Effects of Wind, Waves, and Currents on Icebergs and Surface Floats in the Labrador Sea: A Modeling Study

This article presents a model study of the dynamics of icebergs and surface floats in the Labrador Sea. The model was forced with data on the wind above the ocean surface, surface waves, and ocean currents. These data were obtained from the reanalysis of near-surface characteristics of the ocean and atmosphere for the year 2008. Icebergs and floats launched in an area north of the Labrador coast and to the east of Greenland generally move southeastward until they reach a boundary current “highway”. After that, they are carried by ocean currents into the central part of the subpolar North Atlantic. Simulations demonstrated that, for smaller icebergs, the primary balance is between the air and water drag, while for larger icebergs, it is between three forces: the air and water drag and the combined Coriolis and pressure forces. Floats, on the other hand, are driven mostly by the Ekman component of the surface velocity, while the geostrophic and Stokes components are less important. The significant variability in the motion of icebergs and floats is due to storms passing over the Labrador Sea, since these high-wind events introduce time-dependent dynamics.