Publication Date:
2022-05-25
Description:
Author Posting. © American Meteorological Society, 2009. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 39 (2009): 1551-1573, doi:10.1175/2008JPO4152.1.
Description:
A conceptually simple model is presented for predicting the amplitude and periodicity of eddies generated by a steady poleward outflow in a 1½-layer β-plane formulation. The prediction model is rooted in linear quasigeostrophic dynamics but is capable of predicting the amplitude of the β plume generated by outflows in the nonlinear range. Oscillations in the plume amplitude are seen to represent a near-zero group velocity response to an adjustment process that can be traced back to linear dynamics. When the plume-amplitude oscillations become large enough so that the coherent β plume is replaced by a robust eddy field, the eddy amplitude is still constrained by the plume-amplitude prediction model. The eddy periodicity remains close to that of the predictable, near-zero group-velocity linear oscillations.
Striking similarities between the patterns of variability in the model and observations south of Indonesia’s Lombok Strait suggest that the processes investigated in this study may play an important role in the generation of the observed eddy field of the Indo-Australian Basin.
Description:
This work was completed at the Woods Hole Oceanographic
Institution while TS Durland was supported by
the Ocean and Climate Change Institute. MA Spall was
supported by NSF Grant OCE-0423975 and J Pedlosky
by NSF Grant OCE-0451086. TS Durland acknowledges
additional report preparation support from NASA Grant
NNG05GN98G.
Keywords:
Eddies
;
Intraseasonal variability
;
Nonlinear models
;
Shallow-water equations
;
Plumes
Repository Name:
Woods Hole Open Access Server
Type:
Article
Format:
application/pdf
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