Scattering and reflection of acoustic waves by striated surfaces depicting the Arctic Ocean ice cover

Abstract The research on the ice cover of waterways, rivers, lakes, seas and oceans by satellite remote sensing methods began at the end of the twentieth century. There was a lot of data sources in diverse file formats. It has not yet carried out a comparative assessment of their usefulness. A synthetic indicator of the quality of data sources binding maps resolution, file publication, time delay and the functionality for the user was developed in the research process. It reflects well a usefulness of maps and allows to compare them. Qualitative differences of map content have relatively little impact on the overall assessment of the data sources. Resolution of map is generally acceptable. Actuality has the greatest impact on the map content quality for the current vessel’s voyage planning in ice. The highest quality of all studied sources have the regional maps in GIF format issued by the NWS / NOAA, general maps of the Arctic Ocean in NetCDF format issued by the OSI SAF and the general maps of the Arctic Ocean in GRIB-2 format issued by the NCEP / NOAA. Among them are maps containing information on the quality of presented parameter. The leader among the map containing all three of the basic characteristics of ice cover (ice concentration, ice thickness and ice floe size) are vector maps in GML format. They are the new standard of electronic vector maps for the navigation of ships in ice. Publishing of ice cover maps in the standard electronic map format S-411 for navigation of vessels in ice adopted by the International Hydrographic Organization is advisable in case is planned to launch commercial navigation on the lagoons, rivers and canals. The wide availability of and exchange of information on the state of ice cover on rivers, lakes, estuaries and bays, which are used exclusively for water sports, ice sports and ice fishing is possible using handheld mobile phones, smartphones and tablets.

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Stability of the Arctic Ocean Ice-Cover and Pleistocene Warming Events: Outlining the Problem

Geological History of the Polar Oceans: Arctic versus Antarctic ◽

10.1007/978-94-009-2029-3_15 ◽

1990 ◽

pp. 273-287 ◽

Cited By ~ 1

Author(s):

D. L. Clark

Keyword(s):

Arctic Ocean ◽

Ice Cover ◽

The Arctic ◽

The Arctic Ocean

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Impact of Variable Atmospheric and Oceanic Form Drag on Simulations of Arctic Sea Ice*

Journal of Physical Oceanography ◽

10.1175/jpo-d-13-0215.1 ◽

2014 ◽

Vol 44 (5) ◽

pp. 1329-1353 ◽

Cited By ~ 89

Author(s):

Michel Tsamados ◽

Daniel L. Feltham ◽

David Schroeder ◽

Daniela Flocco ◽

Sinead L. Farrell ◽

...

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Ice Cover ◽

Arctic Sea Ice ◽

The Arctic ◽

Form Drag ◽

Drag Coefficients ◽

Arctic Sea ◽

The Arctic Ocean ◽

Range Of Values

Abstract Over Arctic sea ice, pressure ridges and floe and melt pond edges all introduce discrete obstructions to the flow of air or water past the ice and are a source of form drag. In current climate models form drag is only accounted for by tuning the air–ice and ice–ocean drag coefficients, that is, by effectively altering the roughness length in a surface drag parameterization. The existing approach of the skin drag parameter tuning is poorly constrained by observations and fails to describe correctly the physics associated with the air–ice and ocean–ice drag. Here, the authors combine recent theoretical developments to deduce the total neutral form drag coefficients from properties of the ice cover such as ice concentration, vertical extent and area of the ridges, freeboard and floe draft, and the size of floes and melt ponds. The drag coefficients are incorporated into the Los Alamos Sea Ice Model (CICE) and show the influence of the new drag parameterization on the motion and state of the ice cover, with the most noticeable being a depletion of sea ice over the west boundary of the Arctic Ocean and over the Beaufort Sea. The new parameterization allows the drag coefficients to be coupled to the sea ice state and therefore to evolve spatially and temporally. It is found that the range of values predicted for the drag coefficients agree with the range of values measured in several regions of the Arctic. Finally, the implications of the new form drag formulation for the spinup or spindown of the Arctic Ocean are discussed.

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Fracture of the ice cover on the Arctic Ocean

Creep and Fracture of Ice ◽

10.1017/cbo9780511581397.016 ◽

2010 ◽

pp. 361-390

Author(s):

Erland M. Schulson ◽

Paul Duval

Keyword(s):

Arctic Ocean ◽

Ice Cover ◽

The Arctic ◽

The Arctic Ocean

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Arctic sea-ice area and volume production:1996/97 versus 1997/98

Annals of Glaciology ◽

10.3189/172756402781817527 ◽

2002 ◽

Vol 34 ◽

pp. 447-453 ◽

Cited By ~ 10

Author(s):

Ron Kwok

Keyword(s):

Arctic Ocean ◽

Large Scale ◽

Heat Budget ◽

Ice Cover ◽

Arctic Sea Ice ◽

The Arctic ◽

Ice Thickness ◽

The Arctic Ocean ◽

Volume Production ◽

Area And Volume

AbstractThe RADARSAT geophysical processor system (RGPS) produces measurements of ice motion and estimates of ice thickness using repeat synthetic aperture radar maps of the Arctic Ocean. From the RGPS products, we compute the net deformation and advection of the winter ice cover using the motion observations, and the seasonal ice area and volume production using the estimates of ice thickness. The results from the winters of 1996/97 and 1997/98 are compared. The second winter is of particular interest because it coincides with the Surface Heat Budget of the Arctic Ocean (SHEBA) field program. The character of the deformation of the ice cover from the two years is very different. Over a domain covering a large part of the western Arctic Ocean (~2.5 × 106 km2), the net divergence of that area during the 6 months of the first winter was 2.7% and for the second winter was 49.3%. In a subregion where the SHEBA camp was located, the net divergence was almost 38% compared to a net divergence of the same subregion of ~9% in 1996/97. The resulting deformation created a much larger volume of seasonal ice than in the earlier year. The net seasonal ice-volume production is 1.6 times (0.38 m vs 0.62 m) that of the first year. In addition to the larger divergence, this part of the ice cover advected a longer distance toward the Chukchi Sea over the same time-span. The total coverage of multi-year ice remained almost identical at ~2.08 × 106 km2, or 83% of the initial area of the domain. In this paper, we compare the behavior of the ice cover over the two winters and discuss these observations in the context of large-scale ice motion and atmospheric-pressure pattern.

