scholarly journals Mathematical modeling of temperature changes impact on artificial ice islands

2021 ◽  
Vol 13 (1) ◽  
pp. 79-86
Author(s):  
Maxim V. Muratov ◽  
◽  
Vladimir A. Biryukov ◽  
Denis S. Konov ◽  
Igor B. Petrov ◽  
...  

The article is devoted to the numerical solution of the Stefan problem for thermal effects on an artificial ice island. For modern tasks of the development of the Arctic, associated with the exploration and production of minerals, it is important to create artificial ice islands in the Arctic shelf, due to the speed of their construction, economic feasibility and other factors. The most important task for the exploitation of such islands is their stability, including against melting. This paper discusses the issue of the stability of ice islands to melting. For this, the Stefan problem on the change in the phase state of matter is formulated. An enthalpy solution method is constructed, and the applicability of this method is considered. For the numerical solution, the Peasman-Reckford scheme is used, which is unconditionally spectrally stable in the two-dimensional case, which allows to freely choose the time step. In addition, the developed approach takes into account the flow of water and the flow of melted water, which is important in the task at hand. The developed computational algorithms are parallelized for use on modern multiprocessor computing systems An approach is implemented for modeling thermal processes in the thickness of an arbitrary mass of substances, taking into account arbitrary initial conditions, environmental conditions, tidal currents of water, and solar radiation. This approach was used to calculate the temperature distribution in the thickness of the ice island, as well as to study the impact of seasonal temperature changes on the stability of the island.

2009 ◽  
Vol 22 (23) ◽  
pp. 6168-6180 ◽  
Author(s):  
A. G. Marshall ◽  
A. A. Scaife ◽  
S. Ineson

Abstract The impact of explosive volcanic eruptions on the atmospheric circulation at high northern latitudes is assessed in two versions of the Met Office Hadley Centre’s atmospheric climate model. The standard version of the model extends to an altitude of around 40 km, while the extended version has enhanced stratospheric resolution and reaches 85-km altitude. Seasonal hindcasts initialized on 1 December produce a strengthening of the winter polar vortex and anomalous warming over northern Europe characteristic of the positive phase of the Arctic Oscillation (AO) when forced with volcanic aerosol following the 1963 Mount Agung, 1982 El Chichón, and 1991 Mount Pinatubo eruptions, as is observed. The AO signal in the extended model is of comparable strength to that in the standard model, showing that there is little impact from both increasing the vertical resolution in the stratosphere and extending the model domain to near the mesopause. The presence of this signal in the models, however, is likely due to the persistence of the observed signal from the initial conditions, because a similar set of experiments initiated with the same conditions, but with no volcanic aerosol forcing, exhibits a similar response as the forced runs. This suggests that the model has limited fidelity in capturing the response to volcanic aerosols on its own, consistent with previous studies on the impact of volcanic forcing in long climate simulations, but does support the premise that seasonal winter forecasts are substantially improved with the inclusion of stratospheric information.


2020 ◽  
Author(s):  
Brian Moorman

<p><span>Around the Arctic Ocean there are many stretches of coastline composed of ice-rich sediments. With the dramatic climatic, oceanic and terrestrial changes that are currently occurring, there is considerable concern over the stability of these coasts and how they are being altered. With the complexity that permafrost conditions add to the coastal setting, modelling erosion involves a more detailed understanding of the physical and thermal conditions as well as the sedimentological and wave action processes. This research examines the role that the shallow water energy balance plays in preserving sub-bottom massive ice as the coastline retreats and the implications it has for secondary subsea disturbance once the water depth increases.</span></p><p><span>The study area was Peninsula Point which is approximately 10 km west of Tuktoyaktuk, NWT, Canada. The massive ice and retrogressive thaw slumps at this location are some of the more dramatic examples of the impact of ice-rich permafrost on coastal processes in the Arctic. By mapping the area with satellite and aerial imagery and conducting repeat ground penetrating radar surveys (GPR) over a 30 year period, the long-term character of coastal retreat above, and below, the water line is revealed. In winter, the GPR was pulled behind a snowmobile along transects on land, across the shoreline and out onto the near shore area of the Beaufort Sea. This provided the stratigraphic continuity between the terrestrial and sub-sea settings. The GPR revealed the massive ice and sedimentary architecture, from which vertical and lateral relationships to the coastline were determined. The roles of erosion, re-sedimentation and shallow-water thermodynamics in the degradation and preservation of massive ground ice were revealed. Using this new information, modeling of the coastal retreat and sediment contributions to the ocean demonstrated a much more complex system than previously assumed.</span></p>


2015 ◽  
Vol 143 (10) ◽  
pp. 4012-4037 ◽  
Author(s):  
Colin M. Zarzycki ◽  
Christiane Jablonowski

