A new parameterization of coastal drag to simulate landfast ice in deep marginal seas in the Arctic

2022 ◽  
Author(s):  
Yuqing Liu ◽  
Martin Losch ◽  
Nils Christian Hutter ◽  
Longjiang Mu
Keyword(s):  
The Arctic ◽  
Marginal Seas ◽  
Landfast Ice

scholarly journals Mapping pan-Arctic landfast sea ice stability using Sentinel-1 interferometry

2019 ◽  
Vol 13 (2) ◽  
pp. 557-577 ◽  
Author(s):  
Dyre O. Dammann ◽  
Leif E. B. Eriksson ◽  
Andrew R. Mahoney ◽  
Hajo Eicken ◽  
Franz J. Meyer
Keyword(s):  
Sea Ice ◽  
The Arctic ◽  
Sea Ice Extent ◽  
Marginal Seas ◽  
Nares Strait ◽  
Novel Approach ◽  
Landfast Ice ◽  
Landfast Sea Ice ◽  
Fringe Patterns ◽  
The Stability

Abstract. Arctic landfast sea ice has undergone substantial changes in recent decades, affecting ice stability and including potential impacts on ice travel by coastal populations and on industry ice roads. We present a novel approach for evaluating landfast sea ice stability on a pan-Arctic scale using Synthetic Aperture Radar Interferometry (InSAR). Using Sentinel-1 images from spring 2017, we discriminate between bottomfast, stabilized, and nonstabilized landfast ice over the main marginal seas of the Arctic Ocean (Beaufort, Chukchi, East Siberian, Laptev, and Kara seas). This approach draws on the evaluation of relative changes in interferometric fringe patterns. This first comprehensive assessment of Arctic bottomfast sea ice extent has revealed that most of the bottomfast sea ice is situated around river mouths and coastal shallows. The Laptev and East Siberian seas dominate the aerial extent, covering roughly 4100 and 5100 km2, respectively. These seas also contain the largest extent of stabilized and nonstabilized landfast ice, but are subject to the largest uncertainties surrounding the mapping scheme. Even so, we demonstrate the potential for using InSAR for assessing the stability of landfast ice in several key regions around the Arctic, providing a new understanding of how stability may vary between regions. InSAR-derived stability may serve for strategic planning and tactical decision support for different uses of coastal ice. In a case study of the Nares Strait, we demonstrate that interferograms may reveal early-warning signals for the breakup of stationary sea ice.

scholarly journals Estimating Meltwater Drainage Onset Timing and Duration of Landfast Ice in the Canadian Arctic Archipelago Using AMSR-E Passive Microwave Data

2020 ◽  
Vol 12 (6) ◽  
pp. 1033
Author(s):  
Yasuhiro Tanaka
Keyword(s):  
Time Series ◽  
Large Scale ◽  
Polynomial Regression ◽  
The Arctic ◽  
Imaging Spectrometer ◽  
Earth Observing System ◽  
Medium Resolution ◽  
Onset Timing ◽  
Landfast Ice ◽  
Heat Budgets

Meltwater drainage onset (DO) timing and drainage duration (DD) related to snowmelt-water redistribution are both important for understanding not only the Arctic energy and heat budgets but also the salt/heat balance of the mixed layer in the ocean and sea-ice ecosystem. We present DO and DD as determined from the time series of Advanced Microwave Scanning Radiometer-Earth observing system (AMSR-E) melt pond fraction (MPF) estimates in an area with Canadian landfast ice. To address the lack of evaluation on a day-by-day basis for the AMSR-E MPF estimate, we first compared AMSR-E MPF with the daily Medium Resolution Imaging Spectrometer (MERIS) MPF. The AMSR-E MPF estimate correlates significantly with the MERIS MPF (r = 0.73–0.83). The estimate has a product quality similar to the MERIS MPF only when the albedo is around 0.5–0.7 and a positive bias of up to 10% in areas with an albedo of 0.7–0.9, including melting snow. The DO/DD estimates are determined by using a polynomial regression curve fitted on the time series of the AMSR-E MPF. The DOs/DDs from time series of the AMSR-E and MERIS MPFs are compared, revealing consistency in both DD and DO. The DO timing from 2006 to 2011 is correlated with melt onset timing. To the best of our knowledge, our study provides the first large-scale information on both DO timing and DD.

scholarly journals Snow depth on Arctic sea ice from historical in situ data

2017 ◽  
Author(s):  
Elena V. Shalina ◽  
Stein Sandven
Keyword(s):  
Standard Deviation ◽  
Snow Depth ◽  
Arctic Sea Ice ◽  
North Pole ◽  
The Arctic ◽  
Average Height ◽  
Data Set ◽  
Marginal Seas ◽  
East Siberian Sea ◽  
Level Ice

