description of aerosol and cloud processes in the atmosphere. The formation of clouds has important effects on the water cycle on Earth and on the radiation budget of the atmosphere. The formation of liquid cloud droplets is comparatively well described by existing theory, while the...
Ellen Backus
(Max Planck Institute for Polymer Research)
10/01/2018, 17:50
The surface and interface of ice
Talk
Over 150 years ago, Faraday proposed the existence of a liquid-like layer at ice surfaces below the bulk melting temperature. This layer is important for surface chemistry and glacier sliding close to sub-freezing conditions. Since Faraday’s discovery, the properties of this water-like layer have been intensely debated, entailing considerable controversy. The experimentally reported onset...
Dr
Sylvain PICAUD
(Institut UTINAM - UMR 6213 CNRS/Univ Franche Comte)
10/01/2018, 18:10
The adsorption of all the fluorinated and chlorinated methane derivatives at the surface of Ih ice is studied by grand canonical Monte Carlo simulations at 200 K.
The adsorption isotherms are simulated and their shape is discussed in terms of the interplay of adhesive and cohesive interactions. It is found that in cases when the adhesive interaction is
clearly the stronger one, multilayer...
Thorsten Bartels-Rausch
(Paul Scherrer Institut)
10/01/2018, 18:10
Tropospheric ozone depletion events (ODEs) via halogen activation are observed in both cold and warm climates [1-3]. Very recently, it was suggested that this multiphase halogen activation chemistry is the dominates in the tropical and subtropical upper troposphere. These occurrences beg the question of temperature dependence of halogen activation in sea-salt aerosol, which are often mixtures...
Thorsten Bartels-Rausch
(Paul Scherrer Institut)
10/01/2018, 18:10
The pre-melting at the surface of ice crystals in surface snow or ice clouds has been proposed to explain a number of large-scale environmental effects ranging from electrification of thunder clouds and the scavenging of atmospheric trace gases to the flow of glaciers1. There is now general agreement on the appearance of this quasi-liquid layer (QLL) when temperatures approach the melting...
Dr
KITAE KIM
(Korea Polar Research institute(KOPRI))
10/01/2018, 18:10
Ice is one of the simplest crystalline materials on earth and plays various important roles on earth environmental system. Although enormous progress has been made in understanding on physics and chemistry of ice, we have still a large number of mysterious features on ice. In most cases, chemical reactions take place slowly when temperature drops according to Arrhenius Equation. However,...
Mr
Jialu Chen
(Institute of Low Temperature Science, Hokkaido University)
10/01/2018, 18:10
Surface melting of ice occurs below 0°C, and then ice surfaces are covered with quasi-liquid layers (QLLs). Our previous studies revealed that QLLs are formed kinetically on ice single crystals only in the temperature range higher than -2°C [1, 2]. However, other studies reported the appearances of QLLs even below -10°C [3]. To clarify the cause for this big discrepancy, in this study we...
Prof.
Yoshimichi Hagiwara
(Kyoto Institute of Technology)
10/01/2018, 18:10
The growth of frost crystals and frost layers on solid surfaces causes serious troubles, such as poor visibility through automobile windshields and a deterioration of the performance of heat exchanger in the air. Thus, the growth controls of frost crystals and frost layers are very important for reducing these troubles. Many experiments for these controls have been conducted using grooved...
Dr
Hailong Li
(Max Planck Institute for Polymer Research)
10/01/2018, 18:10
Material properties of ground ice and permafrost strongly depend on the molecular scale structure and dynamics of the quasi-liquid premelting layer (qll) formed at ice/solid interfaces. Already in 1859, Faraday proposed the existence of a qll at ice surfaces. However, despite the extensive amount of research devoted to the understanding of interfacial ice melting, the structure of the qll...
Mr
Johannes Kirschner
(AMOLF)
10/01/2018, 18:10
The properties of small organic molecules at the ice/air interface are crucial for the understanding of fundamental processes in fields spanning from molecular physics to chemistry in the stratosphere. Here we use surface-specific heterodyne-detected vibrational sum-frequency generation spectroscopy (HD-VSFG) to investigate the molecular properties of ethanol at the air-water and the...