Abstract Tropical cyclone (TC) forecasts at 14-km horizontal resolution (0.125°) are completed using variable-resolution (V-R) grids within the Community Atmosphere Model (CAM). Forecasts are integrated twice daily from 1 August to 31 October for both 2012 and 2013, with a high-resolution nest centered over the North Atlantic and eastern Pacific Ocean basins. Using the CAM version 5 (CAM5) physical parameterization package, regional refinement is shown to significantly increase TC track forecast skill relative to unrefined grids (55 km, 0.5°). For typical TC forecast integration periods (approximately 1 week), V-R forecasts are able to nearly identically reproduce the flow field of a globally uniform high-resolution forecast. Simulated intensity is generally too strong for forecasts beyond 72 h. This intensity bias is robust regardless of whether the forecast is forced with observed or climatological sea surface temperatures and is not significantly mitigated in a suite of sensitivity simulations aimed at investigating the impact of model time step and CAM’s deep convection parameterization. Replacing components of the default physics with Cloud Layers Unified by Binormals (CLUBB) produces a statistically significant improvement in forecast intensity at longer lead times, although significant structural differences in forecasted TCs exist. CAM forecasts the recurvature of Hurricane Sandy into the northeastern United States 60 h earlier than the Global Forecast System (GFS) model using identical initial conditions, demonstrating the sensitivity of TC forecasts to model configuration. Computational costs associated with V-R simulations are dramatically decreased relative to globally uniform high-resolution simulations, demonstrating that variable-resolution techniques are a promising tool for future numerical weather prediction applications.


Author(s):  
A. E. Cherepovitsyn ◽  
◽  
D. M. Metkin ◽  

The Arctic zone of the Russian Federation (AZRF) is characterized by the fragility of the ecosystem, the slightest violation of which can lead to catastrophic negative consequences on a global scale. Due to the availability of production facilities of various scales and environmental safety classes within the territorial and aquatic Arctic, the risk of negative impact on the environment is very significant. In order to prevent possible environmental damage within the AZRF, it is advisable to carry out activities related to the implementation of continuous monitoring of the environment aimed at detecting sources that pose a potential threat to the ecosystem. Taking into account the harsh Arctic climate, the lack of the possibility of year-round land access to industrial facilities located in the Russian Arctic, the scale and peculiarities of the implementation of Arctic offshore projects for the extraction and processing of hydrocarbons, the length and congestion of the used logistic artery - the Northern Sea Route, the choice of means, which are used for monitoring the ecological situation is justified by their mobility and efficiency. In particular, such means include technologies that allow remote monitoring of the environmental situation of industrial facilities. The article outlines the role of remote methods of environmental monitoring and control in the system of environmental protection measures of the Russian Arctic, presents methods for assessing the impact of industrial facilities of the oil and gas complex (OGC) on the environment of the Russian Arctic, presents the results of assessing the effectiveness of using remote methods of environmental monitoring of industrial facilities for the production and processing of hydrocarbons (HC) in the AZRF. The scientific novelty of the study lies in the substantiation of the ecological and economic feasibility of using the methods of remote monitoring of the ecological situation in the Arctic.


2007 ◽  
Vol 7 (3) ◽  
pp. 227-238 ◽  
Author(s):  
S.H. Razavi ◽  
A. Abolmaali ◽  
M. Ghassemieh

AbstractIn the proposed method, the variation of displacement in each time step is assumed to be a fourth order polynomial in time and its five unknown coefficients are calculated based on: two initial conditions from the previous time step; satisfying the equation of motion at both ends of the time step; and the zero weighted residual within the time step. This method is non-dissipative and its dispersion is considerably less than in other popular methods. The stability of the method shows that the critical time step is more than twice of that for the linear acceleration method and its convergence is of fourth order.


2007 ◽  
Vol 46 (9) ◽  
pp. 1480-1497 ◽  
Author(s):  
Olivier P. Prat ◽  
Ana P. Barros

Abstract The focus of this paper is on the numerical solution of the stochastic collection equation–stochastic breakup equation (SCE–SBE) describing the evolution of raindrop spectra in warm rain. The drop size distribution (DSD) is discretized using the fixed-pivot scheme proposed by Kumar and Ramkrishna, and new discrete equations for solving collision breakup are presented. The model is evaluated using established coalescence and breakup parameterizations (kernels) available in the literature, and in that regard this paper provides a substantial review of the relevant science. The challenges posed by the need to achieve stable and accurate numerical solutions of the SCE–SBE are examined in detail. In particular, this paper focuses on the impact of varying the shape of the initial DSD on the equilibrium solution of the SCE–SBE for a wide range of rain rates and breakup kernels. The results show that, although there is no dependence of the equilibrium DSD on initial conditions for the same rain rate and breakup kernel, there is large variation in the time that it takes to reach steady state. This result suggests that, in coupled simulations of in-cloud motions and microphysics and for short time scales (<30 min) for which transient conditions prevail, the equilibrium DSD may not be attainable except for very heavy rainfall. Furthermore, simulations for the same initial conditions show a strong dependence of the dynamic evolution of the DSD on the breakup parameterization. The implication of this result is that, before the debate on the uniqueness of the shape of the equilibrium DSD can be settled, there is critical need for fundamental research including laboratory experiments to improve understanding of collisional mechanisms in DSD evolution.


