Snow to ice conversion occurs if the snow layer overlying the sea ice becomes thick enough to depress the snow-ice interface below freeboard (the ocean surface). This process is only accounted for when CAM 3.0 is coupled to a mixed layer ocean, otherwise the snow depth is merely capped at 0.5 m. The interface height is:
If , then an amount of snow equal to is removed from the snow layer and added to the ice. It is assumed that ocean water floods the depressed snow, and then converts it into ice of thickness . The energy of melting of the newly formed ice is: . Note that such conversion is assumed to occur with no heat or salt exchange with the ocean.