Numerical Models of Sea Ice - Ocean Interaction in the Marginal Ice Zone PDF Download

Author: Michael Steele
Publisher:
ISBN:
Category :
Languages : en
Pages : 203

View

Book Description

Author: Miles McPhee
Publisher: Springer Science & Business Media
ISBN: 0387783350
Category : Science
Languages : en
Pages : 218

View

Book Description
At a time when the polar regions are undergoing rapid and unprecedented change, understanding exchanges of momentum, heat and salt at the ice-ocean interface is critical for realistically predicting the future state of sea ice. By offering a measurement platform largely unaffected by surface waves, drifting sea ice provides a unique laboratory for studying aspects of geophysical boundary layer flows that are extremely difficult to measure elsewhere. This book draws on both extensive observations and theoretical principles to develop a concise description of the impact of stress, rotation, and buoyancy on the turbulence scales that control exchanges between the atmosphere and underlying ocean when sea ice is present. Several interesting and unique observational data sets are used to illustrate different aspects of ice-ocean interaction ranging from the impact of salt on melting in the Greenland Sea marginal ice zone, to how nonlinearities in the equation of state for seawater affect mixing in the Weddell Sea. The book’s content, developed from a series of lectures, may be appropriate additional material for upper-level undergraduates and first-year graduate students studying the geophysics of sea ice and planetary boundary layers.

Author: W. D. Hibler (III.)
Publisher:
ISBN:
Category :
Languages : en
Pages : 104

View

Book Description
The main goal of the marginal ice zone experiment (MIZEX) is to understand the processes that dictate the advance and retreat of the ice margin. Mechanistic model sensitivity studies can greatly aid in this goal by identifying the relative importance of different processes in the total system. In addition, more complete simulation models can be used both to test the adequacy of current understanding of the marginal ice zone and to serve as an integrating device for complex data sets. This volume contains the main results from a MIZEX modeling workshop held 18-20 October in Hanover, New Hampshire. Modelers interested in both Arctic and Antarctic sea ice were present. The purpose of the workshop was to determine the status of marginal ice zone modeling and to discuss different views on modeling processes in the MIZ. Results from full simulation models, mechanistic models, and empirical statistical models were presented and discussed. In addition, recommendations relevant to experimental measurements were made. The recommendations were divided into ocean, ice, and atmospheric categories; these were also the three main subject areas covered by the presentations. Overall, the workshop helped to identify areas where further simulations are needed to test our understanding and where knowledge of certain processes is lacking.

Author: Jean-Pierre Auclair
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

View

Book Description
The Marginal Ice Zone (MIZ) is a highly dynamic region between the open ocean and the inner ice pack. The ice over this region is subjected to waves, introducing new forces but also changing the ice from a cohesive material to a mobile collection of floes. Until recently, the challenges posed by in-situ ice measurements in the MIZ prevented a detailed characterization of changes in the ice cover. The rapidly changing conditions over short distances have also prevented detailed numerical simulations. Recent developments in observational and computational capabilities allow further investigations of the physical processes for ice formation and wave-ice interactions in the MIZ. Many features of the MIZ remain to be explained and quantified, particularly rapid ice movement near the ice edge and ice thickening under wave pressure. In order to investigate these and support future field and numerical studies, a model of the MIZ is developed with a new numerical method better suited for high resolution. Simulations of waves causing ice compaction and the ice edge jet are then performed to detail the expected impacts of waves on sea ice. The potential of numerical improvements in sea ice models to obtain greater efficiency and accuracy at high resolutions is successfully demonstrated. The addition of the wave radiative stress allows the generation of realistic thickness profiles, provided that the sea ice strength is modified to represent the difference between pack ice and thinner ice. With the same modifications, obliquely incident waves on the ice edge produced an ice edge jet with a range of characteristics depending on wave parameters and modeled interactions. The magnitude of wave attenuation in sea ice and the ice strength are found to be very important factors in the simulations. Consideration of wave effects on ice thickness and drift speed are also shown to have potential to increase both open water and ice formation.

Author: Sirpa Häkkinen
Publisher:
ISBN:
Category : Ocean-atmosphere interaction
Languages : en
Pages : 124

View

Book Description
This study is aimed at the modelling of mesoscale processes such as up/downwelling and ice edge eddies in the marginal ice zones. A 2-dimensional coupled ice-ocean model is used for the study. The ice model is coupled to the reduced gravity ocean model (f-plane) through interfacial stresses. The constitutive equations of the sea ice are formulated on the basis of the Reiner-Rivlin theory. The internal ice stresses are important only at high ice concentrations (90-100%), otherwise the ice motion is essentially free drift, where the air-ice stress is balanced by the ice-water stress. The model was tested by studying the upwelling dynamics. Winds parallel to the ice edge with the ice on the right produce upwelling because the air-ice momentum flux is much greater than air-ocean momentum flux, and thus the Ekman transport is bigger under the ice than in the open water. The upwelling simulation was extended to include temporally varying forcing, which was chosen to vary sinusoidally with 4 day period. This forcing resembles successive cyclone passings. In the model with thin oceanic upper layer, ice bands were formed. The up/downwelling signals do not disappear in wind reversals because of nonlinear advection. This leads to convergences and divergences in oceanic and ice velocities which manifest themselves as ice banding. At least one wind reversal is needed to produce one ice band.

