scholarly journals Nonextensive Dynamics of Drifting Sea Ice

2013 ◽  
Vol 2013 ◽  
pp. 1-6
Author(s):  
Alexandre Chmel ◽  
Victor Smirnov
Keyword(s):  
Arctic Ocean ◽  
Distribution Functions ◽  
Nonequilibrium Dynamics ◽  
The Arctic ◽  
Field Observations ◽  
The Arctic Ocean ◽  
Ice Floes ◽  
Energy Distribution Functions ◽  
Ice Pack

Cycles of ice pack fragmentation in the Arctic Ocean are caused by the irregular drift dynamics. In February 2004, the Russian ice-research camp North Pole 32 established on a floe in the Arctic Ocean ceased its working activity and was abandoned after a catastrophic icequake. In this communication, the data collected during the last month of the field observations were used for calculating the changes in the kinetic energy of the ice floe. The energy distribution functions corresponding to periods of different drift intensity were analyzed using the Tsallis statistics, which allow one to assess a degree of deviation of an open dynamic system, such as the drifting ice, from its equilibrium state. The obtained results evidenced that the above-mentioned critical fragmentation has occurred in the period of substantially nonequilibrium dynamics of the system of ice floes. The determination of the state of the pack (in the sense of its equilibrium/nonequilibrium) could provide some useful information on forthcoming icequakes.

The Navigation of Arctic Polar Submarines

1984 ◽  
Vol 37 (2) ◽  
pp. 155-179 ◽  
Author(s):  
Waldo K. Lyon
Keyword(s):  
Arctic Ocean ◽  
The Arctic ◽  
The North ◽  
Sonar System ◽  
The Us ◽  
Us Navy ◽  
The Arctic Ocean ◽  
The Many ◽  
Ice Pack

In September 1931 Sir Hubert Wilkins and Harald Sverdrup made the first attempt to explore the Arctic Ocean by submarine in Wilkins's Nautilus. The Nautilus was the ex-Navy submarine O-12 modified with topside runners to slide against the underside of the sea ice. Seventeen years later the US Navy developed the sonar system necessary for safely piloting a diesel-battery submarine underneath the ice pack and began exploration of ice covered areas.In 1957, with the nuclear-powered Nautilus, the US Navy began exploration far into the Arctic Ocean. Problems were found concerning determination of ship's position, ice avoidance manoeuvres, and surfacing up through ice. Sonar and inertial navigation equipments and operating techniques were developed to solve these problems. Submarines have since sailed to all parts of the Arctic Ocean during all seasons — more than twenty explorations since 1957. The history, problems and interrelationships of the many explorations are described.Dr Lyon's paper was presented at a colloquium on the conquest of the North Pole held in Paris, 7–1 1 November 1983, and organized by the Centre d'Etudes Arctiques by whose permission it is here published. (Throughout the paper miles means nautical miles.)

Reflections on Arctic Maritime Delimitations: A Comparative Analysis between the Case Law and State Practice

2011 ◽  
Vol 80 (4) ◽  
pp. 459-484
Author(s):  
Yoshifumi Tanaka
Keyword(s):  
Comparative Analysis ◽  
Arctic Ocean ◽  
Case Law ◽  
The Arctic ◽  
Coastal State ◽  
Ocean Governance ◽  
State Practice ◽  
The Arctic Ocean

AbstractThe determination of spatial ambit of the coastal State jurisdiction is fundamental for ocean governance and the same applies to the Arctic Ocean. In this regard, a question arises how it is possible to delimit marine spaces where the jurisdiction of two or more coastal States overlaps. Without rules on maritime delimitation in marine spaces where the jurisdiction of coastal States overlaps, the legal uses of these spaces cannot be enjoyed effectively. In this sense, maritime delimitation is of paramount importance in the Arctic Ocean governance. Thus, this study will examine Arctic maritime delimitations by comparing them to the case law concerning maritime delimitation. In so doing, this study seeks to clarify features of Arctic maritime delimitations.

