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Journal of Oceanography

, Volume 49, Issue 5, pp 535–549 | Cite as

Generation mechanism of higher mode nondispersive shelf waves by wind forcing

  • Yutaka Isoda
Article

Abstract

The higher mode predominance in the current velocity fields associated with wind-induced shelf waves in the nondispersive regime is studied with a special attention to the effect of the geographical boundary, e.g. wide strait or wide bank areas. The effect of such large topographic change is represented by wind forcing with a finite dimension near the geographical boundary. The time development processes of the wind-induced shelf waves is examined in the context of an initial-value problem, where a spatially finite wind stress is applied att=0. Various modes of shelf waves excited at the boundary start propagating simultaneously and develop monotonically within the forcing region. After the passage of such wave, the energy of wind is used to maintain the attained equilibrium condition, i.e. the steady shelf circulation. The current evolution of the lower mode is restricted to the earlier stage because of the large propagation speed. In contrast, the higher mode waves can travel slowly within the forcing region so that the kinetic energy is supplied from wind stress for a long time before the equilibrium condition is established. Consequently, the observation at the fixed point near the geographical boundary would show that the higher mode waves gradually dominate as time goes on, i.e. for the long-term forcing.

Keywords

Wind Stress Current Velocity High Mode Propagation Speed Lower Mode 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Journal of the Oceanographic Society of Japan 1993

Authors and Affiliations

  • Yutaka Isoda
    • 1
  1. 1.Department of Civil and Ocean EngineeringEhime UniversityMatsuyamaJapan

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