Procedures for preparing short-range (48-hour) forecasts and long-range (15- and 30-day) estimates of austral summer sea ice conditions in the western Ross Sea and McMurdo Sound are given. Magnitude and direction of short-period ice drift are related to pack concentration, topography, and thickness, surface currents, and forecasted surface wind velocities. Long-period ice estimates are based on analog techniques relating various environmental factors to pack growth, extent, and disintegration as well as using the progression of ice melt indicated by selected historical data. Examples of short-range ice forecasts and long-range estimates are given. Techniques are included for interpreting sea ice from satellite imagery.

Climatology, based on ice information from June 1953-February 1981, is presented in terms of percentage probabilities: first, of the ice limit in semi-monthly intervals from October 15 to July 15 and secondly, of the 50 percent concentration boundary in the same interval from May 1 to July 15.