An Implementation of Icebergs in CICE

There is an estimated global iceberg calving flux of {approx} 2300 Gt yr{sup -1}, about 90% of which occurs in the Antarctic. Icebergs provide an important vehicle for freshwater injection into the polar oceans, an estimated 60-80% of net freshwater flux from land ice to oceans in the Antarctic. Icebergs interact dynamically with surrounding sea ice, potentially affecting marine eco systems. Icebergs lose mass primarily through three mechanisms, described by empirical relations: (1) Basal melting - turbulence due to differences in oceanic and iceberg motion (also function of difference in temperature between ocean and iceberg); (2) Lateral melting - buoyant convection along sidewalls of iceberg (function of ocean temperature); and (3) Erosion due to waves (function of sea state and ocean temperature). We have incorporated an iceberg parameterization into the CICE model where sea ice responds to the icebergs, rather than being a static forcing term. Icebergs produce highly localized anomalies in sea ice concentration, thickness, and strength. Summer sea ice meltback limits these effects. Icebergs shed freshwater as they move, transporting freshwater away from the coast.