A stress–strain relation for dry snow in Greenland and Antarctica was derived. When this relation is integrated, it gives snow density as a function of time. For given surface density, temperature, and accumulation, the age of snow layers can be obtained as a function of depth in the snow-pack. Calculations compare well with observations. With some knowledge of the temperature range in the upper layer of the snow-pack, calculation for density versus depth can also be improved over the results where such temperature information was not used.

A new technique has been developed to estimate digitally the concentration and structure of open-water leads (polynyas) in synthetic aperture radar (SAR) sea-ice data. This procedure consists of smoothing the original SAR sea-ice data to reduce speckle effects, level slicing this smoothed image to produce a binary image consisting of ice and open water, generating the autocorrelation function of this image, and interpreting the autocorrelation function for lead information. Preliminary results indicate that this technique yields useful estimates of lead characteristics, but that additional research is required to evaluate fully its performance.