Evolution of an Intrathermocline Lens
over the Lofoten Basin
Boris N. Filyushkin, Mikhail A. Sokolovskiy
and Konstantin V. Lebedev
Introduction
Systematic oceanographic surveys conducted by the Arctic and Antarctic Research
Institute during the period 1970–1990 in the region of the Lofoten Basin (LB) of the
Norwegian Sea proved the existence of a quasistationary anticyclonic vortex
(AV) [2]. Six consecutive oceanographic surveys occupied in 1987–1988 have
shown the existence of a synoptic-scale (diameter was about 60 km) vortex (a lens)
and instrumentally confirmed its anti-cyclonic character. At the same time, during a
year, the AV have been drifting almost along a closed cyclonic orbit (with a
horizontal latitude scale about 130 km) while its core was still located in the
deepest part of the LB (the isobath 3200 m) [6, 7] and Fig. 1 of this contribution.
The development of the Argo project in the first years of the 21st century in
addition to the neutral buoyancy floats observations started in the beginning of the
1990s, provides opportunities for studying the structure and circulation of water in
the LB. New observations confirmed the existence of a quasi-permanent AV and
the fact that the cyclonic circulation dominates in the depth range 600–1000 m
within the deepest part of the LB [5, 12, 14, 22]. Detailed measurements performed
by the RAFOS floats and Doppler current velocity meters revealed a complex
pattern of the formation and existence of a large number of mesoscale vortices that
differ in their lifetime and scale. At the same time, the number of vortices in the LB
fluctuated throughout the year [19]. Similar results were also obtained from satellite
observations of variations in the sea surface height (SSH) and the sea surface
temperature [8, 15, 23]. In these publications, satellite images based on weekly
B. N. Filyushkin ( ✉ ) ⋅ M. A. Sokolovskiy ⋅ K. V. Lebedev
Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russia
e-mail: borisfil@yandex.ru
M. A. Sokolovskiy
Water Problems Institute, Russian Academy of Sciences, Moscow, Russia
© Springer International Publishing AG, part of Springer Nature 2018
M. G. Velarde et al. (eds.), The Ocean in Motion, Springer Oceanography,
https://doi.org/10.1007/978-3-319-71934-4_21
333
over the Lofoten Basin
Boris N. Filyushkin, Mikhail A. Sokolovskiy
and Konstantin V. Lebedev
Introduction
Systematic oceanographic surveys conducted by the Arctic and Antarctic Research
Institute during the period 1970–1990 in the region of the Lofoten Basin (LB) of the
Norwegian Sea proved the existence of a quasistationary anticyclonic vortex
(AV) [2]. Six consecutive oceanographic surveys occupied in 1987–1988 have
shown the existence of a synoptic-scale (diameter was about 60 km) vortex (a lens)
and instrumentally confirmed its anti-cyclonic character. At the same time, during a
year, the AV have been drifting almost along a closed cyclonic orbit (with a
horizontal latitude scale about 130 km) while its core was still located in the
deepest part of the LB (the isobath 3200 m) [6, 7] and Fig. 1 of this contribution.
The development of the Argo project in the first years of the 21st century in
addition to the neutral buoyancy floats observations started in the beginning of the
1990s, provides opportunities for studying the structure and circulation of water in
the LB. New observations confirmed the existence of a quasi-permanent AV and
the fact that the cyclonic circulation dominates in the depth range 600–1000 m
within the deepest part of the LB [5, 12, 14, 22]. Detailed measurements performed
by the RAFOS floats and Doppler current velocity meters revealed a complex
pattern of the formation and existence of a large number of mesoscale vortices that
differ in their lifetime and scale. At the same time, the number of vortices in the LB
fluctuated throughout the year [19]. Similar results were also obtained from satellite
observations of variations in the sea surface height (SSH) and the sea surface
temperature [8, 15, 23]. In these publications, satellite images based on weekly
B. N. Filyushkin ( ✉ ) ⋅ M. A. Sokolovskiy ⋅ K. V. Lebedev
Shirshov Institute of Oceanology, Russian Academy of Sciences, Moscow, Russia
e-mail: borisfil@yandex.ru
M. A. Sokolovskiy
Water Problems Institute, Russian Academy of Sciences, Moscow, Russia
© Springer International Publishing AG, part of Springer Nature 2018
M. G. Velarde et al. (eds.), The Ocean in Motion, Springer Oceanography,
https://doi.org/10.1007/978-3-319-71934-4_21
333