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Growth of Wave Height with Retreating Ice Cover in the Arctic

10.5194/egusphere-egu2020-6557 ◽

2020 ◽

Author(s):

Changlong Guan ◽

Jingkai Li

Keyword(s):

Arctic Ocean ◽

Surface Waves ◽

Wave Height ◽

Open Water ◽

Ice Cover ◽

Wave Climate ◽

Least Square ◽

The Arctic ◽

The Arctic Ocean ◽

Wave Heights

For the Arctic surface waves, one of the most uncontroversial viewpoints is that their escalation in the past few years is mainly caused by the ice extent reduction. Ice retreat enlarges the open water area, i.e., the effective fetch, and thus allows more wind input energy and available distance for wave evolution. This knowledge has been supported by a few previous studies on the Arctic waves which analyzed the correlation between time-series variations in wave height and ice coverage. However, from the perspective of space, the detailed relationship between retreating ice cover and increasing surface waves is not well studied. Hence, we performed such a study for the whole Arctic and its subregions, which will be helpful for a better understanding of the wave climate and for forecasting waves in the Arctic Ocean.Wave data are produced by twelve-year (2007-2018) hindcasts of summer melt seasons (May-Sept.) and numerical tests with WAVEWATCH III. When a viscoelastic wave-ice model and a spherical multiple-cell grid are applied, simulated wave heights agree with available buoy data and previous research. After the validations, simulated significant wave heights over twelve-year summer melt seasons are used to demonstrate the detailed relationship between the escalation of wave height and reduction of ice extent for the whole Arctic and seven subregions. Through least square regression, we find that the mean wave height in the Arctic Ocean will increase by 0.071m (106km2)-1 when the ice extent is smaller than 9.4&#215;106km2, and roughly 51% is contributed by the enlarged fetch. By analyzing the nondimensional wave energy and comparing the simulated wave height with Wilson IV, we prove the swell is widespread during the summertime in the current Arctic Ocean. Furthermore, we also display the variations in probabilities of occurrence of large waves as ice-edge retreats in seven subregions. Assuming that an ice free period occurs in the Arctic in September, the model results show that the simulated mean wave height is approximately 1.6m and the large waves occur much more frequently, which mean that the growth rate of wave height will be higher if the minimum ice extent keeps reducing in the future.

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Laboratory experiments on Internal Solitary Waves in ice covered waters

10.5194/egusphere-egu21-14991 ◽

2021 ◽

Author(s):

Magda Carr ◽

Peter Sutherland ◽

Andrea Haase ◽

Karl-Ulrich Evers ◽

Ilker Fer ◽

...

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Solitary Waves ◽

Ice Cover ◽

The Arctic ◽

Internal Solitary Waves ◽

Small Scale ◽

Lower Bounding ◽

The Arctic Ocean ◽

Wave Induced

Oceanic internal waves (IWs) propagate along density interfaces and are ubiquitous in stratified water. Their properties are influenced strongly by the nature and form of the upper and lower bounding surfaces of the containing basin(s) in which they propagate.&#160; As the Arctic Ocean evolves to a seasonally more ice-free state, the IW field will be affected by the change. The relationship between IW dynamics and ice is important in understanding (i) the general circulation and thermodynamics in the Arctic Ocean and (ii) local mixing processes that supply heat and nutrients from depth into upper layers, especially the photic zone. This, in turn, has important ramifications for sea ice formation processes and the state of local and regional ecosystems.&#160; Despite this, the effect of diminishing sea ice cover on the IW field (and vice versa) is not well established. A better understanding of IW dynamics in the Arctic Ocean and, in particular, how the IW field is affected by changes in both ice cover and stratification, is central in understanding how the rapidly changing Arctic will adapt to climate change.&#160;An experimental study of internal solitary waves (ISWs) propagating in a stably stratified two-layer fluid in which the upper boundary condition changes from open water to ice are studied for grease, level, and nilas ice. The experiments show that the internal wave-induced flow at the surface is capable of transporting sea-ice in the horizontal direction. In the level ice case, the transport speed of, relatively long ice floes, nondimensionalized by the wave speed is linearly dependent on the length of the ice floe nondimensionalized by the wave length. It will also be shown that bottom roughness associated with different ice types can cause varying degrees of vorticity and small-scale turbulence in the wave-induced boundary layer beneath the ice. Measures of turbulent kinetic energy dissipation under the ice are shown to be comparable to those at the wave density interface. Moreover, in cases where the ice floe protrudes into the pycnocline, interaction with the ice edge can cause the ISW to break or even be destroyed by the process. The results suggest that interaction between ISWs and sea ice may be an important mechanism for dissipation of ISW energy in the Arctic Ocean.&#160;AcknowledgementsThis work was funded through the EU Horizon 2020 Research and Innovation Programme Hydralab+.

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