Coupled Sea Ice-Ocean Model of the Arctic Ocean

1998 ◽  
Vol 120 (2) ◽  
pp. 77-84 ◽  
Author(s):  
I. V. Polyakov ◽  
I. Yu. Kulakov ◽  
S. A. Kolesov ◽  
N. Eu. Dmitriev ◽  
R. S. Pritchard ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
Three Dimensional ◽  
Coupled Model ◽  
Ocean Model ◽  
Distribution Functions ◽  
Constitutive Law ◽  
Prognostic Models ◽  
The Arctic ◽  
The Arctic Ocean ◽  
Ocean Layer

A fully prognostic coupled ice-ocean model is described. The ice model is based on the elastic-plastic constitutive law with ice mass and compactness described by distribution functions. The ice thermodynamics model is applied individually to each ice thickness category. Advection of the ice partial mass and concentrations is parameterized by a fourth-order algorithm that conserves monotonicity of the solution. The ocean is described as a three-dimensional time-dependent baroclinic model with free surface. The coupled model is applied to establish the Arctic Ocean seasonal climatology using fully prognostic models for ice and ocean. Results reflect the importance of the ice melting/freezing in the formation of the thermohaline structure of the upper ocean layer.

scholarly journals A 50 % increase in the mass of terrestrial particles delivered by the Mackenzie River into the Beaufort Sea (Canadian Arctic Ocean) over the last 10 years

2015 ◽  
Vol 12 (11) ◽  
pp. 3551-3565 ◽  
Author(s):  
D. Doxaran ◽  
E. Devred ◽  
M. Babin
Keyword(s):  
Organic Carbon ◽  
Arctic Ocean ◽  
Suspended Solids ◽  
Beaufort Sea ◽  
Freshwater Discharge ◽  
The Arctic ◽  
Field Observations ◽  
The Arctic Ocean ◽  
Arctic Rivers ◽  
Mackenzie River

Abstract. Global warming has a significant impact on the regional scale on the Arctic Ocean and surrounding coastal zones (i.e., Alaska, Canada, Greenland, Norway and Russia). The recent increase in air temperature has resulted in increased precipitation along the drainage basins of Arctic rivers. It has also directly impacted land and seawater temperatures with the consequence of melting permafrost and sea ice. An increase in freshwater discharge by main Arctic rivers has been clearly identified in time series of field observations. The freshwater discharge of the Mackenzie River has increased by 25% since 2003. This may have increased the mobilization and transport of various dissolved and particulate substances, including organic carbon, as well as their export to the ocean. The release from land to the ocean of such organic material, which has been sequestered in a frozen state since the Last Glacial Maximum, may significantly impact the Arctic Ocean carbon cycle as well as marine ecosystems. In this study we use 11 years of ocean color satellite data and field observations collected in 2009 to estimate the mass of terrestrial suspended solids and particulate organic carbon delivered by the Mackenzie River into the Beaufort Sea (Arctic Ocean). Our results show that during the summer period, the concentration of suspended solids at the river mouth, in the delta zone and in the river plume has increased by 46, 71 and 33%, respectively, since 2003. Combined with the variations observed in the freshwater discharge, this corresponds to a more than 50% increase in the particulate (terrestrial suspended particles and organic carbon) export from the Mackenzie River into the Beaufort Sea.

Recent behavior of the Nares Strait ice arches: anomalous collapses and enhanced export of multi-year ice from the Arctic Ocean

2020 ◽  
Author(s):  
Kent Moore ◽  
Stephen Howell ◽  
Mike Brady ◽  
Xiaoyong Xu ◽  
Kaitlin McNeil
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
The Arctic ◽  
Nares Strait ◽  
Short Period ◽  
The Arctic Ocean ◽  
Arctic Ice ◽  
Policy Communities ◽  
Ice Pack ◽  
Area And Volume

<p>The ice arches that usually develop at the northern and southern ends of Nares Strait play an important role in modulating the export of multi-year sea ice out of the Arctic Ocean.   As a result of global warming, the Arctic Ocean is evolving towards an ice pack that is younger, thinner and more mobile and the fate of its multi-year ice is becoming of increasing interest to both the scientific and policy communities.  Here, we use sea ice motion retrievals derived from Sentinel-1 imagery to report on recent behaviour of these ice arches and the associated ice flux. In addition to the previously identified early collapse of the northern ice arch in May 2017, we report that this arch failed to develop during the winters of 2018 and 2019.  In contrast, we report that the southern ice arch was only present for a short period of time during the winter of 2018.  We also show that the duration of arch formation has decreased over the past 20 years as ice in the region has thinned, while the ice area and volume fluxes have both increased.  These results suggest that a transition is underway towards a state where the formation of these arches will become atypical with a concomitant increase in the export of multi-year ice accelerating the transition towards a younger and thinner Arctic ice pack.</p>

Dissolved Neodymium Isotopes Trace Origin and Spatiotemporal Evolution of Modern Arctic Sea Ice

2020 ◽  
Author(s):  
Georgi Laukert ◽  
Dorothea Bauch ◽  
Ilka Peeken ◽  
Thomas Krumpen ◽  
Kirstin Werner ◽  
...  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Surface Waters ◽  
Ice Cores ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Spatiotemporal Evolution ◽  
Arctic Sea ◽  
The Arctic Ocean ◽  
Ice Floes

