Diagnostics of the destruction of jet zonal flow as an element of oceanic circulation with different localization of wind action

by

A.B. Fedotov

 Institute of Natural and Technical Systems, RF, Sevastopol, Lenin St., 28

E–mail: fedotov57@mail.ru

DOI: 10.33075/2220-5861-2022-4-25-30

UDC 551.465.553                                                 

Abstract:

   Within the framework of a numerical model of a two-layer ocean with a depth of layers corresponding to average oceanic conditions, a study of the evolution of large-scale circulation under the action of a stationary inhomogeneous external flow of vorticity in the meridional direction, simulating the effect of wind on the ocean, with different localization of wind load, was carried out. The experiments were performed for the same initial vorticity field formed using a numerical model using an explicit time integration scheme with constant dissipation parameters, three main wind load localization were selected: at the western shore, in the central part of the settlement area and at the eastern shore. The purpose of these numerical experiments was to study the processes of destruction of the structure of large-scale ocean circulation in the presence of external disturbances, while the wind load field itself was used as such disturbances in the form of a flow of relative vorticity. In all three experiments, the spatial structure of the external vorticity flow was identical except for the longitude of the location of the disturbance zone itself. Experiments have shown that the most sensitive area of the current system to external influences is the area near the western shore, where the jet stream begins to form. With external influence on this area, the destruction processes of an extended jet stream are intensive, and approximately in 6000 days lead to the total destruction of intense jet, on the contrary, with external influence on the eastern and central regions of the осеаn area under consideration, an intense jet does not destroy. The paper analyzes the time courses of kinetic energy of the upper ocean for all three numerical experiments.

Keywords: synoptic variability, large-scale variability, wind-forced currents.

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REFERENCES

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