The Lofoten Basin in the Norwegian Sea is the area where the warm Atlantic Water exhibits the greatest loss of heat than anywhere else in the Nordic Seas. It is called a "hot spot" of the Nordic Seas because of its high intense mesoscale eddy activity. Mesoscale eddies contribute significantly to the total oceanic heat and salt transport by advective trapping, stirring and mixing, and thus play an important role in the heat and salt balance of the region. A purpose of this study is to examine seasonal variability of mesoscale eddies in the Lofoten Basin using satellite altimetry data and GLORYS reanalysis. Satellite altimetry is used to track individual eddies, and co-located vertical profiles based on GLORYS data allow to study thermohaline characteristics inside the eddy cores. We analyze numbers of cyclonic and anticyclonic eddies in the Lofoten Basin using an eddy identification and tracking algorithm and demonstrate that the occurrences of eddies depend strongly on the season. We analyze seasonal variability of temperature, salinity, and potential density anomalies in zonal sections across the core of the Lofoten Vortex and explore spatial variability of thermohaline characteristics of mesoscale eddies at the depth of 450 m in different seasons.
Lofoten Basin, Norwegian Sea, mesoscale eddies, altimetry, automatic detection
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