The 3‐D Structure of Mesoscale Eddies in the Lofoten Basin of the Norwegian Sea: A Composite Analysis From Altimetry and In Situ Data

Abstract

AbstractIn this research temperature and salinity profiles in eddy‐centered coordinates obtained from satellite altimetry (eddy data set distributed by Archiving, Validation and Interpretation of Satellite Oceanographic data) are combined to document the mean three‐dimensional structures of cyclonic (CEs) and anticyclonic (AEs) eddies in the Lofoten Basin. For eddies of both polarities, significant eddy‐induced anomalies are concentrated within the zero vorticity radius and vertically to the depth of ∼900–1,000 m. The thermohaline vertical structures of CEs and AEs differ in terms of salinity and temperature anomalies. Horizontal structure of the mesoscale eddies showed warmer and saltier anomalies for AEs from the southwest to the northeast side, as well as colder and less salty anomalies from their southeast side for the CEs. This reflects the main features of the basin‐scale temperature and salinity gradients, strongly affected by the Norwegian Atlantic Slope Current. Mean zonal eddy‐induced transport of volume, heat, and salt is generally westward, consistent with the key role played by eddies generated by the Norwegian Atlantic Slope Current. The obtained results highlight the significant role played by mesoscale eddies in the oceanic circulation of the Lofoten Basin, as well as on heat and salt budgets of a key region for air‐sea exchanges, water mass transformation, and climate.