Mr
Norifumi Hara
(Department of Applied Chemistry, Meiji University, Japan)
10/01/2018, 18:10
In interstellar molecular clouds, various molecules (for instance, H2O, NH3, CO, CO2, and so on) are formed from elements such as H, C, O, and N [1]. Most of H2O exists as a thin shell of amorphous ice around dust grain. The molecules undergo chemical evolutions to organic molecules through various processes on the surface of amorphous ice [2]. Thus, the surface structure of amorphous ice is...
Dr
Michel J. ROSSI
(Paul Scherrer Institute (PSI))
10/01/2018, 18:10
Experiments have been performed using a multidiagnostic stirred-flow reactor (SFR) in which the gas- as well as the condensed phase have been simultaneously investigated under stratospheric temperatures in the range 175-200 K. Wall interactions of the title compounds have been taken into account using Langmuir adsorption isotherms in order to close the mass balance between deposited and...
Mr
Tadashi Kaijima
(Kyoto Institute of Technology)
10/01/2018, 18:10
The inhibition of ice growth is an important issue in various fields, such as the maintenance of the quality of food texture in food preservation, and cryosurgery. Antifreeze protein (AFP) and antifreeze glycoprotein (AFGP) have been investigated in relation to the inhibition of ice growth. This is because the AF(G)P solutions have the following properties: (a) the freezing point drops...
Prof.
Cheol Ho Choi
(Kyungpook National University)
10/01/2018, 18:10
With the help of our QM/EFP scheme, the adsorptions of Na+, F-, Br- and Cl- ions on Ih ice surface were theoretically studied. Drastically different adsorption behaviors depending on ion signs and surface heterogeneity were observed. The positive Na+ ion forms 4 ~ 5 Na+-O interfacial bondings regardless of the numbers of hydrogen dangling bonds (HDB), yielding consistent adsorptions with large...
Dr
Alexei Kiselev
(Karlsruhe Institute of Technology, Institute of Meteorology and Climate Research)
10/01/2018, 18:10
We report measurements of growth rates of ice crystals that were nucleating on feldspar mineral substrates in the environmental scanning electron microscope (ESEM) filled with the mixture of nitrogen and water vapor [3]. The linear growth velocity of prismatic and basal faces of ice crystals has been estimated from the sequence of individual ESEM frames recorded every second. Using the...
Dr
Jenee Cyran
(Max Planck Institute for Polymer Research)
10/01/2018, 18:10
Ice has significant effects on the climate and biogeochemical systems and plays a role in reactions known to contribute to ozone depletion and atmospheric pollution. Long range transport of hazardous pollutants, such as polycyclic aromatic hydrocarbons (PAHs), on ice contributes to the disruption of these biogeochemical systems. PAHs and their derivatives from photolysis are known to be...
Mr
Masahiro Inomata
(Institute of Low Temperature Science, Hokkaido University)
10/01/2018, 18:10
Ice is one of the most abundant materials on the earth. Hence, crystal growth of ice governs a wide variety of phenomena in nature. For example, most rains fallen outside tropical regions are formed by the melting of ice crystals (snowflakes) that were grown in the sky and then descended to the ground [1]. Therefore, to understand the growth kinetics of ice crystals is extremely important....
Dr
Jennie Thomas
(LATMOS/UCLA)
10/01/2018, 18:10
The cold regions on Earth are undergoing significant climate change. Yet many underlying chemical, biological, and physical processes and feedbacks are still poorly understood strongly motivating continued research in cold regions. Such research inherently requires cooperation among researchers and programs across national boundaries to achieve science objectives. CATCH is an emerging activity...
Dr
Ian Baker
(Dartmouth College)
10/01/2018, 18:10
It is well established that the Earth’s large continental ice sheets contain a variety of naturally occurring impurities, both soluble and insoluble. Understanding how these impurities affect the rheology, intrinsic thermodynamic properties, and fate of these ice sheets is much less understood. To investigate the effects that trace amounts of H2SO4 have on the flow and ductility of...
Mr
Mario Nachbar
(Institute of Environmental Physics, University of Heidelberg)
10/01/2018, 18:10
Heterogeneous H2O nucleation studies below 150K are rare, but important to understand the formation of cold ice clouds in terrestrial atmospheres, e.g. polar mesospheric clouds on Earth or water ice clouds on Mars. We use a time-of-flight mass spectrometer to study H2O adsorption, critical saturation and subsequent growth on sub 4nm iron oxide and silica particles levitated in a modified ion...
