floes

Floe refers to a flat, relatively thin sheet of ice that floats on the surface of water. In most contexts, floes are fragments of sea ice that have broken away from larger formations such as ice shelves, glaciers, or the seasonal sea ice cover. Floes can also form from river ice in winter.

Floe formation and movement are driven by wind, ocean currents, and temperature. Once formed, floes drift with the ambient flow, and their edges are often irregular. Waves and winds can further fragment floes, while colder temperatures can cause partial freezing of melt ponds on their surface. When floes collide, they may deform into thicker ridges known as pressure ridges.

Size and appearance vary widely. Individual floes can be as small as a meter across or as large as many kilometers in diameter, depending on the source material and environmental conditions. The surface is typically white and reflective, and a layer of snow can cover top surfaces, while the undersides are dark and wet from contact with seawater.

Floes play a significant role in polar marine ecosystems by shaping light penetration, habitats, and nutrient transport. They affect shipping routes and offshore operations, creating hazards and influencing icebreaker requirements. In climate research, the distribution, thickness, and drift of floes are important indicators of sea ice dynamics and regional climate change.

Related topics include pack ice, ice floes, polynyas, and river ice.