Abstract. In this paper we analyze snow data from Soviet airborne expeditions Sever that was collected in the Arctic around places of landings in March, April and May and cover much wider area than the region of observations of Soviet North Pole drifting stations. Particularly, there were a lot of Sever observations in the Eurasian seas. We investigate the following snow parameters: average snow depth on the level ice, height and area of sastrugi, depth of snow dunes attached to ice ridges and depth of snow on hummocks. We have built new snow depth climatology for the late winter that was calculated using both Sever expedition and North Pole drifting station observations. Our result refines the description of snow depth in the central Arctic and provides detailed information on snow depth in the marginal seas. In the 1970s–80s the snow cover in the central Arctic had the following characteristics: the snow depth of the undisturbed snow was 21.2 cm, the depth of sastrugi (that occupied about 36 % of the ice surface) was 36.2 cm and the depth of snow assembled near the hummocks and ridges was about 65 cm. For the marginal seas Sever observations revealed that the average depth of undisturbed snow on the level ice changed from 9.8 cm in the Laptev Sea to 15.3 cm in the East Siberian Sea, the topmost value in the East Siberian Sea is explained by the highest proportion of multiyear ice there. Observations demonstrated a very high spatial variability of snow depth in the marginal seas characterized by standard deviation changing from 66 to 100 %. The average height of sastrugi in the Eurasian seas varied from 23 cm to about 32 cm with standard deviation from 50 to 56 %. Average area covered by sastrugi in the marginal seas was estimated as 36.5 % of the area of the ice floe where those features have been observed. The snow map introduced here as a new climatology is built from Sever and North Pole data, with the latter amounted to 6.1 % of the whole data set. On the whole, our snow depth map reveals lower values comparing to Warren climatology in the central Arctic and shows refined information for the Eurasian seas.

scholarly journals Wave dispersion and dissipation in landfast ice: comparison of observations against models

2021 ◽  
Author(s):  
Joey J. Voermans ◽  
Qingxiang Liu ◽  
Aleksey Marchenko ◽  
Jean Rabault ◽  
Kirill Filchuk ◽  
...  
Keyword(s):  
Sea Ice ◽  
Wave Attenuation ◽  
Effective Properties ◽  
Ice Cores ◽  
Wave Dispersion ◽  
The Arctic ◽  
Thin Elastic Plate ◽  
Wave Dissipation ◽  
Short Waves ◽  
Landfast Ice

Abstract. Observations of wave dissipation and dispersion in sea ice are a necessity for the development and validation of wave-ice interaction models. As the composition of the ice layer can be extremely complex, most models treat the ice layer as a continuum with effective, rather than independently measurable, properties. While this provides opportunities to fit the model to observations, it also obscures our understanding of the wave-ice interactive processes, particularly, it hinders our ability to identify under which environmental conditions these processes are of significance. Here, we aimed to reduce the number of free variables available by studying wave dissipation in landfast ice. That is, in continuous sea ice, such as landfast ice, the effective properties of the continuum ice layer should revert to the material properties of the ice. We present observations of wave dispersion and dissipation from a field experiment on landfast ice in the Arctic and Antarctic. Independent laboratory measurements were performed on sea ice cores from a neighbouring fjord in the Arctic to estimate the ice viscosity. Results show that the dispersion of waves in landfast ice is well described by theory of a thin elastic plate and such observations could provide an estimate of the elastic modulus of the ice. Observations of wave dissipation in landfast ice are about an order of magnitude larger than in ice floes and broken ice. Comparison of our observations against models suggests that wave dissipation is attributed to the viscous dissipation within the ice layer for short waves only, whereas turbulence generated through the interactions between the ice and waves is the most likely process for the dissipation of wave energy for long periods. The separation between short and long waves in this context is expected to be determined by the ice thickness through its influence on the lengthening of short waves. Further studies are required to measure turbulence underneath the ice independently of observations of wave attenuation to confirm our interpretation of the results.

scholarly journals Approaching Freshet beneath Landfast Ice in Kugmallit Bay on the Canadian Arctic Shelf: Evidence from Sensor and Ground Truth Data

ARCTIC ◽  
2009 ◽  
Vol 61 (1) ◽  
pp. 76 ◽  
Author(s):  
Tony R. Walker ◽  
Jon Grant ◽  
Peter Jarvis
Keyword(s):  
Arctic Ocean ◽  
Ground Truth ◽  
Open Water ◽  
Early Spring ◽  
The Arctic ◽  
Ground Truth Data ◽  
The North ◽  
Landfast Ice ◽  
North American Arctic ◽  
Mackenzie River

The Mackenzie River is the largest river in the North American Arctic. Its huge freshwater and sediment load impacts the Canadian Beaufort Shelf, transporting large quantities of sediment and associated organic carbon into the Arctic Ocean. The majority of this sediment transport occurs during the freshet peak flow season (May to June). Mackenzie River-Arctic Ocean coupling has been widely studied during open water seasons, but has rarely been investigated in shallow water under landfast ice in Kugmallit Bay with field-based surveys, except for those using remote sensing. We observed and measured sedimentation rates (51 g m-2 d-1) and the concentrations of chlorophyll a (mean 2.2 ?g L-1) and suspended particulate matter (8.5 mg L-1) and determined the sediment characteristics during early spring, before the breakup of landfast ice in Kugmallit Bay. We then compared these results with comparable data collected from the same site the previous summer. Comparison of organic quality in seston and trapped material demonstrated substantial seasonal differences. The subtle changes in biological and oceanographic variables beneath landfast ice that we measured using sensors and field sampling techniques suggest the onset of a spring melt occurring hundreds of kilometres farther south in the Mackenzie Basin.