Dr
Denis Duft
(Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany)
10/01/2018, 18:10
It is known that at ambient pressure the crystallization of amorphous ices proceeds via the formation of nano-crystallites. This fact, however, is not considered in many studies on amorphous and crystalline ices formed from the amorphous phase even though it has important implications on various ice properties. As an example, we show in this contribution, that the saturation vapor pressure...
156.
Towards the surface science of ice nucleation on aqueous organic solutions and solid substrates
Mr
HUANYU YANG
(Paul Scherrer Institut)
10/01/2018, 18:10
The nucleation of ice is an important process in chemistry, physics and atmospheric science. Although ice nucleation has been studied since long, our understanding of ice nucleation is still far from complete, particularly from a molecular point of view. The hydrogen bonding structure of H2O ice can be significantly different between liquid water to ice, which is responsible for most of the...
Dr
Sønke Maus
(Norwegian University of Science and Technology (NTNU))
10/01/2018, 18:10
Percolation theory describes the properties of a large number of objects related to their connectivity. The spreading of fluid through a porous medium is, among other applications, a percolation process that was first described by Broadbent and Hammersley (1) in terms of percolation theory. During the past decades this theory has been formulated and many different applications, like forest...
Ms
Prerna Sudera
(PhD student)
10/01/2018, 18:10
The surface of ice is relevant for various important phenomena including glacier sliding, and (photo-) chemical conversion of molecules on that surface.
For chemical reactions occurring on the ice surface, the dynamics of the surface water molecules and energy flow pathways play an important role: following a chemical reaction, the rate of excess energy dissipation determines the...
Dr
Ken-ichiro Murata
(Institute of Low Temperature Science, Hokkaido University)
11/01/2018, 08:35
The surface and interface of ice
Talk
Ice crystallization from supercooled water, more generally, crystallization from its own supercooled melt (the so-called melt growth), is one of the fundamental phase transitions seen everywhere in nature. Despite its ubiquity, the microscopic view of the melt growth is still far from completely understood, contrary to the crystal growth from vapor and solutions. It is well-known that the...
Prof.
Yoshimichi Hagiwara
(Kyoto Institute of Technology)
11/01/2018, 08:55
The surface and interface of ice
Talk
The formation of ice layer by water droplets on surfaces causes many troubles, such as poor visibility through the windshields of aircraft, trains and automobiles; the breaking of power transmission lines; a deterioration of the aerodynamic performance of aircraft wings. Thus, many studies have been carried out. However, the details of heat transfer during the freezing have not yet been...
Prof.
John Wettlaufer
(Yale University)
11/01/2018, 09:15
The surface and interface of ice
Talk
We examine the effects of confinement on the dynamics of premelted films driven by thermomolecular pressure gradients. Our approach is to modify a well-studied setting in which the thermomolecular pressure gradient is driven by a temperature gradient parallel to an interfacially premelted elastic wall. The modification treats the increase in viscosity associated with the thinning of films,...
Prof.
Markus Mezger
(Max Planck Institute for Polymer Research)
11/01/2018, 09:35
The surface and interface of ice
Talk
At ice/solid interfaces, a quasi-liquid premelting layer (qll) is formed at temperatures below the melting point of bulk water. This qll affects the properties of ice/clay nanocomposites found in ground ice and permafrost. One of the decisive parameters is the water mobility within the qll. Using quasi elastic neutron scattering, the translational diffusion constant of the qll was studied for...
Dr
Ted Hullar
(University of California at Davis)
11/01/2018, 10:30
Thorsten Bartels-Rausch
(Paul Scherrer Institut)
11/01/2018, 10:50
Chemistry
Talk
Earth’s surface snow plays an active part in atmospheric chemistry. Research over the past decades has provided an impressive observational basis of the resulting large scale effects, such as substantial modification of the composition and of the chemical reactivity of the lowermost atmosphere in polar regions.
Here, I present details on the chemical mechanisms operating in environmental...