Author: Torge Martin
Publisher:
ISBN:
Category : Sea ice
Languages : de
Pages : 254

View

Book Description

Author: Marie N. Houssais
Publisher:
ISBN:
Category :
Languages : en
Pages : 74

View

Book Description
This report describes a numerical model designed to study the seasonal dynamics of ice-ocean interactions in the Greenland Sea. First the thermodynamic aspect of the problem is examined by means of a coupled thermodynamic sea ice-ocean mixed layer model. Secondly, the ocean dynamics is introduced by embedding the vertical zonal oceanic slab across the Greenland Sea. Sea ice and the under-lying ocean are dynamically interactive in this complete version of the coupled model. Results obtained in these two parts of the study are then outlined and, where possible, compared with some climatological data sets. A special attention is paid to the mixed layer deepening/retreat process, in relation with the seasonal evolution of the ice distribution, as an indicator of the deep convection efficiency in a region where winter deep water formation is expected to occur.

Author: David S. Dimitriou
Publisher:
ISBN: 9781423559023
Category :
Languages : en
Pages : 72

View

Book Description
Numerical models have proven integral to the study of climate dynamics. Sea ice models are critical to the improvement of general circulation models used to study the global climate. The object of this study is to evaluate a high resolution ice-ocean coupled model by comparing it to derived measurements from SMMR and SSM/I satellite observations. Utilized for this study was the NASA Goddard Space Flight (GSFC) Sea Ice Concentration Data Set from the National Snow and Ice Data Center. Using animations of side-by-side presentations, variability comparisons and anomaly values the of similarities and differences between the model and the satellite were noted. The model shows a true representation of the seasonal cycle of ice concentration variation, with natural growth, advection, decay. Model performance is weakest in the East Siberian and Laptev Seas where excessive ice is developed. A 30 day lag in the freezing and melting of ice in Hudson Bay was noted in the model. The use of monthly mean Levitus temperatures adversely affects model performance evidenced by a tendency to grow and retain excess ice in the marginal seas of the Arctic Ocean.

Author: Matti Leppäranta
Publisher: Springer Science & Business Media
ISBN: 3642046835
Category : Science
Languages : en
Pages : 370

View

Book Description
The Second Edition of The Drift of Sea Ice presents the fundamental laws of sea ice drift which come from the material properties of sea ice and the basic laws of mechanics. The resulting system of equations is analysed for the general properties of sea ice drift, the free drift model and analytical models for ice drift in the presence of internal friction, and the construction of numerical ice drift models is detailed. This second edition of a much lauded work, unique on this topic in the English language, has been revised, updated and expanded with much new information and outlines recent results, in particular in relation to the climate problem, mathematical modelling and ice engineering applications. The current book presents the theory, observations, mathematical modelling techniques, and applications of sea ice drift science. The theory is presented from the beginning on a graduate student level, so that students and researchers coming from other fields such as physical oceanography, meteorology, physics, engineering, environmental sciences or geography can use the book as a source book or self-study material. First the drift ice material is presented ending with the concept of ‘ice state’ – the relevant properties in sea ice dynamics. Ice kinematics observations are widely presented with the mathematical analysis methods, and thereafter come drift ice rheology – to close the triangle material – kinematics – stress. The momentum equation of sea ice is derived in detail and its general properties are carefully analysed. Then follow two chapters on analytical models: free drift and drift in the presence of internal friction: These are very important tools in understanding the dynamical behaviour of sea ice. The last topical chapter is numerical models, which are the modern tool to solve ice dynamics problem in short term and long term problems. The closing chapter summarises sea ice dynamics applications and the need of sea ice dynamic knowledge and gives some final remarks on the future of this branch of science.

Author: Miles McPhee
Publisher: Springer
ISBN: 9780387783345
Category : Science
Languages : en
Pages : 0

View

Book Description
At a time when the polar regions are undergoing rapid and unprecedented change, understanding exchanges of momentum, heat and salt at the ice-ocean interface is critical for realistically predicting the future state of sea ice. By offering a measurement platform largely unaffected by surface waves, drifting sea ice provides a unique laboratory for studying aspects of geophysical boundary layer flows that are extremely difficult to measure elsewhere. This book draws on both extensive observations and theoretical principles to develop a concise description of the impact of stress, rotation, and buoyancy on the turbulence scales that control exchanges between the atmosphere and underlying ocean when sea ice is present. Several interesting and unique observational data sets are used to illustrate different aspects of ice-ocean interaction ranging from the impact of salt on melting in the Greenland Sea marginal ice zone, to how nonlinearities in the equation of state for seawater affect mixing in the Weddell Sea. The book’s content, developed from a series of lectures, may be appropriate additional material for upper-level undergraduates and first-year graduate students studying the geophysics of sea ice and planetary boundary layers.