Reflection of equatorial Kelvin waves at eastern ocean boundaries Part I: hypothetical boundaries

[摘要] A baroclinic shallow-water model is developedto investigate the effect of the orientation of the eastern ocean boundary onthe behavior of equatorial Kelvin waves. The model is formulated in a sphericalpolar coordinate system and includes dissipation and non-linear terms, effectswhich have not been previously included in analytical approaches to the problem.Both equatorial and middle latitude response are considered given the largelatitudinal extent used in the model. Baroclinic equatorial Kelvin waves ofintraseasonal, seasonal and annual periods are introduced into the domain aspulses of finite width. Their subsequent reflection, transmission anddissipation are investigated. It is found that dissipation is very important forthe transmission of wave energy along the boundary and for reflections from theboundary. The dissipation was found to be dependent not only on the presence ofthe coastal Kelvin waves in the domain, but also on the period of these coastalwaves. In particular the dissipation increases with wave period. It is alsoshown that the equatorial β-plane approximation can allow ananomalous generation of Rossby waves at higher latitudes. Nonlinearitiesgenerally have a small effect on the solutions, within the confines of thismodel.

Key words. Oceanography: general (equatorialoceanography; numerical modeling) · Oceanography: physical (eastern boundarycurrents)

[学科分类] 地球科学(综合)