Sustaining ecological and subsistence functions in conservation areas: eider habitat and access by Native hunters along landfast ice

2018 ◽  
Vol 45 (4) ◽  
pp. 361-369 ◽  
Author(s):  
JAMES R. LOVVORN ◽  
AARIEL R. ROCHA ◽  
ANDREW H. MAHONEY ◽  
STEPHEN C. JEWETT
Keyword(s):  
Chukchi Sea ◽  
Open Water ◽  
The Arctic ◽  
Cash Income ◽  
Migration Route ◽  
Conservation Areas ◽  
Subsistence Hunting ◽  
Industrial Activities ◽  
Landfast Ice ◽  
Ice Edge

SUMMARYIn the Arctic, rapid climate change has kindled efforts to delineate and project the future of important habitats for marine birds and mammals. These animals are vital to subsistence economies and cultures, so including the needs of both animals and hunters in conservation planning is key to sustaining social-ecological systems. In the northeast Chukchi Sea, a nearshore corridor of open water is a major spring migration route for half a million eider ducks that are hunted along the landfast ice. Zoning areas for industrial activities or conservation should consider both eider habitat and hunter access to those habitats from the variable ice edge. Based on benthic sampling in 2010‒2012, a model of eider foraging energetics and satellite data on ice patterns in April and May 1997‒2011, we mapped the range of positions of the landfast ice edge relative to a given dispersion of habitat suitable for eider feeding. In some sectors, feeding areas were too limited or too far from landfast ice to provide regular hunting access. In other sectors, overlap of the ice edge with eider feeding habitat was quite variable, but often within a consistent geographic range. Areas accessible to hunters were a small fraction of total eider habitat, so areas adequate for conserving eiders would not necessarily include areas that meet the hunters’ needs. These results can inform spatial planning of industrial activities that yield cash income critical to subsistence hunting in less developed locations. Our study provides an approach for mapping ‘subsistence conservation areas’ throughout the Arctic and an example for such efforts elsewhere.

scholarly journals Evidence for an increasing role of ocean heat in Arctic winter sea ice growth

2021 ◽  
pp. 1-42
Author(s):  
Robert Ricker ◽  
Frank Kauker ◽  
Axel Schweiger ◽  
Stefan Hendricks ◽  
Jinlun Zhang ◽  
...  
Keyword(s):  
Sea Ice ◽  
Reanalysis Data ◽  
Arctic Sea Ice ◽  
Satellite Observations ◽  
The Arctic ◽  
Ice Growth ◽  
Marginal Seas ◽  
Air Temperatures ◽  
Barents And Kara Seas ◽  
The Impact

AbstractWe investigate how sea ice decline in summer and warmer ocean and surface temperatures in winter affect sea ice growth in the Arctic. Sea ice volume changes are estimated from satellite observations during winter from 2002 to 2019 and partitioned into thermodynamic growth and dynamic volume change. Both components are compared to validated sea ice-ocean models forced by reanalysis data to extend observations back to 1980 and to understand the mechanisms that cause the observed trends and variability. We find that a negative feedback driven by the increasing sea ice retreat in summer yields increasing thermodynamic ice growth during winter in the Arctic marginal seas eastward from the Laptev Sea to the Beaufort Sea. However, in the Barents and Kara Seas, this feedback seems to be overpowered by the impact of increasing oceanic heat flux and air temperatures, resulting in negative trends in thermodynamic ice growth of -2 km3month-1yr-1 on average over 2002-2019 derived from satellite observations.

scholarly journals A probabilistic seabed-ice keel interaction model

2021 ◽  
Author(s):  
Frédéric Dupont ◽  
Dany Dumont ◽  
Jean-François Lemieux ◽  
Elie Dumas-Lefebvre ◽  
Alain Caya
Keyword(s):  
Sea Ice ◽  
Thickness Distribution ◽  
Probabilistic Approach ◽  
Joint Probability ◽  
Interaction Model ◽  
Ocean Model ◽  
The Arctic ◽  
Ice Dynamics ◽  
Landfast Ice ◽  
The Mean

Abstract. In some coastal regions of the Arctic Ocean, as well as in shallow seasonally ice-covered seas, grounded ice ridges contribute to stabilizing and maintaining a landfast ice cover. Recently, a grounding scheme representing this effect on sea ice dynamics was introduced and tested in a coupled ice-ocean model. This grounding scheme, based on a parameterization of ridged keel thickness linearly correlated to the mean thickness, improves the simulation of landfast ice in many regions such as in the East Siberian Sea, the Laptev Sea and along the coast of Alaska. Nevertheless, this parameterization is based solely on the mean properties of sea ice. Here, we extend the parameterization by taking into account subgridscale ice thickness distribution and bathymetry distributions, which are generally non-normal, and by computing the maximum seabed stress as a joint probability interaction between the ice and the seabed. The probabilistic approach shows a reasonably good agreement with observations and with the previously proposed grounding scheme while potentially offering more physical insights in the formation of landfast ice.

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