2020 ◽  
Vol 18 (06) ◽  
pp. 2050029
Author(s):  
Xinli Zhang ◽  
Deshan Sun ◽  
Wei Jiang

This paper analyzes the chaotic dynamics of a quantum Cournot duopoly game with bounded rational players by applying quantum game theory. We investigate the impact of quantum entanglement on the stability of the quantum Nash equilibrium points and chaotic dynamics behaviors of the system. The result shows that the stability region decreases with the quantum entanglement increasing. The adjustment speeds of bounded rational players can lead to chaotic behaviors, and quantum entanglement accelerates the bifurcation and chaos of the system. Numerical simulations demonstrate the chaotic features via stability region, bifurcation, largest Lyapunov exponent, strange attractors, sensitivity to initial conditions and fractal dimensions.


2014 ◽  
Vol 651-653 ◽  
pp. 1168-1172
Author(s):  
Yong Zhong Ren ◽  
Yan Peng Zhu ◽  
Yong Zhou

In the present code, the embedded depth is determined on the multi-pivot support structure to consider the impact of seepage less, and it is verified by anti-seepage stability for single layer aquifer, while the embedded depth is determined not expressly provide for heterogeneity aquifer of the coefficient of permeability difference. However, in the northwest loess areas, the formation is complex, permeability coefficient is variations. To solve this problem, the arctic investigates change law that the impacts of embedded depth variation change on bending moment, the vertical displacement of bottom and maximum flow velocity under seepage, and made a qualitative research model. And the impact of seepage on the embedded depth cannot be ignored and a greater impact on the stability of the pit.


2014 ◽  
Vol 11 (7) ◽  
pp. 11139-11178 ◽  
Author(s):  
B. R. Carter ◽  
J. R. Toggweiler ◽  
R. M. Key ◽  
J. L. Sarmiento

Abstract. We introduce a composite tracer, Alk*, that has a global distribution primarily determined by CaCO3 precipitation and dissolution. Alk* also highlights riverine alkalinity plumes that are due to dissolved calcium carbonate from land. We estimate the Arctic receives approximately twice the riverine alkalinity per unit area as the Atlantic, and 8 times that of the other oceans. Riverine inputs broadly elevate Alk* in the Arctic surface and particularly near river mouths. Strong net carbonate precipitation lowers basin mean Indian and Atlantic Alk*, while upwelling of dissolved CaCO3 rich deep waters elevates Northern Pacific and Southern Ocean Alk*. We use the Alk* distribution to estimate the carbonate saturation variability resulting from CaCO3 cycling and other processes. We show regional variations in surface carbonate saturation are due to temperature changes driving CO2 fluxes and, to a lesser extent, freshwater cycling. Calcium carbonate cycling plays a tertiary role. Monitoring the Alk* distribution would allow us to isolate the impact of acidification on biological calcification and remineralization.


2018 ◽  
Vol 140 (3) ◽  
Author(s):  
Ž. Staliulionis ◽  
H. Conseil-Gudla ◽  
S. Mohanty ◽  
M. Jabbari ◽  
R. Ambat ◽  
...  

Abstract The aim of this paper is to model moisture ingress into a closed electronic enclosure under isothermal and non-isothermal conditions. As a consequence, an in-house code for moisture transport is developed using the Resistor-Capacitor (RC) method, which is efficient as regards computation time and resources. First, an in-house code is developed to model moisture transport through the enclosure walls driven by diffusion, which is based on the Fick's first and second law. Thus, the model couples a lumped analysis of moisture transport into the box interior with a modified one-dimensional (1D) analogy of Fick's second law for diffusion in the walls. Thereafter, under non-isothermal conditions, the moisture RC circuit is coupled with the same configuration of thermal RC circuit. The paper concerns the study of the impact of imperfections in the enclosure for the whole diffusion process. Moreover, a study of the impact of wall thickness, different diffusion coefficient, and initial conditions in the wall for the moisture transport is accomplished. Comparison of modeling and experimental results showed that the RC model is very applicable for simple and rough enclosure design. Furthermore, the experimental and modeling results indicate that the imperfections, with certain limits, do not have a significant effect on the moisture transport. The modeling of moisture transport under non-isothermal conditions shows that the internal moisture oscillations follow ambient temperature changes albeit with a delay. Although, moisture ingress is slightly dependent on ambient moisture oscillations; however, it is not so dominant until equilibrium is reached.


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