Figure 1 - Nearshore Ice Complex

Figure 2 - Ice Shove

Ice on the Shore

The type and amount of ice that forms along the shores varies from location to location and from day to day. A frozen beach is the first ice feature to form. Waves drive slush ice to shore to form an icefoot. On beaches exposed to waves, a nearshore ice complex forms (Figure 1), extending lakeward from the icefoot and containing relatively smooth sheets of ice. Ice ridges form where waves break, such as over nearshore sandbars, and may provide a lakeward boundary for this ice mass.

Waves breaking against grounded ice ridges scour the lakebed, and the lakebed is gouged by contact with the keels of ice ridges moved by the wind. Slush ice and anchor ice that releases from the bottom incorporate sediment. Drifting ice transports significant quantities of sediment along and away from the shore.

Coastal property can be significantly damaged by ice shove. Ice shove (Figure 2) is caused when wind and wave energy is transmitted to an existing ice sheet and pushed onshore. Structures not designed to withstand ice could be extensivelys damaged.