Sea Ice and Heat Budget

Since the Apr 1957 occupation of the first long-term US drifting station on sea ice, much has been learned about the properties of sea ice as a material. Properties of large, composite sheets of natural sea ice are still to be defined, however, because of the need for accurate knowledge of strength, roughness and albedo, among other parameters. In explanation of the ice cover, studies have been made of energy fluxes, radiative fluxes, albedos, wind and water flow profiles in boundary layers, air and ice temperature profiles and evaporation of condensation. There remain unresolved and complex questions concerning the circumstances under which the present ice cover could change

No Business like Snow Business? The Performance, Coherence, and Dimensions of Organizational Scripts in Organizing Winter Tourism with or without Snow

This study introduces an alternative way of looking at the relation ontology of organizing with the natural environment in the particular context of snow in winter tourism. Adopting the conceptual framework of organizational scripts and assessing their performance, coherence and dimensions, we explore stereotyped programs of actions in the relations between human and non-human actors and their constitutive consequences for organizing sustainable futures with the natural environment. In this context, we identified relations of snow in winter tourism with (1) snow as a manageable resource for the economic viability of winter tourism, (2) snow as a disruptive (disorganizing) resource in the face of climate change and decreasing snow reliability and (3) snow as an artificial resource in the face of technical solutions to uphold economic viability of winter tourism. The analysis contributes to the relational understanding of organizing human and non-human relations through the materialization in organizational scripts

A continuum model of melt pond evolution on Arctic sea ice

[1] During the Northern Hemisphere summer, absorbed solar radiation melts snow and the upper surface of Arctic sea ice to generate meltwater that accumulates in ponds. The melt ponds reduce the albedo of the sea ice cover during the melting season, with a significant impact on the heat and mass budget of the sea ice and the upper ocean. We have developed a model, designed to be suitable for inclusion into a global circulation model (GCM), which simulates the formation and evolution of the melt pond cover. In order to be compatible with existing GCM sea ice models, our melt pond model builds upon the existing theory of the evolution of the sea ice thickness distribution. Since this theory does not describe the topography of the ice cover, which is crucial to determining the location, extent, and depth of individual ponds, we have needed to introduce some assumptions. We describe our model, present calculations and a sensitivity analysis, and discuss our results

Modeling the summertime evolution of sea-ice melt ponds

1] We present a mathematical model describing the summer melting of sea ice. We simulate the evolution of melt ponds and determine area coverage and total surface ablation. The model predictions are tested for sensitivity to the melt rate of unponded ice, enhanced melt rate beneath the melt ponds, vertical seepage, and horizontal permeability. The model is initialized with surface topographies derived from laser altimetry corresponding to first-year sea ice and multiyear sea ice. We predict that there are large differences in the depth of melt ponds and the area of coverage between the two types of ice. We also find that the vertical seepage rate and the melt rate of unponded ice are important in determining the total surface ablation and area covered by melt ponds

Ice formation in the Arctic during summer: false-bottoms

The only source of ice formation in the Arctic during summer is a layer of ice called false-bottoms between an under-ice melt pond and the underlying ocean. Of interest is to give a mathematical model in order to determine the simultaneous growth and ablation of false-bottoms, which is governed by both of heat fluxes and salt fluxes. In one dimension, this problem may be considered mathematically as a two-phase Stefan problem with two free boundaries. Our main result is to prove the existence and uniqueness of the solution from the initial condition.Comment: 22 page

The influence of ocean flow on newly forming sea ice

The heat and mass balance of the Arctic Ocean is very sensitive to the growth and decay of sea ice and the interaction between the heat and salt fields in the oceanic boundary layer. The hydraulic roughness of sea ice controls the detailed nature of turbulent fluxes in the boundary layer and hence is an important ingredient in model parameterizations. We describe a novel mechanism for the generation of corrugations of the sea ice–ocean interface, present a mathematical analysis elucidating the mechanism, and present numerical calculations for geophysically relevant conditions. The mechanism relies on brine flows developing in the sea ice due to Bernoulli suction by flow of ocean past the interface. For oceanic shears at the ice interface of 0.2 s−1, we expect the corrugations to form with a wavelength dependent upon the permeability structure of the sea ice which is described herein. The mechanism should be particularly important during sea ice formation in wind-maintained coastal polynyas and in leads. This paper applies our earlier analyses of the fundamental instability to field conditions and extends it to take account of the anisotropic and heterogeneous permeability of sea ice