Ice model

The thin ice model the silicates are mainly hydrated, so there is a thin layer (a few kilometres) of water ice above the silicates. 

The thick ice model enough heat was generated in the interior of the moon to dehydrate the silicates. The water set free froze to give an ice layer about 100 km thick. 

The model includes a dynamic thermodynamic sea ice model. The dynamics of sea ice are formulated using viscous-plastic rheology [Hibler (1979)]. The thermodynamics relate changes in sea ice thickness to a balance of radiant, turbulent, and oceanic heat fluxes. The effect of snow accumulation on sea ice is included, along... 

Sea ice is represented in the model as a two-dimensional surface covered with a snowpack. Ice advection, rheology and snow cover are calculated from the sea-ice model embedded in MPIOM [Hibler (1979)]. The only source of pollutants for the ice compartment is deposition from the atmosphere. Once pollutants enter the ice compartment they can diffuse into the snow pore space air, dissolve in the interstitial liquid water or adsorb to the ice surface. Together with the sea ice the pollutants undergo advection. Sinks considered for the ice compartment are volatilisation to the atmosphere and release into the ocean with melt water. 

Artificial hydrothermal vents might be constructed and supplied with plausible concentrations of simple reactants such as CO, H2, NH3, and H2S. Appropriate levels of amino adds induding a small chiral excess, along with the sorts of amphiphilic molecules described above, can be rationalized by the findings from the Murchison meteorite. Organic molecules such as found in irradiated interstellar ice models, including HMT, can also be induded. The system should indude weathered feldspars, which can be modified to indude the reduced transition-metal minerals that they are known to contain. [134] Such minerals as Fe,Ni sulfides are likely to have been both present and stable in the environment of early Earth and are known [153, 155] to catalyze formation of organic molecules from simpler precursors. 

Concerning ices, it has been discussed that they must be amorphous (Smoluchowski 1983) in the interstellar medium and not crystalline. This implies that the adsorbed H atoms are localized in deep traps so that their wavefunctions have a limited spatial extent. This fact reduces significantly their mobility and hence the interaction with another H atom absorbed on another site is slow as compared to the residence time unless the two atoms happens to be localized near each other. This phenomenon reduces the rate of H2 formation by several orders of magnitude when compared to the situation on crystalline surfaces. Computational simulations on soft and hard ice model surfaces have shown that for a cross-section of 4,000 nm2 the reaction probability is 1 (Takahashi et al. 1999). Furthermore, the H2 formed, due to the high amount of energy liberated is rapidly desorbed in an excited state from the ice mantle in timescales of 500 fs (Takahashi et al. 1999). 

Keywords hydrogen accumulator, hydrated methane, polymorphism, phase transition, nanostructure of ice, modeling... 

In applications such as the Arctic sea ice model (Chapman et al., 1994) mentioned above, a strategic objective of a preliminary computer experiment is screening finding the important input variables. Screening is not a trivial task because the computer model is typically complex, and the relationships between input variables and output variables are not obvious. A common approach is to approximate the relationship by a statistical surrogate model, which is easier to explore. This is particularly useful when there are many input variables. 

All these studies provide evidence for a rich radiation chemistry. For example, in N2-dominated ice (modeling the surfaces of Pluto and Triton, a moon of Neptune), the authors have proven by infrared spectroscopy the formation of HCN as well as HNC starting from N2/CH and N2/CH /CO mixtures. Other species such as HNCO, NH3, NH4, OCN , CN and N3 were also detected. As many of these species are involved in reactions producing biomolecules (amino acids, polypeptides), these results suggest the possibility of an interesting prebiotic chemistry on Triton and Pluto. 

NCAR (1997). The NCAR Community Climate Model CCM3 with NCAR/CSM Sea Ice Model. University Corporation for Atmospheric Research, National Center for Atmospheric Reseeu-ch, and Climate and Global Dynamics Division, http //www.cgd.ucar.edu 80/ccr/bettge/ice. 

Presumably, as with Callisto and Ganymede, the crust and mantle are primarily water ice. Models of the atmospheric chemistry however suggest that the surface should receive a continual rain of hydrocarbon aerosols, some of which may be liquid under Titan surface conditions (Lunine, 1993 Lunine et ai, 1983). 

The horizontal ice distribution simulated with such a low order ice model resembles the observed distributions of sea ice however, the storage of freshwater in the ice and the formation of a new water mass by freezing with brine release and by melting is neglected. To include these features, the three-level ice model of Winton (2000) is coupled with MOM-3.1 to provide an improved representation of sea ice for long-term simulations. The sea ice is vertically resolved by two ice layers and a snow cover, with different development of thickness and temperature. As shown in Fig. 19.3, this local thermodynamic description yields arealistic simulation of the interannual variation in the thickness and the spatial extent of the ice cover in the Baltic Sea. The transfer of wind momentum to the currents and to surface waves is exponentially damped out if the ice thickness exceeds a critical value, for example, 10 cm, assuming fast ice. 

As described in Section 19.2.3.8, regional models, such as a Baltic Sea model, can get the boundary values for the calculation of surface fluxes from simulations with atmosphere models, which have been carried out previously. This is possible, because the influence of the Baltic Sea on the Northern Hemisphere weather system is only important for local phenomena, and inaccuracy in the feedback from the Baltic Sea to the atmosphere is of minor importance, Schrumm and Backhaus (1999). Widely used datasets, such as the ERA-40 reanalysis data, are improved by assimilation of observations. If surface variables calculated by the ocean model tend to drift away, this is compensated to a large extent by the calculated surface fluxes. For this reason numerical simulations with standalone ocean-ice models can be successful. 

Winton, M., 2000. A reformulated three-layer sea ice model. Journal of Atmospheric and Oceanic, Technology, 17 (4), 525-531. 

A number of arguments can be made in favor of cometary carriers for inner planet volatiles. As noted above, reduction of the Ne/Ar ratio relative to the solar ratio, resembling the elemental pattern on Venus, is likely in such ices. Modeling discussed below indicates that a source of this nature could have supplied essentially identical primary atmospheres to both Venus and Earth if an initially Venus-like atmosphere on Earth were later elementally fractionated in hydrodynamic escape powered by a giant Moon-forming impact. 

For a two-dimensional square lattice (z=4), FH theory gives o>h = 1 104. The upper bound can be estimated by using ice model [22] to be h = (4/3) / = 1.5396. Numerical simulation evaluates o>h = 1.38. The estimate of the lower bound is possible by using the model of the Manhattan walk [23]. The Manhattan walk is a Hamilton walk on the directed lattice. Walks have to follow the arrows on the edges, which are alternately up/down and left/right, as the traffic regulation in Manhattan downtown. 

Hals, T. Jenssen, N.A. DP Ice Model Test Of Arctic Eirillship and Polar Research Vessel. ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering, 2012. American Society of Mechanical Engineers, 467-472. 

The protein-ice modeling was conducted using the averaged simulation protein structure on the (100) ice plane. The protein was manually docked with the C-face of the Type III antifreeze protein on the (100) ice surface. This particular face of ice was chosen because of the three conseiwed residues (N14, T18, and Q44) which have been identified through mutation studies as being crucial for... 

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