Polynya activity in the Arctic Ocean from 1958 to 1997

Winsor, Peter; Björk, Göran

doi:10.1029/1999jc900305

Cited by 141 publications

(200 citation statements)

References 29 publications

(27 reference statements)

Supporting

Mentioning

187

Contrasting

Unclassified

Order By: Relevance

“…5). These values are similar to the amount produced in the Storfjorden polynya (Skogseth et al, 2004) and in Arctic polynyas (Cavalieri and Martin, 1994;Winsor and Björk, 2000). On Central Bank and Great Bank the vol- …”

Section: Cold Deep Watersupporting

confidence: 71%

“…Midttun, 1985;Martin and Cavalieri, 1989;Schauer, 1995;Skogseth et al, 2004). West of Novaya Zemlya cold easterly winds during winter frequently open a polynya (Martin and Cavalieri, 1989) and more than 10 m of ice forms in this polynya during an average winter (Winsor and Björk, 2000). A recurring polynya is also known to form in Storfjorden ( Fig.…”

Section: Introductionmentioning

confidence: 99%

“…According to Harms (1997) the initial stratification is dependent on the Atlantic influence on ice freezing or melting, and Backhaus et al (1997) argued that import of warm Atlantic Water (AW) onto the Barents Sea shelf may cause a negative feedback on both deep reaching convection and ice growth. The latter is important for dense water formation through input of salt (Martin and Cavalieri, 1989;Winsor and Björk, 2000;Schauer, 1995;Skogseth et al, 2004). Furthermore, it has been recognized that as the climate of the region depends greatly on the Atlantic inflow, any variations in the characteristics of this inflow would inevitably have consequences for the production of dense water (Harms, 1997).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Dense water formation and circulation in the Barents Sea

Årthun

Ingvaldsen

Smedsrud

et al. 2011

Deep Sea Research Part I: Oceanographic Research Papers

View full text Add to dashboard Cite

Dense water masses from Arctic shelf seas are an important part of the Arctic thermohaline system. We present previously unpublished observations from shallow banks in the Barents Sea, which reveal large interannual variability in dense water temperature and salinity. To examine the formation and circulation of dense water, and the processes governing interannual variability, a regional coupled ice-ocean model is applied to the Barents

show abstract

Section: Cold Deep Watersupporting

confidence: 71%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Dense water formation and circulation in the Barents Sea

Årthun

Ingvaldsen

Smedsrud

et al. 2011

Deep Sea Research Part I: Oceanographic Research Papers

View full text Add to dashboard Cite

show abstract

“…Polynya flux models have been used to estimate the contribution of polynyas to salt and dense water production in polar oceans (e.g. Winsor & Björk 2000;Krumpen et al 2011). However, although intuitively appealing, the equations underpinning these models have never been derived from first principles.…”

Section: Summary and Concluding Remarksmentioning

confidence: 99%

“…The momentum balance in the new-ice region is assumed to be such that the ice is constrained to move with a velocity close or equal to that of the pack ice, and so U X ≈ U p . Finally, H X is typically either prescribed (Pease 1987;Ou 1988), parameterised as a function of various oceanic and atmospheric variables such as polynya fetch and wind speed (Alam & Curry 1998;Winsor & Björk 2000), or derived from simple hydrodynamic models of the frazil ice-water mixture (Bauer & Martin 1983;Biggs, Morales Maqueda & Willmott 2000).…”

mentioning

confidence: 99%

The opening of wind-driven polynyas

2014

View full text Add to dashboard Cite

The opening of wind-driven coastal polynyas has often been investigated using idealised flux models. Polynya flux models postulate that the boundary separating the region of thin ice adjacent to the coast within the polynya from the thicker ice piling up downstream is a mathematical shock. To conserve mass, any divergence of the ice flux across the shock translates into a change in the shock's position or, in other words, a change in the width of the thin-ice region of the polynya. Polynya flux models are physically incomplete in that, while they conserve ice mass, they do not conserve linear momentum. In this paper, we investigate the improvements that can be achieved in the simulation of polynyas by imposing conservation of momentum as well as mass. We start by adopting a mathematically solid formulation of the ice mass and momentum balances throughout the polynya region, from the coast to the pack ice. Hydrostatic and plastic versions of the ice internal forces are used in the model. Two different approaches are then explored. We first postulate the existence of a shock at the seaward edge of the thin-ice region of the polynya and derive jump conditions for the conservation of ice mass and momentum at the shock which are consistent with the continuous model physics. Polynyas simulated by this mass-and momentum-conserving shock model always reach a steady state if the polynya forcing is uniform in space and constant in time. This is also true for all polynya flux models presented previously in the literature, but the location of the steady-state polynya edge and the time required to reach it can greatly differ between shock formulations and more simplistic flux ones. We next relax the assumption that a shock exists and let the boundary between thin ice and piling up ice emerge naturally as part of the full solution of the continuous model equations. Polynyas simulated in this way are very different from those simulated by either shock or flux models. Most notably, we find that steady-state polynya solutions are not always attainable in the continuous model. We determine under which conditions this is so and explain how such unsteady solutions come about. We also show that, in those cases when a steady-state solution exists in the continuous model, the steady-state polynya width is considerably larger than in the shock model, and the time required to attain it is accordingly longer. The occurrence of such significant differences between the polynya solutions calculated with flux and shock models, on the one hand, and with more sophisticated continuous † Email address for correspondence: mamm@noc.ac.uk

show abstract