Dr
Ted Hullar
(University of California at Davis)
11/01/2018, 11:10
Chemistry
Talk
Chemical compounds can be incorporated into snow crystals during formation, for example by co-deposition with water vapor, or after the crystal is formed, such as by vapor deposition onto the surface of the crystal. As fallen snow crystals consolidate in a snowpack, entrained compounds can remain at the ice-air interface of the snowpack (i.e., in the quasi-liquid layer (QLL) of the disordered...
Prof.
Patrick Ayotte
(Université de Sherbrooke)
11/01/2018, 11:30
Chemistry
Talk
A thermodynamically reversible path was suggested to exist linking the low density forms of amorphous ice (LDA) and deeply supercooled liquid water (LDL), through the so-called no man’s land and finally onto normal liquid water.(1) Furthermore, at temperatures below its calorimetric glass transition temperature (Tg ~ 136K), transport kinetics are exceedingly slow in amorphous solid water...
Prof.
Heon Kang
(Seoul National University)
11/01/2018, 11:50
Talk
We studied the ionic dissociation of trifluoroacetic acid (TFA) in amorphous solid water (ASW) using reflection absorption infrared spectroscopy, low energy sputtering, and H/D isotopic exchange experiment. TFA readily dissociated to hydronium and counter ions in ASW at 60 K, which indicates a significant increase of the acidity as compared to that in aqueous solution at room temperature. The...
Dr
Thomas Douglas
(Cold Regions Research and Engineering Laboratory)
11/01/2018, 12:10
Fundamentals of the Cryosphere
Talk
Mercury is deposited to polar snow and ice surfaces during springtime atmospheric mercury depletion events (AMDEs). AMDEs require sunlight, frozen surfaces, and a reactive bromine source such as sea ice or halogen-rich snow. During these events gaseous elemental mercury (Hg0; GEM) is oxidized to reactive gaseous mercury (HgII; RGM) which can associate with particles to form particulate Hg...
Prof.
Ido Braslavsky
(The Hebrew University of Jerusalem)
11/01/2018, 13:55
keynote
We investigate the interactions of ice-binding proteins, IBPs, with ice surfaces. In particular, we investigate the dynamic nature of the protein&ice interaction using fluorescence microscopy techniques combined with temperature-controlled microfluidic devices. The results show that binding of IBP to ice is irreversible and that the freezing temperature depression is sensitive to the time...
Dr
Dominik Heger
(Masaryk Univerity)
11/01/2018, 14:40
Ice Binding Proteins
Talk
The freezing of aqueous solutions leads to the separation of ice crystals and the remaining solutes into microscopic veins and pockets; these regions are known as the freeze concentrated solution (FCS). The interactions between the molecules present within this phase are of key importance for the stability or reactivity of compounds in both natural and human-controlled freezing. Pharmaceutic...
Dr
Maddalena Bayer-Giraldi
(Alfred-Wegener-Institute Bremerhaven (Germany))
11/01/2018, 15:00
Ice Binding Proteins
Talk
Ice-binding proteins (IBPs), produced by polar and cold-tolerant organisms, have the ability to bind to ice, affecting its growth. They are key elements in biological adaptation to cold environments, and no other particles, neither natural nor synthetic, show comparable effect in controlling ice growth. However, the details of the protein-ice interactions have not been clarified yet. Different...
Prof.
Alexander Bittner
(CIC nanogune)
11/01/2018, 15:20
Ice Binding Proteins
Talk
Assembled proteins, esp. cages and viruses, are essential ingredients of life [Calo 2016a]. Some assemblies appear to tolerate the contact to ice, or even the growth of ice. While the interaction of single proteins or simple biopolymers with ice is increasingly investigated [Hiranuma 2015], assemblies are new territory [Wilson 2015]. We pose two questions:
1. Molecular geometry: Is there...
Dr
Konrad Meister
(AMOLF)
11/01/2018, 15:40
Ice Binding Proteins
Talk
Antifreeze proteins (AFPs) and Antifreeze Glycoproteins (AFGPs) collectively abbreviated as AF(G)Ps are a unique class of proteins that modify ice crystal growth and thereby ensure the survival of organism in freezing and subfreezing habitats. The molecular working mechanism behind AF(G)Ps freezing inhibition is not well understood, because, as yet, there are no experimental techniques that...
