Sea ice and iceberg dynamic interaction

[1] A model of iceberg motion has been implemented in the Los Alamos sea ice model (CICE). Individual bergs are tracked under the influence of winds, currents, sea surface tilt, Coriolis, and sea ice forcing. In turn, sea ice is affected by the presence of icebergs, primarily as obstacles that cause the sea ice to ridge on the upstream side or create open water on the downstream side of the bergs. Open water formed near icebergs due to sea ice ridging and blocking of sea ice advection increases level and ridged ice downstream of the bergs through increased frazil ice formation. Resulting anomalies in sea ice area and thickness (compared with a simulation without icebergs) are transported with the sea ice flow, expanding over time. Although local changes in the sea ice distribution may be important for smaller-scale studies, these anomalies are small compared with the total volume of sea ice and their effect on climate-scale variables appears to be insignificant.