<p>The lifetime and thickness of Arctic sea ice have markedly decreased in the recent past. This affects Arctic marine ecosystems and the biological pump, given that sea ice acts as platform and transport medium of marine and atmospheric nutrients. At the same time sea ice reduces light penetration to the Arctic Ocean and restricts ocean/atmosphere exchange. In order to understand the ongoing changes and their implications, reconstructions of source regions and drift trajectories of Arctic sea ice are imperative. Automated ice tracking approaches based on satellite-derived sea-ice motion products (e.g. ICETrack) currently perform well in dense ice fields, but provide limited information at the ice edge or in poorly ice-covered areas. Radiogenic neodymium (Nd) isotopes (ε<sub>Nd</sub>) have the potential to serve as a chemical tracer of sea-ice provenance and thus may provide information beyond what can be expected from satellite-based assessments. This potential results from pronounced ε<sub>Nd</sub> differences between the distinct marine and riverine sources, which feed the surface waters of the different sea-ice formation regions. We present the first dissolved (< 0.45 µm) Nd isotope and concentration data obtained from optically clean Arctic first- and multi-year sea ice (ice cores) collected from different ice floes across the Fram Strait during the RV POLARSTERN cruise PS85 in 2014. Our data confirm the preservation of the seawater ε<sub>Nd</sub>signatures in sea ice despite low Nd concentrations (on average ~ 6 pmol/kg) resulting from efficient brine rejection. The large range in ε<sub>Nd</sub> signatures (~ -10 to -30) mirrors that of surface waters in various parts of the Arctic Ocean, indicating that differences between ice floes but also between various sections in an individual ice core reflect the origin and evolution of the sea ice over time. Most ice cores have ε<sub>Nd</sub> signatures of around -10, suggesting that the sea ice was formed in well-mixed waters in the central Arctic Ocean and transported directly to the Fram Strait via the Transpolar Drift. Some ice cores, however, also revealed highly unradiogenic signatures (ε<sub>Nd</sub> < ~ -15) in their youngest (bottom) sections, which we attribute to incorporation of meltwater from Greenland into newly grown sea ice layers. Our new approach facilitates the reconstruction of the origin and spatiotemporal evolution of isolated sea-ice floes in the future Arctic.</p>

Algal bloom in a melt pond on Canada Basin pack ice

Polar Record ◽  
2015 ◽  
Vol 52 (1) ◽  
pp. 114-117 ◽  
Author(s):  
Ling Lin ◽  
Jianfeng He ◽  
Fang Zhang ◽  
Shunan Cao ◽  
Can Zhang
Keyword(s):  
Arctic Ocean ◽  
Algal Bloom ◽  
Canada Basin ◽  
The Arctic ◽  
Arctic Warming ◽  
Melt Pond ◽  
Melt Ponds ◽  
Pack Ice ◽  
The Arctic Ocean ◽  
Ice Floes

ABSTRACTMelt ponds are common on the surface of ice floes in the Arctic Ocean during spring and summer. Few studies on melt pond algae communities have been accomplished. These studies have shown that these melt ponds were ultra-oligotrophic, and contribute little to overall productivity. However, during the 6th Chinese Arctic Cruise in the Arctic Ocean in summer 2014, a closed coloured melt pond with a chlorophyll a concentration of 15.32 μg/L was observed on Arctic pack ice in the Canada Basin. The bloom was caused by the chlorophyte Carteria lunzensis at an abundance of 15.49×106 cells/L and biomass of 5.07 mg C/L. Primary production within surface melt ponds may need more attention along with Arctic warming.

A Thermodynamic Study of Arctic Paleoclimatology

1971 ◽  
Vol 1 (2) ◽  
pp. 175-187 ◽  
Author(s):  
David M. Shaw ◽  
William L. Donn
Keyword(s):  
Arctic Ocean ◽  
Northern Hemisphere ◽  
Thermodynamic Model ◽  
Ice Cover ◽  
Thermodynamic Study ◽  
The Arctic ◽  
Critical Parameters ◽  
Freezing Level ◽  
The Arctic Ocean

The thermodynamic model of J. Adem has been applied to the determination of Arctic and hemispheric surface temperatures with both ice-covered and ice-free states of the Arctic Ocean. The effect of glaciated and nonglaciated continents is included in the investigation. With an ice cover over the Arctic, as at present, computed temperatures for the polar sea and the Northern Hemisphere correspond closely with present observations. Over a broad range of the critical parameters, removal of the ice cover yields computed temperatures that remain well above freezing level throughout the year. With glaciated continents computed Arctic temperatures are depressed.

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