Dr
Andrew Wells
(University of Oxford)
11/01/2018, 16:35
keynote
More than 20 million square kilometres of the polar oceans freeze over each year to form sea ice. Sea ice is a mushy layer: a reactive, porous, multiphase material consisting of ice crystals bathed in liquid brine. The porosity of sea ice evolves in space and time, with important consequences for coupling to the oceans and sea ice ecosystems. Atmospheric cooling generates a density gradient in...
Dr
Odile Crabeck
(University of manitoba)
11/01/2018, 17:20
Fundamentals of the Cryosphere
Talk
Past and recent literature have highlighted that sea ice might play a crucial role in controlling and contributing to the exchange of significant climatically active biogases between the ocean and the atmosphere in polar areas. However, the formation of air inclusions and the transport of gases within sea ice cover are still poorly understood. In it is pure form sea ice is a multi-phase system...
Mr
Rémi Granger
(Univ. Grenoble Alpes, CNRS, Grenoble INP, 3SR / Météo-France CNRS/ CNRM UMR 3589/ CEN)
11/01/2018, 17:40
Fundamentals of the Cryosphere
Talk
Temperature gradient metamorphism of snow is a mechanism of snowpack transformation resulting from the coupling of elementary physical processes: heat conduction, vapour transport in the pore space and phase change at the ice/air interface. An important feature of this mechanism is that it produces a faceted microstructure with sufficiently strong gradient, as a consequence of the anisotropy...
Prof.
Stephen Warren
(University of Washington)
12/01/2018, 08:35
keynote
Radiative properties of ice, and of ice-containing media such as snow and clouds, are determined by ice's refractive index and absorption coefficient (“optical constants”). The dominant absorption mechanisms are electronic in the ultraviolet and visible, molecular vibration in the near-infrared, (hindered) rotation in the thermal IR, and lattice translations in the far-IR.
The molecular...
Dr
Henning Löwe
(WSL Institute for Snow and Avalanche Research SLF)
12/01/2018, 09:20
Mechanics & Microstructure
Talk
It is well known that the mechanical behavior of snow highly depends on strain-rate as a consequence of the visco-plastic nature of ice. Accordingly, the mechanical response of snow is commonly believed to undergo a single transition from ductile to brittle behavior at a critical strain rate. A recent analysis of snow compression has however revealed the relevance of another time-scale...
Ms
Sigrid Rønneberg
(Norwegian University of Science and Technology)
12/01/2018, 09:40
Fundamentals of the Cryosphere
Talk
Ice formation is unavoidable at low temperatures. Ice and frost cause not only inconvenience but also danger in the daily life of human beings, especially in cold regions. For example, ice accumulation on roads or on aircraft wings causes accidents and ice accumulation on wind turbines or overhead power lines can affect the distribution of electricity, power losses and mechanical and...
Prof.
Ian Hewitt
(University of Oxford)
12/01/2018, 10:35
Fundamentals of the Cryosphere
keynote
The movement of continental and mountain-scale ice masses is usually modelled as a problem of viscous creep. The viscosity arises from temperature- and stress-dependent migration of defects through the polycrystalline structure of the ice, and the rheology is usually described as a power law fluid for the purposes of large-scale ice-sheet models. Much of the ice motion arises from effective...
Ms
Veronika Emetc
(Research School of Earth Sciences, Australian National University)
12/01/2018, 11:20
Fundamentals of the Cryosphere
Talk
Creating an effective model of the calving process in Antarctica is a challenging task in ice sheet modelling.
The recent calving of Larsen B and Larsen C ice shelves has raised a number of questions as to the nature of the key factors that triggered these calving events and whether they are caused by natural ice sheet dynamics or climate change. To address this, a reliable calving model...
Mr
Jörg Wieder
(Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, 8092, Switzerland)
12/01/2018, 11:40
Fundamentals of the Cryosphere
Talk
Mixed-phase clouds (MPCs), composed of both liquid droplets and ice crystals, play a crucial role in the global radiation budget. Yet, a reliable detection of liquid and ice cloud fraction remains difficult. This in turn hinders a complete understanding of the complex microphysical processes that occur within these clouds, and ultimately renders estimation of the radiative properties of MPCs...
