The Norwegian Atlantic Current is significantly steered by large topographic features of the Norwegian Sea. The geometry of topographic features in the region is highly variable, but the influence of this variation on the formation of a quasi-permanent anticyclonic vortex located in the center of the Lofoten Basin (Lofoten Vortex) is poorly understood. Four sensitivity experiments with a regional configuration of the Massachusetts Institute of Technology general circulation model have been carried out with an objective to investigate the role of bottom topography on the formation of the Lofoten Vortex in the Norwegian Sea. We find that the bottom topography and especially the geometry of subsurface ridges are critical for the dynamics of the Norwegian Sea and stability of the Lofoten Vortex.
Norwegian Sea, Lofoten Basin, Norwegian Basin, bottom topography, MITgcm, topography experiments
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