"Sea ice is a mixture of freshwater ice crystals," brine", and bubbles containing salt, including freshwater ice (glaciers and river ice) from the mainland and saltwater ice that is directly frozen from seawater. Generally it refers to the latter. In a broad sense, sea ice also includes river ice and icebergs in the ocean. Salt water ice is a mixture of solid ice and brine (including some salt crystals). Its salinity is 2-10 ‰ lower than that of seawater. Physical properties (such as density, specific heat, heat of solution, latent heat of evaporation, thermal conductivity, and expansion) are different from freshwater ice. "