DYNAMICS OF MEDDIES INTERACTED WITH A SEAMOUNT IN A 1.5 LAYER MODEL

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DYNAMICS OF MEDDIES INTERACTED WITH A SEAMOUNT IN A 1.5 LAYER MODEL

In the present paper, a simplified model is proposed to describe the interaction of meddies with a seamount. In the absence of topography, the meddy obtained in this model moves very slowly to the west. However, in the presence of Guassian shaped topography (seamount) the movement of the meddy is strongly controlled by its site. As the seamount is located in the southwest side of a meddy, this meddy will be induced to move southward. But if the seamount is located in the west side of the meddy, the seamount forcing will cause a southwest movement of such a meddy. For two meddies in the absence of seamount, the two meddies will be located on the northwest southeast axis due to their interaction, which is the natural evolution of two anticyclonic eddies. However, the presence of a seamount will cause the meddies to merge rapidly. This merging is also influenced by the site of the seamount, The closer the seamount is to the two meddies, the faster the two meddies merge. In addition, the direction of the corotating two meddies in the northwest southeast axis is also influnced by the site of the seamount.