A simulation scheme is developed that estimates salinity profiles for first-year sea ice during the growth season as a function of the growth history of the ice. The model considers the dependence of the initial ice salinity on ice growth velocity and seawater salinity and also the subsequent drainage of brine from the ice. The equation for ice growth assumes a linear temperature profile within the ice and is driven by surface heat balance equations that are based on smoothed climatic data for the central Arctic Basin. The estimated salinity profiles are in good agreement with natural profiles. Although temperature and salinity profiles depend upon the time of the year when ice growth is initiated, the brine volume profiles which they specify are essentially a unique function of ice thickness; a conclusion that holds even when the insulative effects of snow are considered. The temperature and brine volume profiles are then utilized to calculate the ice strength and elastic modulus profiles, which in turn specify the composite mechanical properties of the ice sheets through the application of a theory developed by Assur (1967). Significant differences, which are largest for thin ice sheets, are observed between ice sheet properties as calculated using composite plate theory and properties calculated from uniform plate theory and average ice properties. These results provide a justification for the practice, common within the ice modeling community, of parameterizing the mechanical behavior of pack ice on the basis of the ice thickness distribution. ¿ American Geophysical Union 1988