Reflection Of Rossby Waves Research Articles

Critical level absorption of barotropic Rossby waves in a north-south flow

This paper analyzes propagating wave solutions of the linearized barotropic vorticity equation near a critical level in a north–south flow V(x). The long Rossby wave found to the west of a wave source passes through the critical level unaffected. The short Rossby wave found to the east of a source is attenuated across the critical level by a factor exp (−πβ/lV′), where l is the north–south wave number and V′ the shear at the critical level. Wave velocity components (u, υ) do not become infinite near the critical level. Numerical solutions show how Rossby wave propagation on a large-scale domain is affected by critical level absorption. Implications for ocean basin models where phenomena depend on Rossby wave reflection at a western boundary are discussed.

Effects of western coastal orientation on Rossby-wave reflection and the resulting large-scale oceanic circulation

The effect of the orientation of the western shore on the structure and behavior of large-scale currents in a homogeneous wind-driven ocean of uniform depth is investigated through time-dependent numerical integrations of a primitive dynamical model. These solutions are shown to consist primarily of transient Rossby waves reflected from the western shore, whose characteristics correspond well with the results of linear, inviscid theory during the early part of their life cycle. The reflection of the group velocity of the waves appears to determine the location of maximum current variability in the western part of the basin. The thickening of the boundary current with inclination of the western shore given by linear theory is not detectable with the limited resolution of the present solutions. The maximum speed (and hence probably the total transport) changes in approximate proportion to the basin's average zonal width. The influence of smaller-scale coastal features detectable by the numerical model is confined to the quasi-steady western boundary current.